PERILS OF THE AIR
There are people, very many people, who still regard flying as an
undertaking of an unreasonable peril, essayed mainly by those who are
in quest of money, notoriety, or sensation at any price. Such
people--still to be met with--have one mental picture, and one only,
of the flight of an aeroplane. They imagine a man in the air--and this
mere idea of altitude makes them shudder; and they picture this man in
a frail apparatus of wood and wire, capable of breaking to pieces at
any moment; or even if it does not break, needing an incessant
movement of levers to maintain it in a safe equilibrium; while they
reckon also that, should the engine of the machine suffer any
breakdown, the craft will drop to earth like a stone. Prejudice dies
hard; harder no doubt in England than in other countries. There are
still people, not few of them but many, who would be ready to declare,
offhand, that one aeroplane flight in six ends in a disaster.
It is a truism, but one that has a peculiar truth in aviation, to say
that history repeats itself. To-day we find large numbers of people
who still cherish the opinion that--save perhaps when on service in
war--it is nothing less than criminal foolishness for men to ascend in
aeroplanes. That attitude of mind persists; the growing safety of
flight has not affected it to any appreciable degree. But those eager
for the progress of aviation need not despair, or imagine that their
particular industry is being treated with any exceptional
disapprobation. They have only to look back a little in our history,
no great distance, and read of the receptions that were accorded the
first pioneers of our railways. Public meetings of protest have not
been held to condemn aviation; yet they were frequent in the days when
the first railways were projected. Vast indignation was indeed aroused;
it was declared to be against all reason, and a matter of appalling
risk, that people should be asked to travel from place to place in
such "engines of destruction." But the railways managed to survive
this storm. They were placed here and there about the country; they
were improved rapidly; and it would be hard, to-day, to find a safer
place than the compartment of a railway train.
Motor-cars, when their turn came, had to go through a similar ordeal.
There was the same indignation, the same chorus of protest; and when
the first of the pioneers, greatly daring, began actually to drive
their cars on the public highway, there were people who believed, and
who declared forcibly, that to permit such machines on our roads was
the crime of the century. Had not these pioneers struggled valiantly,
sparing neither time nor money, it is possible that the motor-car
might have been driven from the highway. But here again progress,
though it was retarded, could not be checked. The motor-car triumphed.
It grew rapidly more reliable, more silent, more pleasing to the eye;
and to-day it glides in thousands along our roads, a pleasure to those
who occupy it, a nuisance neither to pedestrians nor to other wheeled
traffic; more under control when it is well driven, and more ready to
stop quickly when required, than any horsed vehicle which it may have
replaced. At one time the papers were full of such headlines as:
"Another Motor-car Accident." Each small mishap received prominent
attention: and to the majority of people it seemed the wildest folly
to travel in such vehicles. Yet to-day--such is progress--these same
people ride in a motor-car, or a motor-cab, quite as a matter of
course and without a thought of risk.
When one discusses flying and its dangers, it is essential to maintain
an accurate sense of proportion. In the very earliest days, for
instance, it must be realised that the few men who then flew--they
could be numbered on the fingers of one hand--exercised the greatest
caution. They did not fly in high winds; they treated the air,
realising its unknown perils, with a very great and a very commendable
respect. Thus it was that thousands of miles were flown, even with the
crudest of these early machines, and with motors that were constantly
giving trouble, without serious accident. But after this, and very
quickly, the number of airmen grew. New aviators appeared every day;
contests were organised extensively; there were large sums of money to
be won, provided that one pilot could excel another. And the spirit of
caution was abandoned. Even while they were still using purely
experimental machines--craft of which neither the stability nor the
structural strength had been tested adequately--there grew a tendency
among airmen to fly in higher winds, to subject their machines to
greater strains, and to attempt dangerous manoeuvres so as to please
the crowds who paid to see them fly.
It was not surprising, therefore, that flying entered upon an era of
accidents. Such disasters were inevitable--inevitable, that is to say,
in view of the tendencies that then prevailed; though it is a
melancholy reflection that, had men been content to go ahead with the
same slow sureness of the pioneers, many of those lives which were
lost could have been saved.
