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The fundamentals of naval tactics
olin
3 1924 030 751 923
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THE FUNDAMENTALS
OF
NAVAL TACTICS
THE FUNDAMENTALS
OF
NAVAL TACTICS
BY
ROMEO BERNOTTI
LIEUTENANT, ITALIAN NAVY
Translated by H. P. McINTOSH, Lieutenant, U. S. Navy
Annapolis, Md.
The United States Naval Institute
1912
(■ f' (; K' I ! I
BALTIMORE, MD., U. S. A.
FOREWORD.
This work is a systematic codification in treatise form of the
mathematical principles of Naval Tactics. The author is the
instructor in the Art of Naval War at the Royal Italian Naval
Academy, and his name is well known as the writer of a number
of excellent articles of much original thought on naval tactics in
the Revista Marittima.
He is therefore well fitted for the task of reducing to the con-
secutive order and logical sequence, so necessary to the student,
tactical principles and theorems. Tactics is an ever changing art ;
for while its scientific principles do not change, its rules neces-
sarily change with changing conditions.
No books on tactics will ever solve the problem finally, because
the problem is forever changing ; but if its methods are correct,
these will ever be of value.
Even if we do not agree with all the views of the author and of
the other of his distinguished compatriots whose views he has
here embodied, the work would be of value as expressing the
Italian point of view ; and Italy stands in the first rank of naval
thought.
As the title indicates, the book deals chiefly with the funda-
mentals, and approaches the subject more particularly from the
mathematical side.
W. McCarty Little,
Captain, U. S. Navy.
U. S. Naval War College,
Newport, R. I.,
April 3, igii.
TABLE OF CONTENTS.
Introduction ix
PART I.
The Elements of Maneuvering.
I. Direction of Maximum Utilization i
11. Radius of Action of the Torpedo 13
III. Advantageous Positions 25
IV. The Fighting Distance 44
PART II.
Maneuvering.
I. Ideas on Naval Kinematics 57
II. Maneuvers of Two Ships Opposed to Each Other 84
III. Tactical Evolutions 105
IV. Tactical Maneuvers 133
V. Torpedo-Boat Maneuvers 161
PART III.
I. Preparation for Tactical Contact 171
II. The Battle 179
INTRODUCTION.
The study of naval tactics has for its object the employment
of ships in battle. This does not mean that the field of such in-
quiry is limited simply to that in which the weapons are in action
(oifensive contact) ; indeed it is well understood that, directly in
relation to the battle, the movements of the two adversaries from
the time of their sighting each other are to be considered ; further-
more, on the information obtained from the units that keep the
enemy in sight, the remainder of the forces can be arranged in
the most opportune way for its tactical employment. Therefore,
under the head of tactical contact, besides the above-mentioned
form (offensive contact), it is well to include also that of contact
out of range.
To proceed from the simple to the complex, let us examine
successively :
I. The elements of maneuvering; seeking to establish the im-
portance of the various elements (angles and distances) by means
of the examination of the inom,entary tactical situations; con-
sidering the mobility of the adversaries only in so far as it affects
the probability of hitting with the weapons.
II. Maneuvering; examining how, by its effect, the tactical
situation may be subjected to change.
III. Tactical action as a whole, on the basis of the above-men-
tioned parts, completing the picture of the battle which results
from them.
One may find a certain reluctance in admitting the convenience
of studying the momentary situation apart from the maneuvering,
but it is necessary to consider that if the study of the movement
is put first, it would appear to be necessary to leave the other out.
Romeo Bernotti,
Lieutenant, Italian Navy.
The Fundamentals of Naval Tactics.
PART I.
THE ELEMENTS OF MANEUVERING.
CHAPTER I.
Directions of Maximum Utilization.
1. Definitions. — We call long-range combat that which is de-
veloped within the limits of distance which permit the use of
guns only.
By the polar bearing of a point is meant the angle that the line
joining the center of the ship with that point makes with one of
the principal directions of the ship (direction of the bow, or of
the stern, or of the beam) .
The polar bearing of a ship that is being fired upon is also
called the inclination to the plane of fire.
2. Sectors of Maximum Offense. — Let us examine the manner
in which the offensive power of a ship varies with the variation
of the inclination to the plane of fire.
First of all, let us suppose that the ship under consideration is
armed with guns of a single caliber.
By taking into account the fields of fire, the number of the guns
that fire in the different directions is determined. The variations
of the offensive power may usefully be represented by means of
a polar diagram, whereon the principal directions of the ship are
traced, and whereon, for eveiy inclination, the radius vector has
a length proportional to the number of guns that can fire in that
direction.
The offensive field may not be uniform.
The first monitor had two dismountable smoke-stacks ; and so
the armament, enclosed in a single revolving turret, had a field of
fire of 360°.
A type of ship that could satisfy such requirements would
secure to the single guns the maximum utilization ; but if we
establish it as an axiom to consider every ship as an organic unit
of the fleet, and then seek to obtain the maximum return from
the whole organization, we must admit the necessity of having the
The Fundamentals of Naval Tactics.
same kind of guns on every ship. Tliis being the case, in order
that the offensive field might be uniform, it would be necessary,
ideally, to have a number of guns on a circumference, each gun
with a field of fire of r8o°. The number of the guns being prac-
tically limited, there follows the possibility of having some of the
guns with a greater field of fire than the one just mentioned,
which involves the necessity of the offensive field having its maxi-
mums and its minimums.
When long-range combat was held to be only a transitory phase
of the action, it was drawn therefrom as a corollary that the
maneuvering should be independent of the employment of the
guns ; therefore it was sought to approximate to a circular ar-
rangement, securing the development of the maximum offensive
power in the principal directions of the ship. Thus there was
designed for the heavy guns an arrangement on a diagonal
(Duilio), and in a lozenge, adopted by the French. Thus, also,
disposing a battery of medium guns about the sides of a lozenge,
given the fact that each gun may fire very close to another
situated further inboard, we may say that the above-mentioned
object is attained. With arrangements of this nature, if, starting
from the beam of the ship, we consider the offensive power de-
veloped in the various directions, we find that the maximum
power is developed up to a certain angle from the beam ; beyond
this limit, the power falls to a minimum, it becoming possible to
fire only with the guns in one quadrant, until, in the direction of
the keel — since there the guns of the other side enter also into
action — we have again the maximum offensive potentiality. Thus
we have, laterally, sectors of maximum offense and sectors of
minimum offense ; in the direction of the keel we have a direction
of maximum offense, but not a sector.
At present the power of the artillery compels us to consider the
long-range combat as a most important form of action, in which
it is necessary to subordinate the maneuvering to the good em-
ployment of the guns, without, however, creating too difficult
conditions for the maneuvering. From this principle we imme-
diately derive the consequence that simple directions of maximum
offense badly satisfy the tactical necessities. It is then necessary
to direct the mind not so much to the importance of uniformity
in the offensive field, as to securing for this field the maximum
intensity where most convenient. On this basis it must be re-
The Fundamentals of Naval Tactics.
membered that, in every discussion of the distribution of the
offensive power, the amplitude of the fields of fire of the single
guns must serve as basic data only; the important thing is the
manner in which the various fields of fire blend together.
Since ships are longer than they are broad, the maximum num-
ber of guns can be placed along their length ; in such case the result
of the distribution of the offensive power still remains, as already
mentioned ; or, from sectors of maximum offense we pass to those
of minimum offense, with a new increase of power when we
reach the line of the keel ; however, the power in the latter direc-
tion is inferior to the maximum. The nearer we approach the
arrangement of all the guns on the longitudinal axis, the more
we increase the said inferiority, and at the same time we increase
the amplitude of the sectors of maximum offense; and, recipro-
cally, the greater the similarity between the power in line with the
keel and that of the sectors of maximum offense, the smaller is
the amplitude of the said sectors.
When the armament is composed of guns of different calibers,
in order to establish the elements of the distribution of the offen-
sive power that are important in long-range combat, it is evidently
necessary to proceed in the following manner: (i) Exclude the
guns that are inefficacious in the said form of action ; thus, for in-
stance, in battle between armored ships, only the guns above a
caliber of about 15 centimeters are to be considered. (2) Deter-
mine the sectors of maximum and minimum offense for the cali-
bers that are useful in long-range battle in the manner above
mentioned. (3) Observe how the sectors of the various calibers
intermingle.
Rigorously, we should hold to be sectors of maximum offense
of the ship all those common to the sectors of maximum offense
of the various calibers. Their amplitude would hence be deter-
mined by the caliber having the most limited sectors ; however,
it is easy to understand how the amplitude in question may be
considered as increased when we take into account the relative
importance of the different parts of the armament. In long-
range battle the maximum caliber has predominating importance ;
hence it is its distribution that should essentially be considered.
Ordinarily, in the interval between the extremes of the sectors
of maximum offense of the maximum caliber, and those of the
sectors in which we have, absolutely speaking, the maximum of
The Fundamentals of Naval Tactics.
power, the variation may be held to be negligible. More in
general, by considering the importance that each kind of gun has
in the composition of the armament, it will be easy to establish
what caliber shall determine the amplitude of the sectors of
maximum offense which it will be well to take as the standard
in tactical employment.
The search for the best disposition of the guns forms no part
of the study of tactics, although it is of consequence to it; for
this reason we confine ourselves to simple statements concerning
the manner in which the offensive field is distributed in the exist-
ing types of ships.
Generally the offensive field is symmetrical with respect to the
longitudinal axis * and to the transverse axis.
Dissymmetry with respect to the beam would be advisable
whenever we might, with reason, establish a greater probability
of fighting with the enemy bearing forward of the beam than
abaft the beam, or vice versa; for the present we confine our-
selves to noting that we may not exclude the convenience of
keeping the enemy abaft the beam, when this is not done in order
to avoid action.
In general, between two scouting vessels, one will be interested
in bringing about an action, and the other in avoiding it; the
tactical maneuvers will thus assume the form of a pursuit. It is
not simply a question, as above indicated, of keeping the enemy
forward of or abaft the beam, with the object of causing the
tactical action to" assume the form that we desire, but, more prop-
erly, it is a question of chasing or being chased ; hence the power
of the fire in the direction of the keel will have greater importance
than in the types of ships not destined for detached service ;
this explains why, in the light ships, we seek to obtain directions
of maximum offense in line with the keel.
* A dissymmetry with respect to the longitudinal axis would obtain, for
example, with two turrets arranged, one on the starboard side and the
other on the port side, very near to each other, with their centers in a
direction inclined to the said axis, when the guns of one turret are higher
than those of the other, so as to permit firing over them; dispositions of
this nature would oblige us to present to the enemy a definite side. The
study of tactical maneuvering will show us how harmful this limitation
may be. (Author's note.)
The Fundamentals of Naval Tactics.
The types of armored vessels that at present compose the fleet
can, on the basis of their armaments, be grouped in the follow-
ing categories :
(i) Antiquated ships, in which the sectors of maximum ofifense
extend about 30° forward of, and about the same distance abaft,
the beam.
(2) Modern ships (not specially constructed for long-range
battle). In these ships the distribution of the fire is about as
follows: (a) Maximum intensity in a restricted sector in the
vicinity of the beam, (b) Intensity a little inferior to the maxi-
mum, and practically to be considered as maximum, in the sectors
of 4S°-5o° forward of and abaft the beam, (c) Minimum inten-
sity in the sectors between the direction of the keel and 45° from
the beam, (d) Strong intensity in line with the keel.
(3) The most modern ships, that, by the disposition of their
armaments, may be divided into two categories : (a) Those with
turrets on the longitudinal axis and on the sides, or with a part
of them on the axis and a part of them removed therefrom ; the
sectors of maximum offense, with an amplitude of about 45° for-
ward of, and 45° abaft, the beam, as in the modern ships, (b)
With all the turrets on the longitudinal axis ; the sectors of maxi-
mum ofifense extend to 55" or 60° forward and abaft, and, as a
maximum limit, to 70°.
In the discussion of tactical employment it is therefore neces-
sary to take as a basis the following data: The amplitude of the
sectors of maximum offense, in the generality of present-day
vessels, is from 45° to 50° forward of and abaft the beam. In
some ships this amplitude is 30", and in others it is 60° forward
of and abaft the beam.
3. Inclination amd the Probability of Being Hit. — ^Within the
limits thus determined for the sectors of maximum offense, we
propose to estimate the influence that the inclination of the ship
to the plane of fire (which we will count from the beam) has
upon the percentage of effective hits made by the enemy.
We may hold, approximately, that the target presented by our
ship has a certain uniform height q above the sea, and that its
horizontal section is an ellipse, with its axes respectively equal to
the length L, and to the maximum breadth / of the ship itself.
Let PTP'V (Fig. i) be the section corresponding to the water-
line ; PP' and TV being respectively the longitudinal axis and
The Fundamentals of Naval Tactics.
the transverse axis. If TON^xj/ is the inclination to the plane of
fire, by projecting on the sea the contour of the upper section of
the target, in the direction of the trajectories of all the shots that
would touch that upper section, we delineate on the surface of
the sea another ellipse which may be held to be identical with the
first. The corresponding points of the two ellipses are distant
Fig. I.
from each other -2--, a. being the angle of fall of the projectiles.
If MM^ and M'M\ are the traces of the planes tangent to the
target, drawn parallel to NO, the thin, fictitious, horizontal tar-
get, to which we may refer for the question we are discussing, is
limited by the portion MNM' of the water-line, by the two seg-
ments MM^ and M'M\, and by the remaining portion of the
ellipse M^N\M\.
6
The Fundamentals of Naval Tactics.
Indicating by Aij/ the depth NN\ of the fictitious target in the
direction of the plane of fire, by the known properties of the
elHpse * we have
A^=NN'+ —2- = ^ + -?- ,
tan 0) X tan u
making
\=\/P sin'' „, A„ and B„ are respectively the values of p^, A^/ and B^f,
iox xp=^o (that is, with the ship placed normally to the plane of
fire), making
we obtain
For a battle we may not attribute to the 50 per cent stretches
the values that are taken from the range tables, but we may
establish rational limits that include the values of p. This being
the case we note that by entering the table of factors of prob-
abilities- with a value P [4^) , we may obtain therefrom -^,
which, multiplied by -^ , gives us ^^ , with this argument, we
obtain from the table above mentioned, p (-^] . which, divided
by /) 1':^) , gives us a value of K'^. We obtain K"\^ by an anal-
ogous operation.
The values of ^ and ^ are functions of by the corresponding values of K'\l>, we
have the values of i^^.
'f'
jP'^i
K^,
0°
I
I
30°
1
I
45°
0.9
I
60°
0.8
I
70-
0.6
0.9
At the greatest distances an important lateral dispersion is
inevitable. Under the not exaggerated hypothesis that out of
100 shots we may have 80 good in direction, we obtain
■f"
JT".;-
K'i,
0°
I
I
30°
0.9
0.9
45°
0,8
0.9
60°
0.6
0.7
70°
0.4
0.6
The Fundamentals of Naval Tactics.
Hence we draw the following deductions :
(i) Within the limits of distance in which there is certainty
that all the shots will be good in direction, the probability that the
ship will be hit increases almost insensibly with ij/ varying from
o° to 45°, and afterwards it increases rapidly.
(2) Within the limits of distance in which the above-mentioned
certainty is had only when the ship presents her beam, the direc-
tions included in the sectors of maximum offense are unimpor-
tant in so far as the probability of the ship being hit is concerned.
(3) At the greatest distances, the directions that are not re-
moved more than 45° from the beam may still be considered
unimportant with respect to the probability of the ship being hit ;
this probability undergoes a notable diminution at the extreme
limits of the sectors of maximum offense of ships with all the
heavy guns located on the longitudinal axis.
It is moreover to be noted that, in the hypothesis that for
(o=io°, we have /)|-— ^] = io per cent, ^(^^] = 8o per cent,
for i/' = 90°, or when the ship presents herself end on, we have
K'\j/=2.6, K"\p=o.2; and hence, K\p = o.^; which, compared with
the other values of K\jj already calculated, shows that, at the
maximum lighting distances, a ship that presents herself end on,
diminishes in that way the percentage of the enemy's effective
hits.
The preceding deductions avail for the hypotheses that may be
made concerning the dimensions of battleships.
4. Inclination and Protection.: — When it is said that a certain
gun is capable of perforating a given thickness of vertical armor
at a given distance, it is with reference to the hypothesis that the
projectile arrives in a horizontal direction, normally to the plate,
and that the latter is exactly vertical. As is well known, in battle,
in the most favorable case for the gun, that is, when the plane of
fire is normal to the plate, the conditions differ from those above
stated for the following principal reasons: (i) The divergence
of the axis of the projectile (supposed to be coincident with the
direction of movement) from the normal to the plate, owing to
the angle of fall and to the oscillatory movement of the target.
(2) The divergence of the axis of the projectile from the direc-
tion of its movement. (3) the elasticity of the entire hull, which
forms one body with the armor. We deduce from this that, in
battle, a plate normal to the plane of fire is capable of resisting a
The Fundamentals of Naval Tactics.
projectile that, with the same velocity of impact, would perforate
it under the conditions of trial at the proving grounds. With
reference to the battle, the hypothesis that the projectile arrives
horizontally, with its axis coincident with the direction of move-
ment, may then be taken into consideration ; observing, however,
that the results that are deduced therefrom have reference to
limit conditions of efficacy of the projectile, that is to say, to
ideal conditions, not attainable.
This being understood, if, under the proving ground condi-
tions, and with the plane of fire normal to the plate, a projectile
animated by a velocity of impact v is capable of perforating a
thickness of armor s, on the other hand, when the plane of fire is
inclined to the normal by an angle, i^, the perforable thickness is
Si, less than s; and this does not depend solely upon the fact that
there is disposed normally to the plate only a component of the
yelocity, but also upon the greater distance that the projectile
must travel in the plate itself. This being the case, we may hold
that the conditions of oblique impact are equivalent to those of
normal impact with a velocity of impact v cos h\i, where /i is an
opportune coefficient.
Applying the De Marre formula for perforation successively
to the case of normal impact and to that of oblique impact, and
indicating by F the product of the terms of said formula, inde-
pendently of the thickness of the plate and of the velocity of im-
pact, we have
z/=cos htl'^Fst"-'' ;
and hence
Si = s(cos hp)-iT.
In order to establish the value of h, let us note first of all that,
concerning oblique fire, the data are scant and the formulas are
uncertain. It appears to be proved that the cap of the projectile
may have among its advantages that of approaching the axis of
the projectile to the normal to the plate ; and hence, for moderate
values of t/^, it seems that we may hold h = i. With the increase
of i/r (that is to say, when the obliquity of fire is greater), the
efficacy of the cap diminishes, and the perforable thickness Si is
less than that obtained by making /}=i. Consequently it is log-
ical to admit that h may be a function of \f/. For i/'=6o° the
rebounding of the projectile is realized (when the thickness of
The Fundamentals of Naval Tactics.
the plate is not excessively less than the caliber of the projectile),
and hence vcos(h6o°) =o; from which h^i-S-
Admitting that h varies proportionally from the value of h=i,
which corresponds to V^it-t').
The difference between the radii of the two circles considered
is therefore greater than the distance between the centers ; or,
the two circles have no points in common.
The circle traced for the greatest run to which corresponds a
sufficient probability of hitting, therefore includes the danger
zone with respect to the torpedoes.
The eccentric position of the ship in this zone so determines
matters that a combatant may find himself within the radius of
action of the enemy's torpedoes, without having the enemy within
the radius of action of his own torpedoes. Thus, in Fig. 3, the
ship N has the enemy M in his danger zone, while it is itself out-
side of the zone of M (which has a center at Af^, such that
MMi = NNi). This leads to the establishment of the prefereiice
that is possibly to be given to bearings abaft the beam, in the field
of the torpedo.
10. Concentration of Torpedoes. — The circle, traced as above
described for the maximum run of the torpedo (6500 meters),
limits the danger zone for the concentration of torpedoes. This
zone is greatly extended forward of the ship's beam ; indeed, the
launching distance NS, corresponding to the minimum forward
angle of impact, is even slightly greater than 10,000 meters, for
the ordinary speed of 20 knots per hour, which, at present, it is
well to hold as the mean battle speed.
The Fundamentals of Naval Tactics.
By virtue of what has been said in section 8, we observe that,
at the limit of this danger zone, the percentage of effective tor-
pedo hits is very small. We have seen, in fact, that to a mean
error of io° in the course of the target, there corresponds a mean
miss of 473 meters ; and that for an error of one meter per
second in Vu we have a mean miss of 419 meters ; hence, the
probable mean error that must be reckoned upon in virtue of the
two partial errors aforesaid, is 534 meters. The 50 per cent
stretch is thus 1068 meters, and the percentage of effective hits
against a ship 200 meters long, is, then, 10 per cent.
On this basis, there would appear to be rational a concentration,
which, however, should be executed with at least five torpedoes ;
thus having the probability of obtaining the result that may be
expected from a single torpedo, launched for a run of 2500
meters.
This cannot be accepted unconditionally; in fact, the above
mentioned value of the miss, due to the error in the course of the
target, has reference to the hypothesis of a perpendicular impact.
The miss increases with the obliquity of the impact, and besides,
it must be remembered that, with the same length of run for the
torpedo, the error committed in the estimation of the course and
of the speed is evidently greater the greater is the launching
distance.
It seems logical, then, to admit the possibility of having, with
a run of 6500 meters, 10 per cent of effective hits, when, however,
the impact is normal.
The position H, from which a hit with normal impact can be
made with a run of 6500 m.eters, is found to be at a distance of
7500 meters from the ship.
It is clear that, from this distance, the ship N can render im-
possible the concentration of the torpedoes of several ships by
means of an opportune hindrance of their maneuver; so dispos-
ing that the enemy's line may not be a secant of the danger zone
in the segment occupied by the formation.
This hindrance may be determined by deducing graphically the
maximum launching distances for the different bearings from
the ship's head, which permits fixing the idea in the following
manner: In order to have the certainty of rendering impossible
the concentration of torpedoes, the enemy's ships must not be
brought to bear at less than a certain angle from the bow, which
23
The Fundamentals of Naval Tactics.
angle is respectively 60", 90" and 120", for ships distant about
7500, 4500 and 3500 meters.
It is well to observe that, for the concentration of torpedoes,
two conditions are required : ( i ) The line of formation of the
ships launching the torpedoes must be suitably inclined with
respect to the line joining it with the adversary.
(2) The course of the latter must be favorable to the launch-
ing, and it must be kept exactly constant for the duration of the
run of the torpedo; a duration that, for long runs, is very
considerable.
Since, in a combat between battleships, we cannot, as in the
attack of torpedo boats, count upon a surprise for taking up an
advantageous position, it is not very probable that the two con-
ditions above mentioned can be realized at one and the same time.
It seems allowable, then, to conclude that, although the con-
centration of the torpedoes of several ships may not be absolutely
prevented within the radius of 7500 meters (and this renders it
advisable not to bring the enemy to bear in the neighborhood of
the bow), still, there is no great cause for apprehension concern-
ing it ; and, reciprocally, it is not well to rely too much upon this
employment of the weapon.
II. Launching Against an Assemblage of Vessels. — As is well
known, on the basis of the theory of probabilities, a target, the
extent of which in a certain direction is four times the length of
the 50 per cent stretch, includes all the shots.
In the preceding section, it is seen that a 50 per cent stretch,
about 1000 meters long, corresponds to the maximum run of the
torpedo; consequently, all the shots are included in a formation
that extends at least 4000 meters normally to the mean track of
the torpedoes.
The launching must be directed to strike the center of the for-
mation ; and, naturally, from what has just been said, its success
must depend upon the course of the ships attacked, with a prob-
ability that the track of the torpedo may cut the formation in one
of the vacant spaces. It is well to note that, for formations in
single line and at a distance of 500 meters between the centers
of two adjacent ships, in the most favorable case of L = 200
meters, the said vacant spaces amount to about three-fifths of the
total line.
Hence, we may not exclude the case that some ship may be in
a position for launching with a fair probability of hitting, but it
24
The Fundamentals of Naval Tactics.
is not well to rely upon launchings by several vessels against the
enemy's assemblage, unless the formation of the latter is of
extraordinary length, or unless he adopts a bow and quarter-Une
formation, and unless his course is favorable.
In employing torpedoes, either with a view to concentration or
when considering the enemy's fleet as a single target, it is well to
bear in mind that we face the following dilemma: either we
launch from a long distance and very probably only waste tor-
pedoes, or we launch from a distance somewhat greater than the
limit established for the case of two ships opposed to each other,
and so run the risk of being found unready to launch them within
the really effective radius of the weapon, should the distance
rapidly be shortened in an unforeseen manner.
In conclusion, beyond the range of 3500 meters determined in
section 8, the employment of the torpedo may not be excluded,
but is only occasional ; so that, from the point of view of the
defense, there is no occasion to trouble oneself very much about
it ; and from that of the offense, it is well not to sacrifice, even in
a minimum degree, the employment of the gun.
CHAPTER III.
Advantageous Positions.
12. Alignments. — The formation of a fleet of ships is defined
by the lines joining the units of the formation, and by the angles
that these lines make with the direction of movement.
The study of tactics cannot be reduced to that of fixed forma-
tions, the importance of each single formation not being absolute
but relative to the situation of the moment.* The idea, then,
that the formations are to be considered as consequences of the
maneuvers, having the objective of acquiring or maintaining
determined relative conditions of position with respect to the
enemy, must be held to be fundamental. From this arises the
necessity of fixing in the mind the advantageous positions in
long-range combat, and of doing this in a way that, as far as
possible, may be independent of the formations.
* " C'est moins I'ordre qui a de rimportance, que la position relative des
combattants ; . . . . tout I'effort doit tendre a donner a ses forces une posi-
tion de combat favorable." Daveluy, L'esprit de la guerre navale—La
tactique, 1909.
25
The Fundamentals of Naval Tactics.
In order to obtain such maximum generality of reasoning, it is
principally necessary to have reference to the relative position
of the lines of the enemy's formation, supposing the inclination
of the ships on their respective lines to be variable.
Naturally, it is necessary to take into account the length of the
various segments of the line occupied by each party. To the
geometrical figure composed of these segments we virill give the
name oi alignment (schieramento).
A few definitions are necessary concerning the various kinds
of alignment that it is well to distinguish, in relation to the hypoth-
eses that we shall have to consider.
We say that a naval force has a double alignment when its
ships are arranged on two adjacent parallel lines; the alignment
of a naval force is sim,ple when it is in single line.
Alignments may be rectilinear and curvilinear; we will call
angular the alignments composed of two rectilinear segments that
are not prolongations of each other.
When a naval force maneuvers by separate groups, by align-
ment of the naval force, we mean that composed by the segments
that join the centers of the single groups ; the alignment of each
group being defined in the manner above stated.
By the inclination of a rectilinear alignment we mean the angle
formed by the alignment and the line joining its center with the
center of the enemy's alignment.
13. Zones and Sectors of Offense. — In order to fix these ideas,
let us first of all suppose that we have, in column of vessels (Fig.
