I. Flights in thirty-five-mile-an-hour winds—Arguments of sceptics—What
the great contests of 1911 proved.
Reference has been made to the fact that, as soon as engines became
reliable, and airmen gained confidence, winds of an appreciable velocity
were successfully combated.
But even now, despite the strides which the aeroplane is making towards
becoming an all-weather machine, those who belittle it from the military
point of view, and uphold an official policy of inactivity, are found
ready to argue that the heavier-than-air machine is still purely a
fine-weather craft. Such an attitude is governed, not so much by
deep-rooted conservatism, as by ignorance.
The fact is that the wind-flying capabilities of an aeroplane have been
improved to an altogether remarkable extent. So far as an average can be
struck, it may be said that, at the present time, a war machine can be
operated, and can carry out useful work, in a wind blowing at the rate
of from thirty to thirty-five miles an hour. Higher winds are, as has
been said, occasionally combated; but this represents, approximately,
the maximum for practical purposes to-day.
Some military critics, when such facts as these are adduced, raise the
point that such "air-worthiness" as this is not sufficient. The
complications of war are already so great, they declare, that a
Commander-in-Chief is not justified in increasing his responsibilities
by saddling himself with a squadron of aeroplanes, when the machines
will be inoperative should a high wind spring up.
"Enthusiasts do not seem to realise this point," a military critic has
observed, in regard to the general question of aeroplane reliability. "A
commander of troops would, almost, be more hampered than helped by an
air service, were it only possible to use it one day, and then not the
next, and so on. He would rely upon it, you see, and then it would fail
him just at some critical moment. I know it may be said, in answer to
this, that even if only occasional use can be made of aeroplanes, it is
worth while to equip an army with them, because, if they succeed in
their object once in six times, they may alter the whole course of a
battle. But it must be remembered that a very considerable organisation
has to be built up, if an aeroplane service is to be of any real use.
The already huge impedimenta of an army has to be added to; and this,
alone, is a very serious point. On account of the unreliability of the
air service, also, cavalry scouts, and other scouting agencies, have to
be employed, just as usual. The position is, really, a somewhat
unsatisfactory one. For days on end, if the weather is bad, the
aeroplanes may be inoperative."
This view is, of course, an unduly pessimistic one.
Having regard to the capabilities of present-type aeroplanes, the
occasions upon which war machines would be windbound would be very rare.
It is reliably estimated, in fact, that aeroplane scouts would be able
to render good service on 80 per cent, of the days of the year.
It might happen that a boisterous wind, rising in the morning, would
prevent the air-scouts from working at midday, or during the afternoon.
But, even during a generally unfavourable spell of weather, a shrewd
Commander of aeroplanes should be able to snatch an hour’s lull in the
wind, probably in the early morning or evening, and get his machines to
work.
Either a morning or evening calm, during a period of gusty winds, is
generally experienced; and, in any such lull, so rapid is their work,
the aeroplanes should be able to acquire what information is necessary,
and be back again at Headquarters, before any hazardous rising of the
wind takes place.
In this way, it should be possible to manipulate the service, even with
existing machines, so as to make it of practical value, upon almost
every day of a campaign; and the fact that one hour’s work would
probably be sufficient for a reconnoitring flight, is the important
factor of the situation to be remembered.
The point to be made in this connection is this: those who have studied
the progress of aeroplaning, and realise the wonderful strides which
have recently been made, see quite clearly that, even under unfavourable
conditions, a war machine should be able to give a very good account of
itself.
This fact will not be admitted, however, by those who still maintain the
attitude that the aeroplane is a fair-weather machine, and will never be
anything else. Their prejudice will not permit them to read, as they
should, the lessons of recent events. They magnify failures, and ignore
successes.
For such a negative policy there was, at first, some excuse, although
scepticism, at the dawn of a new industry, is the reverse of helpful.
When aeroplanes were in their crudest stage, they provided plenty of
material for the cynic. In those days, pilots spent most of their time
in their hangars, tuning up obstinate engines; and it was a case, as one
humorous pioneer put it, of flying "a mile a month."
The prevailing spirit of scepticism was well revealed in the attitude
taken up by many people in connection with the prize of £10,000 offered
by _The Daily Mail_ for the flight from London to Manchester. To imagine
that such a feat would be accomplished was regarded as ridiculous. And
yet, practically at the first attempt, the flight was made. Then came
the second £10,000 prize by the generous and far-seeing proprietors of
_The Daily Mail_—this time for a 1000-miles aerial tour around Great
Britain, in which rules were introduced to make it incumbent upon pilots
to complete the whole course upon one machine.