To the public, not aware exactly of all that was going on, it appeared
as though the navigation of the air, instead of growing safer, was
becoming more dangerous. There were suggestions, indeed, made quite
seriously and in good faith, that these endeavours to fly should cease;
that the law should step in, and prevent any more men from risking
their lives. What people failed to realise, when they adopted this
view, was that instead of one or two men flying there were now
hundreds who navigated the air; that flights in large numbers were
being made daily; that thousands of miles instead of hundreds were
being traversed by air--and often under conditions the pioneers would
have considered far too dangerous. These facts, had they been realised,
would have shown people what was actually the true state of affairs;
that, though accidents seemed numerous, and were indeed more frequent
than they had been in the earliest days of flying, they were as a
matter of proportion, reckoning the greater number of men who were
flying, and the thousands of miles which were flown, growing steadily
less frequent.
There was this important fact to be reckoned with also. Each accident
that happened taught its lesson, and so made for future safety. A
considerable number of those early accidents can, for instance, be
traced to some structural weakness in a machine. The need in an
aircraft then, as now, was lightness; and in those days designers and
builders, owing purely to their inexperience, had not learned the art,
as they have to-day, of combining lightness with strength. So it was
that, as more powerful motors began to be fitted to aeroplanes, and
greater speeds were attained, it happened sometimes, when a machine
was being driven fast through a wind, that a plane would collapse, and
send the machine crashing to the ground; or in making a dive, perhaps,
either of necessity or to show his skill, a pilot would subject his
machine to such a strain that some part of it would break.
From such disasters as a rule, greatly to be regretted though they
were, the industry emerged so much the wiser. The strength of machines
was increased; the engines which drove them were rendered more
reliable; and gradually too, though none too rapidly, the airmen who
piloted them grew in knowledge and skill. But all this time, while
flying was being made more safe, there were accidents frequently for
the papers to report; and this was due entirely to the fact that there
were now thousands of men flying, where previously there had been
fifties and hundreds. The public could not realise how rapidly the
number of airmen had grown; that practically every day, at aerodromes
scattered over Europe, flights were so frequent that they were
becoming a commonplace. It was in 1912, as one of its many services to
aviation that the Aero Club of France was able to show, by means of
statistics which could not be questioned, that for every fatality
which had occurred in France, during that particular year, a distance
of nearly 100,000 miles had been flown in safety.
The cause of many of the early accidents was, as we have suggested,
the breakage of some part of a machine while in flight. In an analysis
for instance of thirty-two such disasters, it was shown that fourteen
were due to the collapse of sustaining planes, control-surfaces, or
some other vital part of a machine. And this risk of breakage in the
air was increased, in many cases, by the building of experimental
machines by men who had no qualifications for their task, and who
erred only too frequently, in their desire to attain lightness, on the
side of a lack, rather than an excess, of structural strength.
There are many cases, unfortunately, that might be cited; but one may
be sufficient here. A man with an idea for a light type of biplane, a
machine designed mainly for speed, had an experimental craft
built--this was in the pioneer days of 1909--and insisted on fitting
to it a motor of considerable power. It was pointed out to him that
his construction was not sufficiently strong, in view of the speed at
which his machine would pass through the air. But he was of the quiet,
determined, self-opinionated type, who pursued his own way and said
little. He did not strengthen his constructional, and he began a
series of flying tests. In the first of these, which were short, the
planes stood up to their work, and the fears of the critics seemed
groundless. But a day came when, venturing to some height, the aviator
encountered a strong and gusty wind; whereupon one of his main-planes
broke, and he fell to his death.
As a contrast to this tragedy, and a welcome one, there is a humorous
story, that is true, told of one experimenter. His knowledge of
construction was small, but what he lacked in this respect he made up
for in confidence; and he built a monoplane. This was in the days just
after the cross-Channel flight, and experimenters all over the world
were building monoplanes, some of them machines of the weirdest
description. The craft built by this enthusiast seemed all right in
its appearance; nothing had been spared, for instance, in the way of
varnish. When wheeled into the sun, for its first rolling test under
power, it looked an imposing piece of work. Friends were in attendance,
photographers also; and the would-be aviator was in faultless flying
gear. Mounting a ladder, which had been placed beside the machine, he
allowed his weight to bear upon the fusilage, and proceeded to settle
himself in his seat. But he, and the onlookers, were startled as he
did so by an ominous cracking of wood. It grew louder; something
serious and very unexpected was happening to the machine. As a matter
of fact, and just as it stood there without having moved a yard, the
whole of the flimsy structure parted in the middle, and the machine
settled down ignominiously upon the ground, its back broken, and with
the discomfited inventor struggling in the _debris_.