4), a naval force composed of ships whose sectors of maximum
offense extend 45° forward of and 45" abaft the beam. It is
clear that if we draw from the leading ship the straight lines AH,
AH', making angles of 45 ° from the bow ; and from the rearmost
vessel the straight lines CK, CK', making angles of 45° with the
direction opposite that of the course, these lines, and the length
of the formation, limit the zones HACK, H'ACK', which are
those of maximum offense, when, however, the ships do not all
fire at one and the same target.
Rigorously, from the above-mentioned zones it would be neces-
sary to subtract those of minimum offense, ADB, BEC, .....
but it is evident that these need not be taken into account except
at short distances.
26
The Fundamentals of Naval Tactics.
The said zones HACK, H'ACK', and the corresponding sectors
of minimum offense, HAH', KCK', refer to the case of the dis-
tribution of the Hre; while it is evident that, under the hypothesis
of the concentration of the Hre, the sectors of minimum offense —
for the formation under consideration — are wider, and the zones
of maximum offense are more restricted.
As, for a ship, we distinguish the sectors of maximum, and
those of minimum offense, so, for any formation, there exist
zones of maximum offense,* and sectors of minimum offense.
(b)
Fig. 4.
Fig. S-
If, instead of to a special, formation, we refer to the alignments
in general, the amplitude of the zones of maximum offense are
determined, taking into account the inclination of the ships which
is most opportune for diminishing the amplitudes of the sectors
of minimum offense. With this object, given a simple rectilinear
alignment, A A' (Fig. 5a), the inclination just mentioned is deter-
mined by the limit condition that each ship, firing in an extreme
* We say zones, and not sectors, as in the case of a ship, because, if the
ship may tactically be considered as a point, the length of the formation is
anything but negligible. (Author's note.)
27
The Fundamentals of Naval Tactics.
direction of a sector of maximum offense (the angle which this
direction makes with the longitudinal axis we will call a), tan-
gents the ship adjacent. Indicating by e (Fig. 5b) the angle thus
made between the alignment and the direction of the plane of
fire, with d as the interval between ships and with L as the length
of each ship, from the triangle OAP ( being the point in which
the alingment intersects the line PP' joining the extremities of
two adjacent ships) we have
sin* sin a
AP OA '
and hence
L .
smf= — r-sina,
a
from which, with the mean data (£=150 meters, ^ = 500 meters,
a = 45°), we obtain e=i2" ; for safety's sake let us say £=15°.
From this it follows that, if we draw from the extremities of
the alignment four right lines forming angles of 15" with the
prolongation of said alignment, we determine the zones of maxi-
mum offense and the sectors of minimum offense ; in the case,
however, in which it is not required that the offense of several
ships shall converge upon one and the same target.
When this last condition is established, it must be borne in
mind that, beyond a certain limit, the greater the number of ships
that take part in the concentration, the smaller is the effect of
the firing.
This diminution of effect cannot be considered if the concen-
tration is evidently imposed by special conditions of position ; but,
in general, it is necessary to limit the number of ships destined
to fire at one and the same target.
There is no difficulty in admitting that the fire of three or four
ships may be concentrated. Without entering into the methods
for the control of the firing during concentration, one datum to be
remembered is that Togo, who at Tsushima had 12 armored
ships, has written in his report that he concentrated his fire upon
two of the enemy's units; hence it seems permissible to believe
in the concentration of the fire of six units also, and, without
experience to the contrary, it is well to hold this number of units
to be the maximum.
On this basis, in the case of the concentration of the fire, it is
well to consider the alignment as divided into elementary parts.
The Fundamentals of Naval Tactics.
each having the length (n—i)d; n being a number of ships not
greater than six. AA' (Fig. 5a) being one of these parts, we
form the triangle AA'N, wherein NAA' = €=is°, and N indi-
cates the position of a hostile- ship at a distance r=NA from the
most distant point of AA'. Indicating by /? the angle NA'X'
formed by NA' with the prolongation of the alignment, it is clear
that the lines s^, s^, s^, s^, drawn from A and A', making angles
j8 with AX and A'X' respectively, determine the zones of maxi-
mum ofifense for the supposed value of r.
With a value of r anywhere between 10,000 meters and 6000
meters, yS is about 20°; and the difference r— / is about 2000
meters (r' being the distance of N from the nearest point of
AA').
14. Concentration and Distribution of the Fire. — Let us sup-
pose that one of the combatant parties, which we will indicate
by C, concentrates his offense ; while the other, which we
will call R, directs the offense of each ship against a ship of the
adversary. The party C secures tactical and strategical advan-
tages, because R is hampered in his movements owing to one of
his units having the sum of all the injuries that, on the other
hand, are distributed among the different units of C. It would
then appear logical to establish the concentration of fire as a
tactical objective, executing this concentration successively upon
the various units of the enemy, changing the object of concentra-
tion whenever one is put out of action. Thus, one group of ships,
with respect to another hostile group, should concentrate the
offense upon one ship ; and several groups should endeavor to con-
centrate their offense upon one and the same group of the enemy.
This seems to be confirmed by history. Indeed, the objective
of the two greatest tacticians of the sailing period, Suffren and
Nelson, was the concentration of forces ; it must be remembered,
however, that they attacked a part of the enemy's line, relying
upon overcoming it before the remainder of the forces could
come to its aid. This reliance was justified: (i) by the slow-
ness of the movements of the sailing ship ; (2) because the fight-
ing could not be efficacious unless the vessels came broadside to
broadside with those of the enemy. It resulted from this that
the forces not attacked were placed under conditions of non-
offense for a time sufficient to secure decisive results.
Naturally, the advisability of concentration is indisputable
29
The Fundamentals of Naval Tactics.
to-day as in the past, when we have conditions of position anal-
ogous to those pointed out ; or when the part of the enemy against
which the offense is not directed is in a position of inability to
offer offense; that is, when our own forces are in a sector of
minimum offense of the enemy's alignment. The analogy also
exists when a part of the enemy's force is so distant with respect
to the remainder as to offer a sensibly less efficacious offense. In
other words, the advisability of concentration is clear when, with
respect to the enemy, we have an advantageous position.
Definitions. — When an alignment has not the advantage of
being in a sector of minimum offense of the enemy, it may be
said that, with respect to the said enemy, its positon is tactically
advantageous, or equivalent, or disadvantageous, according as —
supposing the enemy's offense to be concentrated in the best man-
ner — it permits of executing the firing at distances less than, equal
to, or greater than those at which the enemy fires.
With equivalent alignments it must be remembered that, in
concentrating the offense, the ships at which we do not fire are
in conditions of tranquilit]' ; and hence there exists the advis-
ability of distributing the fire, because the offense offered is also
a reciprocal function of the offense received.
This last advisability cannot be considered when the distance
exceeds a certain limit, which it seems should be placed at 8000
meters ; in such case concentration becomes a necessity, to the
end that the offense may be efficacious, and its results may quickly
be tangible ; and this, remembering that, as the distance increases,
the probability of hitting rapidly diminishes.
Under such conditions it is then indispensable to prescribe that
the ships of one and the same group (taking into account the
limits pointed out in the preceding section) shall concentrate
their fire upon one of the enemy's ships ; this, however, does not
imply the advisability of two groups of ships having for objects
of concentration two hostile units forming part of the same
group, when our own groups are not in a sensibly advantageous
position with respect to the enemy's groups. Indeed, the con-
venience of distributing the fire must here be considered anal-
ogously to what has been set forth above ; besides, the tactical
necessity of dividing the ships into groups according to the
standard of homogeneity is evident. So, then, having two units
damaged in one of these groups, a combatant has his maneuver-
30
The Fundamentals of Naval Tactics.
ing qualities reduced in that group only; while, if the damaged
unit's form parts of two different groups, the maneuvering quali-
ties of the whole fleet undergo a reduction notably greater.
In conclusion, we may formulate the following general criteria,
the application of which is naturally subordinated to the neces-
sity of not often changing the objective that it is sought to
secure :
(i) At the maximum fighting distances it is necessary for the
ships of each single group to concentrate their fire.
(2) When the distance is below a certain limit (8000 meters),
it is best to distribute the fire, unless one has a sensible advantage
of position, sufficient to render concentration advisable.
(3) In concentrating the fire from equivalent positions, the
enemy's ships which are the object of concentration should prefer-
■ ably belong to different groups.
ELEMENTARY ALIGNMENTS.
15. The Ship Upon Which to Concentrate. — For the analysis
of the advantages of position, let us refer, first of all, to the
hypothesis of elementary alignments; or to simple, rectilinear
alignments of a length not exceeding 2500 meters, necessary for
six ships placed at intervals of 500 meters. At the present time
this distance is to be considered as normal, by reason of the high
speed and the dimensions of the battle units. From what has
been noted in section 13, it is possible to concentrate the fire of
all the ships of the alignment upon a single enemy's ship.
When not otherwise indicated it will be understood that the
length of the adversary's alignment is supposed to be the same.
The natural target for each ship is evidently the nearest; or,
it is that which is found at the foot of a perpendicular dropped
from the ship upon the enemy's alignment. It follows from this
that, except under special circumstances, the most opportune ship
for the concentration of fire must be held to be the one that is
nearest' to the center of the projection of our alignment upon that
of the enemy.
It is also necessary to take into account the importance of
continuity in the concentration of the offense. From this results
the advisability that the enemy's ship upon which the fire is con-
centrated should be at an extremity of the alignment; which,
31
The Fundamentals of Naval Tactics.
in its turn, we shall see confirmed when we come to discuss the
maneuvering.
We establish, then, that in general the enemy's ship for con-
centration should be the extreme one which occupies the position
nearest the center of the projection of our alignment ; or, such
ship is the extreme one on the side on which the inclination of the
enemy's alignment is less than po".
By this rule we may determine the ship for concentration,
unless the inclination of the enemy's alignment to the line joining
the centers is 90°. There may then arise two cases: (i) Our
own alignment is also normal to the line joining the centers. (2)
Our alignment is not inclined 90".
In the first case it evidently makes no difference upon which
extremity of the enemy's alignment we concentrate.*
In the second case, firing upon the extremity which is toward
the point where the alignments converge, it is discovered that,
with respect to the other extremity, the limits between which the
firing distances are included are wider. Moreover, it may not
always be possible to concentrate the offense upon the aforesaid
extremity, which may be in a sector of minimum, offense ; while a
certain advantage in fire control may result the more nearly we
approximate to uniformity of distance. In any event, in the case
to which we now have reference, the proper extremity is not
precisely designated by the conditions of distance, and hence is
selected on the basis of the objectives of the maneuvering.
16. Inclination. — It is easy to discover (see Fig. 6) that, to an
alignment, A^A^, normal to the line joining its center Ca vsrith
the center Cn of the enemy's alignment, N^N^, we can oppose
only an equivalent, or a disadvantageous alignment. In fact the
party N may have an alignment normal to CaCn, and then the
* It is to be noted that if we were to concentrate the fire upon the
enemy's center, rather than on an extremity, the firing distances would
not be sensibly different. Calling r the distance between the centers, rm
the mean firing distance, for alignments 2500 meters long, we obtain the
following :
Values of rm.
r Firing on the center. Firing on an extremity.
8000 meters 8045 meters 8200 meters
6000 meters 6065 meters 6250 meters
(Author's note.)
32
The Fundamentals of Naval Tactics.
alignments are equivalent; or, it may assume an alignment dif-
ferently inclined, as in the figure. In the latter case, from what
has been said in the preceding section, the ship for the concentra-
tion of the A party is A^^ ; and that for N is A^, it being supposed
that the angle N^Cy,Cj, is not too small. Drawing from N^ the
perpendicular N^Pj, to A^A^, the firing distances for A are be-
tween PiA/'i and A^N^; and those for N are between N^A^ and
N,A,.
We have
N^A,>P^N^.
The two triangles N^N^A^ and A^N^A^ have the side N^^A^^
in common; the sides N^N^ and A^A^ are equal; the angle
--^4.
^x;;
O.^
Fig. 6.
N^N-^A^ is obtuse, while N^A^A^ is acute ; hence
N^A^>A^N^.
Analogously it is demonstrated that the firing distances of N
are also greater than those of A when the firing is concentrated
upon A^.
The alignment of the party N is therefore a disadvantageous
one, conformably to the proposition enunciated; from which we
quickly draw the following deductions : ( i ) If the enemy's
alignment is not normal to the line joining the centers, our assum-
ing an alignment normal to the said joining line places us in an
advantageous situation. (2) Of the two alignments, the situa-
tion of the one whose inclination to the line joining the centers is
nearest to 90°, is the most advantageous. (3) With equal in-
clinations to the said joining line there is equivalence. It is worth
while to note that, when this is realized, the angles that the lines
33
The Fundamentals of Naval Tactics.
joining the corresponding vessels make with their directions are
equal.
The inclination to the line joining the centers generally con-
stitutes the best guide for estimating the advantages of position.
Definitions. — To the position of the alignment inclined to 90° to
the line joining the centers we give the name of fundamental
tactical position.
We say that an alignment crosses the T (or is in position to T)
when it is in the enemy's sector of minimum offense.
For crossing the T, that inclination which permits having the
minimum firing distances, would seem to be the best; in other
words, in penetrating into the enemy's sector of minimum offense,
it would be necessary to incline our alignment, at the extremity
nearest that of the enemy, as far as the limit of his zone of maxi-
mum offense. Let us consider (Fig. 7) wherein p=^XAJS!-^
= YN^Ar^ is the angle of which mention was made in section 13 ;
this hows an alignment of A that crosses the T. The alignment
A''iA'^2 may still fire upon A^, but A is in- a momentary situation
that is very advantageous, because its firing distances, putting
r^N-^A^, are practically included within the limits, r and r— 2000 ;
while for N, the distances are between the limits, r and r-|-2000.
But, in order to escape from this disadvantageous position, it
is enough for the party N to rotate his alignment in a way which
will permit him to fire upon A.^ ; in other words, in order that the
positions may be equivalent, it is sufficient for the party A'' to
rotate his alignment through the angle N^NJ>J\ = A2NyA^; a
greater rotation produces an advantage for N.
It is seen, then, how easy it is to eliminate the advantage of A
when the T is crossed in the manner indicated ; it is well, there-
fore, to seek to secure an advantage which, although smaller,
may be maintained for a longer time. It is evident that the posi-
tion of N will be so much the longer defective, the greater the
amplitude of the rotation necessary to establish equivalence. It
results from this that the advantageous alignment for crossing
the T is the fundamental one, A^F.
It is clear that, with alignments of different lengths, the shorter
one is in a theoretically advantageous position, not only when,
with respect to the enemy, it has an inclination nearer the funda-
mental one, but also, when it has an inclination equal to that of
the enemy.
34
The Fundamentals of Naval Tactics.
In the practical cases, the difference in
length between two alignments that are a.
not very different in strength cannot be
very great. The difference in the number
of ships may be one or two ; and hence the
difference in length may be 500 or 1000
meters; and since only a small part of it
can affect the conditions of position, its
influence appears to be negligible.
17. Equidistant Positions. — In this part
of the subject, in studying the momentary
situations — ^although without entering into
an examination of the movements — it is
necessary to keep in mind as a guide the
practical object sought.
The deductions drawn in the preceding
section have real practical importance, be-
cause they permit us to estimate whether
it is better to change the alignment, and if
so, how.
Except in special cases, even if two ad-
versaries move, keeping their rectilinear
alignments unchanged, evidently their in- Fig. 7.
clination to the line joining their centers
changes. Since a rectilinear alignment cannot be instantly
changed, it appears necessary, as a complement to the deductions
just mentioned, to seek for a form of alignment that closely ap-
proximates to the fundamental one, and that, with respect to
the line joining the centers, can easily and continuously be
maintained.
To this we come with the following observations :
(i) An elementary alignment in the arc of a circle having for
its center an enemy's ship, may practically be considered as a
rectilinear alignment normal to the line joining its center with
the aforesaid enemy's ship.
(2) Two adjacent ships of an ahgnment may be said to be on
the arc of a circle having an enemy's ship for a center, when, for
each one, the straight lines joining them respectively with the
friendly ship and with the hostile ship, form an angle of about
90°.
N2N..
35
The Fundamentals of Naval Tactics.
(3) It is well known that the simultaneous change of course
of several ships must of necessity be successive at very short
intervals of time; each ship having to wait for the movement to
be begun by the ship next within, on the side toward which the
change is made. From this it follows that, in the tactical steering
of an elementary alignment, the extreme ships are to be con-
sidered as regulators ; inasmuch as we can conceive that, while
one of them completes the movements of the change of course
in a wide sweep, the others may imitate them in a continuous
manner, tending to maintain the parallelism of the courses. This
being the case, on the basis of the two preceding observations, it
appears advisable to consider what alignment is obtained if every
ship continually maneuvers with the criterion of considering itself
in position when the angle between the line joining it with the
Fig. 8.
adjacent ship on the side toward the regulator, and that joining it
with the enemy's ship of reference, is pO°.
The form of alignment is that indicated in Fig. 8 ; this form
is a broken equilateral one, with the inclination of its sides to the
radius vectors drawn from the pole N^ (the enemy's ship) equal
to 90°.
Distinguishing the units of the alignment by numbers from i
to 6 — No. I being the regulator ship — and indicating the re-
spective distances from A^o by r^, r^, . . . . r,, we have
2-r^2_^2,
'2
r^^ = r^ — d^ — r^ — 2d^,
With the customary value of ^=500 meters we obtain:
for ri = 8ooo meters, >-e = 7920 meters;
for ri = 6ooo meters, ro = 590o meters;
for ri = 4000 meters, ^,3 = 3840 meters.
36
The Fundamentals of Naval Tactics.
Within the limits of long-range battle — the difference r^ — r^
being thus absolutely negligible — the form of alignment that is
obtained in the manner above indicated may in effect be held to
be that on an arc of a circle, or at positions equidistant from N^ ;
and hence, by the first of the preceding observations, it consti-
tutes a rectlinear alignment normal to the line joining its center
with N^.
Such a form of alignment satisfies the requisites above speci-
fied ; in other words, if A^^ is the center of the enemy's alignment,
and we suppose that our forces have the fundamental tactical
position, this position thus appears to be susceptible of being
maintained.
Reserving it to ourselves to discuss in its turn this question
with regard to the maneuvering, we hold meanwhile that, in order
continually to tend to the securing of the advantages of position
pointed out in the preceding section, the alignment with equi-
distant positions with respect to the enemy's center will generally
appear to be advisable.
It is readily seen that if our force is outside of the zone in-
cluded between the perpendiculars to the enemy's alignment
drawn from its extremities, a sufficiently advantageous form of
alignment may be that with positions equidistant from the enemy's
nearest extremity; and it is so much the better, the nearer the
position of our center to the prolongation of the enemy's align-
ment.
i8. Composite Alignments. — Two contiguous elementary align-
ments, one on the prolongation of the other, constitute a com-
posite rectilinear alignment.
Two alignments of this kind opposed to each other, if of equal
length and equally inclined to the line joining the centers, are in
equivalent positions ; because, from what has been said in
sections 14 and 16, equivalence exists between the correspond-
ing elementary alignments. It is readily seen that, for a given
inclination to the enemy's alignment, the most advantageous posi-
tion for our own alignment (if the condition is imposed that it
be rectilinear) is the one normal to the line joining the centers;
because in this way, the single rectilinear alignments are in posi-
tions nearest that of the fundamental position.
The condition mentioned (rectilinear alignment) is, however,
neither necessary nor advisable. In regard to position, it is
37
The Fundamentals of Naval Tactics.
advantageous (and it is intuitively seen that it may be desirable
for elasticity of maneuvering) that each elementary alignment,
virhile respecting the bond of compactness, be left free to incline
itself in the most opportune manner. From this are derived
angular alignments, like that of Fig. 9, in v^rhich one elementary
alignment of A is normal to C'aC'n, and the other is normal to
aI-- N.
In practice, from what has been said concerning equidistant
positions, the angular alignment may be composed of arcs of
circles having their respective centers in convenient points of the
enemy's line.
M
Fig. 9.
As has been noted in section 14, when the inclination of the
enemy's alignment to CaCn differs notably from 90°, the concen-
tration of the offense of the two elementary alignments of A
upon two ships of the same elementary alignment of the enemy
is advisable ; in such case the alignment of A becomes nearly the
arc of a circle with its center in the middle of the said elementary
alignment of the enemy.
On account of the disadvantage of position and the manifest
difficulty of maneuvering which is encountered with alignments
of great length, the hypothesis of greater lengths than those that
are included in the two elementary alignments of six ships each,
is logically to be excluded.
19. Double Alignments. — The number of ships that can maneu-
ver in a single line being thus limited, in order to keep compact a
force of greater size, it is necessary to have recourse to an align-
38
The Fundamentals of Naval Tactics.
ment on two parallel lines, near to each other, so placing the
ships in the line on the side away from the enemy, that they may
fire through the intervals of the other line.
When the fleet is not very numerous, it seems logical to make
use of such an expedient for reducing the length of the alignment.
It is observed, furthermore, that a group of antiquated ships,
and ships deficient in protection, but yet having good speed, such
as not to embarrass the tactical and strategical control of the
fleet, may represent an element of offensive power that can use-
fully be employed against an enemy's armored fleet. In order to
employ such ships, safeguarding them in order to prevent the
enemy from bringing about their loss by means of a brief con-
centration of force, which would produce serious moral effects,
one of two systems worthy of consideration is that of placing the
said ships, so as to enable them to fire through the intervals of
the other line. Thus we have a third case in which the double
alignment may be of use.
Evidently, for such alignments, there exists the importance of
the fundamental position ; that is to say, there exist the principles
deduced in the preceding section for simple alignments.
It is intuitively perceived, however, that, with this form of
alignment, besides rendering it possible for the enemy to launch
torpedoes from long distances with a certain possibility of hit-
ting — as has been noted in the preceding chapter — we encounter
other notable inconveniences with respect to a simple alignment.
(i) Diminution of the maneuvering qualities of the fleet;
difficulty of taking up angular alignments.
(2) Increase of the amplitude of the sectors of minimum
offense.
With the first of the inconveniences mentioned we shall occupy
ourselves in Part II of our study. In order to estimate the
second, we observe that, in order to fire in the intervals between
the ships of the inner line, the limit of approach to the ships of
the inner line by the ships of the outer line is naturally deter-
mined by the condition that the distance between ships shall not
fall below the normal distance of 500 meters.
This being understood, let us determine the amplitude of the
sectors of minimum offense of an elementary double alignment
ahc, ciVd (Fig. 10), composed of six ships in a manner anal-
ogous to that which was used in section 13 for a simple alignment.
39
The Fundamentals of Naval Tactics.
Let us consider the triangle aba', formed by two ships, a and b,
of the inner line, and by of, which fires through their interval.
From what has been said in section 13, the position of of is the
limit position which permits offense in the direction of the align-
ment cba when there is realized
where (45° forward of and abaft the beam being the amplitude
of the sectors of maximum offense of the ships under considera-
d
ei)
ib'
Fig. 10.
Fir. II.
tion, and L the length of said ships) the angles e^ and i^ are
deduced from the equations (section 13)
L .
sinfi=-^sin 45 ,
L .
sin t2= ^ , sm 45 .
aa
To the end that the offense may converge upon a single target,
the value of ba'a must be somewhat greater than that above men-
tioned. It is found by trials that the limit position of a' (which
determines those of b' and c') may be held to be reached when
40
The Fundamentals of Naval Tactics.
ba' = a'c = d; consequently, indicating by (8 (as in section 13) the
half amplitude of the sector of minimum offense of the double
alignment, we have )8 = 6o° — 15°=45° (about), to be compared
with the value ^8 = 20° obtained under the hypothesis of the
simple alignment.
On account of the inconveniences pointed out, it seems logical
to affirm that the double alignment is not to be adopted except in
case of absolute necessity.
20. Groups. — We will now consider the hypothesis that the
parties A and N, opposed to each other, are of the same strength
and each formed by two elementary alignments, which, for the
party A, are separated into the groups A' and A"; while N has
his forces compact and on a simple alignment.
In Fig. II we indicate by A' and A" the positions of the centers
of the respective groups, the alignments of which we suppose to
be in the fundamental positions with respect to the nearest ele-
mentary alignment oi N.
If A' and A" are at the same distance from Cn, the party N, by
assuming an angular alignment with the sides respectively nor-
mal to A'C'ti and A"C"n, places itself in a position of tactical
equivalence.
If A' and A" are at sensibly different distances from Cn, the
party N may assume an opportune alignment with respect to the
nearest group and concentrate the offense on two of its ships;
in this way the situation of N is advantageous. Moreover, when
the angle A'Cj^A" exceeds 90°, it may befall that the party N
can utilize the guns on both sides. It is therefore necessary to
bear in mind that while in the sailing period the concentration
had logically to be sought by placing the enemy between two
fires, to-day the opposite is important. Naturally this considera-
tion has no importance in case the party AT' is entirely made up of
ships all of the principal guns of which have a field of fire on
both sides.
In general it rnay be understood that the position of the com-
pact fleet is so much the more advantageous the nearer it is to the
line joining the groups (externally or internally).
From what has been said it results that, for the party having
compact forces, we may assume conditions of equivalence and
also of superiority, with respect to the other that is broken up
into groups. Under the hypothesis considered, the advisability
41
The Fundamentals of Naval Tactics.
of this last system is not excluded by this, but it is important to
hold: (i) that such advisability is to be considered only in
regard to the maneuvering; (2) that an echelon of groups in
distance would be dangerous.
II. We will now consider the hypothesis that the forces oppos-
ing each other are equal, and that each party is so numerous that,
in order to be compact, recourse must be had to the double align-
ment. In order to eliminate the inconveniences pointed out in
the preceding section, it is possibly proper to prefer the separation
of the forces into two divisions in simple alignment. In Part II
we shall consider when the impossibility of doing so exists, or
under what relative conditions of mobility maneuvering by groups
may expose one to serious risks.
Setting aside the case in which the conditions just mentioned
impose the double alignment, this may be advisable when the
number of battleships at one's disposition is greater than that
with which two groups may be formed in simple alignment; in
fact it is well to note that the greater the number of groups, the
smaller is the probability timi their mMvem^nts may be co-or-
dinated; and hence, in general, it seems advisable not to form
more than two groups (exceptionally three), even at the cost of
having recourse to the double alignment.
III. It is to be held as an axiom that, in general, it is not well
to divide the fleet into groups of the same importance ; rather
than have two groups, both of them of small manageability, it is
preferable to decide that one of them shall be endowed with
special aptitude for the acquisition of advantageous positions.
We reserve it to ourselves to develop, in its turn, this idea of the
division of the forces into a principcd squadron and a Hying
squadron.
Summing up, when fleets about equal in strength and not very
numerous are opposed to each other, the breaking up into groups
can only be advisable in order to obtain the maximum freedom of
maneuvering; for numerous fleets, this expedient appears to be
preferable to the double alignment. When the breaking up into
groups is not rendered necessary simply by this numerical cause,
the idea that prompts it may be that of attempting enveloping
movements (crossing the T) by means of a flying squadron.
