Full Text Archive logoFull Text Archive — Books, poems, drama…

Aeroplanes and Dirigibles of War by Frederick A. Talbot

Part 2 out of 4

Adobe PDF icon
Download this document as a .pdf
File size: 0.4 MB
What's this? light bulb idea Many people prefer to read off-line or to print out text and read from the real printed page. Others want to carry documents around with them on their mobile phones and read while they are on the move. We have created .pdf files of all out documents to accommodate all these groups of people. We recommend that you download .pdfs onto your mobile phone when it is connected to a WiFi connection for reading off-line.

CHAPTER VII
AEROPLANES OF WAR

Owing to the fertility of inventors and the resultant
multiplicity of designs it is impossible to describe every type
of heavier-than-air machine which has been submitted to the
exacting requirements of military duty. The variety is infinite
and the salient fact has already been established that many
of the models which have proved reliable and efficient under
normal conditions are unsuited to military operations. The early
days of the war enabled those of doubtful value to be eliminated,
the result being that those machines which are now in use
represent the survival of the fittest. Experience has
furthermore emphasised the necessity of reducing the number of
types to the absolute minimum. This weeding-out process is being
continued and there is no doubt that by the time the war is
concluded the number of approved types of aeroplanes of military
value will have been reduced to a score or less. The
inconveniences and disadvantages arising from the utilisation of
a wide variety of different types are manifold, the greatest
being the necessity of carrying a varied assortment of spare
parts, and confusion in the repair and overhauling shops.

The methodical Teuton was the first to grasp the significance of
these drawbacks; he has accordingly carried standardisation to a
high degree of efficiency, as is shown in another chapter. At a
later date France appreciated the wisdom of the German practice,
and within a short time after the outbreak of hostilities
promptly ruled out certain types of machines which were regarded
as unsuitable. In this instance the process of elimination
created considerable surprise, inasmuch as it involved an embargo
on the use of certain machines, which under peace conditions had
achieved an international reputation, and were held to represent
the finest expression of aeronautical science in France as far as
aeroplane developments are concerned.

Possibly the German machine which is most familiar, by name, to
the general public is the Taube, or, as it is sometimes called,
the Etrich monoplane, from the circumstance that it was evolved
by the Austrian engineer Igo Etrich in collaboration with his
colleague Wels. These two experimenters embarked on the study of
dynamic flight contemporaneously with Maxim, Langley, Kress, and
many other well-known pioneers, but it was not until 1908 that
their first practical machine was completed. Its success was
instantaneous, many notable flights being placed to its credit,
while some idea of the perfection of its design may be gathered
from the fact that the machine of to-day is substantially
identical with that used seven years ago, the alterations which
have been effected meanwhile being merely modifications in minor
details.

The design of this machine follows very closely the lines of a
bird in flight--hence its colloquial description, "Taube," or
"dove." Indeed the analogy to the bird is so close that the ribs
of the frame resemble the feathers of a bird. The supporting
plane is shaped in the manner of a bird's distended wing, and is
tipped up at the rear ends to ensure stability. The tail also
resembles that of a bird very closely.

This aeroplane, especially the latest type, is very speedy, and
it has proved extremely reliable. It is very sharp in turning
and extremely sensitive to its rudder, which renders it a
first-class craft for reconnoitring duty. The latest machines
are fitted with motors developing from 120 to 150 horse-power.

The "Taube" commanded attention in Germany for the reason that
it indicated the first departure from the adherence to the French
designs which up to that time had been followed somewhat
slavishly, owing to the absence of native initiative.

The individuality of character revealed in the "Taube" appealed
to the German instinct, with the result that the machine achieved
a greater reputation than might have been the case had it been
pitted against other types of essentially Teutonic origin. The
Taube was subsequently tested both in France and Great Britain,
but failed to raise an equal degree of enthusiasm, owing to the
manifestation of certain defects which marred its utility. This
practical experience tended to prove that the Taube, like the
Zeppelin, possessed a local reputation somewhat of the paper
type. The Germans, however, were by no means disappointed
by such adverse criticism, but promptly set to work to eliminate
defects with a view to securing an all-round improvement.

The most successful of these endeavours is represented in the
Taube-Rumpler aeroplane, which may be described as an improved
edition of Etrich's original idea. As a matter of fact the
modifications were of so slight, though important, a character
that many machines generically described as Taubes are in reality
Rumplers, but the difference is beyond detection by the ordinary
and unpractised observer.

In the Rumpler machine the wings, like those of the Taube, assume
broadly the form and shape of those of the pigeon or dove in
flight. The early Rumpler machines suffered from sluggish
control, but in the later types this defect has been overcome.
In the early models the wings were flexible, but in the present
craft they are rigid, although fitted with tips or ailerons. The
supporting truss beneath the wings, which was such an outstanding
feature of its prototype, has been dispensed with, the usual
I-beam longitudinals being used in its stead. The latest
machines fitted with 100-120 horse-power Mercedes motors have a
fine turn of speed, possess an enhanced ascensional effort, and
are far simpler to control

Other German machines which are used in the military service are
the Gotha and the Albatross. The former is a monoplane, and here
again the influence of Etrich upon German aeroplane developments
is strongly manifested, the shape of the bird's wing being
retained. In the Gotha the truss which Etrich introduced is a
prominent characteristic. The Albatross is a biplane, but this
craft has proved to be somewhat slow and may be said to be
confined to what might be described as the heavier aerial
military duties, where great endurance and reliability are
essential. As the war proceeds, doubtless Teuton ingenuity will
be responsible for the appearance of new types, as well as
certain modifications in the detail construction of the existing
machines, but there is every indication that the broad lines of
Etrich's conception will be retained in all monoplanes.

There is one point in which Germany has excelled. Wood is not
employed in the construction of these heavier-than-air craft.
Steel and the lighter tough alloys are exclusively used. In this
way the minimum of weight consistent with the maximum of strength
policy is carried out. Moreover the manufacture of component
parts is facilitated and accelerated to a remarkable degree by
the use of metal, while the tasks of fitting and repairing are
notably expedited by the practice of standardisation. Germany is
also manifesting commendable enterprise in the perfection of
light powerful motors for these dynamic machines. The latest
types of explosion-motors range from 100 to 150 horse-power; the
advantages of these are obvious.

Upon the outbreak of hostilities the French possessed an enormous
number and variety of aeroplanes and this aerial fleet had been
brought to a high standard of organisation. The aerial fleet is
sub-divided into squadrons called "escadrilles," each of which
comprises six machines and pilots. These units are kept up to
strength, wastage being made up from reserves, so as to maintain
the requisite homogeneity.

But ere the war had been in progress many weeks an official order
was issued forbidding the employment of the Bleriot, Deperdussin,
Nieuport, and R.E.P. monoplanes. Those which received official
approval included the Caudron, Henry, and Maurice Farman,
Morane-Saulnier, and Voisin machines.

This drastic order came somewhat as a thunderbolt, and the
reason for the decree has not been satisfactorily revealed.
Suffice to say that in one stroke the efficiency and numerical
strength of the French aerial navy were reduced very appreciably.
For instance, it is stated that there were thirty escadrilles of
Bleriot monoplanes together with pilots at the front, in addition
to thirty mixed escadrilles of the other prohibited types with
their fliers. Moreover a round 33 escadrilles of all the various
types were in reserve. The effect of the military order was to
reduce the effective strength by no fewer than 558 aeroplanes.

Seeing that the French aerial force was placed at a great
disadvantage numerically by this action, there seems to be ample
justification for the hostile criticism which the decree of
prohibition aroused in certain circles, especially when it is
remembered that there was not an equal number of the accepted
machines available to take the place of those which had been
ruled out of court. One effect of this decree was to throw some
400 expert aviators upon the waiting list for the simple reason
that machines were unavailable. Some of the best aviation skill
and knowledge which France possesses were affected by the order.
It is stated that accomplished aviators, such as Vedrines, were
unable to obtain machines.

It will be seen that the ultimate effect of the French military
decree was to reduce the number of types to about four, each of
which was allotted a specific duty. But whereas three different
bi-planes are on the approved list there is only one monoplane--
the Morane-Saulaier. This machine, however, has a great turn of
speed, and it is also able to climb at a very fast pace. In
these respects it is superior to the crack craft of Germany, so
that time after time the latter have refused battle in the skies,
and have hurried back to their lines.

The Morane-Saulnier is the French mosquito craft of the air and
like the insect, it is avowedly aggressive. In fact, its duties
are confined to the work of chasing and bringing down the enemy,
for which work its high manoeuvring capacity is excellently
adapted. Its aggressive armament comprises a mitrailleuse.
Unfortunately, however, the factory responsible for the
production of this machine is at present handicapped by the
limitations of its manufacturing plant, which when pushed to the
utmost extent cannot turn out more than about ten machines per
week. No doubt this deficiency will be remedied as the war
proceeds by extension of the works or by allotting orders to
other establishments, but at the time of the decree the
manufacturing capacity was scarcely sufficient to make good the
wastage, which was somewhat heavy.

As far as biplanes are concerned the Caudron is the fastest in
flight and is likewise extremely quick in manoeuvring. It is a
very small machine and is extremely light, but the fact that it
can climb at the rate of over 330 feet per minute is a distinct
advantage in its favour. It supplements the Morane-Saulnier
monoplane in the specific duty of the latter, while it is also
employed for discovering the enemy's artillery and communicating
the range of the latter to the French and British artillery. In
this latter work it has played a very prominent part and to
it is due in no small measure that deadly accuracy of the
artillery of the Allies which has now become so famous. This
applies especially to those tactics, where the field artillery
dashes up to a position, discharges a number of rounds in rapid
succession, or indulges in rafale firing, and then limbering up,
rushes away before the enemy can reply.

As is well known the Farman biplanes possess high endurance
qualities. They can remain aloft for many hours at a stretch and
are remarkably reliable. Owing to these qualities they are
utilised for prolonged and searching reconnoitring duties such as
strategical reconnaissances as distinct from the hurried and
tactical reconnaissances carried out by fleeter machines. While
they are not so speedy as the monoplanes of the German military
establishment, endurance in this instance is preferable to pace.
A thorough survey of the enemy's position over the whole of his
military zone, which stretches back for a distance of 30 miles or
so from the outer line of trenches, is of incalculable value to a
commander who is contemplating any decisive movement or who is
somewhat in doubt as to the precise character of his antagonist's
tactics.

The French aerial fleet has been particularly active in its work
of raiding hostile positions and submitting them to a fusillade
of bombs from the clouds. The machine which is allotted this
specific task is the Voisin biplane. This is due to the fact
that this machine is able to carry a great weight. It was
speedily discovered that in bomb-raids it is essential for
an aeroplane to be able to carry a somewhat large supply of
missiles, owing to the high percentage of misses which attends
these operations. A raid by a machine capable of carrying only,
say, half-a-dozen projectiles, is virtually a waste of fuel, and
the endurance limitations of the fast machines reacts against
their profitable use in this work. On the other hand, the fact
that the Voisin machine is able to carry a large supply of bombs
renders it an ideal craft for this purpose; hence the official
decision to confine it to this work.