It was far from easy, in the early days, for even an expert
constructor to calculate the strains encountered under various
conditions of flight. In wind pressure, under certain states of the
air, there are dangerous fluctuations--fluctuations which, even with
the knowledge we possess to-day, and this is far from meagre, exhibit
phenomena concerning which much more information is required. Machines
have collapsed suddenly, while flying on a day when the wind has been
uncertain, and have done so in a way which has suggested that they had
encountered, suddenly, a gust of an altogether abnormal strength.
Occasionally, though research work in this field is extremely
difficult, it has been possible to gain data as to the existence of
conditions, prevalent as a rule over a small area, which would spell
grave risk for any aeroplane which encountered them. There is a
strange case, verified beyond question, which occurred during some
tests with man-lifting kites at Farnborough. These kites are strongly
built, and withstand as a rule extremely high winds. On this
particular day a kite, when it had reached a certain altitude, was
seen to crumple up suddenly. The wind did not seem specially
strong--not at any rate on the ground; and there appeared no reason
for the breakage of the kite. Another was sent up; but the same thing
happened, and at the same altitude. Then the officer who was in charge
of the kites sent for a superior. A third kite was flown to see what
would happen. This one broke exactly as the others had done, and at
just the same height--about five hundred feet. Precise data could not
be gained as to this phenomenon; but the breaking of these
kites--which had withstood extremely high pressure in previous
tests--was reckoned to be due to the fact that, when they reached a
certain point in the air, they were subjected to the violent strain of
a sudden and complete change in the direction of the wind. To the
pilot of an aeroplane, entering without warning some such area of
danger, the result might naturally be serious in the extreme.
The air has been, and is still, an uncharted sea. It does not flow
with uniformity over the surface of the earth. It is a constantly
disturbed element, and one that has the disadvantage of being
invisible. An aviator cannot see the dangerous currents and eddies
into which he may be steering his craft; and so it was not surprising,
in those days when aircraft were frailer than they should have been,
and cross-country flights were first being made, that machines broke
often while in flight and that the airman's enemy, the wind, claimed
many victims.
Wind fluctuations that are dangerous, those which possess for one
reason or another an abnormal strength, are encountered frequently
when a pilot is fairly near the earth; and his peril is all the
greater in consequence. On a windy day, one on which there are heavy
gusts followed by comparative lulls, it is when he is close to the
ground, either in ascending or before alighting, that a pilot has most
to fear. If he is well aloft, with plenty of air space beneath him,
and particularly if he has a machine that is inherently stable, he has
little to fear from the wind; save, perhaps, should his engine fail
him, or should he find--as has been the case in war flying--that the
force of the wind, blowing heavily against him, and reducing the speed
of his machine, has prevented him from regaining his own lines before
his petrol has become exhausted. The modern aeroplane, when its
engine-power is ample, and it is at a suitable altitude, can wage
battle successfully even with a gale. But it must rise from the earth
when it begins a flight, and return to earth again when its journey is
done; and here, in the areas of wind that are disturbed by hills,
woods, and contours of the land, there are often grave dangers. The
wind at these low altitudes blows flukily. Its direction may be
affected, for instance, owing to the influence of a hill or ridge. A
side gust, blowing powerfully and unexpectedly against a machine, just
as it is nearing the ground before alighting, may cause it to tilt to
such an angle that it begins a side-slip. If the craft was
sufficiently high in the air, when this happened, the pilot would be
able, probably, to convert the side-slip into a dive, and the dive
into a renewal of his normal flight. But if such a side-slip begins
near the ground, and there is an insufficient amount of clear space
below the machine, it may strike the ground in its fall, and become a
wreck, before there is time for the pilot, or for the machine itself,
to exercise a righting influence. The fact that a craft may be forced
temporarily from its equilibrium, say by a side-slip, is known now to
represent no great risk for the airman, granted always that he has the
advantage of altitude. The machine, in such circumstances, falls a
certain distance. This is inevitable, and for the reason that it must
regain forward speed--which it has lost temporarily in its
side-slip--before its own inherent stability can become effective, or
its pilot regain influence over his controls. And it is this
unavoidable descent, this short period during which the machine is
recovering its momentum, and during which the pilot has no power of
control, that represents in a heavy wind the moments of peril, should
a pilot enter an area of disturbance just as he nears the ground.