On the basis of the ideas advanced, the discussion of the hy-
pothesis that both the adversaries are divided into groups is
evidently simple.
42
The Fundamentals of Naval Tactics.
In order that the battle may resolve itself into partial actions
between single groups, this would have to be the purpose of both
the adversaries. Rut, as it is logical to endeavor to concentrate
the action of two groups upon a single enemy's group, the
advantageous alignment (keeping in mind the relative definition
of section 12) appears, in this case also, to be the fundamental
one ; while the echelon of groups in distance is disadvantageous
unless the enemy adopts the same system.
21. Natural Elements. — In determining the advantages of posi-
tion of two adversaries many elements enter into the account
besides the situation of the respective alignments ; as, for in-
stance, the natural elements (sea, wind and sun), as well as the
conditions of position with respect to the coast and to the strate-
gic objectives.
Concerning the importance to be attributed to these elements it
would be vain to pretend to formulate well-defined rules ; it is
clear that the values that may be given to them are to be sub-
ordinated to the necessity of having an opportune alignment in
the respects already pointed out; and that holding it bound
by too many conditions, signifies the creation of useless shackles.
On this account we shall take only a rapid survey of the aforesaid
elements.
With the sea greatly agitated, the difficulties of firing are very
great ; the combat may be reduced to a useless waste of amhiuni-
tion, or, if there are decisive effects, the case itself may have
much to do with them. Nevertheless, this does not mean that we
are only to fight with a smooth sea; even with a rough sea an
admiral will seek to oblige an enemy to fight if it is rendered
necessary by the strategic situation ; in which case, it is possibly
well to avoid presenting the beam to the sea, diminishing in this
way the difficulties of firing and the risk of receiving shots below
the water-line. It must be remembered, however, that the gun-
ners must be accustomed to firing under any conditions whatso-
ever. The situation of a fleet that, in order to obtain good fire
control, would be obliged excessively to hamper the maneuvering
would be a sad one.
With a fresh wind in the direction of the plane of fire it is
doubtful whether it is better to fight with the lee side in action or
with the weather side. In the first case, at high speeds, the
smoke issuing from the funnels renders the firing difficult ; in the
second, the smoke and the powder gases are driven back into the
43
The Fundamentals of Naval Tactics.
turrets and casemates, the occurrence of flarebacks is favored,
and the lenses of the telescopic sights may be dulled by spray.
Pros and cons also exist if we consider the direction of the wind
with respect to the course of the ship. A wind that blows in
the direction of the longitudinal axis envelops the range finders
and the observers in the tops in smoke. If the wind comes from
ahead, with a fleet in column of vessels, each ship is enveloped in
the smoke of the preceding one. If the wind comes from astern,
the smoke hangs over the ships a long time. It seems, then, that
it may be advisable to maneuver without troubling oneself about
the wind. Only a ship that has the defect of having guns but
little elevated above the sea could have much interest in keeping
to windward of the enemy.
The direction of the solar rays may have considerable impor-
tance when the sun is only a little above the horizon, because, not-
withstanding the colored glasses on the telescopic sights, having
to fire with the sun in one's eyes is a grave inconvenience. It is
logical to seek to escape from this situation by rotating the line
joining one with the adversary in a way that tends to bring the
sun at one's back. When the sun's rays make a considerable
angle with the plane of fire the aforesaid inconvenience is negli-
gible.
It is well known that the target can better be seen when it is
projected upon the horizon rather than upon a coast; it may then
be desirable to be between the enemy and the coast, whenever,
naturally, the neighborhood of the latter does not interfere with
the liberty of maneuvering.
Finally, it is clear that the position of the adversaries consid-
ered with regard to strategic centers may be of importance; but
this cannot justify long maneuvering out of range, which may
cause the risk of losing an opportune occasion for fighting. The
candid truth which history shows us is not always remembered,
is that the issue of the war depends upon the battles.
CHAPTER IV.
The Fighting Distance.
22. Uniformity of Distance. — The problem which we propose
for ourselves is that of establishing the criteria proper for deter-
mining the most convenient fighting distance, or the distance of
maximum utilization.
44
The Fundamentals of Naval Tactics.
First of all, it is well to discard two methods that may be at-
tractive on account of their facility for furnishing a result ; for
this purpose let us refer to the simplest hypothesis, that is, of
the naval duel.
(i) We might seek the solution by calculating the difference
that exists between the two adversaries in the total energy de-
veloped by the projectiles on impact. The distance correspond-
ing to the most advantageous value of the said difference would
be the distance required. It is clear that such a method would be
absurd, since there exists no equivalence of effects with equality
of dynames * developed by the different kinds of guns. Aside
from this, the method would evidently be one-sided.
(2) We might place the penetrating power of the guns of each
combatant in comparison with the thickness of the enemy's armor.
But, in this comparison, what shall we hold to be the inclination
to the plane of fire? Let us suppose our ship to be at a distance
r from the enemy, who is able to pierce the side armor, when the
ship presents her beam, with a projectile that, at the above men-
tioned distance, has a residual velocity v. If, while remaining
at the distance r our ship assumes the inclination i^ to the plane
of fire (counted from the beam), from what has been said in
section 4 (Chapter I), this is equivalent, from the defensive
point of view, to being placed at the distance at which the
residual velocity of the aforesaid projectile is v cos h^li (where
h=i) ; the offensive power, however, remains constant unless
the direction i/r is outside of a sector of maximum offense. It is
easy to prove that even a moderate value of i/' is equivalent to a
material change of distance, which is all the greater the greater
is the caliber. Hence, the inclination to the plane of fire cannot
be overlooked. Wishing to apply the above-mentioned method,
it would logically be necessary to suppose that the adversaries
have each other bearing in directions of maximum utilization;
then, however, no conclusive result could be reached with ships
having large extensions of armor with thicknesses not below 150
millimeters.
In any event, the method which we are discussing would also
be one-sided, because, while considering the defensive element
(neglected in the foregoing) we should set aside most important
elements, to which we will allude.
* Dyname = 1000 kilogrammeters. (Translator's note.)
45
The Fundamentals of Naval Tactics.
Methods of the nature above mentioned, even if they could fur-
nish results logically worthy of consideration in the case of two
ships opposing each other, or of two groups composed of homo-
geneous ships, would not be applicable to the case of fleets com-
posed of groups of ships of different types. In fact, these results
would be very different for the various types, and then the legiti-
mate consequence of such methods would be to make the various
parts of the fleet fight as independent groups, echeloned at dif-
ferent distances from the enemy. So, then, aside from the possi-
bility of always adopting the system of maneuvering by groups,
we cannot admit the advisability of the echelon in distance for
reasons discussed in section 20; on the contrary, we derive from
it that the idea to be assumed as fundamental is that of the neces-
sity of having the varioitrS parts of our fleet fight under conditions
of a uniform mean distance.
In comparison with the system of the echelon, which might
give to the tactical employment of the forces a rigidly prearranged
form, the idea just enunciated appears the more rational inas-
much as, with it, we at once perceive the possibility of regulating
the development of the tactical action.
In virtue of this idea, the question to be discussed appears
complex ; and it is proper to add that the complexity does not
depend solely upon the heterogeneity of the different divisions
of the fleet. Indeed, the variables of the problem do not reduce
to the weapons and to the protection, but we must take into ac-
count strategic factors, and others of a moral and organic nature.
23. The Strategic Situation and the Fighting Distance. — The
axiom with which we closed the preceding chapter must be re-
called here: The war is decided by means of decisive battles.
Ought we to draw from this the corollary that every tactical
action must be pushed to a finish, or that, unless it is developed
to the point of obtaining the destruction of the enemy's forces, it
is unprofitable ?
The question is prejudicial to the subject we have under dis-
cussion, since, if the reply is in the negative, on that basis it may
sometimes be well for the fighting distance not to fall below a
certain limit.
To overcome the enemy is the desire of all who fight, but in
some cases a tactical victory may be a strategic defeat. Some
particular examples are necessary in order not to be misunderstood.
46
The Fundamentals of Naval Tactics.
During the first period of the recent war, up to the fall of Port
Arthur, the Japanese had to consider that, while the whole of
their force was engaged, the enemy, even after the destruction
of the first squadron in the Pacific, would be able to send a second
squadron from the Baltic. Italy, in case of a war with France,
given the present relative conditions of the naval forces, might be
found to have a superiority with respect to one fraction of the
enemy ; we shall, however, have to consider that, if in the victory
our forces sustain such injuries as to remain for a long time
paralyzed, ours would be a Pyrrhic victory, because the adver-
sary, although having had one of his fractions annihilated, will
have acquired liberty of action with the remainder.
On the other hand, at Tsushima, Japan found herself obliged
to seek the annihilation of the enemy, because that signified the
complete solution of the martime struggle. Italy against Austria
would have to seek to end the struggle by one decisive battle,
because, supposing that we have a total superiority of forces,
every elimination of equal forces would be to our advantage.
England, given the necessity of keeping open her commercial
communications, and given also the development of her forces,
would have to seek the destruction of the enemy. These ex-
amples demonstrate that the axiom which establishes that the
object of fighting- is to overcome the enemy, admits as a corollary,
not the unconditional advisability of a decisive struggle, but the
necessity of pushing the tight as fa/r toward a finish as is per-
mitted by the strategic conditions.
To establish firmly this postulate, it is necessary to examine the
doubts that may be formulated on the basis of the principles of
war on land and of naval history.
In the history of war on land it is set down as incontrovertible
that the shock of grand masses should be of an exterminating
character. To deny this would be to signify the return — as
Clausewitz wrote : * — " To the systems of warfare that preceded
the Revolution and the French Empire, in which there were
manifested the falsest tendencies, pretending to aggrandize the
military art the more war was deprived of the use of the only
means proper to it: the annihilation of the enemy's forces."
Such false tendencies consisted " in the pretension of the possi-
bility, by directly seeking only a limited destruction of the forces
* Teoria della grande guerra. Vol. I.
47
The Fundamentals of Naval Tactics.
of the enemy, of arriving, by way of wise combinations, at his
complete direct enfeeblement ; or, in other words, of exercising,
by means of small blows ably administered, such an influence
over his will as to lead him the more promptly to submit
The direct destruction of the armed forces of the enemy must
stand before every other consideration."
We observe that in affirming the possibility of having, in naval
battle, to consider also the stretegic situation, we have not denied
the correctness of the axiom concerning annihilation ; we have
only expressed a reserve under the hypothesis that, after the
hostile naval forces that we have confronting us, we must keep
ourselves in condition to meet others of them, having at our
disposal only our present forces ; or under the other hypothesis
that we have already confronting us the entire forces of the
enemy, but we, on our part, have not a sufficient force to give
us the probability of victory in a decisive battle ; it may be a case
of delaying the battle until the moment in which the enemy offers
so vital an offense as to oblige us to stake all against all.
The comparison, then, must begin by being made with the
situation of an army, A, which has confronting it a hostile army,
Bi, about equal in strength; and which forsees having after-
wards to fight also another army B^. The question to be pro-
pounded is this : Does there exist for A the possibility of push-
ing the fight with B^ to a finish, and of afterwards finding
himself still in condition to oppose B^ ? Evidently the reply may be
in the affirmative ; the annihilation of B^ may bring great loss to
A, which, no matter how great, may not be so important a frac-
tion of the total as to produce incapacity to oppose B^ ; the moral
advantage acquired will be so great as largely to compensate for
the said loss ; and then, it will perhaps be possible to fill up the
vacancies by drawing upon the great resources in men that
modern states possess, given the national character of the wars.
At sea, under analogous conditions, the struggle against B^ —
given the fact that it is victorious — if it has been a fight to a
finish, will inevitably have caused serious losses which" will either
not be reparable, or will not be so in sufficient time ; in other
words, either we shall have lost ships, or we shall have them so
seriously damaged as not to be able to count upon them when
we have need of them.
The difference between the land and the sea depends essentially
The Fundamentals of Naval Tactics.
upon the fact that on land it is a struggle of men ; at sea it is A
struggle of ships. On land, numbers constitute a great factor;
at sea we have only a very limited number of units, and every
elimination means the loss of an important fraction of the total.
On land, given the nature of the means, we are able to imagine
only the fight to a finish or the barren struggle. The same was
the case at sea during the sailing period — ^the condition of the
means of war did not permit of efficacy except when fighting at
close quarters. Under such conditions, the principle that the
battle must be pushed to the annihilation of the enemy was a
necessity; when the conservation of the forces was imposed, it
was necessary to keep them in a potential state, just as, on land,
in an analogous case, there was imposed the necessity of taking
a flank position. Great admirals are not wanting to give us
examples of this — it will suffice to cite some typical cases.
In 1673, Ruyter maintains himself in a state of efficiency behind
the banks of Schoneveldt, because his fleet is inferior to that of
the Anglo-French; in this way he conserves his forces until the
time when Holland is threatened with invasion. In the war of
1778, Howe, owing to the inferiority of his forces with respect
to those of d'Estaing, upon news of the arrival of the latter on
the American coast, leaves the Delaware in order not to be
obliged to fight under unfavorable conditions, and goes to take
part in the defense of New York, in a position where the enemy
does not dare to attack him. And when d'Estaing goes to sup-
port the troops of Washington in the attack on Newport, Howe
goes promptly in advance to Rhode Island where, on account of
the prevailing winds, he reckons upon keeping to windward, or
launching fire ships if the enemy remains in the bay. The pres-
ence of Howe puts d'Estaing in a critical position, and therefore
the French squadron profits by a favorable wind to leave the
anchorage, thus abandoning Washington to himself. As Mahan
observes, " the weaker fleet has fully beaten the stronger by
virtue of its maneuvers."
To-day, the fact to be borne in mind is that long-range battle
has acquired greater efficacy than in the past; and from this it
follows that by keeping the development of the action within
certain limits, it may be profitable to engage tactically, not only
in situations analogous to those in which battle was advisable
during the sailing period, but also, in part, in others in which it
49
The Fundamentals of Naval Tactics.
was then necessary to remain in a state of efficiency. It must,
then, be acknowledged that, the conduct of the forces being in-
spired by the postulate which we support, as against the other
which expresses the necessity of engaging only under conditions
of being able to seek the destruction of the enemy, we shall have
an increase and not a diminution of the offeiisive spirit.
We proceed, then, to seek the solution of the proposed problem
on the basis of the idea that the strategic situation may limit the
development of the tactical action, as long as we have more in-
terest than the enemy in the conservation of the forces; while
under the contrary hypothesis, it is important to press the fight
to its decisive phase; which naturally does not signify that it is
well to close the distance from the beginning.
24. Tactical Zones. — If the problem could be solved with
methods of the kind mentioned in section 22 — that is, on the
basis of numerical calculations — it might be possible to give to
the distance of maximum utilization a strictly determined value.
But the variables to be considered are such that we are not able
to reach a really logical result except by dividing the tactical
field into zones of considerable width, and examining, with re-
spect to the zones, the benefits that the two opposed parties can
derive from the action. At the present time the subdivision that
seems reasonable is the following :
1st zone, distances from 10,000 to 8000 meters (extreme range).
2d zone, distances from 8,000 to 5000 meters (long range).
3d zone, distances from 5,000 to 3500 meters (medium range).
4th zone, distances from 3,500 to 2000 meters (close range).
5th zone, distances less than 2000 meters (close quarters).
The heavy-caliber gun is the weapon of the first two zones;
therein the medium guns are of use for the improvement of the
firing and for action against unprotected parts ; beginning at the
upper limit of the second zone these guns begin to give notably
good results. In the third zone the probability of hitting with
the medium guns is sufficient for assigning a special value to
their action. In the fourth zone, from what has been said in
Chapter II, the employment of the torpedo is possible. In the
fifth zone it is also necessary to take into account the possibility
of collision; its limit being assigned according to a criterion of
which we shall speak in Part II.
25. The Initial Advantage. — A first datum concerning the rela-
tive importance to be attributed to the different zones is found
50
The Fundamentals of Naval Tactics.
in the following axiom : It is of the highest importance to obtain
an initial advantage, because it has a compound influence ; that is,
it tends to increase the advantage, not only by reason of the
material injuries which diminish the enemy's offensive capacity,
but also because it produces moral injury and disorder.* In
virtue of this, as has already been realized in the Russo-Japanese
war, there may be felt by the winner a relative safety which is
surprising.
The initial advantage may profitably be sought, especially in
the first two tactical zones, because in them full allowance may
be made for exercising control over the fleet ; while the further
we advance into the successive zones, the more we are under the
sway of the unforeseen which reigns supreme at close quarters.
In other words, it is to be held that a struggle at extreme or at
long range constitutes an efficacious means of preparation for the
struggle at medium or at close range.
On the basis of the principle thus established, we may be in-
duced to seek battle in the zones within the second by an initial
disadvantage, experienced or anticipated. Let us fix the ideas in
this connection.
The shorter the distance, the greater is the percentage of
effective hits for both the adversaries ; but may this variation be
considered the same for both? Evidently, no; the difference
depends upon individual ability, upon the means at one's disposal,
and upon the fire control.
The difference dependent upon the gun laying varies with the
firing distance ; in fact, at short distances, even a mediocre gun
layer fires well; the difference in ability between two gun layers
always makes itself the more felt as the distance increases, and
when the ship is subjected to rolling movements. So, also, the
* " D'un cote, le commandement, deseperant du succes, tombera dans
Vhesitation ; il songera a sauver les debris de sa fortune; la direction
deviendra incertain ; I'artillerie, precipitant son tir pour rattraper I'avantage,
gachera ses munitions; les officiers seront impuissants a diriger leurs
hommes.
" De I'autre cote, le spectacle sera tout different au debut de Taction, le
courage n'est soutenu que par une effort de la volonte qui enleve a chacun
une partie de ses facultes ; mais aussitot qu'on eprouve I'impression que
I'ennemi commence a ceder, une detente se produit ; la confiance succede a
I'apprehension. Chacun reprend son sangfroid; le combat devient plus
methodique Des lors la victoire est assuree." — Daveluy.
SI
The Fundamentals of Naval Tactics.
greater the distance, the more the ability of the directors of the
firing affects the results.
With equal ability of the personnel, the better are our range
tables, the greater the homogeneity of the armaments of our
ships, and the better the state of our weapons, so much the more
may we have confidence in being able to adjust the firing before
the enemy can do so, or, to secure the initial advantage.
But, a priori, the elements just pointed out are almost entirely
imponderable; the above-mentioned differences will have effective
influence, but they cannot be estimated beforehand. Generally,
then, at the beginning of the combat, each of the adversaries will
be confident of securing the initial advantage; consequently, if
the one who can impose the distance (in the manner which we
shall consider in Part II) has greater interest than his adversary
in the conservation of the forces (section 23), the action will he
limited to this phase; otherwise, it will consist of successive phases;
hut a phase in the first two zones is logically to he predicted, ex-
cept in the cases which we will now point out.
The arguments that can be deduced for maintaining that, with-
out initial disadvantage, battle in the third and fourth zones may
be expedient from the beginning, are the following :
(i) Inability to perforate the enemy's armor in the first two
zones.
(2) The short life of the heavy guns.
It is to be observed that in the recent war the possibility of
obtaining important tactical results, even without the effects of
perforation, may have been demonstrated.
The importance of the initial advantage being admitted, given
the fact that fighting at long range may serve a very useful pur-
pose in preparing for the struggle at shorter distances, should
we renounce it on account of the wear and tear to the heavy
guns derived therefrom? Given the fact that we are disposed to
risk the ships by closing the distance, why not also risk the guns
in battle in the first two zones? The arguments adduced must
be considered, but not by one of the adversaries alone ; we ought
not to preoccupy ourselves too much with the wear and tear of
the guns, because those of the enemy are worn out equally with
ours. It results from this that, while, on the one hand, in the
first encounter we fight at long range, closing in afterwards
according to circumstances, on the other hand, in continuing the
war, we might be obliged to fight initially at medium range.
S2
The Fundamentals of Naval Tactics.
It is well, however, to hold that, having more interest than the
enemy in the conservation of the forces, in order to be truly free
to choose the tactical zone it is necessary that the choice be per-
mitted by the state of the ammunition supply and the number of
guns in reserve, which must at least be equal to that of the enemy ;
an inferiority in this respect evidently may render it necessary
to seek to delay the battle until the strategic situation imposes a
fight to a finish.
At this point in the discussion, in order to assemble the ideas
concerning the interest that a belligerent may have in fighting
in one zone rather than in another, let us consider the problem
by parts ; examining the influence of differences in the means of
offense, and that of differences in the means of defense.
26. Differences in the Means of Offense. — Let us suppose that
there exists between the adversaries a difference in the number,
but equality in the kind of weapons.
If, with two opposed parties, A and B (ships or fleets), the
first has over the second the advantage of n guns of a certain
caliber, with equality in other conditions, the damage inflicted
upon B is roughly equal to that sustained by A, increased by that
which is produced by the n guns in advantage. Hence it is clear
that the difference in the number of weapons, with equality in the
kinds of the same, makes its effect the more felt the more the dis-
tance diminishes ; and for this reason, unless an inferiority is so
notable as to make it advisable to seek battle at close quarters, it
produces an interest in fighting at long range and seeking to
compensate for the disadvantage with dexterity.
Let us now suppose that A and B have guns of two kinds ; for
example, A has n-^ guns of heavy caliber more than B, while B
has Wj guns of medium caliber more than A. Diminishing the
distance increases the efficiency of n^ and n^ alike ; A, however,
is interested in not allowing the distance to fall below the inferior
limit of the zone in which the action of the heavy caliber is par-
ticularly efficacious ; hence, for A, the second zone is suitable,
while for B, the fourth zone is best, or the lower limit of the
third, when it is desired to exclude the use of the torpedo.
In relation to the criteria just enunciated, the following obser-
vations are to be made :
(i) A ship, the guns of which are not capable of yielding the
same return as those of the enemy (with equality in number and
S3
The Fundamentals of Naval Tactics.
in kind) on account of the minor dexterity of the personnel, may
seem comparable to a ship less strongly armed ; then, by applying
the preceding criteria, this ship should be interested in fighting
at long range, which would evidently be absurd. But the error
lies in the comparison made; in fact, logically, the conditions of
the said ship are to be compared with those of a hypothetical
ship, the guns of which increase in number as the distance
diminishes.
(2) Analogously to what has been said under the hypothesis
of a superiority constituted exclusively by medium guns, in order
to utilize to the maximum degree a superiority in heavy and
medium guns, battle in the third and fourth zones would seem to
be advisable. However, the importance of the initial advantage
is to be taken into account, and the expediency of avoiding, as
far as possible, having the superiority compromised by lucky
shots. Consequently, at the ■ beginning, long-range combat is
preferable, passing afterwards to medium range, and finally to
close range, in order to give the coup de grace. The combatant
that gets the worst of it in the artillery battle, if he has not the
possibility of imposing a fight at close quarters, will decide to
launch torpedoes at long range. For the adversary, that might
be the opportune moment for diminishing the distance and launch-
ing torpedoes without too many risks and with greater probability
of success.
27. Differences in the Means of Defense. — On the basis of
what we have noted in section 4 (Chapter I), a good distribution
of 150 millimeters armor constitutes the minimum sufficient and
necessary for the struggle at extreme range and at long range
against ships armed with guns of heavy caliber. Aptitude for
battle at shorter distances requites a thickness greater than the
said limit, at least in the water-line belt. These criteria seem
sufficient for estimating the influence that the relative conditons
of protection of the adversaries may exercise upon the choice of
the distance.
Ships with but little protection, but with great offensive power,
may be employed against the secondary (unarm or ed) forces of
the enemy, and also — if deemed necessary — against the principal
forces, taking care to safeguard them in the manner indicated in
Chapter III ; in which case, however, the choice of the opportune
tactical zone for the whole fleet is made independently of the
presence of such ships.
54
The Fundamentals of Naval Tactics.
Aside from this hypothesis, ships with little or no protection
should avoid battle with strongly protected ships ; but, when
obliged to fight, they should seek to come to close range.
28. Conclusions. — On the basis of the preceding analysis, let
us sum up for each tactical zone the conditions under which it
may opportunely be selected.
Zone I is suitable for the search after the initial advantage, for
the combatant that, by reason of the strategic situation, can least
afford to risk his forces. It requires great organic preparation
of the personnel and of the material. It is generally not capable
of producing decisive effects, but is capable of accentuating
differences.
To the one who desires to push the fight to its decisive phase,
this zone would not be suitable when he cannot count upon a
sufficient number of hours of daylight.
Battle in this zone is not possible except under the best weather
conditions.
Zone II. — The combatant in the strategic situation above men-
tioned will pass to this zone after obtaining an initial advantage
in the first zone, unless, having a greater number of heavy guns,
he elects to develop the entire action in the latter. It will be the
one in which, generally, the initial advantage will be sought by
the combatant who desires the battle to take place in its various
degrees of intensity. It is capable of decisive effects. Generally,
both the adversaries will agree in desiring a prolonged phase in
this zone.
Zone III is suitable for the one who obtains the advantage in
the preceding zone, or who has an important superiority in
medium-caliber guns, or heavy-caliber guns in bad condition.
Zone IV is generally suitable for giving the coup de grace, or
when one has superiority in torpedo armament, or when one has
ships more heavily armored than those of the enemy.
Zone V is not suitable for the one who has obtained advantage
in the preceding zones. Whoever may wish to attempt a desper-
ate stroke in order to re-establish his chances in the fight, will
seek to enter this zone.
55
PART II.
MANEUVERING.
CHAPTER I.
Ideas on Naval Kinematics.
29. Preliminaries. — The motive that induces us to cite a few
fundamental ideas on naval kinematics must not be sought for in
a desire for mathematical divagations, nor for the study of battle
maneuvers on the basis of aprioristic hypotheses concerning the
movements of the enemy. The object that we propose for our-
selves is that of determining criteria of the maximum simplicity,
holding it to be an axiom that, in ofifensive contact, it is absurd
to place confidence in tables, diagrams, or instruments for geo-
metrical constructions. Furthermore, it is well to give notice
that, while not excluding such means in contact out of range, and
during exercises (and in the latter only until a sufficient habit in
maneuvering is acquired), the only one of them that we deem
indispensable for the conning of a ship under the fire of the
enemy, is that composed of a horizontal disc upon which are
marked the sectors of offense of the weapons, and in the center
of which is a revolving alidade furnished with a sight vane.
But precisely in order to be free from all shackles, clearness of
ideas is necessary concerning the solution of the principal prob-
lems of kinematics, and toward this we shall tend, limiting our-
selves to the purely indispensable.
To fix the idea, let us refer to the case of two ships opposed to
each other, observing that, on the basis of the deductions of
Chapters I and IV of Part I, we cannot confine ourselves to
considering the rectilinear tracks.
Indeed, in long-range battle, if we suppose that our ship is
in the proper tactical zone, that the enemy bears approximately
in a direction of maximum utilization, and that we maintain a
constant course, after a short time — except in very particular
cases — the inclination to the plane of fire could not be held to
57
The Fundamentals of Naval Tactics.
answer to the tactical necessities ; and hence it will be necessary
to follow a new course.