So far as the British efforts in aerial work are concerned there
is no such display of rigid selection as characterises the
practice of the French and German military authorities.
Britain's position in the air has been extensively due to private
enterprise, and this is still being encouraged. Moreover at the
beginning of the war Britain was numerically far inferior both to
her antagonist and to her ally. Consequently it was a wise move
to encourage the private manufacture of machines which had
already established their value. The consequence is that a
variety of machines figure in the British aerial navy. Private
initiative is excellently seconded by the Government
manufacturing aeroplane factory, while the training of pilots
is likewise being carried out upon a comprehensive scale.
British manufacture may be divided into two broad classes--the
production of aeroplanes and of waterplanes respectively.
Although there is a diversity of types there is a conspicuous
homogeneity for the most part, as was evidenced by the British
raid carried out on February 11-12, when a fleet of 34 machines
raided the various German military centres established along the
coast of Flanders.

Considerable secrecy has been displayed by the British Government
concerning the types of machines that are being utilised,
although ample evidence exists from the producing activity of the
various establishments that all available types which have
demonstrated their reliability and efficiency are being turned to
useful purpose. The Avro and Sopwith warplanes with their very
high speeds have proved remarkably successful.

So far as manufacturing is concerned the Royal Aerial Factory may
be said to constitute the back bone of the British aerial fleet.
This factory fulfils various purposes. It is not only engaged in
the manufacture of machines, and the development of aeroplanes
for specific duties, but also carries out the inspection and
testing of machines built by private firms. Every machine is
submitted to an exacting test before it is passed into the
service.

Three broad types of Government machines are manufactured at this
establishment. There is that designed essentially for scouting
operations, in which speed is the all-important factor and which
is of the tractor type. Another is the "Reconnoitring" machine
known officially as the "R.E." to-day, but formerly as the "B.E"
(Bleriot-Experimental), a considerable number of which are in
commission.

This machine is also of the tractor type, carrying a pilot and an
observer, and has a maximum speed of 40-50 miles per hour. If
required it can further be fitted with an automatic gun for
defence and attack. The third craft is essentially a fighting
machine. Owing to the introduction of the machine-gun which is
fixed in the prow, with the marksman immediately behind it, the
screw is placed at the rear. The pilot has his seat behind the
gunner. The outstanding feature of these machines is the high
factor of safety, which attribute has astonished some of the
foremost aviation experts in the world.

Great Britain lagged behind her Continental rivals in the
development of the Fourth Arm, especially in matters pertaining
to motive power. For some time reliance was placed upon foreign
light highspeed explosion motors, but private enterprise was
encouraged, with the result that British Motors comparing
favourably in every respect with the best productions upon the
Continent are now available. Development is still proceeding,
and there is every evidence that in the near future entire
reliance will be placed upon the native motor.

Undoubtedly, as the war progresses, many valuable lessons will
be learned which will exercise an important bearing upon the
design and construction of warplanes. The ordeals to which the
machines are submitted in military duties are far more severe
than any imposed by the conditions of commerce. Accordingly
there is every indication that the conflict upon the Continent
will represent a distinctive epoch in aeroplane design and
construction. Many problems still await solution, such as the
capacity to hover over a position, and it is quite possible
that these complex and baffling questions will be settled
definitely as the result of operations in the field. The
aeroplane has reached a certain stage of evolution: further
progress is virtually impossible unless something revolutionary
is revealed, perfected, and brought to the practical stage.

CHAPTER VIII
SCOUTING FROM THE SKIES

From the moment when human flight was lifted from the rut of
experiment to the field of practical application, many theories,
interesting and illuminating, concerning the utility of the
Fourth Arm as a military unit were advanced. The general
consensus of expert opinion was that the flying machine would be
useful to glean information concerning the movements of an enemy,
rather than as a weapon of offence.

The war is substantiating this argument very completely.
Although bomb-dropping is practised somewhat extensively, the
results achieved are rather moral than material in their effects.
Here and there startling successes have been recorded especially
upon the British side, but these triumphs are outnumbered by the
failures in this direction, and merely serve to emphasise the
views of the theorists.

The argument was also advanced that, in this particular work, the
aeroplane would prove more valuable than the dirigible, but
actual campaigning has proved conclusively that the dirigible and
the heavier-than-air machines have their respective fields of
utility in the capacity of scouts. In fact in the very earliest
days of the war, the British airships, though small and slow in
movement, proved more serviceable for this duty than their
dynamic consorts. This result was probably due to the fact that
military strategy and tactics were somewhat nonplussed by the
appearance of this new factor. At the time it was an entirely
unknown quantity. It is true that aircraft had been employed in
the Balkan and the Italo-Ottoman campaigns, but upon such a
limited scale as to afford no comprehensive idea of their
military value and possibilities.

The belligerents, therefore, were caught somewhat at a
disadvantage, and an appreciable period of time elapsed before
the significance of the aerial force could be appreciated, while
means of counter acting or nullifying its influences had to be
evolved simultaneously, and according to the exigencies of the
moment. At all events, the protagonists were somewhat loth to
utilise the dirigible upon an elaborate scale or in an
aggressive manner. It was employed more after the fashion of a
captive balloon, being sent aloft from a point well behind the
front lines of the force to which it was attached, and well out
of the range of hostile guns. Its manoeuvres were somewhat
circumscribed, and were carried out at a safe distance from the
enemy, dependence being placed upon the advantages of an
elevated position for the gathering of information.

But as the campaign progressed, the airships became more daring.
Their ability to soar to a great height offered them complete
protection against gun-fire, and accordingly sallies over the
hostile lines were carried out. But even here a certain
hesitancy became manifest. This was perfectly excusable, for the
simple reason that the dirigible, above all, is a fair-weather
craft, and disasters, which had overtaken these vessels time
after time, rendered prudence imperative. Moreover, but little
was known of the range and destructiveness of anti-aircraft guns.

In the duty of reconnoitring the dirigible possesses one great
advantage over its heavier-than-air rival. It can remain
virtually stationary in the air, the propellers revolving at just
sufficient speed to off-set the wind and tendencies to drift. In
other words, it has the power of hovering over a position,
thereby enabling the observers to complete their task carefully
and with deliberation.

On the other hand, the means of enabling an aeroplane to hover
still remain to be discovered. It must travel at a certain speed
through the air to maintain its dynamic equilibrium, and this
speed is often too high to enable the airman to complete his
reconnaissance with sufficient accuracy to be of value to the
forces below. All that the aeroplane can do is to circle above a
certain position until the observer is satisfied with the data he
has collected.

But hovering on the part of the dirigible is not without
conspicuous drawbacks. The work of observation cannot be
conducted with any degree of accuracy at an excessive altitude.
Experience has proved that the range of the latest types of anti-
aircraft weapons is in excess of anticipations. The result is
that the airship is useless when hovering beyond the zone of
fire. The atmospheric haze, even in the clearest weather,
obstructs the observer's vision. The caprices of this obstacle
are extraordinary, as anyone who has indulged in ballooning
knows fully well. On a clear summer's day I have been able to
see the ground beneath with perfect distinctness from a height of
4,500 feet, yet when the craft had ascended a further two or
three hundred feet, the panorama was blurred. A film of haze
lies between the balloon and the ground beneath. And the
character of this haze is continually changing, so that the
aerial observer's task is rendered additionally difficult. Its
effects are particularly notice able when one attempts to
photograph the view unfolded below. Plate after plate may be
exposed and nothing will be revealed. Yet at a slightly lower
altitude the plates may be exposed and perfectly sharp and
well-defined images will be obtained.

Seeing that the photographic eye is keener and more searching
than the human organ of sight, it is obvious that this haze
constitutes a very formidable obstacle. German military
observers, who have accompanied the Zeppelins and Parsevals on
numerous aerial journeys under varying conditions of weather,
have repeatedly drawn attention to this factor and its caprices,
and have not hesitated to venture the opinion that it would
interfere seriously with military aerial reconnaissances, and
also that it would tend to render such work extremely hazardous
at times.

When these conditions prevail the dirigible must carry out its
work upon the broad lines of the aeroplane. It must descend to
the level where a clear view of the ground may be obtained, and
in the interests of safety it has to keep on the move. To
attempt to hover within 4,000 feet of the ground is to court
certain disaster, inasmuch as the vessel offers a magnificent and
steady target which the average gunner, equipped with the latest
sighting devices and the most recent types of guns, scarcely
could fail to hit.

But the airman in the aeroplane is able to descend to a
comparatively low level in safety. The speed and mobility of his
machine constitute his protection. He can vary his altitude,
perhaps only thirty or forty feet, with ease and rapidity, and
this erratic movement is more than sufficient to perplex the
marksmen below, although the airman is endangered if a rafale is
fired in such a manner as to cover a wide zone.

Although the aeroplane may travel rapidly it is not too fleet for
a keen observer who is skilled in his peculiar task. He may only
gather a rough idea of the disposition of troops, their
movements, the lines of communication, and other details which
are indispensable to his commander, but in the main the
intelligence will be fairly accurate. Undulating flight enables
him to determine speedily the altitude at which he is able to
obtain the clearest views of the country beneath. Moreover,
owing to his speed he is able to complete his task in far less
time than his colleague operating in the dirigible, the result
being that the information placed at the disposal of his superior
officers is more to the moment, and accordingly of greater value.

Reconnoitring by aeroplane may be divided into two broad
categories, which, though correlated to a certain degree, are
distinctive, because each constitutes a specific phase in
military operations. They are known respectively as "tactical"
and "strategical" movements. The first is somewhat limited in
its scope as compared with the latter, and has invariably to be
carried out rapidly, whereas the strategical reconnaissance may
occupy several hours.

The tactical reconnaissance concerns the corps or divisional
commander to which the warplane is attached, and consequently its
task is confined to the observation of the line immediately
facing the particular corps or division. The aviator does not
necessarily penetrate beyond the lines of the enemy, but, as a
rule limits his flight to some distance from his outermost
defences. The airman must possess a quick eye, because
his especial duty is to note the disposition of the troops
immediately facing him, the placing of the artillery, and any
local movements of the forces that may be in progress.
Consequently the aviator engaged on this service may be absent
from his lines for only a few minutes, comparatively speaking;
the intelligence he acquires must be speedily communicated to the
force to which he is attached, because it may influence a local
movement.

The strategical reconnaissance, on the other hand, affects the
whole plan of campaign. The aviators told off for this duty are
attached to the staff of the Commander-in-Chief, and the work has
to be carried out upon a far more comprehensive and elaborate
scale, while the airmen are called upon to penetrate well into
the hostile territory to a point thirty, forty, or more miles
beyond the outposts.