An aeroplane, when it sets out to fly in bad weather, may be likened
to a boat that is being launched from a beach upon a rough and stormy
sea. It is the waves close inshore, which may raise his craft only to
dash it to destruction, that the boatman has chiefly to fear; and for
the aviator, when he leaves the land and embarks upon the aerial sea,
or when he returns again from this element and must make his contact
with the earth, there lurks a risk that, caught suddenly by an air
wave, and with insufficient space beneath his machine, he may be
forced into a damaging impact with the ground. But the skill of
designers and constructors, to say nothing of the growing experience
of aviators, is working constantly towards a greater safety.
Of the risk attached to engine failure, when he is piloting a craft
fitted with only one motor, an airman is reminded frequently, not only
from his own experience, but from that of other flyers. With the
aeroplane engine, even with types that have gained a high average of
reliability, there are many possibilities of a slight mishap--each of
them sufficient, for the moment, to put an engine out of action--that
the pilot who is flying across country must, all the time he is in the
air, have at the back of his mind the thought that at any moment, and
perhaps without any warning, he may find that his motive power has
gone. A magneto may fail temporarily; an ignition wire or a valve
spring break. The aeroplane engine of to-day is, of course, an
infinitely more reliable piece of apparatus than it was in those early
days when Henry Farman, working with extraordinary patience at
Issy-les-Moulineaux, was endeavouring--and for a long time without
success--to make the motor in his Voisin biplane run for five
consecutive minutes without breakdown. The war has shown us, and under
working conditions which have been exceptionally trying, how reliable
the aero-motor has become. But until duplicate plants have been
perfected, and more than one motor is fitted to aircraft as a matter
of course, there must always be this risk of failure.
In the mere stoppage of a motor no great danger is implied. The pilot
must descend; that is all. His power gone, he must glide earthward.
But where the risk does lie, in engine failure, is that it may occur
at a moment when the airman is in such a position, either above
dangerous country or while over the sea, that he cannot during his
glide reach a place of safety. A study of flying will show how awkward,
and how perilous on many occasions, has been the stoppage of a motor
while a machine is in the air. Two historic instances, though they did
not, fortunately, end in a loss of the pilot's life, were the
compulsory descents into the Channel made by the late Mr. Hubert
Latham, during his attempts, in 1909, to fly from Calais to Dover. In
both these cases--once when only a few miles from the French shore,
and on the second occasion when the aeroplane was quite near its
destination--the motor of the Antoinette monoplane failed suddenly,
and the aviator could do nothing but plane down into the water. On the
first occasion he alighted neatly, suffering no injury, and being
rescued by a torpedo boat; but in the second descent, striking the
water hard, he was thrown forward in his seat and his head injured by
a strut.
Less fortunate, in a case of presumed engine failure that will become
historic, was Mr. Gustave Hamel. Eager to reach Hendon, so as to take
part in the Aerial Derby on May 23rd, 1914, his great experience of
Channel flying induced him to risk the crossing with a motor which, on
his flight from Paris to the coast, had not been running well. His
monoplane was a fast machine, and the flight across Channel would have
taken him less than half an hour. But at some point during the
crossing, it seems obvious, his engine failed him, and he was unable
to prolong his glide either to gain the shore, or the vicinity of a
passing ship. His monoplane was never recovered; but the body of the
aviator--whose loss was mourned throughout the flying world and by the
general public as well--was discovered by some fishermen while
cruising off the French coast, and identified by means of a map,
clothing, and an inflated motor-cycle tyre; the last-named being
carried by the airman round his body to act as an improvised life-belt.
Engine failure, though a fruitful cause of minor accidents, and of the
breakage of machines, has led to few fatalities; and this has been due
very largely to the fact that, though machines have descended under
dangerous circumstances, and have been wrecked in a manner that would
appear almost certain to kill their occupants, the pilots and
passengers have, as a matter of fact, escaped often with no more than
a shock or bruises. An aeroplane does not strike the ground with the
impact of a hard, unyielding structure. It is essentially frail in its
construction; and this frailness, though it spells destruction for the
machine in a bad descent, provides at the same time an element of
safety for its crew. Take the case for instance of a machine falling
sideways, and striking the ground with one plane or planes. These
planes, built of nothing stronger as a rule than wood, crumple under
the impact. But in their collapse, which is telescopic and to a
certain extent gradual, a large part of the shock is absorbed. By the
time the fusilage which contains the pilot touches ground, the full
force of the impact is gone. And it is the same, often, if a machine
makes a bad landing, say on awkward ground, and strikes heavily
bow-first. Granted that the occupants of the machine are well-placed,
and prevented by retaining belts from being flung from the machine,
they should escape injury from the fact that there is so much to be
broken, in the way of landing-gear and other parts, before the shock
of the impact can reach them in their seats.