In general, rather than change the course at intervals, and so
disturb the fire control, there naturally comes the idea of satisfy-
ing the tactical necessities continuously rather than intermittently,
by keeping the polar bearing of the enemy constant for a certain
time, which can easily be done by means of the alidade of the
instrument just mentioned. In this way, the track passed over is
generally curvilinear ; and its curvature is naturally a function of
the enemy's track. As — steering thus by means of the sight vane
— the ship continually changes her course, the doubt may arise
that the disturbance of the firing may be continuous ; we establish,
then, the idea of taking also into consideration these curvilinear
tracks, unless upon examination their radii of curvature prove to
be very great. It is clear that if such conditions are realized, they
present a real advantage by substituting continuous, but very
slow, changes of course for those of notable amplitude between
the successive courses of a broken right line.
Setting aside the effect upon the firing, it is intuitively seen
that steering on a constant bearing may be advisable under some
circumstances, because it permits the maximum simplicity of
maneuvering that can conveniently be adapted in a continuous
manner to the maneuvering of the enemy.
When the advisability of the continuous adaptation just now
mentioned does not exist, and the problem is that of taking, with
the greatest rapidity, a determined position with respect to a ship
or a fleet of ships, the necessity of rectilinear tracks is evident.
In fact, they permit of attaining the desired object in the mini-
mum time, unless a curvilinear track may be convenient in order
to diminish the uncertainties of the maneuver, and may permit
of reaching the desired position in a space of time only slightly
greater than the minimum.
In general, then, we may establish the necessity of rectilinear
tracks :
(a) In contact out of range.
(b) In the maneuver of approach of a light, swift vessel.
(c) In the movements of friendly ships (evolutionary prob-
lems) .
Bearing in mind what has previously been said, for the study
of the movements of two ships — which fonns the object of this
S8
The Fundamentals of Naval Tactics.
chapter — we are to consider rectilinear movements and those on
a constant bearing.
30. Indicator of Movement (Fig. 12). — Let us consider the
simultaneous positions of two ships, A and B, of which Va and
j/g are the respective speeds, and AA.^ and BB^, the courses. If
^1 and Si are the simultaneous positions of said ships after an
infinitesimal time dt, let us take A-^A-^' parallel and equal to BB-,,
but in a contrary direction. The distance A^'B is equal to that of
Aj^Bi ; moreover, the joining lines A^B■^ and A^'B form the same
angles with the courses of B and A. The geometrical locus of
the points A^^' (of which A is the origin) is the trajectory or indi-
cator of the relative movement of A with respect to B, called.
T^S
Fig. 12.
briefly, the indicator of movement ; or, in other words, it is the
track that the ship A, at a speed which is the resultant of Fa and
V (the relative speed), passes over with respect to the ship B.
which is supposed to be stationary.,
31. Generalities Concerning Rectilinear Movements (Fig. 12).
— If the tracks of A and B are rectilinear and the speeds Vt. and
Fb are constant, the indicator of movement will be rectilinear.
In fact, from what has been said, the points of A.^ are aligned
with A, the resultant of the speeds being also constant.
Consequently, if A must determine the proper course for bring-
ing itself into a given position with respect to B, it is well to
observe that the course that corresponds to the hypothesis of an
immovable B is the indicator of movement; the problem is then
reduced to that of passing from the indicator of movement to the
course of A.
59
The Fundamentals of' Naval Tactics.
If we imagine a circumference described with its center at A
and with any radius AA-^ which we take as a unit of measure, the
course sought is obtained by joining A with the point A.^ of said
circumference, the parallel from which point to the course of B
cuts the indicator in a point, ^i', such that we may have *
AA, Vj. '
If a and /8 are simultaneous polar bearings of A and B respect-
ively (counted from the bow), indicating the relative speed by
Vr, from the triangle AA^A^ we have
wherein it is necessary to use for /? the positive or the negative
sign, according as the two ships move toward the same side or
toward opposite sides of the line joining them. The rriinimum
value of Vr is Fa — Pb , which corresponds to parallel courses in
the same direction.
If J is the segment of the indicator included between the points
corresponding to the initial position and the final position, the
time t necessary for completing the movement is
Furthermore, indicating the angles formed by the courses of
A and B with the indicator of movement by yt, and ye respect-
ively, from the aforesaid triangle AA^A^' we obtain
K .
smyj,= ^j^smyB' (2)
Since it must be that sin Ja^i, there results from this relation:
1st, that any change of position of a ship, A, with respect to
another, B, which is steering a fixed course, is possible when
Fa > Fb ; 2d, that if A has not superior speed, there are possible
only those changes of position for which sin y^ < ^* ; 3d, for a
, Fb
value of 3/B, two supplementary values of y^ satisfy the above-
* Marking off from A a segment ~ , parallel to the course of B and in
the same direction as Vb , and drawing from its extremity the parallel to
the indicator of movement, the point Ai is determined by the intersection of
this parallel with the circle of center A and radius i. (Author's note.)
60
The Fundamentals of Naval Tactics.
mentioned relation. It is easily seen, concerning the aforesaid
geometrical construction, that when Vj,= Vb, a relative speed, 0,
corresponds to one of the said values of j/a; if Va< Vb, the rela-
tive speeds corresponding to the two values of yj, are made in the
same direction ; and this must be taken into account in order to
select the proper value of ^a, since both the values of yj, bring-
one to the desired position, but in different times; finally, if
Vi> V , the two values of the relative speed have contrary signs.
32. Chase Problems. — The simplest application of the preced-
ing deductions consists in determining the proper course for over-
taking another ship.
In this case, the indicator of movement is the joining line AB ;
therefore, during the movement, the two ships keep each other
on the same polar bearings. The course sought can be determined
with the geometrical construction, already mentioned, which it is
superfluous to recall as it is practically done with an instrument
having two alidades. The immediate determination of the proper
course would require exact knowledge of the course and speed
of the other ship ; this not being presumable, recourse must be
had to successive rectifications.
When there is no instrument available except one with a single
alidade — mentioned in Section 29 — the course to be steered must
be estimated by eye and afterwards corrected until the polar bear-
ing remains constant. In this way the ship A which gives chase
generally follows a brqken rectilinear track ; we shall presently see
how the rectifications just mentioned may be limited.
Conformably to observation 3 of the preceding section, the condi-
tion that the course steered should keep the polar bearing constant is
necessary, but it is not sufficient to bring about a meeting ; in fact,
this may be verified for two courses of A which form supplemen-
tary angles with AB. When Vi.< Vb the meeting is not possible
if B holds A on a polar bearing, from the bow, greater than that
of which the sine is'— =-^ . Both the above-mentioned courses may
Vb
lead to a meeting, but naturally the one which makes the greater
angle with the said joining line cannot secure the object in the
shorter time; and the existence of such a solution is worth re-
membering in practice in order to avoid errors. In the case of
J/a = Vb, the course that makes the greater angle with the joining
61
The Fundamentals of Naval Tactics.
line and keeps the polar bearing constant, is parallel to the course
of B; or, geometrically, it would lead to a meeting in an infinite
time. Finally, when Fl > T , the course of A, which makes the
greater angle, diverges from the course of B, and the ships may
be considered as departing simultaneously from the point of
intersection of the courses.
This being said, we observe that if A steers on a constant polar
bearing equal or nearly equal to the one necessary for reaching a
meeting in the shortest time, the indicator of movement is recti-
linear, or it is very nearly a straight line ; and hence A arrives
at the meeting in the minimum time, or in a time slightly greater.
It is unnecessary, then, to establish the precise condition that the
Fig. 13.
track of A be rectilinear ; and this suggests the practical rule of
not troubling oneself too much about the aforesaid rectifications
of the course, but determining an approximate course, and then
steering so as to keep constant the polar bearing thus obtained.
II. The problem just discussed is a particular case of the fol-
lowing : To determine the course that a ship, A, must steer, with
a speed Fa, in order to arrive, in the minimum time, from a dis-
tance R to a distance r from a ship, B, which steers a rectilinear
course at a speed Vs] in case this is impossible, to determine the
direction in which A must move in order to reach the minimum
distance from B.
In order to solve this problem, let us first of all demonstrate
that if A' and B' are the positions of A and B when A has reached
the distance r from B in the minimum time, the three points A,
62
The Fundamentals of Naval Tactics.
A' and B' are in a straight line. This may easily be demonstrated
by an absurdity.
Let us suppose 7?>r. Let us also suppose that A' is not
upon the joining line AB' (Fig. 13) and that A^^ is the point of
intersection of AB' with the circumference whose center is at A
and whose radius is AA'.
Let A" be the point of intersection of AB' with the circumfer-
ence whose center is at B' and whose radius is B'A' = r. It is
clear that A A" is less than AA^ ; if, then, the ship A had followed
the course AB' it would have arrived at a distance from B less
than r, in a time equal to that occupied in passing over AA'. Into
such absurdity one always falls, except in the case in which A' is
on the joining line AB' ; the alignment mentioned is therefore
necessary. The proposition enunciated is analogously demon-
strated if i?R, the solution of the problem enunciated is obtained
in a way analogous to that required for r<,R, observing that the
course on which A reaches the distance r in the shortest time,
65
The Fundamentals of Naval Tactics.
cuts the line of the course of B ahead of that ship, and at a dis-
tance r— ; hence, unless A is exactly astern of B, the most
opportune course for increasing the distance up to a certain limit
as rapidly as possible, must be a diverging one.
33. Evolutionary Problems. — I. Let us suppose that B (Fig.
16) follows the course BX at a constant speed. If A finds itself,
nx
\/
Fig. 16.
with respect to that ship, at a distance »-i and on the polar bear-
ing /?!, and desires to pass in the minimum time to the distance rj
and to the polar bearing /Jj — that is to say, to a position P with
respect to B, which is supposed to be stationary — the line AP is
the indicator of movement ; and hence, with reference to it — as
has been set forth in Section 31 — setting aside the displacements
due to changes of course, we may determine the course AA' that
A must follow, and the necessary time.
66
The Fundamentals of Naval Tactics.
The problem thus set forth is the one that presents itself when
we aim at transporting ourselves from contact out of range, not
only to a certain distance from the enemy, but also to a deter-
mined relative position.*
Moreover, what has just been said includes generically the
cases realized in evolutions that are not performed in succession.
If ^1 = 1^2, AB is the indicator of movement, and the evolution
reduces itself to a change of distance; if r^ = r2, the evolution
consists of a change of bearing; the indicator of movement is
then normal to the bisector of the angle PBA ; that is to say,
PAB = QO°-—,
2
(0 being equal to ^^ — p^.
II. Let us now consider the changes of bearing.
The perpendicular segment dropped from B upon AP — that is
to say, AB cos — — indicates the minimum distance at which the
2
ships will pass during the evolution ; it is generally held that the
distance ought not to fall below 7/10 of the normal distance,
which establishes for w the limit of 90°.
It is easy to find the formula which permits of obtaining the
angle 8 through which A must change course, supposing, natur-
ally, that in the position A, the said ship has a course parallel to
that of B. From the figure we get
h=i?,o° -p^-PAB-y^,
in which
PAB = go°- —
2 '
and j'A is given by equation (2) of, Section 31 ; that is,
Tb .
j/i^d-ii; sill 1
Then, since
j/A = arcsm(^— sm j/B
sinj/B=sin(i8o°-j8i-P.^5)=cos(3i - -|-) ,
we obtain
8 = 90°-!- — ySj — arcsin
|i-cos(..-^)j. (3)
* If the movement of B, instead of being on a single course, can be pre-
dicted to follow a broken rectilinear track, the method to be followed is
evidently analogous to that indicated in the preceding section. (Author's
note.)
67
The Fundamentals of Naval Tactics.
The change of course must be made toward B, or in the oppo-
site direction, according as 8 is positive or negative.
In order to be able to pick out the value of 8 from a table, the
latter might be one with two entries (that is, /?i— -^ and the ratio
of the speeds).
In order to eliminate the use of tables, recourse should be had
to diagrams,* to an instrument with an alidade, or to the method
by parallel courses, making the ships change course through the
angle 90°+ — — /3^ in a way that may result in the direction APj
B afterwards executing the reduction of speed. With this latter
method the relative speed is Vk—Vb', and hence the time neces-
sary for the evolution remains at that corresponding to the
method above indicated {AP being always the same) in the ratio
— - — *" , by virtue of equation (i) of Section 31. Hence it is
evident that the evolution by the method of parallel courses can
never occupy less time than that which is required by the other
method, which we will call the method by oblique courses.
A general rule — which we shall suppose to be implicitly fol-
lowed in the evolutions when nothing is specified to the contrary —
is that the ship B at the beginning of the evolution (or. before
reducing the speed) makes the two changes of course (initial and
final) that A makes at A and at A' ; with this rule, mentioned by
Admiral de Gueydon,f the displacements due to changes of course
are rendered the same for A and for B.
III. Definitions. — If two ships have the same course and speed,
and the one further advanced in the direction of the course is
bearing from the other at an angle a from the bow, we say that
it is on the line of polar bearing a.
By wheeling a line of polar bearing we mean the evolution by
oblique courses which permits of rotating the line joining the two
ships, at the end of which rotation the former polar bearing of the
formation is re-established.
* Pesci : Sui metodi per cambiare il rilevamento fra le navi di una forma-
zione semplice, Rivista Marittiiua, March, 1897.
t Tactique Navale. Recherche des principes primordiaux et fondamen-
taux de toute tactique navale (1868).
68
The Fundamentals of Naval Tactics.
Fig. 17 shows a line of bearing that executes a wheel through
an amplitude c and (j>t the respective values of for the
wheel on the rear ship and that on the leading one.
In the first case the value of 8 is determined, bearing in mind
that the pivot ship changes course through the angle w, and that
hence, in equation (3), it is necessary to put y3i = w; in this way
we get
&=90° —arc sin
and hence
Vb <•'
^cos-
<^c = 90°+ ^-arcsinf^cos ^). (4)
For the wheel with the leading vessel as a pivot it is necessary
to substitute in equation (3)
/3i = i8o + «),
from which we obtain
-<^t = 90°-— -arcsin (-^ cos-
2 Wi. 2
Taking absolute values for <^c and t we get
<^c — 4>t = <^, (S)
which, together with equation (4), permits of the construction of
a table which will give the angle of the change of course for a
given speed ratio.
From equation (5) it is clear that, in order to apply the rule of
De Gueydon, the pivot ship, in wheeling on the rear vessel, iTiust
change course through 4,0 in the direction of the wheel, and after-
wards execute a change through c^, in the opposite direction; in
the case of pivoting on the leading ship, the pivot ship must
change course through <^t in the direction opposite that of the
wheel, and afterwards through „ in the direction of the wheel.
70
The Fundamentals of Naval Tactics.
IV. By equation (i) of Section 31, the time necessary for
executing a change of bearing (or a wheel) of an ampHtude m, is
. r, 2AB Sin -—-
t^ AP_ = ^ (6)
from which it is seen that the duration of the evolution is propor-
tional to the length AB of the line or column.*
Let us now compare the rapidity of wheeling a column of vessels
by the two methods indicated.
Let B be the pivot ship (Fig. t8). According as the ship A is
at A2 or at A^ — that is to say, ahead or astern of the pivot — in
order to wheel the line through w, we find ourselves in the case
of pivoting on the rear or on the head.
A2' and A^' being the corresponding positions of A at the end
A R
of the evolution, let us determine what must be the ratio — i— ,
A^B
to the end that we may have A^A^^A^A-l. By virtue of the
proportionality before mentioned, this ratio indicates the relative
rapidity of the two methods, which we will indicate by -^ ,
^2 and fi being the times respectively employed in the case of
pivoting on the rear and on the head.
Considering the triangles A-fiA-^, A^BA^, by equation (5),
we have
A^A'B^<^t;
X-yA^'B — c;
and hence
sin ^t sin oj
sin 00 sin m
A^tj A 2A 2
A^B ~ A^Ay'
* The ratio between the times necessary for the evolution by the method
of parallel courses and by that of changing direction in succession is
2 sm —
^ Fa,
Fx-Vn
or the first of these methods is more rapid if
Vb
-< -
With this formula, for-^ = -|, (^Sag"; for ^- = A, "t
Calculating c and t by means of equations (4) and (5), we
deduce from this formula the values of the ratio
A,B
A.,B
, which
^1
Fig. 18.
values, set down here below opposite ta, are determined under the
hypothesis that
Fa
IS"
30°
45°
60°
A
ti
1.16
1-35
I.S7
1.78
75 2.00
90° 2.24
72
The Fundamentals of Naval Tactics.
It results from this table that the greater rapidity is obtained
by pivoting on the head; by the other method, for the supposed
speed ratio, about double the time is employed if w is between
60° and 90°, and one and a half times more if w is between 30"
and 45°.*
Let us now consider the time required for changing the direction
of the line through the angle da';
and hence, by equation (9),
tr ^' I
P Vb) start at a distance ro, and the swifter
vessel follows a logarithmic spiral with its pole in the initial position of the
slower ship, and inclined to the radii vectors in such a way as to keep
the pole bearing at an angle whose cosine is — rr- , while the slower ship
Ka
steers on a radius vector, the distance between the two ships varies until
it returns to n, when the swifter ship passes ahead of the other. Fournier
based himself on the hypothesis that the slower party, with the intention of
diminishing the distance, might follow a rectilinear course, or keep his bow
constantly on the enemy. In consequence of this, and of the fact that the
faster ship, which passes over arcs of a logarithmic spiral conformably to
the theorem aforesaid, has not the enemy constantly bearing in a sector
of maximum offense, the maneuver with limited distance in the way pro-
posed by Fournier is not acceptable. (See our study entitled "La velocita
nella tattica navale," in Rivista Marittima of January, igoo). Nevertheless,
Fournier's book efficaciously contributed to the progress of Tactics by
initiating the study of long-range battle. Following Fournier came Com-
mander (now Admiral) Baggio-Ducarne, who, studying the application of
Fournier's criteria (Rivista Marittima, April, 1897), adjudged to Admiral
Saint-Bon the merit of having, in 1885, perceived and demonstrated, in a
tactical exercise, the advantage that a ship, swifter and more powerful
than another, may draw from long-range battle. Comandante Ronca first
pointed out the convenience of keeping the distance constant (Rivista
Marittima, June, 1897). (Author's note.)
86
The Fundamentals of Naval Tactics.
which we will call the equation of constant distance. It results
from this that, theoretically, a ship, A;can maneuver at a constant
distance from another ship, B, in two ways: ist, at a constant
speed, pre-establishing Va, and determining the polar bearing u.
on which he must keep the enemy by means of the equation
cos a = — 5_ cos 6,
so that a is constant if B keeps $ and Vb constant ; 2d, on a con-
stant bearing, pre-establishing the polar bearing in which the
enemy must be kept, and assuming the speed
r/ Vb cos 6
cos o.
SO that Va is constant if B keeps 6 and Fb constant.
Each of these methods presents grave inconveniences. Brief
considerations suffice to show that, in general, with one of the
above-mentioned methods, if the maneuvering, of the enemy is not
rational, our maneuvering also cannot be the most opportune.
With the method at a constant speed, if B keeps A on a variable
bearing, 6 (as may happen, for example, when B keeps the course
constant), a must also be variable. If 6=90°, a must also be 90" ;
corresponding to 6 = and 6=180°, we have, respectively,
cos a= ° and cosa= -~ . Consequently, if the enemy
Ka ^a
should constantly present his beam, in applying this method our
ship should act in the same manner, which is illogical. If the
enemy has our ship bearing in line with the keel or in a sector of
minimum offense, with the values that the speed ratio may as-
sume in practice, our polar bearing also would generally be out-
side of a sector of maximum offense. Moreover, if Va> Vb ,
cos ab = i5 knots, the time necessary to
rotate the joining line through go° is only 23 minutes. However,
for the case in which, by presenting to the fire the side of the
same name as that of the enemy, we may expose ourselves to
having a rotation of the joining line in a direction contrary to
that desired, let us see how the rotation can be obtained by pre-
senting the side of the opposite name.
It is clear that, in order to have the maximum component of
the speed normal to the joining line, it is necessary to maintain
the maximum speed instead of reducing it according to the cri-
tance, the line O' 1, Cn should at all times be parallel to the joining line AB.
But, considering the positions A' and B' of the two ships after the time dt,
C A Cu should also be parallel to A'B', and hence we should fall into an
absurdity. In order to avoid this we must admit the coincidence above
mentioned. (Author's note.)
92
The Fundamentals of Naval Tactics.
terion given in the preceding section ; and it is expedient to have
the enemy bearing as near as possible to the beam, or, in one of
the pre-established limit directions OM', OM", of Fig. 22. If
with the sight vane in one of these directions the distance changes,
we continue to steer in this way up to the limit established for
the distance, and then steer in the symmetrical direction with
respect to the beam. So doing, by virtue of the aforementioned
formula (10), the ship A sees the line joining it with the enemy
incline itself in the direction in which the ship is moving, if there
is realized the condition
Fa sin a> Fb sin 6.
When A has sufficient speed to permit the existence of this
inequality, it is best to recognize that the above-mentioned man-
euver is suitable only when a rotation of moderate amplitude is
required. In fact, if F=i8 knots, supposing the bearing on
which A steers to be such as to keep the distance constant, r, 6,
and V^ being the same as in the example previously considered,
two hours are required in order to rotate the joining line through
90° ; but it may be observed that, to make the joining line rotate
through 270°, by presenting to fire the side of the same name as
that of the enemy, the necessary time would be ?Z_X23 minutes,
or a little more than half the time above mentioned. Hence, for
rotations of great amplitude, avoiding the inconveniences of keep-
ing the enemy bearing too near the beam and gaining in celerity,
it would be advisable to produce the complement in 360° of the
required rotation.
We may then establish :
1st. In order to maintain an advantageous position with respect
to the sun, to the coast, or to the strategic objectives, we must
present to fire the side of a name opposite that of the enemy,
applying the general type of maneuvering indicated in the pre-
ceding section.
2d. We must present to fire the side of the same name as that
of the enemy, applying the general type of maneuvering, when
in that way the rotation of the joining line takes place in the
desired direction, or when the amplitude of the desired rotation
is very great.
3d. If in presenting the side of the same name as that of the
enemy the rotation takes place in the direction contrary to that
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desired, if, furthermore, the desired rotation is of small ampli-
tude and we have a speed superior to that of the enemy, it is well
to present the side of the opposite name, maneuvering by the
rules just pointed out. When, however, we have not sufficient
speed for obtaining the object established, it is necessary to
maneuver as has been said in the preceding case.
It results from the foregoing that it may be easier to maintain
an advantageous position than to acquire it. In general we can
have but little faith in being able to apply the second of the pre-
ceding deductions, for it is presumable that the enemy, when he
sees our ship present the side of the same name as his own, may
change the maneuver by exposing his other side if he deems it to
his interest to avoid a rapid rotation of the joining line. Still,
the contrary might happen when, for example, the enemy has
commenced firing before we have done so, and does not wish to
change the side, in order to avoid the disadvantage to the fire
control that would be produced.
Evidently it would be a fine game if the enemy were obliged to
present a determined side, as would be realized if his offensive
field were unsymmetrical with respect to the longitudinal axis.
42. Change of Distance. — I. It is clear that in order to obtain
a change of distance without sacrificing offensive power, a ship
A must develop the maximum speed and keep the enemy bearing
at the forward limit of a sector of maximum offense if he desires
to diminish the distance, or at the after limit if he desires to
increase it. The enemy B, in order to maneuver by the same
standard, hindering the change, must keep A bearing respectively
at the after limit, or at the forward limit of a sector of maximum
offense.
By the fundamental relation, the ship A may impose a change
of the distance when
Va cos a> Fb cos 6 ;
u. and 6 corresponding in this case to the limits of the sectors of
maximum offense.
II. Let us now suppose that the two adversaries are at the limit
of offensive contact. The object of the ship A is to engage in a
decisive combat with the ship B, which, not being able to prevent
the approach of A, proposes to limit the action to the maximum
distances. It is easy to see that if the ship B is powerfully armed
on the line of the keel (has powerful head and stern fire), it may
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be interested in keeping the stern always toward the enemy. In
fact, if A, steering by sight vane, keeps B at the forward hmit
of a sector of maximum offense, caUing this bearing a — counted,
as usual, from the bow — by the fundamental relation (wherein
we must, in this case, put d = o) it results that the necessary con-
dition to the end that the distance may not increase, is
Fa > I
Fb " COS a ■
Consequently, the minimum speed necessary for A, in order to
develop against the enemy the maximum power without falling
out of range, is that corresponding to the greatest amplitude of
the sectors of maximum offense; or it is determined by the
relation
Fa
Fb cos 30'
Putting A = Fa — J>B , we have
= 1.15.
Fa _ A
Fb ~^+ Fb '
or
A = 0.I5 Fb.
Hence it results that the superiority in speed required by A is
so much the greater, the greater is Fb; or, while a greater speed
per hour of 1.5 knots is necessary for the object mentioned
against a ship of 10 knots speed, when F=20 knots, there is re-
quired an advantage of 3 knots.
This said, the following observations should be made :
1st. The aforesaid advantage in speed simply permits the ship
A to keep B under the fire of his guns, but does not admit of his
diminishing the distance.
2d. As has been pointed out in Part I, Chapter I, some ships
can develop a strong intensity of fire in the direction of the keel —
much greater than that of which they are capable in the sectors
of minimum offense; moreover, it is well to remember (Section
3) that, at the maximum fighting distances, a ship presenting
itself end on to the enemy's fire diminishes in that way the enemy's
percentage of effective hits.
3d. It is true that, being removed by a small angle from the
direction of the keel, one enters a sector of minimum offense;
but this may also happen for the limit direction of the sector of
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maximum offense on which A is steering; in other words, if A
desires to provide against the inexactness of steering by sight
vane, rather than at 30° from the bow, it ought to keep the enemy
at about 35° ; but then, for F=20 knots, there would be required
an advantage in speed of 4.4 knots, rather than of 3 knots. It
seems, then, that we may affirm that, even supposing the sectors
of maximum offense to have the maximum ampHtude, without a
great advantage in speed, not presumable in practice, the situation
is not very decidedly favorable for A. On the other hand it
appears to be clear that B may not he interested, in this case, in
conforming to the general rule, which is that of keeping the
enemy bearing in a sector of maximum offense.
If the ship A, then, has not a speed which greatly exceeds that
of B, his desire to succeed in the intention to diminish the dis-
tance constrains him to keep his bow toward the enemy; which
obliges him to endure, for a very considerable time, a disadvan-
tageous situation, when the strength of his fire in line with the
keel is inferior to that of the enemy. In fact, it is sufficient to
note that, in order to diminish the distance by at least 2000 meters —
which it is important for A to do in order to engage in a quickly
efficacious action — the necessary time is that which would be
required for passing over the said space at a speed Va.— Vb ; or,
it is more than 20 minutes if the difference in speed is about 3
knots.