The procedure is to instruct the flier either to carry out his
observations of the territory generally, or to report at length
upon a specified stretch of country. In the latter event he may
fly to and fro over the area in question until he has acquired
all the data it is possible to collect. His work not only
comprises the general disposition of troops, defences, placing of
artillery, points where reserves are being held, high-roads,
railways, base camps, and so forth, but he is also instructed to
bring back as correct an idea as possible of what the enemy
proposes to do, so that his Commander-in-Chief may adjust his
moves accordingly. In order to perform this task with the
requisite degree of thoroughness it is often necessary for the
airman to remain in the air for several hours continuously, not
returning, in fact, until he has completed the allotted duty.

The airman engaged in strategical aerial reconnaissance must
possess, above all things, what is known as a "military" eye
concerning the country he traverses. He must form tolerably
correct estimates of the forces beneath and their character. He
must possess the ability to read a map rapidly as he moves
through the air and to note upon it all information which is
likely to be of service to the General Staff. The ability to
prepare military sketches rapidly and intelligibly is a valuable
attribute, and skill in aerial photography is a decidedly useful
acquisition.

Such men must be of considerable stamina, inasmuch as great
demands are made upon their powers of endurance. Being aloft for
several hours imposes a severe tax upon the nervous system, while
it must also be borne in mind that all sorts and conditions of
weather are likely to be encountered, more particularly during
the winter. Hail, rain, and blizzards may be experienced in
turn, while the extreme cold which often prevails in the higher
altitudes during the winter season is a fearful enemy to combat.
Often an airman upon his return from such a reconnaissance has
been discovered to be so numbed and dazed as a result of the
prolonged exposure, that considerable time has elapsed before he
has been sufficiently restored to set forth the results of his
observations in a coherent, intelligible manner for the benefit
of the General Staff. Under these circumstances it is not
surprising that the most skilful and experienced aviators are
generally reserved for this particular work. In addition to the
natural accidents to which the strategical aerial observer is
exposed, the dangers arising from hostile gun-fire must not be
overlooked. He is manoeuvring the whole time over the enemy's
firing zone, where anti-aircraft weapons are disposed
strategically, and where every effort is made by artillery to
bring him down, or compel him to repair to such a height as to
render observation with any degree of accuracy well-nigh
impossible.

The methods practised by the German aerial scout vary widely, and
are governed in no small measure by the intrepidity and skill of
the airman himself. One practice is to proceed alone upon long
flights over the enemy's lines, penetrating just as far into
hostile territory as the pilot considers advisable, and keeping,
of course, within the limits of the radius of action of the
machine, as represented by the fuel supply, the while carefully
taking mental stock of all that he observes below. It is a kind
of roving commission without any definite aim in view beyond the
collection of general intelligence.

This work, while productive and valuable to a certain degree, is
attended with grave danger, as the German airmen have repeatedly
found to their cost. Success is influenced very materially by
the accuracy of the airman's judgment. A slight miscalculation
of the velocity and direction of the wind, or failure to detect
any variations in the climatic conditions, is sufficient to prove
his undoing. German airmen who essayed journeys of discovery in
this manner, often failed to regain their lines because they
ventured too far, misjudged the speed of the wind which was
following them on the outward run, and ultimately were forced to
earth owing to the exhaustion of the fuel supply during the
homeward trip; the increased task imposed upon the motor, which
had to battle hard to make headway, caused the fuel consumption
per mile to exceed calculations.

Then the venturesome airman cannot neglect another factor which
is adverse to his success. Hostile airmen lie in wait, and a
fleet of aeroplanes is kept ready for instant service. They
permit the invader to penetrate well into their territory and
then ascend behind him to cut off his retreat. True, the invader
has the advantage of being on the wing, while the ether is wide
and deep, without any defined channels of communication. But
nine times out of ten the adventurous scout is trapped. His
chances of escape are slender, because his antagonists dispose
themselves strategically in the air. The invader outpaces one,
but in so doing comes within range of another. He is so harassed
that he either has to give fight, or, finding his retreat
hopelessly cut off, he makes a determined dash, trusting to his
high speed to carry him to safety. In these driving tactics the
French and British airmen have proved themselves adepts, more
particularly the latter, as the chase appeals to their sporting
instincts. There is nothing so exhilarating as a quarry who
displays a determination to run the gauntlet.

The roving Teuton scout was considerably in evidence in the early
days of the war, but two or three weeks' experience emphasised
the sad fact that, in aerial strategy, he was hopelessly
outmatched by his opponents. His advantage of speed was
nullified by the superior tactical and strategical acumen of his
antagonists, the result being that the German airman, who has
merely been trained along certain lines, who is in many cases
nothing more than a cog-wheel in a machine, and who is
proverbially slow-witted, has concluded that he is no match for
the airmen of the Allies. He found from bitter experience that
nothing afforded the Anglo-French military aviators such keen
delight as to lie in wait for a "rover," and then to swoop into
the air to round him up.

The proportion of these individual scouts who were either brought
down, or only just succeeded in reaching safety within their own
lines, and who were able to exhibit serious wounds as evidence of
the severity of the aerial tussle, or the narrowness of the
escape, has unnerved the Teuton airmen as a body to a very
considerable extent. Often, even when an aeroplane descended
within the German lines, it was found that the roving airman had
paid the penalty for his rashness with his life, so that his
journey had proved in vain, because all the intelligence he had
gained had died with him, or, if committed to paper, was so
unintelligible as to prove useless.

It was the success of the British airmen in this particular field
of duty which was responsible for the momentous declaration in
Field-Marshal Sir John French's famous despatch:--"The British
Flying Corps has succeeded in establishing an individual
ascendancy, which is as serviceable to us as it is damaging to
the enemy . . . . The enemy have been less enterprising in
their flights. Something in the direction of the mastery of the
air has already been gained."

The methods of the British airmen are in vivid contrast to the
practice of the venturesome Teuton aerial rovers described above.
While individual flights are undertaken they are not of unknown
duration or mileage. The man is given a definite duty to perform
and he ascends merely to fulfil it, returning with the
information at the earliest possible moment. It is aerial
scouting with a method. The intelligence is required and
obtained for a specific purpose, to govern a contemplated move in
the grim game of war.

Even then the flight is often undertaken by two or more airmen
for the purpose of checking and counterchecking information
gained, or to ensure such data being brought back to
headquarters, since it is quite possible that one of the party
may fall a victim to hostile fire. By operating upon these
lines there is very little likelihood of the mission proving
a complete failure. Even when raids upon certain places
such as Dusseldorf, Friedrichshafen or Cuxhaven are planned,
complete dependence is not placed on one individual. The machine
is accompanied, so that the possibility of the appointed task
being consummated is transformed almost into a certainty.

The French flying men work upon broadly similar lines. Their
fleet is divided into small squadrons each numbering four, six,
or more machines, according to the nature of the contemplated
task. Each airman is given an area of territory which is to be
reconnoitred thoroughly. In this way perhaps one hundred or more
miles of the enemy's front are searched for information at one
and the same time. The units of the squadron start out, each
taking the appointed direction according to the preconceived
plan, and each steering by the aid of compass and map. They are
urged to complete the work with all speed and to return to a
secret rendezvous.

Later the air is alive with the whirring of motors. The machines
are coming back and all converging to one point. They vol-plane
to the earth and gracefully settle down within a short distance
of each other at the rendezvous. The pilots collect and each
relates the intelligence he has gained. The data are collated
and in this manner the General Staff is able to learn exactly
what is transpiring over a long stretch of the hostile lines, and
a considerable distance to the rear of his advance works.
Possibly five hundred square miles have been reconnoitred in this
manner. Troops have been massed here, lines of communication
extend somewhere else, while convoys are moving at a third place.
But all has been observed, and the commanding officer is in a
position to re-arrange his forces accordingly. It is a
remarkable example of method in military tactics and strategy,
and conveys a striking idea of the degree to which aerial
operations have been organised.

After due deliberation it is decided that the convoys shall be
raided, or that massed troops shall be thrown into confusion, if
not dispersed. The squadron is ordered to prepare for another
aerial journey. The roads along which the convoys are moving are
indicated upon the map, or the position of the massed troops in
bivouac is similarly shown. The airmen load their machines with
a full charge of bombs. When all is ready the leader ascends,
followed in rapid succession by the other units, and they whirr
through the air in single file. It now becomes a grim game of
follow-my-leader.

The leader detects the convoy, swoops down, suddenly launches his
missiles, and re-ascends. He does not deviate a foot from his
path to observe the effects of his discharge, as the succeeding
aeroplane is close behind him. If the leader has missed then the
next airman may correct his error. One after another the
machines repeat the manoeuvre, in precisely the same manner as
the units of a battleship squadron emulate the leading vessel
when attacking the foe. The tactical evolutions have been laid
down, and there is rigid adherence thereto, because only thereby
may success be achieved. When the last war-plane has completed
its work, the leader swings round and repeats the dash upon the
foe. A hail of bullets may scream around the men in the air, but
one and all follow faithfully in the leader's trail. One or more
machines may fail in the attack, and may even meet with disaster,
but nothing interferes with the movements of the squadron as a
whole. It is the homogeneity of the attacking fleet which tells,
and which undermines the moral of the enemy, even if it does not
wreak decisive material devastation. The work accomplished to
the best of their ability, the airmen speed back to their lines
in the same formation.

At first sight reconnoitring from aloft may appear a simple
operation, but a little reflection will reveal the difficulties
and arduousness of the work. The observer, whether he be
specially deputed, or whether the work be placed in the hand of
the pilot himself--in this event the operation is rendered
additionally trying, as he also has to attend to his machine
must keep his eyes glued to the ground beneath and at the same
time be able to read the configuration of the panorama revealed
to him. He must also keep in touch with his map and compass, so
as to be positive of his position and direction. He must be a
first-class judge of distances and heights.

When flying rapidly at a height of 4,000 feet or more, the
country below appears as a perfect plane, or flat stretch,
although as a matter of fact it may be extremely undulating.
Consequently, it is by no means a simple matter to distinguish
eminences and depressions, or to determine the respective and
relative heights of hills.

If a rough sketch is required, the observer must be rapid in
thought, quick in determination, and facile with his pencil, as
the machine, no matter how it may be slowed down, is moving at a
relatively high speed. He must consult his map and compass
frequently, since an airman who loses his bearings is useless to
his commander-in-chief. He must have an eagle eye, so as to be
able to search the country unfolded below, in order to gather all
the information which is likely to be of value to his superior
officers. He must be able to judge accurately the numbers of
troops arrayed beneath him, the lines of the defensive works, to
distinguish the defended from the dummy lines which are thrown up
to baffle him, and to detect instantly the movement of the troops
and the direction, as well as the roads, along which they are
proceeding. Reserves and their complement, artillery,
railway-lines, roads, and bridges, if any, over streams and
railways must be noted--in short he must obtain an eye photograph
of the country he observes and grasp exactly what is happening
there. In winter, with the thermometer well down, a
blood-freezing wind blowing, wreaths of clouds drifting below and
obscuring vision for minutes at a time, the rain possibly pelting
down as if presaging a second deluge, the plight of the vigilant
human eye aloft is far from enviable.