Had it not been for the capacity of the aeroplane to alight in awkward
places without injury to its pilot, many lives might have been lost
through descents in which motors have failed. Aviators have been
obliged to land in most unsuitable places: on the roofs of houses, for
instance, in small gardens, and frequently on the tops of trees. If he
finds his engine fail him when he is over a wood or forest, and there
is no chance save to descend upon the trees, a skilled pilot may save
himself as a rule from injury. Planing down, till he is just above the
tree-tops, he will then check suddenly, by a movement of his elevator,
the forward speed of his machine. The craft will come to a standstill
in the air; then, the support gone from its planes owing to the loss
of forward speed, it will sink down almost vertically, and with very
little violence, on to the tops of the trees. The machine itself will
naturally be damaged, seeing that boughs will pierce its wings in many
places, and that one or more of its planes may possibly collapse. But
the net result of such a landing--and this is the point which is
important for the pilot--is that the machine will be caught up and
suspended on the trees, making a comparatively light and gradual
contact, instead of there being any risk of its driving through the
trees and making a heavy impact with the ground.
Humour, sometimes, may be extracted from such a predicament as engine
failure, though it needs an aviator with a very deeply ingrained sense
of humour to do so. The story is told, however, of a pilot who, flying
across difficult country with a passenger, found that his motor
failed--as they often will--just at a moment when there seemed no
possible landing-point below. Looking over the side of his machine,
and glancing quickly here and there, the aviator saw no alternative
but to bring his craft down in an orchard that lay below. Pointing
downward, to acquaint his passenger with their unpleasant situation,
and to call his attention also to the orchard, the pilot said with a
smile:
"I hope you're fond of apples!"
There is a risk in engine failure which has been emphasised more than
once; and it is that which may attend the pilot who, while prolonging
a glide in order to reach some landing-point, may be struck by a gust,
or enter some area of disturbed wind, just before he reaches the
ground and while his machine, moving slowly, is not in a position to
respond effectually to its controls. In one case an aviator,
struggling back towards the aerodrome with a motor which was not
giving its power, found that it stopped suddenly when he was not far
from a wood. Beyond the wood, which stood on a ridge, there was a
stretch of grassland. Endeavouring to reach this promised
landing-point, and holding his machine on a long glide, the airman
came across above the trees. He had almost reached his goal when his
machine entered a sudden down-current of wind--occasioned, no doubt,
by the proximity of the trees and ridge. Caught by this eddy, with no
motive power to help him and very little speed on his machine, the
pilot could not check its sudden dive; and the craft struck ground so
heavily that both he and his passenger were killed.
We have mentioned previously, as a fruitful cause of accident, that
structural weakness of machines which has led, when conditions have
been unfavourable, to a sudden collapse in the air. But apart from
weakness in construction, and notably in accidents with early-type
machines, there was the risk attached to mistakes in design, which
produced machines which were unstable under certain conditions--and
the dangers also which were due to inefficient controlling surfaces.
It was no uncommon thing, in pioneer days, for a machine to be built
which would not respond adequately to its elevator or rudder; though
this unpleasant fact might not be discovered by the pilot until he was
actually in flight, and perhaps at some distance from the earth. In
one case, which is authenticated, a two-seated monoplane of a new type
was tested at first in a series of straight flights, and found to be
promising in its behaviour. A skilled pilot then took charge of it,
and, carrying a passenger, proceeded to some more ambitious flights.
Steering the machine away across the aerodrome, and flying at a low
elevation, he approached a belt of woods. The machine was too near the
ground to pass over the tops of the trees; so the aviator decided to
make a turn, and fly parallel with the wood. But when he put his
rudder over, so as to bring the machine round in a half-circle, he
found to his dismay that there was no response. In the design of the
machine, as it was found afterwards, the rudder had been made too
small: it would not steer the machine at all. In the little space that
was left him, and to avoid crashing into the trees, the pilot had to
bring his craft to earth in such an abrupt dive that it was wrecked
completely. He and the passenger, though, escaped unhurt.
