aeroplanes and dirigibles of war-第4章
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devoted considerable attention to this subject; but from the
results which they have achieved up to the present this guiding
knowledge appears to be more spectacular and impressive than
effective。
To put a captive balloon out of action one must either riddle the
envelope; causing it to leak like a sieve; blow the vessel to
pieces; or ignite the highly inflammable gas with which it is
inflated。 Individual rifle fire will inflict no tangible damage。
A bullet; if it finds its billet; will merely pass through the
envelope and leave two small punctures。 True; these vents will
allow the gas to escape; but this action will proceed so slowly
as to permit the vessel to remain aloft long enough to enable the
observer to complete his work。 A lucky rifle volley; or the
stream of bullets from a machine gun may riddle the envelope;
precipitating a hurried descent; owing to the greater number of
perforations through which the gas is able to escape; but as a
rule the observer will be able to land safely。
Consequently the general practice is to shatter the aerostat; and
to this end either shrapnel; high explosive; or incendiary shells
will be used。 The former must explode quite close to the balloon
in order to achieve the desired end; while the incendiary shell
must actually strike it; so as to fire the gas。 The high
explosive shell may explode effectually some feet away from the
vessel; inasmuch as in this instance dependence is placed upon
the terrific concussion produced by the explosion which; acting
upon the fragile fabric of the balloon; brings about a complete
collapse of the envelope。 If a shrapnel is well placed and
explodes immediately above the balloon; the envelope will be torn
to shreds and a violent explosion of the gas will be precipitated。
But as a matter of fact; it is extremely difficult to place a
shrapnel shell so as to consummate this end。 The range is not
picked up easily; while the timing of the fuse to bring about the
explosion of the shell at the critical moment is invariably a
complex problem。
One favourite method of finding the range of a balloon is shown
in the accompanying diagrams。 The artillery battery is at B
and the captive balloon; C; is anchored at A。 On either
side of B and at a specified distance; observers O1 and O2
respectively are stationed。 First a shell is fired at 〃long〃
range; possibly the maximum range of the gun。 It bursts at D。
As it has burst immediately in the line of sight of B; but with
the smoke obscured by the figure of the balloon C; it is obvious
to B that the explosion has occurred behind the objective; but at
what distance he cannot tell。 To O1 and O2;however; it is seen
to have burst at a considerable distance behind C though to the
former it appears to have burst to the left and to the second
observer to the right of the target。
Another shell; at 〃short〃 range; is now fired; and it bursts at
E。 The explosion takes place in the line of sight of B; who
knows that he has fired short of the balloon because the latter
is eclipsed by the smoke。 But the two observers see that it is
very short; and here again the explosion appears to O1 to have
occurred to the right of the target; while to O2 it has evidently
burst to the left of the aerostat; as revealed by the relation of
the position of the balloon to the bursting of the shell shown in
Fig。 3。
A third round is fired; and the shell explodes at F。 In this
instance the explosion takes place below the balloon。 Both the
observers and the artillery man concur in their deductions upon
the point at which the shell burst。 But the shell must explode
above the balloon; and accordingly a fourth round is discharged
and the shell bursts at G。
This appears to be above the balloon; inasmuch as the lines of
sight of the two observers and B converge at this point。 But
whether the explosion occurs immediately above the vessel as is
desired; it is impossible to say definitely; because it may
explode too far behind to be effective。 Consequently; if this
shell should prove abortive; the practice is to decrease the
range gradually with each succeeding round until the explosion
occurs at the critical point; when; of course; the balloon is
destroyed。 An interesting idea of the difficulty of picking up
the range of a captive balloon may be gathered from the fact that
some ten minutes are required to complete the operation。
But success is due more to luck than judgment。 In the foregoing
explanation it is premised that the aerial vessel remains
stationary; which is an ex tremely unlikely contingency。 While
those upon the ground are striving to pick up the range; the
observer is equally active in his efforts to baffle his
opponents。 The observer follows each successive; round with keen
interest; and when the shells appear to be bursting at
uncomfortably close quarters naturally he intimates to his
colleagues below that he desires his position to be changed;
either by ascending to a higher point or descending。 In fact; he
may be content to come to the ground。 Nor must the fact be
overlooked that while the enemy is trying to place the observer
hors de combat; he is revealing the position of his artillery;
and the observer is equally industrious in picking up the range
of the hostile guns for the benefit of his friends below。
When the captive balloon is aloft in a wind the chances of the
enemy picking up the range thereof are extremely slender; as it
is continually swinging to and fro。 While there is always the
possibility of a shell bursting at such a lucky moment as to
demolish the aerial target; it is generally conceded to be
impossible to induce a shell to burst within 100 yards of a
balloon; no matter how skilfully the hostile battery may be
operated。
The value of the captive balloon has been demonstrated very
strikingly throughout the attack upon the entrenched German
positions in Flanders。 Owing to the undulating character of the
dunes the 〃spotters〃 upon the British monitors and battle ships
are unable to obtain a sweeping view of the country。 Accordingly
captive balloons are sent aloft in some cases from the deck of
the monitors; and in others from a suitable point upon the beach
itself。 The aerial observer from his point of vantage is able to
pick up the positions of the German forces and artillery with
ease and to communicate the data thus gained to the British
vessels; although subjected to heavy and continuous hostile fire。
The difficulty of hitting a captive balloon has been graphically
emphasised; inasmuch as the German artillerists have failed to
bring down a solitary balloon。 On the other hand the observer in
the air is able to signal the results of each salvo fired from
the British battleships as they manoeuvre at full speed up and
down the coastline; while he keeps the fire of the monitors
concentrated upon the German positions until the latter have been
rendered untenable or demolished。 The accuracy of the British
gun…fire has astonished even the Germans; but it has been
directly attributable to the rangefinder perched in the car of
the captive balloon and his rapid transmission of information to
the vessels below。
The enthusiastic supporters of aerial navigation maintained that
the dirigible and the aeroplane would supersede the captive
balloon completely。 But as a matter of fact the present conflict
has established the value of this factor more firmly than ever。
There is not the slightest possibility that the captive balloon
sections of the belligerents will be disbanded; especially those
which have the fruits of experience to guide them。 The airship
and the aeroplane have accomplished wonders; but despite their
achievements the captive balloon has fully substantiated its
value as a military unit in its particular field of operations。
CHAPTER III
GERMANY'S RISE TO MILITARY AIRSHIP SUPRE