Upon the return of the machine to its base, the report must be
prepared without delay. The picture recorded by the eye has to
be set down clearly and intelligibly with the utmost speed. The
requisite indications must be made accurately upon the map.
Nothing of importance must be omitted: the most trivial detail is
often of vital importance.

A facile pencil is of inestimable value in such operations.
While aloft the observer does not trust to his memory or his eye
picture, but commits the essential factors to paper in the form
of a code, or what may perhaps be described more accurately as a
shorthand pictorial interpretation of the things he has
witnessed. To the man in the street such a record would be
unintelligible, but it is pregnant with meaning, and when worked
out for the guidance of the superior officers is a mass of
invaluable detail.

At times it so happens that the airman has not been able to
complete his duty within the time anticipated by those below.
But he has gathered certain information which he wishes to
communicate without coming to earth. Such data may be dropped
from the clouds in the form of maps or messages. Although
wireless telegraphy is available for this purpose, it suffers
from certain drawbacks. If the enemy possesses an equipment
which is within range of that of the air-craft and the force to
which it belongs, communications may be nullified by the enemy
throwing out a continuous stream of useless signals which "jamb"
the intelligence of their opponents.

If a message--written in code--or a map is to be dropped from
aloft it is enclosed within a special metallic cylinder, fitted
with a vane tail to ensure direction of flight when launched, and
with a detonating head. This is dropped overboard. When it
strikes the ground the detonator fires a charge which emits a
report without damaging the message container, and at the same
time fires a combustible charge emitting considerable smoke. The
noise attracts anyone in the vicinity of the spot where the
message has fallen, while at the same time the clouds of smoke
guide one to the point and enable the cylinder to be recovered.
This device is extensively used by the German aviators, and has
proved highly serviceable; a similar contrivance is adopted by
French airmen.

There is one phase of aerial activity which remains to be
demonstrated. This is the utilisation of aerial craft by the
defenders of a besieged position such as a ring of fortifications
or fortified city. The utility of the Fourth Arm in this
province has been the subject of considerable speculation.
Expert opinion maintains that the advantage in this particular
connection would rest with the besiegers. The latter would be
able to ascertain the character of the defences and the defending
gun-force, by means of the aerial scout, who would prove of
inestimable value in directing the fire of the besieging forces.

On the other hand it is maintained that an aerial fleet would be
useless to the beleaguered. In the first place the latter would
experience grave difficulties in ascertaining the positions of
the attacking and fortress-reducing artillery, inasmuch as this
could be masked effectively, and it is thought that the aerial
force of the besieged would be speedily reduced to impotence,
since it would be subjected to an effective concentrated fire
from the ring of besieging anti-aircraft guns and other weapons.
In other words, the theory prevails that an aerial fleet, no
matter how efficient, would be rendered ineffective for the
simple reason that it would be the initial object of the
besieger's attack. Possibly the stem test of experience will
reveal the fallacy of these contentions as emphatically as it has
disproved others. But there is one point upon which authorities
are unanimous. If the artillery of the investing forces is
exposed and readily distinguishable, the aerial forces of the
beleaguered will bring about its speedy annihilation, as the
defensive artillery will be concentrated upon that of the
besiegers.

CHAPTER IX
THE AIRMAN AND ARTILLERY

There is one field in which the airman has achieved distinctive
triumphs. This is in the guidance of artillery fire. The modern
battle depends first and foremost upon the fierce effec tiveness
of big-gun assault, but to ensure this reliable direction is
imperative. No force has proved so invaluable for this purpose
as the man of-the-air, and consequently this is the province in
which he has been exceptionally and successfully active.

It will be recalled that in the Japanese investiture of Port
Arthur during the Russo-Japanese war, thousands of lives were
expended upon the retention and assault of 203 Metre Hill. It
was the most blood-stained spot upon the whole of the Eastern
Asiatic battlefield. General Nogi threw thousands after
thousands of his warriors against this rampart while the Russians
defended it no less resolutely. It was captured and re-captured;
in fact, the fighting round this eminence was so intense that it
appeared to the outsider to be more important to both sides than
even Port Arthur itself.

Yet if General Nogi had been in the possession of a single
aeroplane or dirigible it is safe to assert that scarcely one
hundred Japanese or Russian soldiers would have met their fate
upon this hill. Its value to the Japanese lay in one sole
factor. The Japanese heavy guns shelling the harbour and the
fleet it contained were posted upon the further side of this
eminence and the fire of these weapons was more or less
haphazard. No means of directing the artillery upon the vital
points were available; 203 Metre Hill interrupted the line of
sight. The Japanese thereupon resolved to capture the hill,
while the Russians, equally appreciative of the obstruction it
offered to their enemy, as valiantly strove to hold it. Once the
hill was captured and the fire of the Japanese guns could be
directed, the fate of the fortress was sealed.

Similar conditions have prevailed during the present campaign,
especially in the western theatre of war, where the ruggedness of
the country has tended to render artillery fire ineffective and
expensive unless efficiently controlled. When the German Army
attacked the line of the British forces so vehemently and
compelled the retreat at Mons, the devastating fire of the
enemy's artillery was directed almost exclusively by their
airmen, who hovered over the British lines, indicating exactly
the point where gun-fire could work the maximum of havoc. The
instant concentration of massed artillery fire upon the indicated
positions speedily rendered one position after another untenable.

The Germans maintained the upper hand until at last the aerial
forces of the British Expeditionary Army came into action. These
airmen attacked the Teuton aerial craft without the slightest
hesitation, and in a short while rendered cloudland absolutely
unhealthy. The sequel was interesting. As if suddenly blinded,
the German artillery fire immediately deteriorated. On the other
hand, the British artillery, now having the benefit of aerial
guidance, was able to repay the German onslaughts with interest,
and speedily compelled that elaborate digging-in of the infantry
lines which has now become so characteristic of the opposing
forces.

So far as the British lines are concerned the men in the trenches
keep a sharp look-out for hostile aeroplanes. The moment one is
observed to be advancing, all the men seclude themselves and
maintain their concealment. To do otherwise is to court a raking
artillery outburst. The German aeroplane, detecting the tendency
of the trenches describes in the air the location of the
vulnerable spot and the precise disposition by flying immediately
above the line. Twice the manoeuvre is repeated, the second
movement evidently being in the character of a check upon the
first observation, and in accordance with instructions, whereupon
the Tommies, to quote their own words, "know they are in for it!"
Ere the aeroplane has completed the second manoeuvre the German
guns ring out.

The facility with which artillery fire can be concentrated
through the medium of the aeroplane is amazing. In one instance,
according to the story related to me by an officer, "a number of
our men were resting in an open field immediately behind the
second line of trenches, being in fact the reserves intended for
the relief of the front lines during the following night. An
aeroplane hove in sight. The men dropped their kits and got
under cover in an adjacent wood. The aeroplane was flying at a
great height and evidently laboured under the impression that the
kits were men. Twice it flew over the field in the usual manner,
and then the storm of shrapnel, 'Jack Johnsons' and other tokens
from the Kaiser rained upon the confined space. A round four
hundred shells were dropped into that field in the short period
of ten minutes, and the range was so accurate that no single
shell fell outside the space. Had the men not hurried to cover
not one would have been left alive to tell the tale, because
every square foot of the land was searched through and through.
We laughed at the short-sightedness of the airman who had
contributed to such a waste of valuable shot and shell, but at
the same time appreciated the narrowness of our own escape."

The above instance is by no means isolated. It has happened time
after time. The slightest sign of activity in a trench when a
"Taube" is overhead suffices to cause the trench to be blown to
fragments, and time after time the British soldiers have had to
lie prone in their trenches and suffer partial burial as an
alternative to being riddled by shrapnel.

The method of ascertaining the range of the target from the
indications given by the aeroplane are of the simplest character.
The German method is for the aerial craft to fly over the
position, and when in vertical line therewith to discharge a
handful of tinsel, which, in falling, glitters in the sunlight,
or to launch a smoking missile which answers the same purpose as
a projectile provided with a tracer. This smoke-ball being
dropped over the position leaves a trail of black or whitish
smoke according to the climatic conditions which prevail, the
object being to enable the signal to be picked up with the
greatest facility. The height at which the aerial craft is
flying being known, a little triangulation upon the part of the
observer at the firing point enables him to calculate the range
and to have the guns laid accordingly.

When the aerial craft has been entrusted with the especial duty
of directing artillery-fire, a system of communication between
the aerial observer and the officer in charge of the artillery is
established, conducted, of course, by code. In the British Army,
signalling is both visual and audible. In daylight visual
signalling is carried out by means of coloured flags or streamers
and smoke-signals, while audible communication is effected by
means of a powerful horn working upon the siren principle and
similar to those used by automobiles. Both flags and
sound-signals, however, are restricted owing to the comparatively
short distances over which they can be read with any degree of
accuracy. The smoke-signal therefore appears to be the most
satisfactory and reliable, as the German airmen have proved
conclusively, for the simple reason that the trail of smoke may
be picked up with comparative ease, even at a distance, by means
of field glasses. The tinsel too, is readily distinguishable,
particularly in bright weather, for the glittering surface,
catching the sun-light, acts some what in the manner of a
heliograph.

The progress of the airman is followed by two officers at the
base from which he started. One is equipped with the director,
while the second takes the range. Directly this has been found
as a result of calculation, the guns are laid ready for firing.
In those cases where the enemy's artillery is concealed perhaps
behind a hill, the airman is of incalculable value, inasmuch as
he is able to reveal a position which otherwise would have to be
found by considerable haphazard firing, and which, even if
followed by a captive balloon anchored above the firing point,
might resist correction.

The accuracy of the airman's work in communicating the range has
been responsible for the high efficiency of the British and
French artillery. The latter, with the 75 millimetre
quick-firing gun, is particularly adapted to following up the
results of the aeroplane's reconnaissance, especially with the
system of rafale fire, because the whole position can be searched
through and through within a minute or two. According to
information which has been given to me by our artillery officers,
the British system also has proved disastrous to the enemy. The
practice is to get the range as communicated by the aeroplane, to
bring the artillery into position speedily, to discharge salvo
after salvo with all speed for a few minutes, and then to wheel
the artillery away before any hostile fire can be returned. The
celerity with which the British artillery comes into, and goes
out of, action has astonished even our own authorities. This
mobility is of unique value: it is taking advantage of a somewhat
slow-witted enemy with interest. By the time the Germans have
opened fire upon the point whence the British guns were
discharged, the latter have disappeared and are ready to let fly
from another point, some distance away, so that the hostile fire
is abortive. Mobility of such a character is decidedly unnerving
and baffling even to a quick-witted opponent.