Carelessness has, fairly frequently, played its part in aeroplane
disasters. Sometimes a pilot has been careless, or perhaps in a hurry,
and has failed to locate some defect which, had it been seen and
attended to, would have saved a disaster when a machine was in flight.
Such inattention, which is sufficiently dangerous in the handling of
any piece of mechanism, is deadly in its peril when those who are
guilty of it navigate the air. A man who brings out a machine time
after time, and ascends without examining it carefully, is adding
vastly to the risks that may attend his flight; and the same remark
will apply to the carelessness of mechanics; though as a class, in
view of the arduous nature of their work, and of the long hours they
have frequently to be on duty, with no more than hasty intervals for
rest, their average of care and accuracy is very high. But there have
been cases--mostly in the past though--in which a machine has
developed a structural defect, or some defect say in its control gear,
which ought to have been observed by its mechanics, but which has not
been so detected, and has led to a catastrophe in flight. With
machines built lightly, and subjected to heavy strains when at high
speeds, it is vital that the inspection of such craft, that the
examination of every detail of them, should be carried out in a spirit
of the greatest care. The fraying through of a control wire, unnoticed
by those in charge of a machine, has been sufficient to cause a
disaster; while carelessness in overhauling a motor, a task of supreme
importance, seeing that its engine is the heart of an aeroplane, has
been another cause of accident. It is vital that, when an airman
ascends, both his machine and his motor should be in perfect working
trim. He himself, before he flies, and after his aeroplane has been
wheeled from its shed, should make it a habit to look over the machine,
so as to impose his own personal check upon the work his mechanics
have done.
Even when every care has been taken, and a machine ascends in perfect
trim, there is the human factor, represented by the pilot, which must
be considered always in a study of aeroplane accidents. There is often,
when a catastrophe seems imminent, a choice of things that may be
done. If an engine fails, for instance, under awkward circumstances,
the pilot may have, say, three courses open to him in regard to his
descent. Two may spell disaster and the third safety. It is here that
the innate judgment of a pilot, combined with his experience, will
tell its tale. But this personal element in flying, and particularly
in regard to an accident, is often a very difficult one for which to
make allowances.
The whole problem of aeroplane disasters is, to the analyst, one of
unusual complexity. Take for example the case of a pilot who is flying
alone in his machine, and at an altitude of several thousand feet.
Suddenly something happens; the machine is seen to fall and the pilot
is killed. Experts come to examine the aircraft, but it is wrecked so
completely that little which is reliable can be gathered from any
inspection; while the man who could explain what has happened--the
pilot of the machine--is dead. The statements of eyewitnesses, when
taken on such occasions, are often misleading. One person heard a
crash, and saw something fall away from the machine. Another declares
the engine stopped suddenly and that the machine "fell like a stone."
Another says he is sure he saw one of the wings fold upwards and the
machine swing and fall. And so on. It is extremely difficult, even for
a technical eye-witness, to be sure of what he sees when things happen
quickly and at a distance from him; while the statements of
non-technical people, who are not trained in observation, are
generally so unreliable as to be useless.