Here was a leap, indeed. From 180 miles to 1000! Could it be done? Could
such a reliable aeroplane be found? These were the questions asked; and,
in this connection, one significant fact may be mentioned. It was this:
even some of the experts—men thoroughly well acquainted with the
industry—were doubtful as to whether this prize would be won. They knew,
of course, what giant strides were being made. But, still, so severe was
the ordeal, they had their doubts.
What a triumph this great contest was for the aeroplane will be fresh in
any reader’s memory. Flying neck and neck round the 1010-miles course,
Beaumont and Vedrines astonished the world by the certainty of their
aerial progress.
Calculations as to when the race would finish had been made beforehand.
Reckoning the very highest speeds it would be possible to attain, and
assuming an entire absence of mechanical troubles, it was estimated that
the winner would complete the circuit at a certain hour on a specified
morning; and the winner, Beaumont, was only four hours longer, in
completing the course, than the most favourable estimate had allowed
him.
Even the most enthusiastic supporters of the aeroplane were astonished
by this feat. In flying, which was spread out over several days, and
involved aerial journeys over most difficult country, Beaumont and
Vedrines made light of every adverse condition. In Scotland, they
combated winds so violent that their machines danced and plunged in the
air, and occasionally "side-slipped" for many feet under the treacherous
impulses of unexpected gusts. But, when they were begged to wait a
while, and give the weather an opportunity of improving, these two
champions resolutely took their seats in their monoplanes, and flew on.
The lesson, from the military point of view, was overwhelmingly
important.
Not only did these two men fly with the regularity and speed of express
trains, but they both performed their wonderful feats on machines which
were unchanged throughout. This represented the real progress. In
previous contests of a similar nature, in which long distances had been
traversed, there had been no restriction at all as to the number of
machines used.
The result had been, therefore, that makers of aeroplanes, naturally
anxious to see their representatives win, had dotted spare machines all
over the route; and, in one instance, a competitor used as many as three
aeroplanes before completing one long-distance race.
The point we are immediately concerned with is this. A certain number of
days, chosen a long time ahead, were set apart for this 1000-miles race
round Great Britain; and upon these days it was flown. Beaumont and
Vedrines proceeded from stage to stage, flying to schedule, and making
light of adverse weather. The climatic conditions, as has been said,
were not ideal. When the time came to leave Edinburgh, for instance, so
powerful a wind was blowing that it was not reckoned, even by practical
men, that the pilots would be able to get away.
But, to the amazement even of officials, the two monoplanists soared up,
and deliberately fought the wind. While flying on to the other
stopping-places in Scotland, also, both men passed through heavy storms
of rain; and again, contrary to expectation, they did not descend, but
battled on. The result was that, when this wonderful air race was at an
end, both men were justified in describing their monoplanes as
all-weather machines.
What this performance, and others, have demonstrated is this: at the
present moment, although admittedly experimental, the aeroplane is
sufficiently well able to combat adverse weather as to make it a
highly-useful weapon of war.
II. Value of high speed, when combating a wind—Constructional
difficulties of a hundred-mile-an-hour machine.
It is unwise to regard the capabilities of the present-type aeroplane as
representing, in any way, a limit, or a standard of achievement. What
the machine built to-day can perform, the aeroplane of to-morrow will,
assuredly, be able to improve upon; and so progress will be recorded,
until something in the nature of a perfected aircraft is evolved.
As a matter of fact, there is practically no stage, in connection with
any forms of manufacture, when a builder can say: "Here is a machine
incapable of improvement." Take, as an example, the motor-car. The
luxurious, six-cylindered machine appears to represent what may be
termed "the last word"; but small improvements are constantly being
made, and thoughtful manufacturers still see new avenues of progress.
So it is in regard to the wind-flying capabilities of an aeroplane.
Thirty to thirty-five miles an hour represents, as has been said, a fair
maximum for the strength of wind in which a machine can be navigated at
the present time. But this will not exist long as a standard;
improvements in the speed, and in the general stability of machines, are
being made from day to day.
The result of this progress in manufacture will be that the aeroplane
will be navigable in higher and higher winds. Forty-mile-an-hour winds
will, before long, cease to prevent regular flight; and it is the view
of eminent designers and builders that it will be possible for the
aeroplane to remain aloft in winds blowing at the rate of more than
fifty miles an hour. It is hoped, in fact, that machines will,
eventually, be able to live in any wind save such a raging gale as
drives big steamships to port.