In his search for hostile artillery the airman runs grave risks
and displays remarkable resource. It is invariably decided,
before he sets out, that he shall always return to a certain
altitude to communicate signals. Time after time the guns of the
enemy have been concealed so cunningly from aerial observation as
to pass unnoticed. This trait became more pronounced as the
campaigns of the Aisne progressed. Accordingly the airman adopts
a daring procedure. He swoops down over suspicious places, where
he thinks guns may be lurking, hoping that the enemy will betray
its presence. The ruse is invariably successful. The airman
makes a sudden dive towards the earth. The soldiers in hiding
below, who have become somewhat demoralised by the accuracy of
the British aerial bomb-throwers, have an attack of nerves. They
open a spirited fusillade in the hope of bringing the airman to
earth. But their very excitement contributes to his safety. The
shots are fired without careful aim and expend themselves
harmlessly. Sweeping once more upwards, the airman regains the
pre-determined level, performs a certain evolution in the air
which warns the observer at his base that he has made a
discovery, and promptly drops his guiding signal directly over
the point from which he has drawn fire.

Operations at night are conducted by means of coloured lights or
an electrical searchlight system. In the former instance three
lights are generally carried--white, red, and green--each of
which has a distinctive meaning. If reliance is placed upon the
electric light signalling lamp, then communications are in code.
But night operations are somewhat difficult and extremely
dangerous, except when the elements are propitious. There is the
ground mist which blots everything from sight, rendering
reconnaissance purely speculative. But on a clear night the
airman is more likely to prove successful. He keeps a vigilant
eye upon all ground-lights and by close observation is able to
determine their significance. It is for this reason that no
lights of any description are permitted in the advance trenches.
The striking of a match may easily betray a position to the alert
eye above.

So far as the British Army is concerned a complete code is in
operation for communicating between aeroplanes and the ground at
night. Very's lights are used for this purpose, it being
possible to distinguish the respective colours at a distance of
six miles and from an altitude of 2,000 feet. The lights are
used both by the aeroplane and the battery of artillery.

The code is varied frequently, but the following conveys a rough
idea of how communication is carried out by this means under
cover of darkness. The aeroplane has located its objective and
has returned to the pre-arranged altitude. A red light is thrown
by the airman. It indicates that he is directly over the enemy's
position. A similarly coloured light is shown by the artillery
officer, which intimates to the airman that his signal has been
observed and that the range has been taken.

In observing the effects of artillery fire a code of signals is
employed between the airman and the artillery officer to indicate
whether the shot is "long" or "short," to the right or to the
left of the mark, while others intimate whether the fuse is
correctly timed or otherwise. It is necessary to change the code
fairly frequently, not only lest it should fall into the enemy's
hands, but also to baffle the hostile forces; otherwise, after a
little experience, the latter would be able to divine the
significance of the signals, and, in anticipation of being
greeted with a warm fusillade, would complete hurried
arrangements to mitigate its effects, if not to vacate the
position until the bombardment had ceased.

Sufficient experience has already been gathered, however, to
prove the salient fact that the airman is destined to play an
important part in the direction and control of artillery-fire.
Already he has been responsible for a re-arrangement of strategy
and tactics. The man aloft holds such a superior position as to
defy subjugation; the alternative is to render his work more
difficult, if not absolutely impossible.

CHAPTER X
BOMB-THROWING FROM AIR-CRAFT

During the piping times of peace the utility of aircraft as
weapons of offence was discussed freely in an academic manner.
It was urged that the usefulness of such vessels in this
particular field would be restricted to bomb-throwing. So far
these contentions have been substantiated during the present
campaign. At the same time it was averred that even as a
bomb-thrower the ship of the air would prove an uncertain
quantity, and that the results achieved would be quite contrary
to expectations. Here again theory has been supported by
practice, inasmuch as the damage wrought by bombs has been
comparatively insignificant.

The Zeppelin raids upon Antwerp and Britain were a fiasco in the
military sense. The damage inflicted by the bombs was not at all
in proportion to the quantity of explosive used. True, in the
case of Antwerp, it demoralised the civilian population somewhat
effectively, which perhaps was the desired end, but the military
results were nil.

The Zeppelin, and indeed all dirigibles of large size, have one
advantage over aeroplanes. They are able to throw bombs of
larger size and charged with greater quantities of high explosive
and shrapnel than those which can be hurled from heavier-than-air
machines. Thus it has been stated that the largest Zeppelins can
drop single charges exceeding one ton in weight, but such a
statement is not to be credited.

The shell generally used by the Zeppelin measures about 47 inches
in length by 8 1/2 inches in diameter, and varies in weight from
200 to 242 pounds. Where destruction pure and simple is desired,
the shell is charged with a high explosive such as picric acid or
T.N.T., the colloquial abbreviation for the devastating agent
scientifically known as "Trinitrotoluene," the base of which, in
common with all the high explosives used by the different powers
and variously known as lyddite, melinite, cheddite, and so forth,
is picric acid. Such a bomb, if it strikes the objective, a
building, for instance, fairly and squarely, may inflict
widespread material damage.

On the other hand, where it is desired to scatter death, as well
as destruction, far and wide, an elaborate form of shrapnel shell
is utilised. The shell in addition to a bursting charge,
contains bullets, pieces of iron, and other metallic fragments.
When the shell bursts, their contents, together with the pieces
of the shell which is likewise broken up by the explosion, are
hurled in all directions over a radius of some 50 yards or more,
according to the bursting charge.

These shells are fired upon impact, a detonator exploding the
main charge. The detonator, comprising fulminate of mercury, is
placed in the head or tail of the missile. To secure perfect
detonation and to distribute the death-dealing contents evenly in
all directions, it is essential that the bomb should strike the
ground almost at right angles: otherwise the contents are hurled
irregularly and perhaps in one direction only. One great
objection to the percussion system, as the method of impact
detonation is called, is that the damage may be localised. A
bomb launched from a height of say 1,000 feet attains terrific
velocity, due to the force of gravity in conjunction with its own
weight, in consonance with the law concerning a falling body, by
the time it reaches the ground. It buries itself to a certain
depth before bursting so that the forces of the explosion become
somewhat muffled as it were. A huge deep hole--a miniature
volcano crater--is formed, while all the glass in the immediate
vicinity of the explosion may be shattered by the concussion, and
the walls of adjacent buildings be bespattered with shrapnel.

Although it is stated that an airship is able to drop a single
missile weighing one ton in weight, there has been no attempt to
prove the contention by practice. In all probability the
heaviest shell launched from a Zeppelin has not exceeded 300
pounds. There is one cogent reason for such a belief. A bomb
weighing one ton is equivalent to a similar weight of ballast.
If this were discarded suddenly the equilibrium of the dirigible
would be seriously disturbed--it would exert a tendency to fly
upwards at a rapid speed. It is doubtful whether the planes
controlling movement in the vertical plane would ever be able to
counteract this enormous vertical thrust. Something would have
to submit to the strain. Even if the dirigible displaced say 20
tons, and a bomb weighing one ton were discharged, the weight of
the balloon would be decreased suddenly by approximately five
per cent, so that it would shoot upwards at an alarming speed,
and some seconds would elapse before control was regained.

The method of launching bombs from airships varies considerably.
Some are released from a cradle, being tilted into position ready
for firing, while others are discharged from a tube somewhat
reminiscent of that used for firing torpedoes, with the exception
that little or no initial impetus is imparted to the missile; the
velocity it attains is essentially gravitational.

The French favour the tube-launching method since thereby it is
stated to be possible to take more accurate aim. The objective
is sighted and the bomb launched at the critical moment. In some
instances the French employ an automatic detonator which
corresponds in a certain measure to the time-fuse of a shrapnel
shell fired from a gun.

The bomb-thrower reads the altitude of his airship as indicated
by his barometer or other recording instrument, and by means of a
table at his command ascertains in a moment the time which will
elapse before the bomb strikes the ground. The automatic
detonator is set in motion and the bomb released to explode
approximately at the height to which it is set. When it bursts
the full force of the explosion is distributed downwards and
laterally. Owing to the difficulty of ensuring the explosion of
the bomb at the exact height desired, it is also made to explode
upon impact so as to make doubly sure of its efficacy.

Firing timed bombs from aloft, however, is not free from
excitement and danger, as the experience of a French airman
demonstrates. His dirigible had been commanded to make a
night-raid upon a railway station which was a strategical
junction for the movement of the enemy's troops. Although the
hostile searchlights were active, the airship contrived to slip
between the spokes of light without being observed. By
descending to a comparatively low altitude the pilot was able to
pick up the objective.

Three projectiles were discharged in rapid succession and then
the searchlights, being concentrated, struck the airship,
revealing its presence to the troops below. Instantly a spirited
fusillade broke out. The airmen, by throwing ballast and other
portable articles overboard pell-mell, rose rapidly, pursued by
the hostile shells.

In the upward travel the bomb-thrower decided to have a parting
shot. The airship was steadied momentarily to enable the range
to be taken, the automatic detonator was set going and the bomb
slipped into the launching tube. But for some reason or other
the missile jambed.

The situation was desperate. In a few seconds the bomb would
burst and shatter the airship. The bomb-thrower grabbed a tool
and climbing into the rigging below hacked away at the bomb-
throwing tube until the whole equipment was cut adrift and fell
clear of the vessel. Almost instantly there was a terrific
explosion in mid-air. The blast of air caused the vessel to roll
and pitch in a disconcerting manner, but as the airman permitted
the craft to continue its upward course unchecked, she soon
steadied herself and was brought under control once more.

The bomb carried by aeroplanes differs consider ably from that
used by dirigibles, is smaller and more convenient to handle,
though considering its weight and size it is remarkably
destructive. In this instance complete reliance is placed upon
detonation by impact. The latest types of British war-plane
bombs have been made particularly formidable, those employed in
the "raids in force" ranging up to 95 pounds in weight.

The type of bomb which has proved to be the most successful is
pear-shaped. The tail spindle is given an arrow-head shape, the
vanes being utilised to steady the downward flight of the
missile. In falling the bomb spins round, the rotating speed
increasing as the projectile gathers velocity. The vanes act as
a guide, keeping the projectile in as vertical a plane as
possible, and ensuring that the rounded head shall strike the
ground. The earlier types of bombs were not fitted with these
vanes, the result being that sometimes they turned over and over
as they fell through the air, while more often than not they
failed to explode upon striking the ground.

The method of launching the bomb also varies considerably,
experience not having indicated the most efficient method of
consummating this end. In some cases the bombs are carried in a
cradle placed beneath the aeroplane and launched merely by
tilting them in a kind of sling, one by one, to enable them to
drop to the ground, this action being controlled by means of a
lever. In another instance they are dropped over the side of the
car by the pilot, the tail of the bomb being fitted with a swivel
and ring to facilitate the operation. Some of the French
aviators favour a still simpler method. The bomb is attached to
a thread and lowered over the side. At the critical moment it is
released simply by severing the thread. Such aeroplane bombs,
however, constitute a menace to the machine and to the pilot.
Should the bomb be struck by hostile rifle or shell fire while
the machine is aloft, an explosion is probable; while should the
aero plane make an abrupt descent the missiles are likely to be
detonated.