When, however, the ship A, besides being the swifter, has also
a more powerful fire in line with the keel, it is clear that B will
be obliged to bring it to bear in a sector of maximum offense;
we then come back to the case already discussed at the beginning
of this section.
In the general case of two ships opposed to each other on the
open sea, we may then conclude :
1st. That, for declining a decisive tactical action, powerful
stern fire may constitute a compensation for inferior speed.
2d. That a speed superior by two or three knots, even if asso-
ciated with the maximum amplitude of the sectors of maximum
offense, cannot be held to be sufficient for imposing the tactical
action; powerful fire ahead is more important for securing that
object.
43. Capacity for Tactical Initiative.' — A ship has complete
liberty of tactical initiative with respect to another if it can
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The Fundamentals of Naval Tactics.
impose or decline offensive contact; and if, in case it engages, it
can give to the action the form that is deemed preferable, or can
control its development.
After what we have said, it is easy to estimate in what degree
such liberty is possessed ; that is, to determine the elements of the
capacity for tactical initiative with reference to the usual hy-
pothesis of ships opposing each other on the open sea.
I. In the general case in which the distance at which the ships
sight each other is beyond the limit of offensive contact, equality
of speed is sufficient for avoiding said contact, while, to impose
it, a superior speed is necessary.
II. For the slower ship, the capacity for limiting the offensive
contact to the maximum distance is inversely as the capacity of
the faster ship to impose a decisive combat; in practice, they
depend essentially upon the relative potentiality of the two adver-
saries in fire in line with the keel.
III. As between two ships that keep each other bearing in sec-
tors of maximum offense, the capacity for controlling the dis-
tance depends .upon the relative conditions of maximum speed
and of amplitude of the sectors of maximum offense ; these two
factors should be considered together for each combatant; or, a
compromise between them is possible. Indeed, as is seen from
the fundamental relation, the aptitude of a ship to control the
distance depends upon the product of its speed by the cosine of
the angle formed by the longitudinal axis with a limit direction
of the sector of maximum offense. If the forward limit direction
of this sector forms with the direction of the bow a certain angle,
a — fx, this places the ship in the condition in which it would be
found if the limit direction formed the angle «,, but the maximum
speed V had an increment, kV, k being a coefficient that renders
Vcos(a-ii,) = iV+kV)cosa;
hence we have
^_ cos(a-^) _^
cos a
If we were considering the after limit direction of the sector
of maximum offense it would be necessary to put i8o°— a in
place of a, and i8o°—a + fi instead of a — ju; hence the formula
found for A is a general one.
In the three hypotheses (Section 2) of sectors of maximum
offense extended to 30°, 45", and 60° from the beam, the values
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The Fundamentals of Naval Tactics.
of k for ;u.= S" are respectively 0.14, 0.08, 0.04. For /i=io° the
values of k just given are doubled; that is, k may be held to be
proportional to fj,. For the ordinary case in which the two ships
have sectors of maximum offense with amplitude near to 45"
forward of and abaft the beam, it is then to be remembered that
if a ship has, with respect to another, the limits of the sectors of
maximum offense nearer to the longitudinal axis, every 5° of dif-
ference of this kind, or every 10° of advantage in the total ampli-
tude of the sectors, is equivalent, in the particular regard now
under discussion, to an increase of speed of 8/10 of a knot for
every 10 knots.
IV. Generally the maneuvering of a ship in the duel is de-
veloped by keeping the adversary in one of the four fractions of
the sectors of maximum offense ; as, SOM", S'OM' of Fig. 22,
included between the limit directions of said sectors and the
directions nearest the beam to which corresponds a sufficient
defensive capacity ; the wider these partial sectors are, the greater
is the liberty of maneuvering. From this comes the superiority
that is derived from greater thicknesses of armor than those of
the enemy, or from guns with greater penetrating power.
V. To the end that a ship may be able to impose the rotation
of the line joining it with the enemy, it must be able to obtain,
with respect to the enemy, a greater component of its speed nor-
mally to the said joining line. This depends upon the relative
speed conditions and upon the angles that, for each ship, the
directions OM", OM' of Fig. 22 forrn with the beam. In this par-
ticular respect an advantage in speed is hence equivalent to a
greater thickness of armor or to a greater penetrating power of
the guns.
From the preceding observations it results that the importance
of the various elements of the capacity for tactical initiative
cannot be considered in a one-sided manner.
It is incontrovertible, then, that the said capacity increases with
the amplitude of the sectors of maximum offense ; but with this
amplitude (Section 3), the ratio between the potentiality in line
with the keel and that of the said sectors diminishes ; nor, on the
other hand, can an increase of the said amplitude render an ad-
vantage in speed less desirable. This deduction is to be borne in
mind when considering the types of ships.
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44. Maneuvering at Close Range. — Let us examine the manner
in which maneuvering at close range may be developed; that is
to say, within the limits of the fourth tactical zone distinguished
in Section 24, when the employment of the torpedo is possible,
and hence, from what we demonstrated in Section 9, it is prefer-
able to have the enemy bearing abaft the beam.
It must be borne in mind (Section 3) that the probability of
being hit by the guns at close range, while it remains constant if
the direction in which the enemy bears is not removed more than
45" from the beam, rapidly increases beyond that limit ; therefore
it is not advisable to have the enemy bear more than 45° from
the beam, or, it is not advisable to utilize a greater amplitude of
the sectors of maximum offense.
In maneuvering at close range, then, we should generally have
the enemy bearing in a direction of maximum utilization abaft
the beam, and should present to fire the side of a name opposite that
of the enemy; because in that way it is possible to steer by sight
vane (Section 37), which permits of satisfying the tactical neces-
sities in a continuous manner.
If the enemy has our ship bearing forward of the beam, it is
well to develop the maximum speed or a speed somewhat inferior
— as has been said for maneuvering at long range — with the
intention of keeping the enemy at the desired distance. For
some moments we may change the angle of the sight vane when
this may be necessary in order to launch the torpedoes ; we must
not, however, forget the risks we run in presenting the beam at
close range; and hence it is necessary to establish it as a rule,
not to execute, within the limits to which we are referring, any
passage from a bearing abaft the beam to one forward of the
beam, or vice versa. In consequence of this, except in the case
to which we shall now allude, the launching tubes of the forward
sectors should be utilized by launching for an angled run.
It is clear that if the enemy maneuvers analogously, keeping
our ship bearing abaft the beam, neither of the combatants is
within the radius of action of the torpedo ; the duel then remains
an artillery battle exclusively.
Let us consider the situation of two adversaries that, at close
range, have each other bearing forward of the beam.
The distance diminishes ; the ship that, at a certain moment, in
order to avoid a further diminution of the distance, brings the
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The Fundamentals of Naval Tactics.
enemy to bear abaft the beam, while the enemy continues to keep
it forward of the beam, presents the beam during the change, and
hence makes — as has been said before — a perilous maneuver.
If neither of the adversaries makes such a maneuver, and if
they present to fire sides of opposite names, they come to close
quarters.
When the sides exposed to fire are of the same name, if one
of the adversaries desires to fight at close quarters, the other
cannot avoid it ; let us suppose that this is not desired by either
of the combatants. They keep the course constant ; and, if the
courses are parallel, the polar bearings are the same at any
moment. Thus, passing on opposite courses, inasmuch as it leads
the two adversaries to present the beam sirmdtaneously, may
seem an opportune form of maneuvering for two combatants,
both desirous of using the torpedo. However, it is to be noted
that only in appearance are the combatants in identical conditions ;
the more strongly armored ship acquires the advantage, owing to
the fact that the adversary abandons maneuvering on the bear-
ing which would permit him to compensate for, or at least dimin-
ish, the greater vulnerability of his armor.
Under the hypothesis that the enemy has our ship bearing for-
ward of the beam, we may then conclude :
1st. It is not necessary to have the enemy bearing forward of
the beam at close range, unless we intend to provoke a battle at
close quarters, or unless we have decided to undergo it.
2d. Not desiring battle at close quarters, the maneuver of hav-
ing the enemy forward of the beam may be rational when our
ship has side armor of greater thickness.
45. Limit of Battle at Close Quarters. — Below a certain dis-
tance from the enemy, a ship may be assured that, if a collision
takes place, it may run into the other, instead of being itself run
into.
Theoretically, when we have the greater speed, we run no risk
in having abaft the beam an enemy who has us forward of the
beam; but it is necessary to take unforeseen elements into ac-
count, and hence the necessity of not having the enemy abaft the
beam below a certain distance, determined under the hypothesis
of equal speeds and equal evolutionary qualities for the two com-
batants. This distance marks the limit of battle at close quarters.
The Fundamentals of Naval Tactics.
Let us consider two ships, A and B (Fig. 25), that have each
other bearing respectively the one astern and the other ahead,
and that have the same speed, V. Let us hold their evolutionary
curves to be circular. We must seek the maximum distance, AB,
which will permit A to arrive at K' at the same time as B.
Let us admit that the arcs BK and MK' are passed over in the
same time — which is not rigorously true, since one is described
Fig. 25.
at the beginning, and the other at the end of an evolution. KK'
must be passed over in the time that A takes in passing over the
semi-circumference ANM.
Indicating by p the radius of the circle of evolution, since A
loses about one-third of his speed, we have
KK'
V
or
KK'=kr.p.
lOI
The Fundamentals of Naval Tactics.
Since AB:=2C0' = 2V0W' + CK'^ = 2Vy+iKK'^ substitut-
ing for KK' its value, we obtain
AB=pV4+h^^=5p (about).
On the basis of the values that we may attribute to p, and con-
sidering that the value found for AB refers to the extreme case
wherein A has the enemy bearing exactly astern, we may hold the
distance of 2000 meters to be the limit of battle at close quarters.
46. Maneuvering at Close Quarters. — Battle at close quarters
has lost the importance that it had in the past when it was held
to be the principal form of action ; for this reason we shall con-
fine ourselves to brief considerations.
The ramming maneuver against a ship with freedom of move-
ment is extremely hazardous. Indeed, the instant at which a
ship must reach the intersection of its track with that of the
enemy in order to obtain the object of ramming him, differs very
little from that at which the said ship would be itself rammed.
For this reason, and owing to the fact that modern ships have
in the gun and in the torpedo most powerful means of fighting,
it is to be admitted that neither of the adversaries is likely to man-
euver with ramming as the principal objective.
In maneuvering at close quarters we must nevertheless take
into account the possibilities of ramming; that is to say, we must
maneuver so as to avoid being rammed. In other words, it is
necessary to maneuver defensively with respect to ramming.
The offensive maneuver for ramming would require having the
bow directly toward the enemy*; for this reason, when the tactics
of the ram were a subject of study, it was admitted that the two
combatants would have steered initially bow against bow ; but,
afterwards, considering that such a direct clash would have
placed both the adversaries in identically disadvantageous condi-
tions (no matter how different might be their structures) , it was
held by the majority of the authors that the two ships would
have turned aside little by little. As a collision at a small angle
is dangerous for the rammer as well as for the rammed, it was also
admitted that the two ships, in order to avoid it, would both have
turned aside with the same helm, thus changing the collision into
a grazing, or slipping past at short distance; after which they
would have executed offensive turns with intent to ram.
The Fundamentals of Naval Tactics.
For the defensive maneuver with respect to ramming, it is not
necessary — as it is for the offensive maneuver — to tend to keep
the enemy at an angle from the bow less than that at which he
keeps us, but it is sufficient that the two bearings be equal. On
the basis of this consideration, the form that it seems the initial
phase of battle at close quarters between two modern battleships
should assume, is not exactly that which appeared probable in
the tactics of the ram. Within the limit of distance indicated in
the preceding section, the two ships will run to meet each other ;
but, instead of steering bow to bow, they will keep on their guard,
following parallel courses; there will thus be, not a grazing by,
nor a passing at very short distance, but a passing at a distance
of some hundreds of meters, such as to permit m.aking use of the
guns and the torpedoes.
After passing by, and before the enemy gets out of the after
sector of maximum offense, it is evidently logical to turn in order
to keep him in that sector; therefore the two ships will turn at
that time toward each other ; and afterwards, for the same reason,
they will change course again, thus following parallel broken
straight lines, having each other bearing abaft the beam ; and
hence, they will draw away from each other. Given — but not
conceded — that the passing by may not have had the gravest
effects, if one of the ships desires to provoke a repetition of
the preceding phase, it will have to turn toward the enemy in
order to bring him to bear about 45" forward of the beam; the
other ship will be obliged to turn also in the same way.
It is to be noted that while admitting it to be unlikely that one
of the ships will maneuver, after the passing by, in order to ram,
the other — unless his mobile and evolutionary qualities are greatly
inferior — by turning with the helm hard over, will be in time to
present his bow to the adversary. Hence we deem rational the
opinion of to-day favoring the abolition of the ram.
47. Particular Cases. — In practice — as was said at the begin-
ning of this chapter — particular circumstances will determine the
form that the duel will assume.
Ordinarily one of the adversaries will be sensibly weaker than
the other, and will seek to reach a movable or a fixed center of
protection. Hence it is possible that the enemy may or may not
be found between the center of protection and the ship that de-
sires to decline battle.
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The Fundamentals of Naval Tactics.
In the second case the weaker ship will evidently have to run;
and will place itself in safety if it has an advantage in speed, or
if its inferiority in speed is not too great, and if the radius of
action in which the said ship must operate has been conveniently
established, taking into account the speed of the enemy's strong-
est ships.
In case, however, it is indispensable to reckon with the enemy
m order directly to reach the center of protection, the weaker
ship could run away if it had an advantage in speed, and seek to
throw the enemy off its track ; but when it is feared that in this
way the ship may run into preponderating hostile forces, it will
steer directly for the center of protection, thus coming into a fight
at close quarters with the enemy.
This is the case in which encounters between torpedo boats
very often take place, especially during blockading operations,
as has been demonstrated in the Russo-Japanese war. The de-
stroyers and torpedo boats of the defense, having come out dur-
ing the night in search of the enemy's battleships, returning at
daylight toward their base, may encounter on their route similar
units of the enemy ; and as, for the said vessels, running to sea-
ward would signify exposing themselves to certain loss, they will
be obliged to fight. The adversaries will steer for each other
bow to bow, so that the fight will first be developed in line with
the keel, and afterwards, by passing each other on opposite
courses, at very close quarters. After this, the units of the block-
ading party, unless they have sustained injuries that impede their
freedom of maneuvering, will invert the course, following the
enemy to the vicinity of the base.
Between protected cruisers, when the weaker is the slower, and
has not a potentiality of fire in line with the keel that is sufficient
for maneuvering by the rule given in Section 42, or when for any
reason it cannot avoid a decisive action, it will seek to escape from
the bad situation by provoking battle at close range. The stronger
ship will evidently be interested in keeping the enemy at a dis-
tance.
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The Fundamentals of Naval Tactics.
CHAPTER III.
Tactical Evolutions.
48. Tactical Evolutions and Maneuvers. — Let us consider a com-
pact fleet with the units grouped in the manner deemed to be ex-
pedient for tactical action, and at the distance from each other
which is established as the normal.
In contact out of range the objective of the movements may be
that of delaying offensive contact, or of taking a determined posi-
tion with respect to the enemy, arriving at offensive contact with
an advantageous alignment. In general the tracks must be recti-
linear. At intervals of time it may be necessary to execute changes
of course or of alignment ; that is to say, to perform evolutions ;
the fleet may then be ordered with the maximum exactness, and
the control may be completely exercised by means of signals.
In offensive contact we find ourselves under conditions different
from those just indicated ; we ought to have at every moment an
opportune alignment and a suitable inclination of the ships to it ;
therefore, in general (as has already been pointed out in section
17), an immediate and continuous adaptation of the proper maneu-
ver to that of the enemy is desirable. Limited confidence can be
placed in signals, because, aside from other things, they require
for their transmission a time that is not inconsiderable, even when
use is made of repeating vessels not stationed in the line. In order
not to be surprised and disconcerted, it is then necessary to be
prepared to maneuver on the basis of simple directives — each
division imitating the movements of the one immediately under
the orders of the commander-in-chief ; and, analogously, the single
ships of each division regulating themselves by the one among
them that is charged with the conduct of the maneuver.
We must, then, necessarily admit that the evolutions cannot, in
general, satisfy the necessities of offensive contact, reflecting (as
already results from section 33) that they ordinarily require two
changes of course of considerable amplitude, which disturbs the
firing ; moreover, when an evolution is ordered, it is necessary to
The Fundamentals of Naval Tactics.
foresee what will be the tactical situation at its end, or, after a
time that is notably long, when the naval force is' numerous. Such
a length requires the prevision alluded to, and, on the other hand,
renders it very difficult — the enemy being free to maneuver accord-
ing to his desire. It is to be observed that, naturally, this pre-
vision is also necessary when an evolution is ordered in contact
out of range; however, if in the course of the evolution we do
not arrive at offensive contact, we may, at least in part, nullify
the effects of an erroneous prevision, by so regulating ourselves
as to delay the approach. Finally for the duration of the evolu-
tion, the movements of the single units are restricted; and it is
clear that this restriction cannot permit the best employment of
the weapons and satisfy the variability of the tactical situation.
Let us, then, admit the principle that in contact out of range we
perform evolutions, and in offensive contact we maneuver; having,
in the latter case, as little recourse to evolutions as possible.
Definitions. — We shall call tactical evolutions those proper for
the government of a fleet in contact out of range, thus distinguish-
ing them from the multiplex evolutions that can be imagined.
Under the name of tactical maneuvers we shall include those
maneuvers that are required for the control of a fleet in offensive
contact.
In this chapter we shall study tactical evolutions, considering
successively the hypotheses that the fleet may have a simple align-
ment and a double alignment. We shall subsequently refer to the
case of separated groups in contact out of range.
49. Evolutionary Speed — Reserve of Speed. — As is well known,
to the end that a ship may keep in the formation it is necessary
for it to have a reserve of speed; or, the normal speed must be
somewhat inferior to the maximum speed of the slowest unit.
On the other hand, in order to render the evolution as rapid as
possible, it seems to us well to establish that, as a general rule, the
evolutionary speed shall always be equal to the said maximum
speed of the slowest unit. Consequently, when, for instance, we
say that the evolution is performed with the speed ratio of ^, it
is established that the pivot ship reduces its speed, not to one-half
of the normal speed, but to one-half of the evolutionary speed.
The minimum reserve of speed that each ship in the formation
should have at its disposition must be a fraction determined by
the normal speed ; or, it must be of greater value the higher is the
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The Fundamentals of Naval Tactics.
normal speed ; in fact, a ship that is not exactly on the desired line
of bearing, in order to get into position, determines by eye the
small change of course necessary ; but, as equation (3) of Chapter
I shows, the amplitude of the change of course — and hence the
time required to get into the formation — depends upon the ratio
between the normal speed and the evolutionary speed, and not
upon their difference. Let us admit that the minimum reserve of
speed may be defined by the ratio
normal speed g
evolutionary speed "TTT-
50. Evolutions to be Considered for a Simple Alignment. — In
relation to what we established in section 18, let us consider a
naval force composed of two elementary alignments, each of
which does not contain more than six ships. Let the naval force
be upon a single line of bearing.
As we said in section 12, the formation has of itself no impor-
tance. Having admitted this idea to be fundamental for offensive
contact, we ought to take it o fortiori as a guide in the study of
contact out of range. In the latter, given the objects that we may
decide upon, the first element to be determined in relation to them
is the course ; when the alignment is adjudged to be satisfactory,
or when a change of course is urgent, such change is made
simultaneously.
This said, let us suppose that the fleet has the proper course,
which we will call the advantageous course, and that it is desired
to change the alignment. The evolution to be performed consists
in a change of polar bearing, which may be executed by one of the
following methods :
1st. By changing course in succession (contromarcia).
2d. By oblique courses.
3d. By methods based upon the wheeling of the single column.
51. Change of Course in Succession. — In order to satisfy tac-
tical necessities, from among the ways in which this method may
be applied, we should select the one that permits of losing the
least distance in the direction of the advantageous course.
The problem being thus set forth, it results therefrom that the
transitory courses during the evolution should not make with the
advantageous course an angle greater than 90".
Let A-t^ . . . . An (Fig. 26) be a line of polar bearing a. A-^Z
being the initial course — which we will suppose to be the advan-
107
The Fundamentals of Naval Tactics.
tageous course — the transitory course must be included in the
semicircle X^ZX^, X^X^ being normal to A^Z. Desiring, then, to
assume an alignment ¥^¥2, it is to be observed : ist, that it is not
well to execute the evolution in inverse order; that is to say, by
changing course simultaneously in the direction A^Aii, which is
without the said semicircle ; 2d, that, for the same reason, in the
evolution in direct order, that is, changing course simultaneously
in the direction AnA^, it is not well, after such change, to execute
the change in succession in the direction A^Y^, although the
angle TA^Y^ is smaller than TA^Y^-
Fig. 26.
The rules for the evolution are hence the following :
1st. The ships change course simultaneously through the angle
toward the ship farthest advanced in the direction of the advan-
tageous course, resulting thus in a column of vessels.
2d. The leading ship, followed in succession by the other ships,
changes course in the direction of the new alignment which makes
the minimum angle with the advantageous course.
3d. When the last ship has completed the turn in the wake of
the leading ship, the ships change simultaneously to the advan-
tageous course.
108
The Fundamentals of Naval Tactics.
It is to be noted that the change of course in succession, which
constitutes the second part of the evolution just described, can
be executed at evolutionary speed rather than at normal speed,
because a ship that may have fallen slightly behind may put itself
exactly in position by not following exactly in the wake of the one
that precedes it, when it makes the turn.
52. Oblique Courses. — With the method by oblique courses, as
has already been said in section 33, the extreme ship toward which
the aligntfient inclines, reduces' its speed, and the ships change
course through an angle given by an appropriate table. If the
angle of the change of course were estimated by each ship, that
is to say, if it were not sought to determine it with the aid of a
table or an instrument, it could only result in the employment of a
longer time for the evolution, without any gain in simplicity.
The angle of the change of course could be determined as indi-
cated by Admiral Morin in his profound work entitled Degli
ordini e delle evoluzioni di' tin' armata (Rivista Maritiima, 1873-
1874) ; but even in that case the evolution would not be completed
in the minimum time.
It might also be prescribed that the intermediate ships of the
formation should regulate their speed so as to arrive simultane-
ously on the new alignment; but the reasons for so doing are
insufficient, while, on the contrary, for the case in which it is
necessary to confront an unforeseen situation, it is preferable
that each ship should arrive on the new alignment as soon as pos-
sible, as was proposed by De Gueydon.
The maximum value of the speed ratio that can be adopted in
evolutions must be inferior to the value y'-j established in section
49 ; that is to say y^. On the other hand, as we have already said
in Chapter I, the minimum value that can be adopted for this
ratio is ^.
This being the case, it seems logical to perform evolutions with
the ratio -J when the rapidity of the evolution is principally re-
quired, and adopt the ratio ^ if rapidity must be sacrificed to the
condition of losing the least distance possible in the direction of
the advantageous course ; it is well, however, to make a few re-
flections in this connection.
Let us indicate by Fa the evolutionary speed, and by Vb the
speed of the pivot ship. Let t' and t" be respectively the times
109
The Fundamentals of Naval Tactics.
employed in a change of bearing of an amplitude w with the values
nula (6) o
t" Vr'
\ and y-i7 for —~- . By formula (6) of Chapter I we have :
Vr' and Vr" being the relative speeds corresponding to f and t"
that are deduced by the formula in section 31, which gives Vr ;
this formula can be written:
r.= FVi+(fy-.tcos8, ^
in which 8 is the angle of the change of course given by equation
(3) of Chapter I as a function of -^ and B. — — ; p^ being the
Vi. 2
polar bearing on which the ships are found with respect to the
pivot ship at the beginning of the evolution.
In the time t" necessary for the evolution with the ratio y\ the
space passed over by the pivot ship, which we will indicate by p",
is given by
p" = o.8VJ".
Let us bear in mind thaty'^r^Ais the normal speed ; consequently,
if the evolution is performed with the ratio ^, the track p' of the
pivot ship in the time t" is evidently
p' = o.s Fa f' + 0.9 Fa ( t" -t');
and hence we have
p"-p'=(o.4-o.i-^'jVJ'. (2)
Let us indicate the ratio- ^ " by u; the values of ~ calculated
Va^ t
with formula (i), and those of u, which are obtained by means of
(2), are assembled in the following table in which fi. — ^ is made
2
to vary from 0° to 90°, bearing in mind that with supplementary
values of ^^ — —, formula (3) of Chapter I gives values of 8 that are
equal, but with the contrary sign ; and hence the same Vr corre-
sponds thereto.
Pi- "2 "jr M
0° 1.4 0.26
30° 2.0 0.20
60° 2.4 o.i6
90° 2.5 o.is
no
The Fundamentals of Naval Tactics.
These values show that if jSj-— is included between ^o° and
2 ^
i8o°-30° = i5o°, and if the evolution is such that it is of long
duration when executed with the speed ratio ^, the advisability of
the evolution with the ratio ^ is to be excluded, because the
greater distance gained in the direction of the course appears to
be a negligible advantage when compared with the increase that
is realized in the duration of the evolution ; in other words, the
time necessary for securing the benefit represented by the differ-
ence p"—p' is so long that we cannot rely upon the tactical condi-
tions remaining stationary long enough to permit of completing
the evolution.
For example, let us suppose the speed F= i8 knots an hour, or
558 meters a minute; let 13^ =75° and ^=10 minutes, as is
the case with a fleet of ships in line abreast at intervals of 500
meters, that wishes to change the bearing through 30° ; we have,
then, f = 24 minutes (about), and />"—/)' = o.i6x558x 10=890
meters.
If pi — — is less than 30° or greater than 150°, the angle of
change 8 is greater than that which would be required, for the
same value of w, in the case before considered ; that is to say, with
respect to that case, and with the same method, the evolution is
more fapid ; and it is to be noted that f diminishes more rapidly
t"
than t' because, as the table shows, the ratio -r- diminishes while u
t'
increases ; and hence the evolution with the ratio -1*^ may really be
advantageous. For example, for the fleet of 12 ships before sup-
posed, when y8i=40° and (0 = 30°, we have f = y.^ or t"=i2 min-
utes, and />"— ^' = 0.22x558x7.5 = 940 meters.
Now let us note that in order to have /S^— " <30°, it is neces-
sary for Si to be between — and 30° 4- — ; but since, as a meas-
2 2
ure of safety, we cannot allow the course of the pivot ship to be
crossed during the evolution, ^^ must be included between m and
30° 4- -^ ; or, it must be greater than 150° -| .
Moreover, considering that it is necessary to avoid excessively
long evolutions, it is well that the evolutions with the speed ratio
The Fundamentals of Naval Tactics.
YTs should be restricted to the case in which w is not greater than
30" ; so that such evolutions, in view of the limits of 13^ just found,
may be deemed advantageous for lines of bearing nearer to the
column of vessels than to the line abreast.