Already, certain definite lines of improvement suggest themselves to the
makers of aeroplanes. In combating a high wind, failing any device to
provide an aeroplane with automatic stability, high speed is found to be
of the greatest aid. But there are difficulties in connection with the
attaining of high speed, as will be shown later.
An illustration of the value of high speed, in overcoming the wind, was
giving at the Rheims flying meeting in the summer of 1910. Morane,
testing a monoplane fitted with a motor of a hundred horse-power,
attained a speed of quite eighty miles an hour. Travelling at this rate,
he found that he was able to pass close behind other machines, despite
the rush of wind from their propellers. Had he been flying a slower
machine, this "back-draught" would, inevitably, have caused him to
capsize.
Speed, also, was what helped Beaumont and Vedrines, when they were
fighting adverse winds in the Circuit of Britain. Beaumont’s monoplane
had a speed of a little over sixty miles an hour; and that of Vedrines
was a trifle faster. Had either of these airmen been piloting a
slow-flying biplane, he would have been forced to descend, seeing that
his machine would have become unmanageable in heavy gusts.
Speed, therefore, is the aim of most manufacturers. They see that the
aeroplane must, if it is to compete commercially with land or sea
transit, provide a means of locomotion more rapid than any which at
present exists; and they recognise, also, that speed offers—at any rate
at present—a solution of the problem of all-weather flying.
But there are, as has been hinted, difficulties in the way of large
increases in speed. Two hundred miles an hour through the air is,
frequently, cited as the ideal to be aimed at. So far, with a
specially-built racing machine, a speed of approximately a hundred miles
an hour has represented the maximum attained. Such machines are,
however, more or less "freaks"; the best results obtained with ordinary
machines being from sixty-five to seventy miles an hour.
Higher speeds still might be thought to be merely a question of
increasing horse-power. But other considerations enter into the
question. A high-speed machine has, it must be remembered, to start away
from the ground, and land again at the end of a flight; its actual
passage through the air is not the only point to be considered.
With a racing monoplane, for example, the small size of its supporting
wings, and the slight camber upon them, necessitate its moving over the
ground at a very high speed before it can obtain the necessary "lift" to
get into the air; and then comes the question of returning to the ground
again. These fast machines will only glide at comparatively high speeds.
A problem arises, therefore, as to the landing chassis which will
withstand the shock of high-speed landings—that is to say, on anything
save perfectly smooth ground. Apart from the question of the skill of
the pilot, in effecting a safe descent at such high speeds—and this is a
factor seriously to be reckoned with—the running-wheels and skids of a
machine will not endure the strain of a landing on anything like a rough
surface.
Thus, were speeds to be pushed, say, to a hundred and fifty miles an
hour, under present conditions of flying, and with any existing method
of building landing mechanism, accidents would be likely to happen, when
airmen came to the point of effecting a descent.
Also to be reckoned with, is the question of increasing the structural
strength of machines in order to meet the wind pressure of very high
speeds.
III. Variable-speed aeroplane—Plans for constructing aircraft of this
type—Advantages of such a machine.
As regards the problem of a fast, and yet reliable aeroplane, which is
an especially important one from the military point of view, seeing that
machines will need to operate over all sorts of country during a
campaign, the view is now taken, by eminent manufacturers, that
something in the nature of a variable-speed aircraft will need to be
devised.
If this can be evolved, it certainly promises a solution of the problem.
What the question resolves itself into, as can be seen, is this: there
are very distinct limits to the rate at which it is practical to move
across the ground on preparing to soar, and also to the speed at which
it is feasible to return again to earth.
The variable-speed machine seems destined to meet these difficulties,
and makers are busy with plans for the building of aeroplanes of this
type. The immediate aim is to produce, if possible, an aeroplane with a
maximum speed approaching, say, a hundred miles an hour, and a minimum
speed of about thirty miles an hour.
In this way, adequate use would be made of the air as a speed medium
and, at the same time, it would be possible to effect satisfactory
landings on fairly rough ground, as well as on smooth surfaces. For the
production of such a variable-speed machine, several designs have
already been prepared; but, as yet, each awaits the ordeal of a
practical test.
One plan, for example, involves the altering of the angle of incidence
of the planes, while a machine is in flight. The angle would, that is to
say, be made steep for slow flight, and flatter when high speed was
required. Another device aims at obtaining variable speed by a process
of reefing the planes of a machine. This would be done by reducing, or
rolling up, the rear extremities of the plane surfaces.