A bomb which circumvents this menace and which in fact will
explode only when it strikes the ground is that devised by Mr.
Marten-Hale. This projectile follows the usual pear-shape, and
has a rotating tail to preserve direction when in flight. The
detonator is held away from the main charge by a collar and
ball-bearing which are held in place by the projecting end of a
screw-releasing spindle. When the bomb is dropped the rotating
tail causes the spindle to screw upwards until the projection
moves away from the steel balls, thereby allowing them to fall
inward when the collar and the detonator are released. In order
to bring about this action the bomb must have a fall of at least
200 feet.

When the bomb strikes the ground the detonator falls down on the
charge, fires the latter, and thus brings about the bursting of
the bomb. The projectile is of the shrapnel type. It weighs 20
pounds complete, is charged with some four pounds of T.N.T., and
carries 340 steel balls, which represent a weight of 5 3/4
pounds.

The firing mechanism is extremely sensitive and the bomb will
burst upon impact with the hull of an airship, water, or soft
soil. This projectile, when discharged, speedily assumes the
vertical position, so that there is every probability that it
will strike the ground fairly and squarely, although at the same
time such an impact is not imperative, because it will explode
even if the angle of incidence be only 5 degrees. It is
remarkably steady in its flight, the balancing and the design of
the tail frustrating completely any tendency to wobble or to turn
turtle while falling.

Other types of missile may be used. For instance, incendiary
bombs have been thrown with success in certain instances. These
bombs are similar in shape to the shrapnel projectile, but are
charged with petrol or some other equally highly inflammable
mixture, and fitted with a detonator. When they strike the
objective the bursting charge breaks up the shell, releasing the
contents, and simultaneously ignites the combustible.

Another shell is the smoke-bomb, which, up to the present, has
been used only upon a restricted scale. This missile is charged
with a certain quantity of explosive to burst the shell, and a
substance which, when ignited, emits copious clouds of dense
smoke. The scope of such a shell is somewhat restricted, it is
used only for the purpose of obstructing hostile artillery fire.
The shells are dropped in front of the artillery position and the
clouds of smoke which are emitted naturally inter fere with the
operations of the gunners. These bombs have also been used with
advantage to denote the position of concealed hostile artillery,
although their utility in this connection is somewhat uncertain,
owing to the difficulty of dropping the bomb so accurately as to
enable the range-finders to pick up the range.

Dropping bombs from aloft appears to be a very simple operation,
but as a matter of fact it is an extremely difficult matter to
strike the target, especially from a high altitude. So far as
the aeroplane is concerned it is somewhat at a disadvantage as
compared with the airship, as the latter is able to hover over a
position, and, if a spring-gun is employed to impart an initial
velocity to the missile, there is a greater probability of the
projectile striking the target provided it has been well-aimed.
But even then other conditions are likely to arise, such as
air-currents, which may swing the missile to one side of the
objective. Consequently adequate allowance has to be made for
windage, which is a very difficult factor to calculate from
aloft.

Bomb-dropping from an aeroplane is even more difficult. If for
instance the aeroplane is speeding along at 60 miles an hour, the
bomb when released will have a speed in the horizontal plane of
60 miles an hour, because momentarily it is travelling at the
speed of the aeroplane. Consequently the shell will describe a
curved trajectory, somewhat similar to that shown in Fig. 7.

On the other hand, if the aeroplane is travelling slowly, say at
20 miles an hour, the curve of the trajectory will be flatter,
and if a head wind be prevailing it may even be swept backwards
somewhat after it has lost its forward momentum, and describe a
trajectory similar to that in Fig. 8.

A bomb released from an altitude of 1000 feet seldom, if ever,
makes a bee-line for the earth, even if dropped from a stationary
airship. Accordingly, the airman has to release the bomb before
he reaches the target below. The determination of the critical
moment for the release is not easy, inasmuch as the airman has to
take into his calculations the speed of his machine, his
altitude, and the direction and velocity of the air-currents.

The difficulty of aiming has been demonstrated upon several
occasions at aviation meetings and other similar gatherings.
Monsieur Michelin, who has done so much for aviation in France,
offered a prize of L1,00--$5,000--in 1912 for bomb-dropping from
an aeroplane. The target was a rectangular space marked out upon
the ground, measuring 170 feet long by 40 feet broad, and the
missiles had to be dropped from a height of 2,400 feet. The
prize was won by the well-known American airman, Lieutenant Riley
E. Scott, formerly of the United States Army. He dropped his
bombs in groups of three. The first round fell clear of the
target, but eight of the remaining missiles fell within the area.

In the German competition which was held at Gotha in September of
the same year the results were somewhat disappointing. Two
targets were provided. The one represented a military bivouac
occupying a superficies of 330 square feet, and the other a
captive balloon resembling a Zeppelin. The prizes offered were
L500, L200, and L80--$2,500, $1,000 and $400--respectively, and
were awarded to those who made the greatest number of hits. The
conditions were by no means so onerous as those imposed in the
Michelin contest, inasmuch as the altitude limit was set at 660
feet, while no machine was to descend within 165 feet. The first
competitor completely failed to hit the balloon. The second
competitor flying at 800 feet landed seven bombs within the
square, but only one other competitor succeeded in placing one
bomb within the space.

Bomb-dropping under the above conditions, however, is vastly
dissimilar from such work under the grim realities of war. The
airman has to act quickly, take his enemy by surprise, avail
himself of any protective covering which may exist, and incur
great risks. The opposing forces are overwhelmingly against him.
The modern rifle, if fired vertically into the air, will hurl the
bullet to a height of about 5,000 feet, while the weapons which
have been designed to combat aircraft have a range of 10,000 feet
or more.

At the latter altitude aggressive tactics are useless. The
airman is unable to obtain a clear sharp view of the country
beneath owing to the interference offered to vision by
atmospheric haze, even in the dearest of weather. In order to
obtain reasonable accuracy of aim the corsair of the sky must fly
at about 400 feet. In this respect, however, the aeroplane is at
a decided advantage, as compared with the dirigible. The machine
offers a considerably smaller target and moves with much greater
speed. Experience of the war has shown that to attempt to hurl
bombs from an extreme height is merely a waste of ammunition.
True, they do a certain amount of damage, but this is due to
luck, not judgment.

For success in aerial bomb operations the human element is mainly
responsible. The daring airman is likely to achieve the greatest
results, as events have proved, especially when his raid is
sudden and takes the enemy by surprise. The raids carried out by
Marix, Collet, Briggs, Babington, Sippe and many others have
established this fact incontrovertibly. In all these operations
the airmen succeeded because of their intrepidity and their
decision to take advantage of cover, otherwise a prevailing mist
or low-lying clouds. Flight-Lieutenant Collet approached the
Zeppelin shed at Dusseldorf at an altitude of 6,000 feet. There
was a bank of mist below, which he encountered at 1,500 feet. He
traversed the depth of this layer and emerged therefrom at a
height of only 400 feet above the ground. His objective was
barely a quarter of a mile ahead. Travelling at high speed he
launched his bombs with what proved to be deadly precision, and
disappeared into cover almost before the enemy had grasped his
intentions. Lieutenant-Commander, now Flight-Commander, Marix
was even more daring. Apparently he had no mist in which to
conceal himself but trusted almost entirely to the speed of his
machine, which probably at times notched 90 miles per hour.
Although his advent was detected and he was greeted with a
spirited fusillade he clung to his determined idea. He headed
straight for the Zeppelin shed, launched two bombs and swung into
the higher reaches of the air without a moment's hesitation. His
aim was deadly, since both bombs found their mark, and the
Zeppelin docked within was blown up. The intrepid airman
experienced several narrow escapes, for his aeroplane was struck
twenty times, and one or two of the control wires were cut by
passing bullets.

The raid carried out by Commanders Briggs and Babington in
company with Lieutenant Sippe upon the Zeppelin workshops at
Friedrichshafen was even more daring. Leaving the Allies' lines
they ascended to an altitude of 4,500 feet, and at this height
held to the pre-arranged course until they encountered a mist,
which while protecting them from the alert eyes of the enemy
below, was responsible for the separation of the raiders, so that
each was forced to act independently and to trust to the compass
to bring him out of the ordeal successfully. Lieutenant Sippe
sighted Lake Constance, and taking advantage of the mist lying
low upon the water, descended to such an extent that he found
himself only a few feet above the roofs of the houses. Swinging
roundto the Lake he descended still lower until at last he was
practically skimming the surface of the Lake, since he flew at
the amazingly low height of barely seven feet off the water.
There is no doubt that the noise of his motor was heard plainly
by the enemy, but the mist completely enveloped him, and owing to
the strange pranks that fog plays with sound deceived his
antagonists.

At last, climbing above the bank of vapour, he found that he had
overshot the mark, so he turned quickly and sped backwards. At
the same time he discovered that he had been preceded by
Commander Briggs, who was bombarding the shed furiously, and who
himself was the object of a concentrated fire. Swooping down
once more, Lieutenant Sippe turned, rained his bombs upon the
objective beneath, drawing fire upon himself, but co-operating
with Commander Babington, who had now reached the scene, he
manoeuvred above the works and continued the bombardment until
their ammunition was expended, when they sped home-wards under
the cover of the mist. Considering the intensity of the hostile
fire, it is surprising that the aeroplanes were not smashed to
fragments. Undoubtedly the high speed of the machines and the
zigzagging courses which were followed nonplussed the enemy.
Commander Briggs was not so fortunate as his colleagues; a bullet
pierced his petrol tank, compelling a hurried descent.

The most amazing feature of these aerial raids has been the
remarkably low height at which the airmen have ventured to fly.
While such a procedure facilitates marksmanship it increases the
hazards. The airmen have to trust implicitly to the fleetness of
their craft and to their own nerve. Bearing in mind the
vulnerability of the average aeroplane, and the general absence
of protective armouring against rifle fire at almost point-blank
range, it shows the important part which the human element is
compelled to play in bomb-dropping operations.

Another missile which has been introduced by the French airmen,
and which is extremely deadly when hurled against dense masses of
men, is the steel arrow, or "flechette" as it is called. It is a
fiendish projectile consisting in reality of a pencil of solid
polished steel, 4 3/4 inches in length. The lower end has a
sharp tapering point, 5/8ths of an inch in length. For a
distance of 1 1/8th of an inch above this point the cylindrical
form of the pencil is preserved, but for the succeeding three
inches to the upper end, the pencil is provided with four equally
spaced angle flanges or vanes. This flanging of the upper end or
tail ensures the arrow spinning rapidly as it falls through the
air, and at the same times preserves its vertical position during
its descent. The weight of the arrow is two-thirds of an ounce.