When 0) does not exceed about 10°, t' is small whatever may be
the value of B-^ — ^ , and hence no importance can be attributed
2
to the difference p"—p'; however, as t" is also sufficiently small,
the evolution with the ratio ^v is justified by the possibility of
obtaining the object with the minimum alteration of course and
speed. In other words, we may in general affirm the propriety of
adopting the ratio ^ when the evolution can almost be considered
as a rectification of the formation. It is clear that in such case it
is not advisable to apply the rule of De Gueydon for the change
of course of the pivot ship ; the course of the pivot must remain
unchanged.
The evolution with the ratio ^ is then advisable when co is of
considerable amplitude, and the formation is nearer to line abreast
than to column of vessels.
53. Change of Alignment by Wheeling. — I. Admiral Bouet de
Willaumez, in his Pro jet de tactique navale (1855), in which he
laid down the basis for the evolutionary systems for steam vessels,
in considering the wheeling of a fleet drawn up in line abreast,
alluded to the system of pivoting on the center ship, one-half of
the vessels going ahead and the other half backing; naturally, he
discarded the method, since evolutions cannot be performed by
going astern, and he limited the practical methods to those which
pivot on one of the extremities of the formation. Nevertheless,
the idea of the illustrious admiral can be applied to the wheeling
of a column of vessels without need of backing the engines ; in
such case, as indicated by the anonymous writer in the United
Service Magazine already cited (section 33, III), it is possible to
change the alignment by pivoting on an intermediate ship of the
formation; or, the line may be considered as composed of two
parts, one of which has the pivot ship for a leader, and the other
has it for the rear ship ; and hence the first performs the evolution
by executing the wheel on the leading ship, while the other makes
the change of course necessary for wheeling on the rear ship.
On the basis of the idea already advanced that, tactically, it is
not important to maintain a fixed formation, we may not, in gen-
112
The Fundamentals of Naval Tactics.
eral, assign importance to wheelings ; that is to say, it is not neces-
sary at the end of the evolution to re-establish the polar bearing
that the formation had initially; however, if the wheeling of a
column of vessels can be executed rapidly by pivoting on an inter-
mediate ship, we are induced to favor this method for changing
an alignment, considering the column of vessels as a transitory
formation, as is done in evolutions performed in succession. In
other words, being upon any line of polar bearing a, in order to
change the alignment we can change the course of the ships simul-
taneously through the angle a, thus bringing them into column of
vessels, then execute the wheel on a conveniently selected pivot
ship, and afterwards, with another simultaneous change of course,
take the direction that is deemed advantageous.
In such an evolution the pivot ship evidently cannot man-
euver according to the rule of De Gueydon, because the two
parts of the line execute changes of course in contrary directions ;
hence, the pivot ship must alter the course through the angle w,
through which it is desired to change the alignment, and after-
wards reduce speed in the desired ratio with the evolutionary
speed.
After what has been said in section 33, it is easy to determine
the criterion according to which the pivot ship should be selected.
Evidently, in order to wheel a column of vessels A-^A^ (Fig- 18),
the ship B most convenient as a pivot, is the one to which there
corresponds an evolution of the same duration for each of the
extreme ships, A^ and A 2, that are respectively the rear ship and
the leading ship. Having demonstrated that --*— >i, it quickly
A2B
follows that the point of rotation is ahead of the center of the line.
In particular, from the table of section 33, IV, which, for the
speed ratio -J, gives the values of the ratio — ^ between the dura-
tion of a wheel on the rear ship, and that of a wheel on the leading
ship (or, it gives the values of ' , we may deduce the ratio
A^B I
^ ; that is, the distance of the pivot from the leading ship as
A1A2
a function of the length A^A2 of the line. In fact, we have
A^B I _^j_|_ I
A1A2 AJB J2_
^^ A2B ^ h
113
The Fundamentals of Naval Tactics.
Indicating by ^3 the duration of the wheel when pivoting on B,
it is clear ihai ^^ is equal to the ratio -^ , the values of which,
A1A2 '2
multiplied by the corresponding values of -^ given by the table of
in
section 33, IV (^0 being the duration of the evolution performed
in succession) , give us those of the ratio — .
4
In the following table are set down the values of the two above-
mentioned ratios.
tz to
15° 0.46 0.15
30" 0.42 0.29
45° 0.39 I 0.43
60° 0.36 0.55
75° 0-33 0-65
90° 0.31 0.75
These results show : ist. That with is less, the pivot ship is
the one at about four-tenths of that distance. 2d. That the method
of wheeling just cited is advantageous when compared to that
performed in succession, especially for values of ta less than 60°.
From what has been said, the ships astern of the pivot ship
should change course as in any ordinary wheel on the leading ship ;
but, for a certain number z of them, the evolution may be simpli-
fied by prescribing that they follow the pivot ship in succession on
the basis of the following considerations.
As the pivot ship, after having changed course through the
angle u>, takes up the speed ^ Fa, a ship that occupies the position z
astern of the pivot, and which follows it in succession, arrives on
the new alignment after a time z jyy ; d being the distance be-
tween two adjacent ships.
To the end that the said time may not exceed that occupied by
the last ship of the line in executing the wheel, it is necessary to
realize
iFA<
114
The Fundamentals of Naval Tactics.
Let n be the total number of ships composing the Hne. The
time that would be occupied in following the leading ship in suc-
cession at a speed Fl is expressed by
/ _ (n—i)d .
and hence we must have
= U-i )4
< 2 4'
in which the values of -^ that it is necessary to introduce are those
'0
previously obtained. Under the two hypotheses of a line com-
posed of 12 or of 8 units, the number of ships that can maneuver
in succession astern of the pivot ship is given by the following
table :
(u n=12 71=8
IS"
30° I I
45° 2 I
60° 3 I
75° 3 2
90° 4 2
So, as an illustration, with a line of 12 ships, wishing to execute
a wheel of about 90°, the first four ships and the last three must
perform the evolution at a speed Vm while the five center ships
must keep the speed ^ Vi..
In general, the difference of speed required for the center ship
and for those at the extremities shows, as is noted by the English
writer already mentioned, that this method of changing the align-
ment is particularly advisable when the limited speed of the Ueet
is due to considerable differences in the maximum speeds of the
various ships. In fact, it has already been established that the
normal speed must be -^ of the maximum speed of the slowest
unit ; it has, furthermore, been affirmed that the evolutionary speed
may be equal to the said maximum speed. This limit cannot be
exceeded in evolutions performed in succession, and in those with
oblique courses wherein one of the extremities of the formation is
made the pivot, it being necessary that the angle of change of
course be the same for all the ships. It is clear, however, that in
order to obtain the maximum rapidity in wheeling the column of
vessels by the method described, if the divisions composed of the
fastest ships are placed at the extremities, such ships can avail
"5
The Fundamentals of Naval Tactics.
themselves, not only of the reserve of speed defined in section 49,
but also that which results from the difference between the normal
speed of the fleet and the maximum speed of the said divisions.
If the ratio between the maximum speed of the central division
and the maximum speed of the extreme divisions does not exceed
y\, from what proceeds there results, within certain limits, the
possibility of wheeling the line without loss of speed to the Heet
as a zvhole, by executing the change of course a in succession with
the central division, and by the ships of the extreme divisions going
to their positions with the reserve of speed. With the speed ratio
yV this method may be held to be advisable when « does not ex-
ceed 30".
II. Let us suppose our fleet to be on any line of polar bearing a ;
let OS (Fig. 27) be the alignment, OR the course steered; and it
is desired to pass to the alignment OS', inclined to the present
alignment at the angle c and <^t being the angles given by formula (4)
and (5) of Chapter I. Let us observe, however, that the ships
being, by hypothesis, already inclined by the angle a in the direc-
tion of the new alignment, the angle of change, instead of ^r, is
e — a in the case of pivoting on the rear, and a-\-4>t when pivoting
on the head. Taking this into consideration, the evolution may
116
•c.
/
a
i\ I
The Fundamentals of Naval Tactics.
then be executed in the same manner indicated in Chapter I, for
wheeling a column, without any complication whatever ; because,
according to the case, it suffices to subtract from, or add to, the
angle of the change of course taken from the table for wheeling
the column, the polar bearing of the formation.
It is obvious that the evolution is executed analogously if the
new alignment is inclined the opposite way; thus, in Fig. 27, if
the new alignment is OS", the angle of change
for wheeling on the rear ship is a+<^c, and for
wheeling on the leading ship it is a— <^(.
Having thus generalized on the wheeling
of the line, let us look into the importance
to be attributed to such an evolution. i
The party A (Fig. 28) has an alignment
A^A^ in the direction of the course CnCn'
of the enemy's center; it makes its align-
ment rotate through an angle u>, pivoting on
the extremity A^ farthest from the adver-
sary. Since we leave it undetermined
whether, with respect to the course of the
fleet, the said extremity is farthest ahead
or farthest astern, our reasoning is general
and tends to establish the advisability of
wheeling either on the head or on the
rear.
For simplicity's sake, let us suppose that A^^ remains stationary
during the wheel ; the center C^ of A takes the position d.', and
the new inclination of the alignment, counting from the line join-
ing the centers, is A^ClC^j', which we will indicate by fl. As
Q, is an exterior angle of the triangle Ca'Cn'^i, we have
Q,=u> + Cjl'C^'A^ ; and hence S3 >«).
The advisability of wheeling upon A-^ would hence seem to
result from the fact that, while the alignment rotates through a,
it really approaches the fundamental position through an angle
greater than w ; while if the wheel were made about the extremity
A 2, the contrary would happen ; and, finally, if the rotation were
made about Q, Q would be equal to w.
In practice, in wheeling the alignment the pivot ^^ would not
remain stationary, and, by reason of its movement, the angle Q,
might be increased or diminished according to the circumstances
117
The Fundamentals of Naval Tactics.
of the case.* So, also, the wheel on the intermediate ship, as has
been said in Part I of this section, would not be made exactly
about Ci ; but all this does not weaken the general reasoning which
would lead us to believe it advantageous to take as a pivot the
extremity of the formation farthest from the enemy.
It is now necessary to determine the value of the difference
Q, —a; this is clearly at the maximum when Q, =90" ; and, A-^A,"
being the position of the alignment of the party A corresponding
to such an hypothesis, from the triangle Ca"Cn'^i we get
tan(« = -^,
S being the length of A's alignment, and r the distance C/Cn, or
the distance between the centers after the wheel. Supposing
r= 15,000 meters, and >S"=5000 meters, we have u) = 8o° (about).
Since the maximum value of the difference S3 — w is thus 10°, it
appears to be negligible, considering the rapidity with which the
alignrhent may be rotated by pivoting about one-third of the
length of the line from its head. Also, under the hypothesis
r= 10,000 meters, we have {0 = 75° (about), or JJ— (0=15°. The
importance to be attributed to the wheel when pivoting on one of
the extremities is hence restricted to that which results from the
study made in Chapter I, in which it was established that, within
certain limits, it may be preferred to the evolution in succession
when the line is very long.
As has been said, on account of the rapidity, pivoting on the
ship about one-third from the head of the line is preferable to
pivoting on one of the extremities. Nevertheless, being on a line
of polar bearing, the evolution just mentioned may be advisable,
as it avoids the initial passage to the column of vessels. Having
regard to the amplitudes of the changes of course that the method
requires it is seen that it is best to pivot on the rear ship if the
course is inclined in the direction of the new alignment, and on
the leading ship if the course is inclined in the opposite direction.
54. Angular Alignments. — The angular orders, so much es-
teemed when the ram was considered the principal weapon, seem
* If Ai were the rear ship, the angle Q would also be increased, because
the displacement of the pivot would be in the direction A^ Ai ; while, if
Ai were the leading ship, the displacement of the pivot would be in the
direction A2' Ai; on the other hand, since we know that the evolution on
the leader is more rapid than in the other case, we must conclude that we
are confronted with contradictory elements. (Author's note.)
118
The Fundamentals of Naval Tactics.
today to acquire new importance, but on a different basis, for the
reasons adduced in Chapter III of Part I (sections i8 and 20).
As we there pointed out, the angular alignments are advisable in
offensive contact for the purpose of having each of the elementary
portions of a composite alignment in fundamental tactical position.
This advisability commences in contact out of range at the
moment when the limit of offensive contact is about to be crossed,
with the application of the follow- -,,_^
ing rule, the necessity for which
seems obvious.
In contact out of range the Heel
must be on a single line, of polar \ \ j
bearing; if this is such that, when \ \ /
it is about to arrive at tiring dis- \ \ /
tance, one of the elementary align- < \ I /
ments is in fundamental position, \ \ /_
then, with such division taken as \ I /*
a pivot, the other elementary align- \i/
ment may be changed so as to es- q
tablish offensive contact in the most •„
, Fig. 29.
advantageous manner.
On the basis of this rule, under the hypothesis that the enemy
has his forces compact, the limits within which the inclination i
(Fig. 29) of the elementary alignment may vary, can be deter-
mined. Let Ci be the center of the alignment of the party A, and
let CJ and Ca" be the centers of the elementary alignments.
Evidently the maximum value of i results under the hypothesis
that the alignments must be in fundamental position with respect
to one and the same elementary alignment of the enemy's forma-
tion which has its center at Cm. In such case we have
Ca CnCa =Zr
and hence Ca'q = C/'a = QCn sin A.
2
Indicating by n the number of ships in the A party, by d the
distance between adjacent ships, and by r the distance CaCn, we
obtain
CA'CA=CA"CA=-^^^rf;
4
therefore we have
i n—id
sm-
2 4 ''
iig
The Fundamentals of Naval Tactics.
Making n= 12, ^ = 500 meters, r= 10,000 meters, we get i= 16°
(about). We may then hold j = 20° as the maximum value of i;
hence the evolution may generally be executed by oblique courses
with the speed ratio -j^. Evidently the pivot, instead of being a
single ship, is composed of all the ships of the elementary align-
ment that it is desired to leave unchanged. The fact that the
pivot is an assemblage of ships, renders inadvisable the applica-
tion of the rule of De Gueydon for the double change of course.
It is easy to understand that, in order to obtain the object of the
evolution, it is desirable that the ships forming part of the pivot
should keep a course parallel to, and in the same direction with
that of the enemy. If he makes a wide change of course, it is best
to interrupt the evolution, assume the course that is deemed best,
and then make another attempt.
When the angular alignment is brought about by the necessity
of confronting an enemy broken up into independent groups that
are not echeloned in distance — as represented in Fig. 11 — the
angle between the elementary alignments may be greater than that
just found ; in such case it is generally best to assume the angular
alignment by interrupting an evolution in succession.
55. Evolutions with a Double Alignment. — One may be induced
to perform evolutions with a double alignment (section 19), in
contact out of range, by one of the following considerations :
1st. In contact out of range, as well as in offensive contact, it
may be desired to keep the forces massed in that way.
2d. It is evident that one can perform evolutions more easily
with a simple than with a double alignment of the same length ;
but it might be held that, given a certain number of ships, by
placing them in double rather than in simple alignment, greater
evolutionary facility might be acquired by virtue of the shortening
of the line. Whenever evolutionary advantages with the double
alignment present themselves, it might be employed in contact out
of range, passing at the proper moment to the simple alignment in
order to come into offensive contact.
A fleet in double alignment may be considered as formed by
groups of four ships each in parallelogram (system of Labres *),
* See the resume of Commandante Bonamico in Rivista Marittima,
August-September, 1902.
120
The Fundamentals of Naval Tactics.
or of three ships in a triangle (system of Fournier *) ; finally by
groups of two ships, one in each line (twin system).
Let us consider evolutions performed by the ships in succession.
The maximum simplicity and evolutionary rapidity would seem
to be obtainable by causing each group of four ships to maneuver
by simultaneous changes of course ; in fact, small changes of the
course of the naval force may be obtained by having each group
make the change of course when it arrives in the wake of the
preceding group. However, it is easy to see what inconveniences
are encountered in so doing. Let us suppose a desire to change
the alignment when the ships are on
two lines of polar bearing and the
lines joining the corresponding ships
are normal to these lines of bearing,
the distance between the lines being
equal to the distances between ships,
so that each group of four ships forms
a square. By making all the ships of
the fleet on the actual alignment
change course simultaneously, we
have the double column. In Fig. 30
there is represented a fleet composed
of two groups that are already in that
formation, and there is also shown the
formation that results from a change
of course in succession, following the
rule above indicated. As is seen in
the figure, the result is that the ships
are no longer in two lines, but in four;
and it is clear that they still remain in
four lines when all the fleet executes
the simultaneous change of course in order to return to the
original course, or to take up a new course that is deemed
advantageous.
This sufficiently indicates that the method is not advisable, for
the following reason:
Fig. 30.
* See Rivista Marittima, Vol. IV of 1907. In Fournier's system, the
number of ships in one line of the alignment is half of that in the other
line. With this system simultaneous changes of course are abandoned.
(Author's note.)
121
The Fundamentals of Naval Tactics.
In offensive contact, to the end that all the ships may fire, it is
a necessary condition that they be not upon more than two lines.
When the fleet is in two lines in contact out of range, on opening
fire, it may be easy for the ships in the outer line with respect to
the enemy, appropriately to modify their positions with respect
to the ships in the inner line, so as to be able to fire through their
intervals. This already constitutes a difficulty that, in practice,
is not inconsiderable ; but plainly we shall expose ourselves to the
gravest risks if the matter is still further complicated by the fact
that the ships are in more than two lines at such a critical moment.
Analogously, if the groups of three ships each were maneuvered
by simultaneous change of course, we should
find ourselves forming three lines ; which, for
the same reasons, we believe are to be avoided.
In evolutions performed in succession, the
method of simultaneous changes of course may
be adopted with the twin system only, for
small changes of alignment. Indeed, let a, b,
a>i, fcj (Fig. 31), be four ships of the double
column ; when the ship b arrives in the water
in which a has executed the change of course,
the ship Oi is in the position a^' such that a^a^'
= a.^cD=d. To the end that, in the new align-
FiG. 31. ment, the distance between the ships of the
two lines may not fall below d, it is necessary
to have aa^' ^d, or w = 30°.
This being said, we deem it indispensable that the evolutions of
a double alignment should be executed on the basis of the follow-
ing fundamental conditions :
1st, that the fleet be always in two lines. 2d, that, in general,
the corresponding ships of the two lines should have each other
bearing normally to the alignment ; in fact, from this position the
ships of the outer line with respect to the enemy, can, at the
opportune moment and with the least possible difficulty, take the
necessary positions for firing; and in this way we shall avoid a
long alignment.
Furthermore, we shall hold that, generally, the number of ships
composing the two lines should be equal, given the essential object
which we have in view which is that of shortening the line.
The fleet may be drawn up on two lines of polar bearing a ; a
being any angle whatever, but the same for both lines. Let us
The Fundamentals of Naval Tactics.
suppose the simultaneous change of course for passing to the
double column to be already executed, as in the first position of
Fig. 30, and let us see how, and in what time, the change of direc-
tion of the said column can be completed, in order afterwards to
take up the advantageous course by a simultaneous change of
direction.
From what has been demonstrated in section 41, it results that
if two ships A and B, that have respectively the speed Fk and Vb,
keep each other constantly bearing abeam, the tracks described
by them are concentric circumferences. Letting p^, and Pb repre-
sent the radii of the circumferences AA' and BB' (Fig. 32), de-
scribed respectively by A and B when V± > Vs, and indicating by
d the distance between the two ships (which remains constant dur-
ing the movement) , from formula (11) of Chapter I, substituting
d for r therein, and making 0=^=90°, we have
d
'"'= vTZ'
Vb
while
Fa
Px = PB + d= -jf- Pb.
/ Vb
To the end that the condition pB = d may be realized, it is neces-
sary to have Vi. = 2Vb.
Now let it be noted that, between ships in formation, the tactical
radius about equal to the distance d is that which is ordinarily
employed when d is between 400 and 500 meters. It results, then,
that, when in double column, the leading ship B of the inner line,
with respect to the change of direction, puts his helm over, he must
reduce his speed to one-half that of the outer line, of which the
leading ship A, at evolutionary speed, must steer, keeping B, by
sight vane, constantly abeam. The ships of the outer line must
123
The Fundamentals of Naval Tactics.
keep up the speed in order to keep themselves abeam of their
corresponding ships.
If n is the total number of ships in the fleet, each line is then
composed of — ships ; and hence the time t occupied by the evolu-
2
tion is expressed by
-.),
Fb
{n—2)d
Fa
If, instead, the fleet were in single line, the time occupied would
be ^^~^ ; which shows that the abovementioned method re-
quires a time only slightly different from
that which would be occupied if ail the
ships were in a single line, and exactly
corresponds to the time occupied by a
single Ihta having one ship less.
The method just indicated is general,
and it is necessary to have recourse to it
when the angle <», through which it is de-
sired to change the alignment, is of con-
siderable amplitude ; but, when w is
within certain limits, one can maneuver
with greater quickness with the ratio \
between the speeds of the two lines, in
the following manner :
The ship B, leading the inner line
(Pis'- 33)' changes course through the
angle w in the desired direction, and
assumes the proper speed for the above-
mentioned ratio; the leading ship A of
the other line executes, with respect
to B taken as a pivot, an evolution by
oblique course, in order to bring itself
again on the polar bearing 90° ; that is to say, it completes — as is
said in section 33, III — a wheel in line abreast ; when A has made
the wheel, that is, when it has arrived at the position A', it steers
a course parallel to that of B and assumes the speed of B. The
ships of each line follow their respective leaders in succession, and
those of the outer line opportunely regulate their speed in order
to keep themselves abeam of their corresponding ships. It is clear,
124
Fig. 33.
The Fundamentals of Naval Tactics.
as Fig. 33 shows, that the change of direction to the new align-
ment will be completed when the last ship of the outer Hne arrives
at A' ; and, at the same time, the last ship of the inner line will
be at B.
The duration of the evolution is hence
._i2 y_ , , _ {.n-2)d
^~ o.sv^ +'°~ i.ev^ +'"
to being the time necessary for the wheel of AB.
To the end that the duration of the evolution with the method
may be less than that corresponding to the method by concentric
circumferences before alluded to, we must have
(»— 2) d , J ^ {n—2)d
1.6 V. +' • V. ■
Making — — =?(,, this inequality is transformed into another:
A Fb).
•V-
FiG. 36.
The figure corresponds to the hypothesis r=6ooo meters,
-^y- =1-5 for the usual interval of 500 meters between ships. As
Vb
shown by this, the situations of the two adversaries may be con-
sidered as equivalent; so much the more so if the speed ratio is
inferior to the one supposed.
A situation nearly like the one indicated, and which is often dis-
cussed by the students of tactics, is realized when the two leading
vessels, steering by sight vane, mutually keep each other bearing
abeam ; the radii of the circumferences are still those abovemen-
tioned, with the difference, however, that in this case r is the dis-
tance between the leading ships.
13s
The Fundamentals of Naval Tactics.
There is thus produced the tactical situation of Fig. 36, which
must be held to be advantageous for the swifter fleet for the fol-
lowing reasons: ist, the center of such fleet is removed forward
of the beam of the enemy's center ; 2d, the alignment of the said
fleet is concave, while that of the other is convex, which causes
it to befall that some ship does not present a sector of maximum
offense. Such advantages increase with the diminution of the
distance and with the increase of the ratio — ^ .
With the supposed data, as the firing distances marked in the
figure show, the swifter fleet has a sensible advantage; but the
value 77 = I -5 is certainly greater than those that are realized in
Vb
practice; we may, therefore, affirm that, in general, by making
the abovementioned maneuver, the two adversaries are in equiva-
lent tactical situations which will remain stationary. Since the
situation of the fleets is comparable to that of two single ships
opposing each other and which constantly present the beam to each
other, by analogy with what we said in Chapter II, we cannot
hold it to be rational.
We are thus in condition to affirm that, against an enemy maneu-
vering in column of vessels, we may not presume, by imitating
him, to acquire an advantageous tactical position, even if we pos-
sess a notable advantage in speed, unless we have also a notably
shorter line. Indeed, Figs. 35 and 36 show how two adversaries
that present to fire sides of opposite names may be in equivalent
positions ; it happens analogously between two adversaries who
are in fundamental position in column of vessels, with courses
parallel but in opposite directions, each of whom changes direction
in succession with intent to assume an advantageous position. In
this case the alignment of the slower party also turns its concave
side to the enemy.
It is readily seen that, for changing the distance, maneuvering
in column of vessels is hardly advisable. For such purpose, let
us consider the ships of an elementary alignment that concentrate
their fire on one of the enemy's ships. In order that the concen-
tration may be possible, it is necessary for the ship nearest the
said enemy's ship to have it bearing in a direction near the beam ;
sufficiently near, at least, to allow the most distant ship to fire in a
limit direction of a sector of maximum offense.
t36
The Fundamentals of Naval Tactics.
Let us refer to what we noted in section 37 concerning the
radii of curvature.
If the two adversaries expose to fire sides of opposite names,
the radius of curvature of the track described by the party that
maneuvers in column of vessels is necessarily very great, and
hence the track may practically be considered rectilinear for a
segment of a length equal to that of an elementary alignment.
This being the case, solving the triangle formed by the align-
ment and the two lines joining its extremities with the said
enemy's ship, it is perceived that if, for example, the sectors of
maximum offense extend to 45" from the beam, the nearest ship
must hold the said enemy's ship by sight vane in a direction at
least 60° from the longitudinal axis. In such case, the ships
maneuvering in succession in column of vessels are in the condi-
tion of a single ship whose sectors of maximum offense do not
extend farther than 30° from the beam; or, maneuvering in suc-
cession, one may not generally rely upon controlling the develop-
ment of the action.
When the two adversaries present to fire sides of the same
name, the radii of curvature are greatly reduced ; but, even if the
concavity of the alignment toward the enemy is sufficient to annul
the abovementioned inconvenience, it does not do away with the
fact that the alignment of the party that maneuvers in succession
is inclined to the line joining the centers; while, if the enemy's
alignment is in fundamental position, it is obvious that he can
oppose changing the distance by opportunely inclining his ships on
the alignment.*
* Whoever wishes to study the question in a theoretically more exact
way may profit by the knowledge of the following theorem : If two ships
steer keeping themselves on constant polar bearings, not only is the indi-
cator of relative movement an equiangular spiral, as we have already had
occasion to mention (see note to section 36), but the tracks actually fol-
lowed by the two ships are also equiangular spirals which are inclined at
the same angle with the radius vectors leading from the pole which is
common to both. The angle of inclination of the spirals, adopting the
usual symbols, is given by the formula
. Vb sin 6— Vi. sin o
tan«_ ^g cos e- Fa cos a '
It results from this that, if one of the two ships is followed by others
in succession, the alignment is on an arc of an equiangular spiral.
Lieutenant L. Tonta has occupied himself with this theorem in a valu-
able article in the Rivista Marittima of March, 1901. The question has
137
The Fundamentals of Naval Tactics.
Hence, maneuvering in succession may lead to a disadvanta-
geous situation; it lessens the capacity for tactical initiative, be-
cause in adopting it we are obliged to change the alignment, when
all that is necessary is a change of course.
Evidently, the inconveniences of the column of vessels are in-
creased with a composite alignment ; that is to say, the greater the
number of ships that follow the leading ship.
The advisability of having the ships inclined to the alignment
has been alluded to. In general, the idea of keeping the alignment
constant for considerably long intervals of time, changing the
inclination of the ships to it according to need by means of simul-
taneous changes of course, does not seem acceptable, because this
may permit an adversary who maneuvers in column of vessels to
take advantageous positions; this means, opposing a rigid align-
ment to another eminently flexible ; and, for simultaneous changes
of course, signals are rendered necessary.
It would, therefore, seem advisable to establish maneuvering in
column of vessels as normal, yet not excluding fighting on lines
of bearing because of the simultaneous changes of course that
may eventually be required ; but the defects which we have recog-
nized as attributable to maneuvering in column of vessels lead us
to seek a better system.
Maneuvering by simultaneous changes of course presents the
aforesaid inconveniences when the changes are intermittent ; but
we have already alluded (section 17) to a form of alignment (at
equidistant positions) which appears susceptible of being main-
tained in fundamental position ; let us seek to develop this idea by
procuring the elimination of the inconveniences of maneuvering
in column of vessels without falling into that of rigidity of
alignment.
We propose to see whether it is allowable to hold as normal the
maneuver known as keeping the alignment at equidistant posi-
tions, having recourse to the column of vessels as a transitory *
formation for the evolutions.
been discussed in France in divers articles published in the years 1875,
1876 and 1880 in the Revue Maritime; the results of these studies are set
forth in Chapter 11 of Manuel pratique de Cinematigue navale by Comdr.
L. Vidal (igos). In practice, however, for the length of the alignment,
the equiangular spiral may be considered as an arc of a circle the radius
of which is given by formula (11) of Chapte\' I. (Author's note.)
T38
The Fundamentals of Naval Tactics.
Such importance as a transitory formation may be admitted
without further argument, observing that, if it is necessary notably
to change the alignment, the evolution must be such as not to
render perilous the efifects of an erroneous prevision of the tac-
tical situation at its end ; or, at such a moment, it is best to be in
column of vessels. The ^volutions that we must examine for the
change of alignment in offensive contact are thus reduced to that
performed in succession and those based upon wheeling the column
of vessels (section 53).
59. Maneuvering at Eqpidistant Position. — By virtue of what
we said in section 17, an elementary alignment opposed to another
may practically be considered an arc of a circle having its center
at the center of the enemy's alignment, when, an extreme ship
Fig. 37.
being taken as the regulator, every ship is in a position such that
the angle between the line joining it with the adjacent ship in the
direction of the regulator and the line joining it with the afore-
said enemy's center, is 90°.
Supposing the ships to be on such an alignment, we propose to
study the maneuvering that permits of maintaining it.
Let us consider two adjacent ships A and A' (Fig. 37) of an
alignment at positions equidistant from N„, having as a radius
the distance r; the angle AA'N^ being 90°. Let us indicate by d
the distance AA' and by e the angle AN^A' ; we then have
sine=^.
r
Let a and a be the polar bearings on which, at the instant under
consideration, the respective ships A and A' hold N^ ; these bear-
ings being counted from the bow. If B is the polar bearing on
139
The Fundamentals of Naval Tactics.
which A is held by iV„ (counted from the stern), the analogous
bearing for A' could be ^+£ or ^ — £. We will indicate by V, V
and Fn the respective speeds of A, A' and N^-
Let us note first of all that if there exists the relations
Fsina=FNsin 6,
the indicator of movement of A with respect to TVq is given by the
joining line AN^ ; and hence, in order to preserve the alignment
in the fundamental position, the ship A' (and, more in general, the
ships of the alignment opposed to Nq) must keep the course and
speed of ^.
While not excluding the possibility that the conditions just men-
tioned may be realized in practice, it is readily seen that this
method with uniform speed and course cannot be held to be gen-
eral, because it is not logical to establish the aforesaid relation as
a necessary condition; let us, however, seek to determine the
criteria for maneuvering at equidistant positions in a way that may
permit the maximum freedom of execution. Let us see if it is
acceptable to carry out the maneuvering by the two following
methods :
1st. At uniform speed; that is to say, with the ships A and A'
maneuvering at the same speed V which, in general, naturally
requires different sight-vane angles u. and a'.
2d. With a uniform sight-vane angle, which ordinarily requires
that the ships A and A' have different speeds V and V.
In both cases the ships of the A party must move in such a way
that, in the time dt, they may have the same change dr in the dis-
tance from N^. If we wished to calculate the unknown values a'
and V it would then suffice to apply the fundamental tactical
relation. Thus, for the method at a uniform speed, we have
FnCOS ^— FcOSa=FNCOS(^±£) — Fcosa'. (i)
Naturally, when the value of cos a' supplied by this formula is
not, in absolute value, less than unity, it means that the method is
not applicable.
For the other method, in the foregoing relation it would be
necessary to put V cos a in place of F cos a ; in other words, we
may say that the value of V must satisfy the condition
F'COS a=FcOS a', (2)
wherein it is necessary to introduce the value of cos a' obtained
from (i).
140
The Fundamentals of Naval Tactics.
Applying these methods, evidently the distance AA' does not
remain invariable.
In order to fix these ideas, let us consider the simplest hy-
pothesis, which is that of a stationary enemy. Putting, in formula
(i), Fn=o, we have a' = a; which, introduced into formula (2),
gives V = V ; hence, in the particular case to which we now refer,
the two methods just mentioned are combined, the ships being
able to maneuver with uniform speed and sight-vane angle.
Against a low fort, or a ship at anchor, such maneuvering may be
opportune, because it permits the ships of a homogeneous division
to keep the enemy bearing in a direction of maximum utilization.
We may, then, in a very simple way, extend the rules estab-
lished for maneuvering an isolated ship to the maneuvering of a
division ; because such rules, in the case of a stationary enemy,
evidently lead to maneuvering at a limited distance, keeping the
enemy bearing in directions of maximum utilization alternately
forward of and abaft the beam.
In such case the joining lines AN^ and A'Nq both revolve
through the same angle, because formula (10) of Chapter I
(section 37), becomes
dc — a., or the other difference a — ^t, be sufficiently small ;
(j>c and ^t indicating, as usual, the angles corresponding to w given
in the table for wheeling the column.
When the circumstances just mentioned are not realized, the
course may be changed on the alignment, thus resulting in a
column of vessels, and the wheel executed afterwards, pivoting
at about one-third from the head of the column ; in this way a
gain in rapidity may be had, but the situation will often counsel
its abandonment because the said advantage will be negligible
when compared to the inconvenience resulting therefrom. The
English writer several times cited expresses himself in this con-
nection in the following manner : " Wheeling a column of vessels
is undoubtedly an efficacious method of changing the direction
of a long line in the quickest way possible ; but reflecting upon the
disorganization that such a change brings upon the firing of a
squadron, it must be used with extreme caution."
Moreover, in prescribing the angle through which the alignment
148
The Fundamentals of Naval Tactics.
is to be changed by wheeling, it is necessary to keep in mind the
probable counter-movement of the enemy; not taking this into
account, there might be attributed to the methods by wheeling a
greater importance than they really have ; while, in practice, such
importance is very limited.
We propose to fix these ideas by considering how such illusions
may arise.
Let us suppose that the fleet A (Fig. 39) finds itself in the
worst possible position; that is, the enemy N has succeeded in
crossing the T, and that he has taken a course parallel and oppo-
site to that of A with the object of maintaining his advantage of
position and drawing the maximum profit therefrom by diminish-
ing the distance. Let us indicate the speed of the A party by Fa.
If this party wheels his alignment through .
As has already been noted, to w = 45°, there would correspond
?2 = ^o and HCx' = S; in such case we should have
CnM = 5" sin 45 ° = 0.7S,
and hence the speed Fn necessary to allow Cn to arrive at M when
the center of A reaches Cx' would be given by
Vj^tg=o.yS,
or
Fn=o.7V^.
When o><4S'' a smaller value of Vy than this would be suffi-
cient ; this shows that, although the counter-move of N may not
be immediate, if the party N possesses a speed about equal to that
of the enemy, this speed will be sufficient to permit Cm to arrive
on the line Cx'M and even to pass beyond it. So, then, at the end
of the abovementioned wheel the party A might be in a relative
position so different from the one prognosticated as to render
another evolution necessary. In order not to run such risk the
amplitude edoes, and let us imagine that the first has a front formation,
and the other a deep formation. For example, let four be the
number of ships composing each group, and let us indicate by
iS8
The Fundamentals of Naval Tactics.
A, B, C, D (Fig. 41) the ships of the first group, and by A^, B^,
Ci, D-y, those of the second.
If, in order to consider a special hypothesis, we imagine the
first group to be formed in a square and the second in column of
vessels, as shown in the figure, it is evident that, as regards the
torpedo, the group A^, B^, Q, D^, during the passage by, will be
in better conditions than the other, because it can fire twice the
number of torpedoes.
As the same reasoning might be repeated for formations anal-
ogous to those considered, we may affirm that the object of the
maneuver in battle at close quarters, must, with
regard to the use of the torpedo, be that of oblig- c{\ {\d
ing the enemy's ships always to present the same ^ ^
side in passing by ; and inversely, each ship, bear-
ing in mind the object just mentioned, must seek a a
to pass between the enemy's ships so as to launch ^\j {j"^
the greater number of torpedoes.
It results from the foregoing that the maneuver A^^
for the employment of the torpedo in battle at ^
close quarters harmonizes with what is necessary A
for the possibility of ramming. U '
Let us now place what we have set forth in its ^
relation to the employment of the guns. ( JC',
It being admitted that, within a certain limit
of distance, the adversaries must steer for each Ax)^
other, it is well to consider this necessity in con- „
Fig. 41.
nection with the other necessity of firing with the
maximum number of guns permitted by the development of the
action ; consequently, while in long-range battle, a ship has to
keep the enemy bearing in a sector of maximum ofifense, inside
of the aforesaid limit it would be in a position which permits of
firing in the direction of the bow. Not only does the line abreast
satisfy this condition, but also any other formation in a straight
or curved line which permits the ships to fire ahead.
Summing up, we may note that, considering the three weapons
together, the best arrangement for the ships in battle at close
quarters is that which permits the simultaneous employment of
the forward guns, and differs as little as possible from the column
of vessels ; in other words, it is a question of a line of bearing that
makes a small angle with the direction of the course.
1 59
The Fundamentals of Naval Tactics.
In steering for battle at close quarters the ships of each group
must hence take, by prompt formation (any other method is evi-
dently impossible), the aforesaid position with respect to the
most advanced ship in the direction of the course ; doubtless the
distance between ships will not be the same, and, in fact, the
formation will differ in practice from a line of bearing ; but there
is no need to trouble about that. In effect, it is sufficient for the
ships to be echeloned on the side that possibly will be indicated by
the admiral, or that the situation with respect to the enemy shows
to be opportune.
Each ship of the group, after passing by the enemy, must
naturally invert the course in order to run again upon him, unless
it is prevented from making such a movement by the quick arrival
at short distance of the enemy's ships. This inversion of the
course presents no dangers of collision with friendly forces if the
ships are sufficiently echeloned in depth and the opportune side
is perfectly indicated, it being naturally the same toward which
the leading ship has turned.
If the battle at close quarters, instead of taking place between
two single groups, is general, according to the foregoing a party
moves toward it with the single groups following each other,
possibly toward the same part of the enemy, so as to obtain the
concentration of forces.
i6o
The Fundamentals of Naval Tactics.
CHAPTER V.
Torpedo-Boat Maneuvers.
66. Characteristic Conditions of the Attack of Torpedo-Boats.
— In the study of the maneuvers of ships opposing each other we
have logically held that at all times each of the adversaries seeks
to maneuver opportunely ; but the essential characteristics of the
nocturnal attack of torpedo-boats are surprise and high speed;
hence we do not reason in an entirely aprioristic way when sup-
posing that while the torpedo boats execute the maneuver of
approach, the ship attacked continues on her course. It would,
however, be erroneous to deduce from this that the maneuvering
reduces itself to solving a simple problem in kinematics ; indeed
it is necessary to keep in mind the conditions of extreme uncer-
tainty that are realized in practice. With the assistance of
Daveluy (op. cit.) let us fix our thoughts upon the difficulties that
a torpedo-boat encounters in attacking a ship in motion.
The enemy is sighted in the form of a black mass. The torpedo-
boat must take account of the direction in which its objective is
moving, and then gain an advantageous position for the maneuver
of approach ; that is to say, a position from which, steering to
arrive at launching distance, there may be assured to the torpedo
a convenient angle of impact.
This is very easy to define but very difficult to realize. When,
on sighting the ships, one is not in the aforesaid advantageous
position, in order to gain it one risks losing the benefit of the sur-
prise ; and for the rest, it is not easy to know whether one is or is
not in an advantageous position; one is led by this to steer to
approach the enemy's mass, which is hardly distinguishable, re-
serving it to himself to maneuver afterwards as he may.
In general, then, we cannot succeed in solving the problem of
approach in a theoretically exact manner; moreover, when we
have taken account of the direction in which the enemy is moving,
we still shall not have succeeded in estimating his speed, nor may
i6i
The Fundamentals of Naval Tactics.
we rely upon making this estimate in time ; which would be neces-
sary in order to construct the triangle for launching the torpedo.
From such conditions of uncertainty results the necessity of
launching from a very short distance. The improvements made
in the torpedo are to be considered as important, not because they
give the means of launching, for example, at looo meters instead
of 500, but because they confer upon the torpedo launched at the
latter distance a higher speed than it had before, and hence a
greater probability of hitting.
The results obtained by 'the Japanese torpedo-boats after the
battle of Tsushima did not depend alone upon the fact that the
artillery battle had deprived the surviving Russian ships of a part
of their means' of defense, but were due to the close and vigorous
manner in which the attacks were conducted. Togo, in his report
of the battle, expresses himself in this connection in the following
words : " According to infoi^mation gathered from the prisoners,
the attacks of the torpedo-boats during the night were extraor-
dinarily impetuous. They hurled themselves at such speed and
approacfhed so rapidly that it was impossible to stop them; they
came so close that the guns of the ship could not be sufficiently
depressed in order to hit them."
While it is necessary to remember that the real conditions of the
torpedo-boat attack will be those just mentioned, this does not
exclude the advisability of reflecting upon the theoretical condi-
tions of the maneuvering, considering them as the limit toward
which we must tend. The general criterion of launching from a
short distance being established, in the following reflections we
shall hold that the run c to be considered as normal for the tor-
pedo in a night attack of torpedo-boats is that of 500 meters.
6y. Maneuver of Approach. — It is well known that the rules
which practically apply for the maneuver of approach can be for-
mulated as follows: ist. If the torpedo-boat finds itself to one
side of the ship, it must steer as if it desired to meet that ship
(section 32, I) (lateral attack). 2d If the torpedo-boat finds itself
almost exactly ahead of the ship, in approaching it should move
somewhat to one side, and afterwards steer a course opposite that
of the ship (attack in passing on opposite courses). When the
torpedo-boat sights the ship in a stern sector, since the lateral
attack would be too long, it must first, without approaching so as
162
The Fundamentals of Naval Tactics.
to be seen by the enemy, gain a convenient bearing and then
maneuver as in the first qase.
We do not desire to create complications by seeking for different
rules, but we propose to fix our minds on the rules alluded to;
observing that, from what we have set forth in section 32, their
theoretical exactness might be placed in doubt ; and we now wish
to demonstrate that these rules are very nearly exact.
1st. If Fn is the speed of the ship N that it is desired to attack,
and V is the speed of the torpedo, as we have already had occasion
to note in section 9, the geometrical locus of the positions from
which the launching may be executed in such a way that the tor-
pedo may strike the ship after a run c is obtained by making NN^
(Fig. 42) equal to c —^ , describing a circle with a center at N^
v
and with a radius c, and then limiting to right and left of the
ships the arcs — as SS' — included between the straight lines, pass-
ing through N^, that form angles of 30° with the course.
The theoretically exact maneuver
for the approach would then be the
one for arriving on the arc SS' in
the shortest possible time. Setting
aside the angle of impact, the prob-
lem of kinematics is that of bringing
oneself in the minimum time to a
distance c from the imaginary point
ATj; and hence, if the maneuver
could be executed with theoretical
precision, from what we said in sec-
tion 32, II, on arriving at launching
distance in the shortest time, the tor-
pedo-boat should find AT^i in the
direction of its bow. In other words,
the maneuver of approach should be
executed in such fashion that, if the
torpedo-boat had a bow launching
tube, on arriving at launching dis-
tance it should have no need of
changing direction in order to exe-
cute the said launching. We note
Fig. 42.
this circumstance in order to fix the idea, and not because we at-
163
The Fundamentals of Naval Tactics.
tribute to it any special importance ; the bow tube being generally
abolished.
So, then, in order to arrive in the minimum time at the distance
c from the imaginary point iVi, it would be necessary to maneuver
(see section 32) as if it were desired to reach a point P, which is
moving at a speed Fn, and situated astern of N-^ at a distance
Ft
Vi being the speed of the torpedo-boat.
On the basis of the value of NN^, above mentioned, the point P
is distant from A^ a length NP = N^P-N^N = c(^^^ - -^
Evidently the distance NP is very small; so, putting-^ =0.8
Ft
and — = 0.5, we have
V
A^f^ 0.3c =150 meters.
We may hence conclude that, besides being easily applied practi-
cally (with the reservation mentioned in the preceding section),
the rule enunciated for the lateral attack is also very near to
theoretical exactness.
2d. Let us now suppose the torpedo-boat to be in the zone in-
cluded between the courses HH' and SK, both of which are
parallel to the course of N, and the first of which is tangent to the
circle having a radius c and its center at N-^. It is readily seen
that, if the torpedo-boat were to execute the maneuver of approach
as if it wished to reach the point P or the center N of the ship, it
might arrive at launching distance at some point of the arc SR,
and hence would not be in a position for launching with a sufficient
angle of impact. It results from this that the sure and simple
maneuver, to which corresponds a rapidity of approach differing
from the theoretical rapidity by a negligible quantity, consists in
running with a course parallel and opposite to that of the ship
attacked, when the torpedo-boat, at the beginning of the maneuver
of approach, judges itself to be laterally removed from the course
of the ship by a distance included between c and \c, or between
2^0 and §00 meters.
3d. The following considerations are sufficient to show the
necessity for the torpedo-boat to avail itself of its greater speed
164
The Fundamentals of Naval Tactics.
in order to gain a position in a forward sector of the enemy's ship
when the latter is not sighted from such a position.
The danger zone for a torpedo-boat is naturally that in which
there is great probability of being hit by the guns without being
able to launch a torpedo. Since we are referring to a night attack,
the range of the anti-torpedo-boat guns — that is to say, the radius
of the danger zone — may be held to be about 2000 meters ; and
it is to be noted that the distance at which the torpedo-boat sights
the ship is often not greater than this. The inferior limit of the
danger zone is constituted by the circle with its center at Nj^ and
the radius c (Fig. 42) , which circle moves with the ship at a speed
So, then, it is clear that the further forward is the bearing on
which the torpedo-boat begins the approach, the more rapidly will
it traverse the danger zone, for two reasons: I. The relative
speed being so much the greater, so much the more rapid will be
the variation of the distance. II. So much the greater will be the
distance at which the launching can be executed. It may be noted
that in giving importance to this we are not in opposition to the
criterion established — that of launching from a short distance. It
is very true that we may not pretend to diminish the danger zone
by launching the torpedo for a long run, because in so doing we
should obey a mistaken defensive sentiment, and we should risk
rendering our offense inefficacious. The torpedo-boat that thinks
of protecting itself instead of attacking vigorously is a torpedo-
boat lost without having accomplished anything. But in the case
under discussion the situation is different ; the term short distance
must be precisely understood in the sense of o short run for the
torpedo; and the further forward (up to the line SK) is the posi-
tion of the torpedo-boat, so much the more may we launch from a
distance, the run of the torpedo remaining as short as has been
established, without having a notable difference in the probability
of hitting.
68. The Maneuvering of a Flotilla of Torpedo-Boats. — Owing
to the characteristic difficulties of the torpedo-boat attack pointed
out in section 66, it is necessary that the attack be executed by a
certain number of units ; there being thus the possibility of pro-
ducing uncertainty in the firing of the enemy, who is obliged to
distribute his offense among the different targets ; and permitting
the hope that the number may remedy the scant probability of
165
The Fundamentals of Naval Tactics.
individual success. Nevertheless, as Commander Vannutelli has
observed {Rivista Marittima for May, 1910), it is well to consider
the following axioms :
I St. The probabilities that the torpedo-boats will be hit before
arriving at launching distance increase with the compactness of
the order of attack ; since, when the torpedo-boats are very close
together, they constitute a single, extended target, easily visible ;
and, vice versa, they diminish with the increase in the dispersion
of the torpedo-boats in the direction normal to the line of fire.
2d. The same probabilities increase with the increase in depth
of the order of attack of the torpedo-boats in the direction of the
bearing of the ship ; that is, they are maximum when the various
units keep on or near the same bearing from the ship, thus expos-
ing themselves to raking fire. It results,, therefore, that it is neces-
sary for the torpedo-boats to have a suitable dispersion, and to
arrive at the launching position simultaneously rather than suc-
cessively.
But the length of the chord SH (Fig. 42) is equal to 500 meters,
the angle SN^H being 60° ; we dedluce therefrom that the maxi-
mum number of torpedo-boats that may simultaneously attack a
ship from one and the same side, to the end that they may be prop-
erly separated, must be held to be three.
Having to aim at simultaneity of attack, the torpedo-boats of
this group, in distancing themselves from each other for the
execution of the maneuver of approach to the ship, must arrange
themselves on an alignment normal to the line joining their center
with TVj ; thus also satisfying approximately the second of the
axioms just enunciated. It can be established as a practical rule
that the alignment may possibly be normal to the line joining its
center with a point a little ahead of the ship to be attacked (the
further ahead, the higher is the speed V^)-
From this alignment, the torpedo-boat occupying the central
position may begin its maneuver of approach as if it were alone ;
and the others must follow a course parallel to it.
The action of one of these groups, which attacks the ship on one
side, evidently favors the attack of a similar group on the opposite
side, if this is made after a very short interval of time ; since,
from the moment in which it is discovered, it may be predicted
that it will absorb practically all the attention of the enemy.
There is thus developed the advisability of constituting squad-
166
The Fundamentals of Naval Tactics.
rons of torpedo-boats of six units, divided into two sections, des-
tined to maneuver for the attack separately but co-ordinately.
Evidently, the attack of the sections on the two sides can be made
on condition that the squadron, on sighting the ship, finds itself
on the line of the course of the latter ; otherwise the sections will
attack successively ; it may be presumed that the first attack, if it
does not succeed, will be an efficacious preparation for the second ;
because, in the minutes following, there will be a relaxation of
vigilance.
Such seem to be the guiding criteria, not excluding that it may
be advisable to depart from them under special circumstances, in
order to adapt oneself to the movements of the enemy, if he moves
as the searchlights are directed, toward the number and position
of the torpedo-boats illuminated.
The employment of several squadrons against a fleet of ships
requires as a preliminary condition the envelopment of the enemy ;
that is to say, taking the position with the squadrons in different
points of the horizon so that the adversary cannot withdraw from
the attack. But it is needless to say that the problem of envelop-
ment ought not to be considered a problem of kinematics ; criteria
for its solution cannot be pre-established, because the envelopment
is to be held possible only when the adversary's fleet is occupied
in an artillery battle. Typical conditions for a general attack are
those described as follows in the already cited report of Togo:
" Night was beginning to fall. Our torpedo-boat squadrons had
already enveloped the enemy to the North, East and South. Con-
sequently the principal squadron ceased fighting and withdrew at
sunset."
69. Tactical Action by Day. — Let us recall to mind the begin-
ning of the battle of August 10, 1904. The Russian squadron saw
numerous torpedo-boats ahead, and, fearing that they might have
thrown out blockading mines, changed course 90°. An action of
such nature, which obliges the enemy to make a movement not
required by the situation with respect to our battle forces, may be
of great assistance to us.
A movement of destroyers directed so as to arrive at launching
position may evidently be admitted against damaged ships, as was
done at Tsushima against the Souwaroif; it may not be excluded
with uninjured ships, on condition that the two principal fleets are
not very far apart. Indeed, by day, the danger zone for torpedo-
boats is so extended, and the fire of the medium artillery is so
167
The Fundamentals of Naval Tactics.
precise, that the launching would have to be executed from a very
long distance; and since, under such conditions, there is very
scant probability of success, it is not worth while to expose the tor-
pedo-vessels. When, however, the distance from the enemy is rela-
tively short, that is, when, for example, the two fleets are fighting
at close range, if nothing else is accomplished, the torpedo-boats
will oblige a part of the enemy's ships to make a movement not
required for its tactical employment with respect to the battle
fleet ; which may produce important consequences.
70. The Maneuvering of a Submersible. — A submersible, for an
attack by day, finds itself in conditions analogous to those of a
torpedo-boat in a night attack, with the added disadvantage of its
inferiority in speed with respect to the ship. It must submerge at
a distance of about three miles from the ship and steer for the
approach ; rectify the course by emerging the periscope, and then
execute the launching. We propose to determine the sector in
which the submersible should be found with respect to the ship at
the moment of approach, in order that conditions making it im-
possible to arrive at launching position may not exist.
Let us suppose that the submersible executes the maneuver of
approach according to the first rules indicated for a torpedo-boat ;
that is to say, it steers as if it wished to meet the ship.
Let a be the polar bearing we are seeking, or, the maximum
angle that the ship-submersible joining line may make with the
course of the ship in order to permit of approaching. Let us indi-
cate by Fn and Va the respective speeds of the ship and of the
submersible, and, naturally, let V^ be greater than Va.
From section 32, 1, there results
sina=^ ;
and hence for ^ =.^ , we have a = 42° ; for -^ =TV = i we have
a = 30°.
With the course of reasoning of section 67, in Fig. 42, we obtain
Va V /■
Making -^=0.5, we have:
V
for^=i iVP=i.5c.
168
NP^-^ ^N
The Fundamentals of Naval Tactics.
The value of the distance NP is not, then, as small as in the case
of a torpedo-boat ; and this leads us to ask ourselves how much a
may be considered as increased with respect to the values pre-
viously deduced, admitting — but not conceding — that the sub-
mersible might succeed in maneuvering in a theoretically exact
way for arriving at launching position in the minimum time.
If a is the polar bearing on which
the submersible S would be seen
from the point P in Fig. 42, the
exact value of a is evidently that
which corresponds to
sina'=-^;
^N
that is to say, there must be assigned
to a the values already deduced
for a.