It has happened often therefore, far too often, in aeroplane
fatalities that have happened from time to time, that the cause of
such accidents has, even after the most careful investigation, had to
be written down a mystery. But in more than a few cases, though the
evidence has been far from conclusive, it has been considered that a
pilot has been guilty of some error of judgment. There were puzzling
instances, notably in the early days of flying, when airmen began
first to make cross-country flights, of engines being heard to fail
suddenly, and machines seen to fall to destruction. That engines
should break down was not surprising; they were doing so constantly;
but there was no reason why, even if they did fail, a machine should
fall helplessly instead of gliding. But what was thought to have
happened, in more than one of these cases, was that the pilot, through
an error of judgment, had failed to get down the bow of his machine
when his motor gave signs of stopping. The craft concerned were, it
should be mentioned, "pusher" biplanes; and the same rule applied to
them, in cases of engine failure, as has been explained in a previous
chapter, and as is emphasised nowadays in the instruction of the
novice. But in those days the beginner had frequently to learn, not
from wise tuition, but from bitter experience; and he was lucky, often,
if he learned his lesson and still retained his life. On certain
early-type biplanes, for instance, machines with large tail-planes,
and engined as a rule by a motor which was giving less than its proper
amount of power, it was most dangerous for a pilot if, on observing
any signs of failing in his engine, he sought to fly on in the hope
that the motor would "pick up" again, and continue its work. Directly
there was a tendency of the motor to miss-fire, or lessen in the
number of its revolutions per minute, the consequent reduction of the
propeller draught, as it acted on the tail of the machine, would cause
this tail to droop, and the machine to assume very quickly a dangerous
position. And when once it began to get tail-down, as pilots found to
their cost, there was nothing to be done. The machine lost what little
forward speed it had, and either fell tail-first, or slipped down
sideways. Such risks as these, which were very real, were rendered
worse owing to the fact that, in much of the cross country flying of
the early days, pilots flew too low. They lacked the confidence of
those who followed them, and were too prone to hug the earth, instead
of attaining altitude. It was not realised clearly then, as it is now,
that in height lies safety. And so when a machine lost headway through
engine failure, and was not put quickly enough into a glide, it
happened often that it had come in contact with the earth, and had
been wrecked, before there was any chance for the pilot to regain
control, or for the machine itself to exhaust its side-slip, and come
back to anything like a normal position.
But the failure of the human factor in flying, the lack of skill of a
pilot that may lead to disaster, is shown by statistics to play no
more than a small part, when accidents are studied in numbers and in
detail. Some time before the war, in an analysis of the accidents that
had befallen aviators in France--accidents concerning which there was
adequate data--it was shown that only 15 per cent. of them could be
attributed to a failure in judgment or skill on the part of the pilot.
Apart from errors, however, in what may be called legitimate piloting,
there have been regrettable accidents due to trick or fancy flying.
Putting a machine through a series of evolutions, to interest and
amuse spectators, is not of course in itself to be condemned. In such
flying, and notably for instance in "looping the loop," facts were
learnt concerning the navigation of the air, and as to the apparently
hopeless positions from which an aeroplane would extricate itself,
which were of very high value, from both a scientific and practical
standpoint. Public interest in aviation was increased also by such
displays; and it is very necessary that there should be public
interest in flying, seeing that it is the public which is asked to pay
for the development of our air-fleets. But the man who undertakes
exhibition flying needs not only to be a highly-skilled pilot, but a
man also of an exceptional temperament--a man whose familiarity with
the air never leads him into a contempt for its hidden dangers; a man
who will not, even though he is called on to repeat a feat time after
time, abate in any way the precautions which may be necessary for his
safety. In looping the loop, for instance, or in upside-down flying,
it is necessary always that the aeroplane should be at a certain
minimum height above the ground. Then, should anything unexpected
happen, and the pilot lose command temporarily over his machine, he
knows he has a certain distance which he may fall, before striking the
ground; and during this fall the natural stability of his machine,
aided by his own operation of the guiding surfaces, may bring it back
again within control. But if he has been tempted to fly too near the
ground, and has ignored for the moment this vital precaution, and if
something happens for which he is not prepared, then the impact may
come before he can do anything to save himself.
In the early days of flying, when aviators attempted an acrobatic feat,
they ran a far heavier risk than would be the case to-day; and for
the simple reason that their machines, not having a strength
sufficient to withstand any abnormal stresses, were likely to collapse
in the air if they were made to dive too rapidly, or placed suddenly
at any angle which threw a heavy strain on their planes. A machine for
exhibition flying needs to be constructed specially; but this was not
realised till accidents had taught their lesson.
It is a regrettable fact, one which emerges directly from a study of
aeroplane accidents, that many of them might have been avoided had men
been content to follow warily in the footsteps of the pioneers, and
not run heavy risks till they themselves, and the machines they
controlled, had been prepared, by a long period of steady flying, to
meet such greater dangers. The first men who flew realised fully the
risks they ran. But when flying became more general, and men found
machines ready to their hands, machines which it was a simple matter
to learn to fly, this early spirit of caution was forsaken, and feats
were attempted which brought fatalities in their train, and which
seemed to emphasise the risks of aviation, and did it the very bad
service that they fixed in the public mind a notion of its dangers,
and prevented men from coming forward to take up flying as a sport.