The method of launching this fearsome projectile is ingenious. A
hundred or even more are packed in a vertical position in a
special receptacle, placed upon the floor of the aeroplane,
preferably near the foot of the pilot or observer. This
receptacle is fitted with a bottom moving in the manner of a
trap-door, and is opened by pressing a lever. The aviator has
merely to depress this pedal with his foot, when the box is
opened and the whole of the contents are released. The fall at
first is somewhat erratic, but this is an advantage, as it
enables the darts to scatter and to cover a wide area. As the
rotary motion of the arrows increases during the fall, the direct
line of flight becomes more pronounced until at last they assume
a vertical direction free from all wobbling, so that when they
alight upon the target they are quite plumb.

When launched from a height they strike the objective with
terrific force, and will readily penetrate a soldier's helmet and
skull. Indeed, when released at a height of 4,000 feet they have
been known to pierce a mounted soldier's head, and pass
vertically through his body and that of his horse also. Time
after time German soldiers have found themselves pinned to the
ground through the arrow striking and penetrating their feet.
Owing to the extremely light weight of the darts they can be
launched in batches of hundreds at a time, and in a promiscuous
manner when the objective is a massed body of infantry or
cavalry, or a transport convoy. They are extremely effective
when thrown among horses even from a comparatively low altitude,
not so much from the fatalities they produce, as from the fact
that they precipitate a stampede among the animals, which is
generally sufficiently serious and frantic to throw cavalry or a
transport-train into wild confusion.

Although aerial craft, when skilfully handled, have proved highly
successful as weapons of offence, the possibilities of such
aggression as yet are scarcely realised; aerial tactics are in
their infancy. Developments are moving rapidly. Great efforts
are being centred upon the evolution of more formidable missiles
to be launched from the clouds. The airman is destined to
inspire far greater awe than at present, to exercise a still more
demoralising influence, and to work infinitely more destruction.

CHAPTER XI
ARMOURED AEROPLANES

The stern test of war has served to reveal conclusively the fact
that aerial craft can be put out of action readily and
effectively, when once the marksman has picked up the range,
whether the gunner be conducting his operations with an anti-
aircraft gun stationed upon the ground, or from a hostile
machine. It will be remembered that Flight-Commander Briggs, on
the occasion of the daring British raid upon the Zeppelin sheds
at Friedrichshafen, was brought to the ground by a bullet which
penetrated his fuel tank. Several other vessels, British,
German, French, and Russian alike, have been thrown out of action
in a similar manner, and invariably the craft which has been
disabled suddenly in this way has fallen precipitately to earth
in the fatal headlong dive.

Previous to the outbreak of hostilities there was considerable
divergence of opinion upon this subject. The general opinion was
that the outspread wings and the stays which constituted the
weakest parts of the structure were most susceptible to gun-fire,
and thus were likely to fail. But practice has proved that it is
the driving mechanism which is the most vulnerable part of the
aeroplane.

This vulnerability of the essential feature of the flying machine
is a decisive weakness, and exposes the aviator to a constant
menace. It may be quite true that less than one bullet in a
thousand may hit the machine, but when the lucky missile does
find its billet its effect is complete. The fact must not be
overlooked that the gunners who work the batteries of
anti-aircraft guns are becommg more and more expert as a result
of practice, so that as time progresses and improved guns for
such duty are rendered available, the work of the aviator is
likely to become more dangerous and difficult. Experience has
proved that the high velocity gun of to-day is able to hurl its
projectile or shell to an extreme height--far greater than was
previously considered possible--so that considerable discretion
has to be exercised by the airman, who literally bears his life
in his hands.

Although elaborate trials were carried out upon the testing
ranges with the weapons devised especially for firing upon flying
machines, captive balloons being employed as targets, the data
thus obtained were neither conclusive nor illuminating. The
actual experiences of airmen have given us some very instructive
facts upon this point for the first time.

It was formerly held that the zone of fire that is to be
considered as a serious danger was within a height of about 4,500
feet. But this estimate was well within the mark. Airmen have
found that the modern projectiles devised for this phase of
operations are able to inflict distinctly serious damage at an
altitude of 9,000 feet. The shell itself may have but little of
its imparted velocity remaining at this altitude, but it must be
remembered that when the missile bursts, the contents thereof are
given an independent velocity, and a wide cone of dispersion,
which is quite sufficient to achieve the desired end, inasmuch as
the mechanism of the modern aeroplane and dirigible is somewhat
delicate.

It was for this reason that the possibility of armouring the
airship was discussed seriously, and many interesting experiments
in this field were carried out. At the same time it was decided
that the armouring should be effected upon lines analogous to
that prevailing in warship engineering. The craft should not
only be provided with defensive but also with aggressive
armament. This decision was not viewed with general approbation.
It was pointed out that questions of weight would arise,
especially in relation to the speed of the machine. Increased
weight, unless it were accompanied by a proportionate
augmentation of power in the motor, would react against the
efficiency and utility of the machine, would appreciably reduce
its speed, and would affect its climbing powers very adversely.
In some quarters it was maintained that as a result the machine
would even prove unsuited to military operations, inasmuch as
high speed is the primary factor in these.

Consequently it was decided by the foremost aviating experts that
machines would have to be classified and allotted to particular
spheres of work, just as warships are built in accordance with
the special duty which they are expected to perform. In
reconnaissance, speed is imperative, because such work in the air
coincides with that of the torpedo-boat or scout upon the seas.
It is designed to acquire information respecting the movements of
the enemy, so as to assist the heavier arms in the plan of
campaign. On the other hand, the fighting corsair of the skies
might be likened to the cruiser or battleship. It need not
possess such a high turn of speed, but must be equipped with
hard-hitting powers and be protected against attacking fire.

One attempt to secure the adequate protection against gun-fire
from the ground assumed the installation of bullet-proof steel
plating, about one fifth of an inch thick, below the tank and the
motor respectively. The disposition of the plating was such as
to offer the minimum of resistance to the air and yet to present
a plane surface to the ground below. So far as it went this
protection was completely effective, but it failed to armour the
vital parts against lateral, cross and downward fire while aloft.
As the latter is more to be feared than the fire from the ground,
seeing that it may be directed at point blank range, this was a
decided defect and the armour was subsequently abandoned as
useless.

The only effective method of achieving the desired end is to
armour the whole of the carriage or fuselage of the adroplane,
and this was the principle adopted by the Vickers Company. The
Vickers military aeroplane is essentially a military machine. It
is built of steel throughout. The skeleton of the machine is
formed of an alloy which combines the qualities of aluminium and
steel to ensure toughness, strength, and lightness. In fact,
metal is employed liberally throughout, except in connection with
the wings, which follow the usual lines of construction. The
body of the car is sheathed with steel plating which is bullet
proof against rifle or even shrapnel fire. The car is designed
to carry two persons; the seats are therefore disposed
tandemwise, with the observer or gunner occupying the front seat.

The defensive armament is adequate for ordinary purposes. Being
fitted with a 100 horse-power motor, fairly high speeds are
attainable, although the velocity is not equal to that of
machines constructed upon conventional lines, inasmuch as there
is an appreciable increase in weight.

The car is short and designed upon excellent stream lines, so
that the minimum of resistance to the air is offered, while at
the same time the balancing is perfect. The sides of the car are
brought up high enough to protect the aviators, only their heads
being visible when they are seated. The prow of the car follows
the lines generally adopted in high speed torpedo boat design;
there is a sharp knife edge stem with an enclosed fo'c's'le, the
latter housing the gun.

Another craft, designed for scouting operations, may be likened
to the mosquito craft of the seas. This machine, while a biplane
like the military aeroplane, is of lighter construction,
everything being sacrificed to speed in this instance. It is
fitted with a 100 horse-power motor and is designed to carry an
observer if required. There is no offensive armament, however.
The fuel tank capacity, moreover, is limited, being only
sufficient for a two or three hours' flight. While this is
adequate for general reconnoitring, which for the most part
entails short high speed flights, there are occasions when the
Staff demands more prolonged observations conducted over a
greater radius. This requisition can be met by eliminating the
observer, whose duties in this instance must be assumed by the
pilot, and substituting in place of the former, a second fuel
tank of sufficient capacity for a flight of four or five hours,
thereby bringing the term of action in the air to about 6 1/4
hours. This machine travels at a very high speed and is
eminently adapted to its specific duty, but it is of limited
service for general purposes.

The arming of an aeroplane, to enable it to defend itself against
hostile attack or to participate in raiding operations upon the
aerial fleet of the enemy, appears to be a simple task, but as a
matter of fact it is an undertaking beset with difficulties
innumerable. This is especially the case where the aeroplane is
of the tractive type, that is to say where the propellers are
placed in the forefront of the machine and in their revolution
serve to draw the machine forward. All other considerations must
necessarily be sacrificed to the mounting of the propeller.
Consequently it is by no means easy to allot a position for the
installation of a gun, or if such should be found there is grave
risk of the angle of fire being severely restricted. In fact, in
many instances the mounting of a gun is out of the question: it
becomes a greater menace to the machine than to the enemy.

The French aeronautical section of the military department
devoted considerable study to this subject, but found the problem
almost insurmount able. Monsieur Loiseau met with the greatest
measure of success, and his system is being practised in the
present campaign. This principle is essentially adapted to
tractor aeroplanes. Forward of the pilot a special position is
reserved for the gunner. A special mounting is provided towards
the prow, and upon the upper face of the body of the machine.
The gun mounting is disposed in such a manner that it is able to
command a wide arc of fire in the vertical plane over the nose of
the machine and more particularly in the downward direction.

The marksman is provided with a special seat, but when he comes
into action he has to stand to manipulate his weapon. The lower
part of his body is protected by a front shield of steel plate, a
fifth of an inch in thickness, while a light railing extending
upon either side and behind enables the gunner to maintain his
position when the aeroplane is banking and climbing. The machine
gun, of the Hotchkiss type, is mounted upon a swivel attached to
a tripod, while the latter is built into the bracing of the car,
so as to ensure a fairly steady gun platform.

While the gun in the hands of a trained marksman may be
manipulated with destructive effect, the drawbacks to the
arrangement are obvious. The gunner occupies a very exposed
position, and, although the bullet-proof shield serves to break
the effects of wind when travelling at high speed which renders
the sighting and training of the weapon extremely difficult, yet
he offers a conspicuous target, more particularly when the enemy
is able to assume the upper position in the air as a result of
superior speed in travelling. The gun, however, may be elevated
to about 60 degrees, which elevation may be accentuated by the
inclination of the aeroplane when climbing, while the facility
with which the weapon may be moved through the horizontal plane
is distinctly favourable.

But the aerial marksman suffers from one very pronounced defect:
he has a severely restricted survey of everything below, since
his vision is interrupted by the planes. The result is that an
enemy who has lost ascendancy of position is comparatively safe
if he is able to fly immediately below his adversary: the
mitrailleuse of the latter cannot be trained upon him. On the
other hand the enemy, if equipped with repeating rifles or
automatic pistols, is able to inflict appreciable damage upon the
craft overhead, the difficulties of firing vertically into the
air notwithstanding.