Indicating by R the distance NS
(Fig. 43), at the beginning of the maneuver of approach, from
the triangle NPS we have
NP sin(a-a')
R ~ sin a' '
from which, substituting for NP and for sin a their values, we
obtain :
sm(a-a ) = -— — jrr ,
Fig. 43.
or
sm
Vs
For the two cases previously considered, the values of — ^ are
respectively i and I ; introducing them into this formula, and
putting c= 1000 meters and i? = sooo meters, we get:
for-^ =A> ct-a' = 8°; and hence = 50° (about) ;
Vs ^^
for— =4, a-a' = 9°; and hence = 39° (about).
Vv
If, then, a submersible is signalled at a distance R from the ship,
in order to prevent it from arriving at launching distance, it is
169
The Fundamentals of Naval Tactics.
sufficient for the ship to change course through an angle that
reaches the maximum values above mentioned.
This is not to be understood as denying the importance to which
a submersible may rise — it seems to us that, under present condi-
tions, we may deduce that, instead of relying upon its own maneu-
vering, the submersible ought generally to wait for the enemy to
pass within range ; that is to say, lie in ambush.
Let us express ourselves in the words with which an American
writer closes an important paper on the subject.* " The sub-
mersible is a slow and clumsy animal, but its bite is mortal. Keep
out of its way. In any case it is not as likely to get you as we have
been led to believe."
* Proceedings of U. S. Naval Institute, Vol. XXXI.
170
PART III.
TACTICAL ACTION AS A WHOLE.
CHAPTER I.
Preparation for Tactical Contact.
71. Route Formations. — The route formation of the main body
of the forces must be established with reference to the possibility
of tactical contact with battleships and of attack by torpedo-boats.
As we have already had occasion to point out in section 38, one
must bear in mind the necessity of not stretching out the ships of
the line in chain ; that is to say, they must be kept compact.
Like a fight at close quarters by day, so a night encounter be-
tween battleships will certainly not be desirable for the party that
is the superior, owing to its interest in avoiding situations in which
the unforeseeable is dominant ; but it may be advisable for the one
who desires to attempt a desperate stroke. It is necessary to guard
against such an event, a constant rule being that of not supposing
the enemy to be amenable to our designs. Consequently, in order
to establish the criteria by which the route formation should be
inspired, let us fix our minds on the modalities of the night
encounter.
The struggle at close quarters can be its only efificacious form ;
for this the considerations set forth in section 65 are of value,
according to which considerations the route formation must have
as a basis the column of vessels, echeloning the ships from it
according to the way in which the enemy presents himself. The
considerations therein developed must be admitted a fortiori,
because, naturally, by night, still more than by day, it is indis-
pensable to reduce signals to a minimum and to avoid confusion.
We must hold with Labres (op. cit.) that the action of the two
fleets will cease when they have passed each other, since a second
encounter would imply an inversion of the courses, which must be
excluded, owing to the difficulty of recognizing the ships of the
two parties. But one must still put himself in condition to draw
profit from the disorder of the enemy after passing him. For this
171
The Fundamentals of Naval Tactics.
purpose it is well to dispose the forces in two divisions, with suffi-
cient distance between them, so that they need jiot trouble them-
selves about the movements that, for each of them, may result
from the encounters with the ships or the torpedo-boats of the
enemy ; these two divisions can then attack in succession.
In this way there is established the advisability that the princi-
pal forces, if numerous, be divided at night into two divisions,
rather than massed in a single assemblage.
The route formation of each division in column of vessels is
also the most opportune, having regard to the attacks of torpedo-
boats. In fact it is well to observe that the maneuvering of the tor-
pedo-boats will be directed toward executing the attack in such a
way as to remain the shortest possible time under fire ; therefore,
the torpedo-boat will execute the attack upon the first ship that pre-
sents itself ; and only in the improbable case that he may decide it to
have been put out of action will he launch himself against the
following ship.
Bearing in mind the characteristic conditions of the night attack
of torpedo-boats (section 66), we must recognize that, practically,
it is not possible for the torpedo-boats to make a choice of the
objectives when the latter are composed — as we now suppose — of
ships in motion. The route formation in column of vessels per-
mits, then, the following advantages :
1st. The probability that the torpedo-boats may be in position
to attack with opposite parallel courses is rendered minimum ;
and if this happens, the ships can fire ahead by moving freely out
of the column of vessels and toward the opportune side as much
as may be necessary.
2d. The maximum defense can be put forth against torpedo-
boats sighted off the beam.
3d. The torpedo-boats are also placed in the worst conditions
for the withdrawal after launching the torpedoes.
When cruising by night as well as by day in a zone in which the
presence of numerous torpedo-boats is probable, aside from the
measures for safety of which we shall speak, it must be deemed
advisable to navigate at high speed. In fact, the higher the speed,
the smaller — as is well known — is the probability of hitting with
the torpedo, and the greater the difficulties for the torpedo-boats
of executing the maneuver of approach under good conditions.
The cruising system just indicated is applicable, whatever may
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TiIe Fundamentals of Naval Tactics.
be the conformation of the sheet of water that is being crossed.
The relative positions of the groups are to be determined accord-
ing to circumstances ; such positions may vary from that in which
one division follows the other at a distance, to that of two columns
abreast with an interval between the columns of four or five miles ;
that is, which permits of putting the light artillery and the search-
lights freely into action. It is naturally understood that the run-
ning lights are obscured, and that the searchlights must be put into
action only when the presence of hostile torpedo-boats is signalled.
As Commander Sechi justly observes,* in employing the search-
lights " to explore the horizon at more or less frequent intervals,
one offers great facility to hostile torpedo-boats ; because it is
much more difficult for them to find the ships and make sure of
their identity than to assail them after having discovered them."
The above-mentioned formation is the one that evidently serves
best from the point of view of safety in navigation ; it facilitates
maneuvering and secrecy, enabling signals to be transmitted be-
tween the successive ships of each division by means of a flashlight,
visible in a limited sector.
For communication between the two divisions of the naval force
the best means of signalling seems to be that of wireless teleg-
raphy, because any others might more easily serve to summon the
enemy's torpedo-boats.
The question of the order in which the ships should open fire
presents no difficulties with the adopted formation, each ship
having a clear field of fire in case of lateral approach, and being
easily able to echelon themselves in case of sighting the enemy in
the direction of the course. The important thing is that the orders
given to the units detached from the main body shall guarantee
that the ships or torpedo-boats sighted are those of the enemy;
if this necessity is satisfied it can be established that every ship
shall open fire as soon as it sights the enemy.
By night as well as by day, the cruising order to be considered
as normal for a section of torpedo-boats is that of a triangle of
suitable shape, in order that one torpedo-boat may not be en-
veloped in the smoke of another. The triangular disposition con-
fers the maximum safety in navigation, renders communication
easy, avoids the elongations that are produced in the column of
vessels, lends itself to the assumption of the opportune alignment
* Elementi di Arte Militare Marittima, Vol. II, page 420.
17.-?
The Fundamentals of Naval Tactpcs.
for the attack, and, finally, it permits of grouping in the minimum
space, or it is adapted to keeping the torpedo-boats under the sup-
port of the ships.
It may be advisable for a flotilla to navigate with the two sections
in formation different from that of a column, as Commander Van-
nutelli has proposed in the article already cited. " In column of
vessels and with high speed, it is easy to lose contact, or, vice versa,
to have dangerous closings in, especially when navigating with
lights obscured ; that is to say, when about a hundred meters of
distance is enough for losing sight of the stprn of the preceding
torpedo-boat, while in lines abreast or oblique lines it is much more
difficult to lose sight of the dark lines of the entire length of the
adjacent torpedo-boat. Every one will remember the intense
watchfulness and the continual variations of speed that the column
of vessels requires by night, which, therefore, in a short time
brings great fatigue. With frontal orders the squadron is pre-
sented well subdivided into two t'actical groups, ready to separate
for the opportune maneuver."
72. Scouting.-^As is well known, we mean by tactical explora-
tion that which is exercised by ships in direct communication with
the main body, remaining in contact with it at a distance such as to
permit a discreet reliance on being able to regain it when it passes
to tactical contact with the enemy's battle forces. It is well for
this reliance upon the reunion with the main body to be so much
the greater, the greater is the tactical importance of the ships
employed ; that is to say, the greater the importance of these ships,
the shorter should be their distance from the main body. Only in
exceptional cases could it be desirable for the battleships to sight
directly those of the enemy; thus, when in the Chino- Japanese
War, Admiral Ito moved in search of the fleet of Ting at the
mouth of the Yalu, he was not preceded by any ship, because he
aimed at surprising the enemy. But he was able to rely upon the
inertness of the Chinese; in general, however, it is presumable
that the enemy will maintain a scouting service, especially if he is
occupied in operations owing to which he might, by our unex-
pected arrival, be placed in a critical position ; and then comes the
necessity of being preceded by ships that will seek to repulse the
enemy's cruisers, preventing them from establishing contact with
our main body ; that is to say, from comprehending the importance
of the danger that menaces their fleet.
174
The Fundamentals of Naval Tactics.
The importance of knowing beforehand of the approach of the
enemy's fleet really exists, as we shall endeavor to show ; but it is
well to consider in what degree we may be able to satisfy it, if it
cannot be presumed in what direction the enemy will be sighted.
If we should pretend to form with the tactical scouts a continuous
line about the main body, either we should have to employ many
units, or the radius of the explored zone would be greatly
restricted. '
It results from this that tactical exploration, like strategic
exploration, must have for its object the search for the main body
of the enemy's forces, having regard, however, to certain limits
of distance from one's own body. To the end that the warning
may not be illusory, it is well to abandon the certainty that the
scouts will encounter the enemy before the main body does so, and
be content with only a probability. A lookout service tending to
establish almost absolute safety over a sufficiently wide sector
about the main body is, however, required when the presence of
numerous torpedo-boats can be expected in the sheet of water to be
traversed. In such service the vessels destined for tactical scout-
ing assist; they constitute a first line of defense which, for the
reasons mentioned, cannot be entirely relied upon ; it is necessary,
however, to guard oneself effectively, which can be done in the
following manner, on the basis of the deductions of the preceding
chapter :
Remembering that the torpedo-boats sighted astern are the
least dangerous, it is necessary, by night, to have the naval force
preceded and flanked by groups of torpedo-boats at a distance
from the main body such that the searchlight of the ships may be
operated upon occasion without illuminating them. Each section
of torpedo-boats must cruise in compact formation in order to be
ready to attack the enemy's forces that it may encounter. The
greater cruising speed may be utilized by making these groups
traverse a zig-zag with sides suitably inclined to the course of the
main body. These torpedo-boats must signal the approach of
those of the enemy and try to drive them back, without coming
within range of the light guns of their own ships, since every ship
must necessarily be able to fire upon any torpedo-boat that ap-
proaches it.
In order to exercise vigilance by day against submersibles, it is
necessary for the destroyers to keep a lookout ahead and on each
1 75
The Fundamentals of Naval Tactics.
side (up to about 45° from the course) extending themselves in
chain. It would be desirable to have a chain at three miles and
qae at five miles ; that is to say, within the limits at which the
submersibles must begin the maneuver of approach.
73. The Reconnoitering of the Adversaries.^— Although it may
not be excluded, it is nevertheless not very probable that the fig-ht-
ing forces will sight each other directly ; indeed, even admitting
that only one of the hostile fleets carries out tactical sffouting, when
its scouts arrive in sight of the enemy, the latter will detach ships
to drive them away, in order to prevent their maintaining the
contact ; and, as in the case wherein the scouting is carried on by
both the adversaries, an action between cruisers will precede the
battle.
It might be said that this statement is contrary to experience ;
the encounter between cruisers has not yet been produced, not-
withstanding three successive wars ; but we can easily give reasons
why this may have been the case. For the Chino-Japanese War
the consideration already advanced will serve ; for the Hispano-
American War, the battle took place between a division of four
ships and a squadron that was blockading it, keeping with all its
ships in close proximity to the entrance of the port. Finally,
for the Russo-Japanese War, it is well known that the Japanese
main body was constantly preceded by the cruisers ; the battle of
Tsushima would have begun as above stated if Rojestvensky had
had the means of fighting the enemy's cruisers. But, as Semenoff
observes in Rassplata, the Russian cruisers were either too weak
or very old and with insufficient speed. " Furthermore, the ad-
miral desired to save and keep all the elements together ; the more
so, since, the 12 armored ships being engaged with the 12 Japanese
armored vessels, the cruisers would have had to protect the trans-
ports and engage by themselves all the rest of the Japanese fleet."
When the encounter between cruisers takes place, the party that
has the greater strength in ships of this class, by obliging the
enemy's cruisers to turn back, obtains the singular advantage of
being able to regulate its own maneuvers of approach on the basis
of information transmitted to it; while the enemy remains in
uncertainty. In this way there is produced the situation that
beyond dispute was realized at the beginning of the battle of
Tsushima. Togo, after having stated that his cruisers reconnoi-
tered the enemy without difficulty, adds the following : " These
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The Fundamentals of Naval Tactics.
divisions, although cannonaded from time to time by the enemy,
succeeded in preserving the contact, sending by telegraph fre-
quent and precise new^s concerning his position. And thus, not-
withstanding a thick fog that did not permit of seeing further than
five miles, we were able to know the position of the enemy,
although he was 30 or 40 miles away, as exactly as if we had seen
him with our own eyes It was thus possible for me to
make the dispositions for finding myself at about 2 o'clock near
Okinoshima and to attack the head of the column on the port
side."
The development of an action of growing importance between
the cruisers will induce the main body to detach a sufficient force
to complete the reconnaissance. In order to fix in our minds how
this may happen, let us make use of an example.
A scout has sighted a ship ; it moves to observe it and informs
the nearest friendly ships of it by wireless telegraph, which ships
transmit the news to the commander-in-chief. The suspected
ship also has headed toward our scout, so that the recognition is
quickly accomplished; the vessel sighted is a protected cruiser
of the enemy, weaker than our own, and, consequently, at a dis-
tance of not less than 7000 meters it turns to run. The comman-
der-in-chief does not consider this of sufficient importance to alter
the course of the main body. The chase of the cruiser continues
for some time and our ship gains upon the enemy, so that there is
hope of making a good stroke.
A few ineffectual shots have already been exchanged by the
two ships, when suspected ships appear upon the horizon, and very
soon they are seen to be enemies. It is now the turn of our cruiser
to run. It is is well to mention that when our cruiser was increas-
ing its distance from the main body, another ship was moving so
as to maintain a chain with it for the transmission of news. When
the new enemy's ships are reported, there is then on our part a
concentration of a division of protected cruisers in the direction
of the adversary ; thus we have again a preponderating force and
the enemy again turns to run. The course of the main body is
somewhat inclined in that direction and the appearance of new
ships on the horizon decides us to effect a reconnoissance ; that is,
to determine if there are other principal forces' of the enemy at
hand besides those sighted. For this purpose it is determined to
send out toward the adversary forces that will not be obliged to
177
The Fundamentals of Naval Tactics.
give way except before the enemy's main body; in other words,
the armored cruisers are sent forward at that time, at full speed,
and the battleships follow ready to support them. The appearance
on the horizon of a new division of the enemy still further con-
firms the idea that important forces are to be found in that direc-
tion, and, indeed, in the new division, we recogfnize the enemy's
armored cruisers. The inferiority of the enemy in ships of this
type is not slow in producing its effect ; the adversary, in order not
to be beaten in detail, must turn back and seek the protection of
his battleships, that are sighted a little afterward. The object of
the reconnoissance is attained ; our ships take up a course parallel
to that of the enemy and at his speed, signalling to the commander-
in-chief the composition and the formation of the enemy's force ;
our admiral is thus in condition to make the necessary arrange-
ments for attacking the enemy in the most opportune way, or to
reverse the course if he does not wish to accept battle. Then
begins the contact out of range.
178
The Fundamentals of Naval Tactics.
CHAPTER II.
The Battle.
74. The Importance and Character of Naval Battle. — As Maka-
roff writes, " the loss of ten ships in as many combats has not the
moral effect of the loss of a squadron, although the number of
ships lost may not reach ten."
The destruction of the enemy's movable forces constitutes the
essential object at which we must constantly aim; pretending to
secure the object of the war by avoiding battle between the forces
and seeking secondary objectives is shown by history and deductive
reasoning to be entirely erroneous ; to us Italians it brought forth
Lissa. A battle desired is greatly preferable to a battle sub-
mitted to.
These axioms, that should be taken as the basis for the strate-
gic employment of the fleet, impose engaging tactically with the
enemy's movable forces whenever possible, and, conformably to
what we set forth in section 23, they impose engaging to a finish
as far as the strategic situation permits.
A characteristic of naval battle is, that in it the constitution of
a reserve cannot be admitted in the sense that it is understood on
land. This difference is easily explained.
On land, when the battle begins, the strength of the enemy is
not exactly known; it is not known where his principal mass
gravitates ; and in order to be in condition to face the situation at
the moment it becomes clear, it is necessary to keep available a
force to be hurled in an advantageous direction. Moreover, the
idea of the gradual employment of the forces is logical, it being
that of having troops that serve to support others already engaged,
because the latter, besides the losses that they sustain, use up their
energy; and hence it is in a high degree important to be able to
dispose of fresh troops at the opportune moment, to be despatched
in aid of the others.
It is, however, useful for our purpose to remember that even
on land it would be dangerous to give too much importance to the
criteria just mentioned. " Every reserve," writes Von der Goltz
(La Na-zione armata), " represents a dead force. Since the
simultaneous employment of all the forces brings out the maxi-
mum efficiency, it would generally seem erroneous to constitute
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reserves ; but there is need of them in order to be able to meet
unexpected incidents and sudden turns in the combat that are
never lacking. If the situation is still more uncertain, if it is
believed, for instance, that we may be exposed to many surprises,
then strong reserves will be necessary. The safer the situation,
and the better able we are to estimate concerning the enemy, the
weaker the reserves may be. We can even imagine a circumstance
in which it would be logical to proscribe them; that is, when the
enemy is completely displayed. Now, such circumstances will
certainly never be realized in practice, and, therefore, we ought
never to fight without reserves. It is certain, however, that the
opportune reserves are not always the heavy ones, but those that
respond to the situation in which we find ourselves."
In the galley period, owing to the fact that a part of the vessels
could sometimes be concealed, that the motive power was muscu-
lar, and that men fought hand to hand, there were presented con-
ditions analogous to those of battle on land. But to-day the
situation is far different ; in naval battle we find ourselves in the
ideal conditions in which, as Von der Goltz observes, reserves
could be excluded even on land.
It might seem advisable to constitute a reserve formed of anti-
quated ships with scant protection, keeping them on the side of the
alignment away from the enemy, and far removed from him so
as to safeguard them. Their mission would be to attack injured
ships of the enemy that might attempt to withdraw from the
combat. But, ideas of this nature, if they were adopted, might
bring about a repetition of the conduct of Albini's squadron on the
unfortunate day of Lissa ; let us remember that it was then said
and repeated that wooden ships could not engage with hostile
armored vessels. It would be better to leave the antiquated ships
in port, or have them previously stricken from the list, rather than
take them out before the enemy for the sole purpose of safeguard-
ing them and confiding to them an illusory objective.
When it is deemed advisable to take into battle a few antiquated
ships, because the offense of which they are capable is not to be
despised, and because their speed is sufficient not to lessen the
maneuvering qualities of the fleet, it is indispensable that they
take a direct part in the battle, and only compatibly with this may
they be safeguarded.
More generally, it is well to exclude the idea that while one part
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The Fundamentals of Naval Tactics.
of the ships is fighting, another part may remain in waiting; in
such fashion we should offer to the enemy the means of beating
our forces in detail ; and a disastrous moral effect would be pro-
duced in the ships of the reserve. Indeed, let us figure to ourselves
what was the state of mind of the personnel of the Russian cruis-
ers at the battle of August lo, 1904, when, after the injuries sus-
tained by the Askold, they were placed behind the armored ships.
The supreme importance of the battle demands that all the
ships that have the gun for a principal weapon, shall fight from
the start, assigning, however, to the various kinds of ships an
adequate objective.
It is well known that Nelson, in the memorandum for Trafalgar,
alluded to composing a division of the fastest sailers of the fleet,
reserving it to himself to indicate, according to circumstances, to
which of the two divisions it should join itself ; with the intention,
however, that the said division should participate in the battle
without delay.
The vessels to be kept in waiting are limited to the destroyers
and the torpedo-boats. It is not excluded that this light flotilla
may render some service (section 69) in the phase of tactical
evolutions ; during the fleet action it will be kept in opportunely
selected coast positions when the battle is developed in proximity
to a friendly shore, otherwise they will be kept under the protec-
tion of the ships, or at a convenient distance, according to the
employment that is had in view for them.
In determining the mission to be assigned to the various kinds
of ships, it must be borne in mind that the issue of the battle
depends upon the combat between the armored fleets. It would,
therefore, be absurd initially to withdraw from such category any
ship that has protection sufficient for taking part in the principal
combat without excessive risk, or that, although having inferior
protection (antiquated ships), has a powerful armament; in the
latter case it will be placed in the outer line but close to the other
ships so as to be able to fire in their intervals.
A few light ships will be necessary out of the line, on the side
away from the enemy, in order to repeat signals ; it may be advis-
able to have a repeating ship for every six ships of the line of
battle. The other unarmored ships, formed into a fleet indepen-
dent of the principal one, will have the task of engaging with
similar ships of the enemy ; so that it is to be presumed that, as at
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Tsushima, there will take place a secondary combat simultaneously
with the principal one.
75. Contact out of Range. — The party whose cruisers have
established contact with the enemy's main body, according to what
is said in the preceding chapter, prepares for battle on the basis
of their information ; or it alters the cruising formation as may be
necessary, and steers so as to sight the enemy from an advan-
tageous position.
If the conditions of visibility were limited, so that the distance
of sighting the enemy were within the limit of oflFensive contact,
the advantage in this way would be very great. Nevertheless,
under good conditions of visibility the enemy will generally have
time to assume an equivalent alignment. The evolutionary phase
will then begin.
In Chapter III, of Part II, we endeavored to make it plain that
it may be presumed that a phase of active maneuvering will take
place out of range, with the object of securing an initial advan-
tageous position. In contrast with the arguments therein adduced
there could be cited a phrase of Nelson : " Between two fleets
that desire to come to battle, the necessary maneuvers will be few ;
it will be desirable to make as few of them as possible.''
Let us observe that Nelson was referring to the fleet of Ville-
neuve, which, it was to be presumed, would maintain a passive
line of conduct, and that, naturally, he was not neglecting to pre-
scribe the maneuver of approach so as to secure an advantageous
position. Under analogous conditions, there is no doubt that the
simpler and more rapid the maneuver of approach, the better it
will be. Maneuvers out of range are a means of beginning the
battle well, and they do not constitute a finality ; hence they are
absurd if they are not necessary. But if the enemy maneuvers
so as to dispute with us the advantageous position which Nelson
was not hindered from taking, it will be necessary for us to maneu-
ver also, or resign ourselves to performing the part of Villeneuve.
76. Offensive Contact. — After the signal has been made at the
beginning of offensive contact to indicate the guiding principle
of the maneuver, other signals cannot be absolutely excluded,
because it would be absurd for an admiral to renounce expressing
his ideas when it is possible and necessary ; hence it is natural that
there should be battle signals, provided that they are simple and
limited in number, and can easily be memorized.
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The Fundamentals of Naval Tactics.
If the commander-in-chief is on a ship in Hne with the others,
he is exposed to great dangers, it being presumable that the said
ship will be the principal object for the concentration of fire. But
it would certainly not be logical to revert, for that reason, to the
solution adopted by the French after De Grasse was made prisoner
at the battle of the Saintes, that is, to the system of placing the
commander-in-chief on a light ship out of the line — a system they
were obliged to abandon.
Tactical maneuvers must, as we know, be based essentially upon
the following of movements ; so, then, if the commander-in-chief
were out of the line, it would be necessary to depend exclusively
upon his signals.
To the end that the commander-in-chief may have a well-
grounded hope of exercising his directive functions, it is necessary
for him to have a means analogous to that which is available on
land by means of the reserve ; that is, it is necessary for him to have
a division under his immediate orders.
Now, we bear in mind that, in tactical maneuvering, the regu-
lating ships of all the divisions are those at the extremities ; in
order to render minimum the necessity for signals, it is then neces-
sary that there be an admiral at the extremities of the formation
of each division. In order that the inconveniences may be mini-
mum in case the commander-in-chief is disabled, it is necessary
in such circumstances for his division to continue to be the regu-
lator ; that is to say, it is well for the second admiral of the divi-
sion under the direct orders of the commander-in-chief to be the
second in command of the fleet.
It might be held desirable, still satisfying the above-mentioned
condition, that, in a line formed, for example, of 12 ships in two
divisions of six ships each, the second in command be at an ex-
tremity and the commander-in-chief in the center ; but we believe
he would repent having yielded the position of honor, as Farragut
repented it at Mobile.
Having to fight a fleet more powerful than our own, it might
seem desirable to seek battle under the forts, in order to find in
their support a compensation for our own inferiority. But this
would dangerously hamper the strategic employment of the fleet,
as well as its tactical employment; and these hindrances might
carry with them such detriment as to overbalance the gain in
offensive power constituted by the action of the forts.
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The Fundamentals of Naval Tactics.
The issue of offensive contact will not depend upon maneuver-
ing and ability in firing alone, but moral factors will have great
part in it.
We can never be sufficiently imbued with the fact — examples of
which are not lacking in history — that often one is beaten solely
because he is persuaded that he is beaten. Daveluy justly affirms
that he who engages in battle with' the firm determination of not
yielding, is already half a conqueror. On the contrary, he who
goes into battle believing that he is accomplishing a useless sacri-
fice, will hardly succeed in finding energy to give rational direction
to the conduct of the forces. Defeat in that case will not be
glorious, since, although the situation may be most desperate, there
always exists a rational plan to be adopted.
Battle serves to create between combatants differences in order,
in material and in morale ; in the pursuit we may gather the fruits
of such differences and accentuate them in much greater pro-
portion.
The separation of the forces for the pursuit depends upon the
separation of the enemy's forces. When, during the night that
follows the battle, contact with the enemy is lost, owing to the
necessity of leaving a clear field for the action of the torpedo-boats,
it will be endeavored, on the following morning, to re-establish
the contact, profiting by our conditions of superiority so far as to
abandon, at least in part, those precautions that would be indis-
pensable against an enemy in full efficiency. Even the battleships
may then be extended in chain for the search.
yj. Tactical Exercises. — The tactical skilfulness of a fleet can
be obtained only through frequent exercises with parties opposing
each other. As a preparation for these exercises at sea, the tacti-
cal game may be profitable ; nevertheless, the profitable return of
this game is somewhat limited for various reasons, among which
are the impossibility of reproducing in themthiej^teegnghy- sjght
vane, and, more generally, the impossibilitf^ftf i«gulM^^^egelf
by the enemy in a continuous manner.
To the end that the tactical exercises may be conclusive, it is
indispensable that those who are called upon to execute them
should possess a sufficient substratum of theoretical knowledge.
THE END.
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