According to this system, a machine would have its slowest speed when
its maximum amount of sustaining surface was in operation, and would fly
faster as the pilot gradually brought into play the reefing process.
A third scheme which is suggested deals with the telescoping of the
plane-ends of a machine, thereby reducing the lifting surface.
Of these methods, the one most favoured, having regard to its
practicability, is that of slightly altering the angle of the planes;
and several manufacturers are already busy with experimental machines of
this type. It appears likely that actual tests will, before long, be
attempted with an aeroplane thus equipped.
For military work, a variable-speed machine promises to be exceptionally
useful. The high speed would be employed in weathering a gusty wind, or
in moving rapidly to any desired locality, when about to carry out a
reconnaissance. Then, when a detailed observation was being made, the
slowest speed would be adopted, so as to give the observer plenty of
opportunity of studying what lay below him.
The production of a practical machine, embodying the principle of
variable speeds, is now held to be merely a question of time, and of
careful experiment. Therefore, the promise of the immediate future,
particularly as regards the military aspect of flying, is most
hopeful—both from the point of view of wind-flying, and of reliability.
One by one, indeed, the objections against the military aeroplane are
likely to be overcome, until a machine is an accomplished fact which
will meet all practical requirements.
IV. Power-plant of aeroplanes—Fitting two engines to obviate involuntary
descents.
While writing of aeroplane development, mention should certainly be made
of engines. It has been shown, already, what a wonderful step forward
was made with the introduction of the revolving "Gnome." This engine
will operate with the reliability of that fitted to a motor-car; there
are other types of engine now achieving thoroughly good results; and
they promise to do better in the future. From the point of view of
propulsion, therefore, the future of the aeroplane appears assured.
One great objection of sceptics, in regard to the power-plant of
aeroplanes, has been that, should an engine fail, a machine is compelled
to make an involuntary descent. In answer to this criticism, advocates
of the aeroplane have pointed out that motors are becoming more and more
reliable, and that such stoppages are already reduced to a minimum.
It is now seen that it will be possible to prevent involuntary descent,
when flying across country, by equipping aeroplanes with a reserve
powerplant.
One of the most interesting experiments, in this regard, is being
carried out by Mr Horace Short, the aeronautical engineer of the Royal
Aero Club.
Mr Short produced, in September, 1911, a biplane fitted with two "Gnome"
engines. One, placed in front of the machine, operated a couple of
tractor propellers fitted before the main-planes. The other, installed
at the rear, actuated a single propeller. The machine was designed so
that one engine would drive it at a speed of about thirty-six miles an
hour; while, if both were employed, its pace would increase to more than
fifty miles an hour. In actual tests, most encouraging results were
obtained with this machine, and Mr Short is now perfecting this type of
twin-engine biplane.
By equipping an aeroplane with two engines, working independently of
each other, the danger of an involuntary descent, on bad ground, is
obviated.
Should one engine stop, the pilot can keep himself in the air with the
other.
In such a machine as this, which might be described as a "safety"
aeroplane, the weight of the additional engine is, of course, a
consideration, but in cases where exceptional reliability is
required—say, for example, when a most urgent dispatch has to be taken
across country from point to point in military operations—a dual-engine
machine will probably be used.
Consideration of such facts as have been cited in this section show that
aeroplanes, for military work, have an almost unlimited field for
improvement. Therefore, any nation which neglects war machines now, on
the argument that they are unreliable, is pursuing an extremely foolish
policy. If feats such as have been recently accomplished are possible,
with machines built with wood, wire, and canvas, what will not be
achieved with the stronger, speedier, heavier aeroplanes, such as are
already being constructed?
Sceptics there are, of course, who may be found ready to say that the
aeroplane will never be made reliable; but their contentions are being
proved to be wrong from day to day. Already, with the simplest possible
apparatus, a remarkable stage of efficiency has been reached. And now
the aeroplane promises to embark upon a new era of construction.
Wood is being replaced by metal; and extreme lightness is no longer the
insistent demand. Aeroplanes are being built for general, everyday use.
From the military point of view, the aeroplanes at present available
have drawbacks. There is, indeed, room for vast improvement. Greater
strength, greater reliability, greater portability—these are the aims
that makers have in view; and they will, without doubt, be realised.
The War Office tests this summer will teach manufacturers many a useful
lesson.