In the Vickers system, where the propeller is mounted behind the
car, the aeroplane thus operating upon the pusher principle, the
nose of the car is occupied by the arm, which is a rifle calibre
machine gun fitted upon a special mounting. The prow is provided
with an embrasure for the weapon and the latter is so installed
as to command an angle of 30 degrees on all sides of the
longitudinal axis of the machine when in flight. In this
instance the marksman is provided with complete protection on all
sides, inasmuch as his position is in the prow, where the hood of
the fo'c's'le shields him from overhead attack. The gun is
protected by a special shield which moves with the gun barrel.
This shield is provided with mica windows, through which the
gunner is able to sight his arm, so that he is not inconvenienced
in any way by the wind draught.

One shortcoming of such methods of arming an aeroplane will be
observed. Ahead firing only is possible; the weapon cannot be
trained astern, while similarly the line of fire on either
broadside is severely limited. This is one reason why the
machine-gun armament of aerial craft of the heavier-than-air type
has not undergone extensive development. In many instances the
pilot and observer have expressed their preference for repeating
high velocity rifles over any form of fixed gun mounting, and
have recourse to the latter only when the conditions are
extremely favourable to its effective employment.

Efforts are now being made to equip the military type of
aeroplane with both forward and astern firing guns. The urgency
of astern fire has been brought home very vividly. Suppose, for
instance, two hostile aeroplanes, A and B, are in the air. A has
the advantage at first, but B is speedier and rapidly overhauls
A. During the whole period of the overhauling movement the
gun of B can be directed upon A, while the latter, owing to the
arc of training being limited to c d cannot reply. Obviously in
the running fight it would be to the advantage of B, although the
fleeter machine, to keep behind A (position 1), but the latter is
making towards its own lines.

Under these circumstances A must be headed off, so B crowds on
speed to consummate this end. But in the overtaking process B
renders his gun-fire ineffective, inasmuch as B passes beyond the
arc of his gun which is represented by e f. But in so doing B
comes within the firing arc of A (position 9). To minimise this
danger B ascends to a higher level to obtain the paramount
position.

If, however, B were equipped with an astern gun the aeroplane A
would be within the fire of B when the forward gun of the latter
could not be used. Similarly if A were also fitted with an
astern gun it would be able to attack its pursuer the whole
time B was to its rear and in this event, if its gun-fire were
superior, it would be able to keep the latter to a safe distance,
or compel B to manoeuvre into a superior position, which would
entail a certain loss of time.

An astern firing gun would be valuable to B in another sense.
Directly it had passed A or brought the latter within the zone of
its astern gun it could maintain its fire at the most
advantageous range, because owing to its speed it would be able
to dictate the distance over which shots should be exchanged and
if mounted with a superior weapon would be able to keep beyond
the range of A's guns while at the same time it would keep A
within range of its own gun and consequently rake the latter. In
the interests of self-preservation A would be compelled to
change its course; in fact, B would be able to drive it in any
direction he desired, as he would command A's movements by
gun-fire.

The value of combined ahead and astern firing has been
appreciated, but there is one difficulty which at the moment
appears to be insuperable the clearance of the propeller. At the
moment astern-firing, if such it may be called, is maintained by
repeating rifles, but this armament is not to be compared with
machine-gun firing, as the latter with its capacity to pour 400
to 600 shots a minute, is far more deadly, particularly when the
weapon is manipulated by a crack gunner.

Up to the present the offensive armament of aeroplanes has been
confined to light machine guns such as the Hotchkiss, Berthier,
Schwartlose, and Maxim weapons. So far as the arming of
aeroplanes is concerned the indispensable condition is light
weight. With airships this factor is not so vital, the result
being that some dirigibles are mounted with guns, throwing one
pound bursting shells, fitted either with delay action or
percussion fuses, the former for preference. These shells are
given a wide cone of dispersion. Experiments are also being made
with a gun similar to the pom-pom which proved so useful in South
Africa, the gun throwing small shells varying from four to eight
ounces in weight at high velocity and in rapid succession. While
such missiles would not be likely to inflict appreciable damage
upon an armoured aeroplane, they would nevertheless be
disconcerting to the aviators subjected to such fire, and in
aerial combats the successful undermining of the adversary's
moral is of far greater importance than in land operations, since
immediately ascendancy in the artillery operations is attained
the final issue is a matter of moments.

But the most devastating arm which has yet been contrived for
aerial operations is the light machine gun which has recently
been perfected. The one objective with this weapon is to disable
the hostile aircraft's machinery. It fires an armour piercing
projectile which, striking the motor of any aircraft, would
instantly put the latter out of action. The shell has a diameter
of about .75 inch and weighs about four ounces. The gun is a
hybrid of the mitrailleuse and the French "Soixante-quinze,"
combining the firing rapidity of the former with the recoil
mechanism of the latter. This missile has established its
ability to penetrate the defensive armouring of any aeroplane and
the motor of the machine at 1,000 yards' range. This offensive
arm is now being manufactured, so that it is likely to be seen in
the near future as the main armament of aeroplanes.

At the moment widespread efforts are being made in the direction
of increasing the offensive efficiency of aircraft. It is one of
the phases of ingenuity which has been stimulated into activity
as a result of the war.

CHAPTER XII
BATTLES IN THE AIR

Ever since the days of Jules Verne no theme has proved so popular
in fiction as fighting in the air. It was a subject which lent
itself to vivid imagination and spirited picturesque portrayal.
Discussion might be provoked, but it inevitably proved abortive,
inasmuch as there was a complete absence of data based upon
actual experience. The novelist was without any theory: he
avowedly depended upon the brilliance of his imagination. The
critic could only theorise, and no matter how dogmatic his
reasonings, they were certainly as unconvincing as those of the
object of his attack.

But truth has proved stranger than fiction. The imaginative
pictures of the novelist have not only been fulfilled but
surpassed, while the theorising critic has been utterly
confounded. Fighting in the air has become so inseparable from
the military operations of to-day that it occurs with startling
frequency. A contest between hostile aeroplanes, hundreds of
feet above the earth, is no longer regarded as a dramatic,
thrilling spectacle: it has become as matter-of-fact as a bayonet
melee between opposed forces of infantry.

A duel in the clouds differs from any other form of encounter.
It is fought mercilessly: there can be no question of quarter or
surrender. The white flag is no protection, for the simple
reason that science and mechanical ingenuity have failed, so far,
to devise a means of taking an aeroplane in tow. The victor has
no possible method of forcing the vanquished to the ground in his
own territory except driving. If such a move be made there is
the risk that the latter will take the advantage of a critical
opportunity to effect his escape, or to turn the tables. For
these reasons the fight is fought to a conclusive finish.

To aspire to success in these combats waged in the trackless
blue, speed, initiative, and daring are essential. Success falls
to the swift in every instance. An aeroplane travelling at a
high speed, and pursuing an undulating or irregular trajectory is
almostimpossible to hit from the ground, as sighting is so
extremely difficult. Sighting from another machine, which
likewise is travelling rapidly, and pursuing an irregular path,
is far more so. Unless the attacker can approach relatively
closely to his enemy the possibility of hitting him is extremely
remote. Rifle or gun-fire must be absolutely point blank.

When a marauding aeroplane is espied the attacking corsair
immediately struggles for the strategical position, which is
above his adversary. To fire upwards from one aeroplane at
another is virtually impossible, at least with any degree of
accuracy. The marksman is at a hopeless disadvantage. If the
pilot be unaccompanied and entirely dependent upon his own
resources he cannot hope to fire vertically above him, for the
simple reason that in so doing he must relinquish control of his
machine. A rifle cannot possibly be sighted under such
conditions, inasmuch as it demands that the rifleman shall lean
back so as to obtain control of his weapon and to bring it to
bear upon his objective. Even if a long range Mauser or other
automatic pistol of the latest type be employed, two hands are
necessary for firing purposes, more particularly as, under such
conditions, the machine, if not kept under control, is apt to
lurch and pitch disconcertingly.

Even a colleague carried for the express purpose of aggression is
handicapped. If he has a machinegun, such as a Maxim or a
mitrailleuse, it is almost out of the question to train it
vertically. Its useful vertical training arc is probably limited
to about 80 degrees, and at this elevation the gunner has to
assume an extremely uncomfortable position, especiauy upon an
aeroplane, where, under the best of circumstances, he is somewhat
cramped.

On the other hand the man in the aeroplane above holds the
dominating position. He is immediately above his adversary and
firing may be carried out with facility. The conditions are
wholly in his favour. Sighting and firing downwards, even if
absolutely vertically, imposes the minimum physical effort, with
the result that the marksman is able to bring a steadier aim upon
his adversary. Even if the machine be carrying only the pilot,
the latter is able to fire upon his enemy without necessarily
releasing control of his motor, even for a moment.

If he is a skilled sharpshooter, and the exigencies demand, he
can level, sight, and fire his weapon with one hand, while under
such circumstances an automatic self-loading pistol can be
trained upon the objective with the greatest ease. If the
warplane be carrying a second person, acting as a gunner, the
latter can maintain an effective rifle fusillade, and, at the
same time, manipulate his machine-gun with no great effort,
maintaining rifle fire until the pilot, by manoeuvring, can
enable the mitrailleuse or Maxim to be used to the greatest
advantage.

Hence the wonderful display of tactical operations when two
hostile aeroplanes sight one another. The hunted at first
endeavours to learn the turn of speed which his antagonist
commands. If the latter is inferior, the pursued can either
profit from his advantage and race away to safety, or at once
begin to manoeuvre for position. If he is made of stern stuff,
he attempts the latter feat without delay. The pursuer, if he
realises that he is out classed in pace, divines that his quarry
will start climbing if he intends to show fight, so he begins to
climb also.

Now success in this tactical move will accrue to the machine
which possesses the finest climbing powers, and here again, of
course, speed is certain to count. But, on the other hand, the
prowess of the aviator--the human element once more--must not be
ignored. The war has demonstrated very convincingly that the
personal quality of the aviator often becomes the decisive
factor.

A spirited contest in the air is one of the grimmest and most
thrilling spectacles possible to conceive, and it displays the
skill of the aviator in a striking manner. Daring sweeps,
startling wheels, breathless vol-planes, and remarkable climbs
are carried out. One wonders how the machine can possibly
withstand the racking strains to which it is subjected. The
average aeroplane demands space in which to describe a turn, and
the wheel has to be manipulated carefully and dexterously, an
operation requiring considerable judgment on the part of the
helmsman.

But in an aerial duel discretion is flung to the winds. The
pilot jambs his helm over in his keen struggle to gain the
superior position, causing the machine to groan and almost to
heel over. The stem stresses of war have served to reveal the
perfection of the modern aeroplane together with the remarkable
strength of its construction. In one or two instances, when a

Book of the day: