The peculiarities existing between different types of monoplanes become

even more marked than between the biplane and the monoplane. For

example, in piloting a Bleriot monoplane, Fig. 43, it is necessary to

take into account the effect of the engine torque. As the engine rotates

in a right-hand direction, from the point of view of the pilot, the left

wing tends to rise in the air, owing to the depression of the right side

of the machine. The machine also tends to turn to the right, and this

must be counteracted by putting the rudder over to the left. An

aeroplane answers its controls with comparative slowness, with the

exception, perhaps, of the Wright machine, which is noted for its

sensitive and quick response to every movement of the levers. All

control movements must, therefore, be very gentle, as the behavior of an

aeroplane is more like that of a boat than that of an automobile. The

action of the elevator has already been described, and it is, perhaps,

the most difficult of all the controls to manipulate, in that it

requires the exercise of a new sense. The direction rudder is naturally

a more familiar type of control, and in action is similar to the rudder

of a boat.

The torque of the motor renders it advisable for a novice to turn his

machine to the right, if a right-hand propeller be used, and _vice

versa_. If two propellers, turning in opposite directions, are employed,

as in the Wright biplane, there is no inequality from the torque of the

motor. Since torque is not noticeable in straight flying, straightening

out again will always serve the student when he finds himself in trouble

on a turn. When the use of the rudders and ailerons has reduced the

speed, a downward glide will increase it again, and if the motor should

stop on a turn, such a downward glide is immediately imperative. When

the machine is thus gliding, a change in the fore-and-aft balance

becomes at once apparent, because the blast of the propeller no longer

acts on the tail, and the elevator must then be used with greater

amplitude to obtain the same effect.

[Illustration: Fig. 43. Making a Start with Bleriot Monoplane]

Only by constant practice in calm air can the student familiarize

himself with exactly the amount of warping and rudder control to employ

to property offset the lowering of the inner wing in rounding a turn. If

this be not corrected, the whole machine tends to bank excessively and

will be apt to slide downward in a diagonal direction, Fig. 44. This is

a perilous position for the aviator and must be guarded against by the

manipulation of the warping control so as to increase the lift of the

inner wing of a biplane, at the same time, employing the rudder to

counteract this tendency. The use of the rudder is of even greater

importance on the monoplane, as, in this case, warping the inner wing

tends to direct the whole machine downward instead of raising the inner

wing itself. Several bad accidents have resulted from monoplanes

refusing to respond to the warping of the inner wing when making a turn.

In such machines, the rudder must be practically always employed in

connection with the warping of the wings in order to keep the machine on

an even keel, although the controls may not actually be interconnected,

this being one of the grounds on which foreign manufacturers are trying

to make use of the Wright principle, without infringing the Wright

patents, as while they employ warping in connection with the

simultaneous use of the rudder, the controls are not attached to the

same lever as in the Wright machine.

[Illustration: Fig. 44. An Aeroplane "Banking" as it Rounds a Pylon]

Lateral resistance must also be taken into consideration in turning,

otherwise the machine, if kept on an even keel, will tend to skid

through the air and turn about its center of gravity as a pivot. In the

case of an automobile, the resistance to lateral displacement is great,

though on a greasy surface it may be small, as when the machine skids

sideways, a suitable banking of the road being necessary to prevent this

on turns. Many hold that the banking of the aeroplane on turns is only

the direct effect of the turning itself, but the fallacy of this will be

apparent upon a consideration of the law of centrifugal force. It is

obvious that to make a turn, some force must be imparted to the machine

to counteract the effect of the centrifugal force upon the machine as a

whole. And as the sidewise projection of the machine is small, a

compensating force must be introduced. This can be done only by

previously banking up the machine on the outer wing, so that the

pressure of the air under the main plane can counteract the tendency to

lateral displacement. The force then acting under the planes is in a

diagonal direction, and the angle at which it is inclined vertically

depends upon the banking of the planes, it being normal to their greater

dimension. This force can be resolved into two forces, one perpendicular

and one horizontal, the magnitude of each being dependent upon the

degree of banking. When the speed of the machine is higher, the amount

of banking must be greater in order to increase the value of the

horizontal component in proportion to the increase of the value of the

centrifugal force at the higher speed, in spite of the fact that the

forces acting under the planes are also greater due to the higher speed.

As the curve commences, the rudder being put over, the difference of the

pressures on the two wings, owing to their different flying speeds comes

into account, as already explained, and care must be taken that the

banking does not increase abnormally. When the turn is completed, the

rudder is straightened and the machine is again brought to an even keel

with the aid of the wing-warping control, or the ailerons. The effect of

a reverse warping to prevent excessive banking, lowering the inside wing

tip incidentally, puts a slight drag on that wing and assists in the

action of turning, as does also the provision of small vertical planes

between the elevator planes of the original Wright machine. Since the

adoption of the headless type, these surfaces are placed between the

forward ends of the skids and the braces leading down to them.

In making a turn, say, to the left, the outside or right-hand wing is

first raised by lowering the wing tip on that side and the rudder is

then put over to the left. When the correct amount of banking is

acquired, the wing tip is restored to its normal position, and probably

the left wing tip may have to be lowered slightly to increase the lift

on that side owing to its reduced speed. When the turn is completed, the

rudder is straightened out and the left wing tip lowered to restore the

machine to an even keel. Both Glenn Curtiss in this country and R. E.

Pelterie in France have shown that it is possible to maneuver without

using the rudder at all, the ailerons or wing tips alone being relied

upon for this purpose.

Before flights in other than calm air are attempted, much practice is

required. The machine must be inspected over and over again, and the

wind variations studied with a watchful eye. Not until this familiarity

with machine and atmosphere be acquired should flying in a wind be

attempted. To the man on the ground, wind is simply air moving

horizontally, but to the man in the air it is quite different. Not only

must he consider horizontal movement, but vertical draughts and vortices

as well. A rising current of air lifts a machine, a downward current

depresses it, and he must learn to take advantage of the former as the

birds do. Horizontal currents affect forward speed over the ground;

swirls and vortices create inequalities in wind pressure on the planes

and disturb lateral balance. Familiarity with all these atmospheric

conditions can be acquired only after long practice. Against every tree,

house, hill, fence, and hedge beats an invisible surf of air; upward

currents on one side and downward on the other. The upward draught is

not usually dangerous, for it simply lifts the machine; but the down

draught will cause it to drop. A swift downward glide under the full

power of the motor must then be made, to increase the forward speed and

consequently the lift. This explains why it is dangerous to fly near the

ground in a wind; likewise why the beginner should never attempt flying

at first in anything but a dead calm.

_Turning in a Wind_. When turning in a wind, two velocities must be

borne in mind, that of the machine relative to the air and that relative

to the earth. The former is limited at its lower value to that of the

flying speed of the machine, and the latter must be considered on

account of the momentum of the machine as a whole. Change of momentum is

a matter of horse-power and weight and is the governing factor in flying

in a wind on a circular course. Suppose the flying speed of a machine is

a minimum of 30 miles an hour relative to the air, and a wind of 20

miles an hour is blowing. The actual speed of the machine relative to

the earth in flying against the wind will be 10 miles an hour. If it be

desired to turn down the wind, the speed of the machine relative to the

earth must be increased from 10 miles to 50 miles an hour during the

turn and a corresponding change of momentum must be overcome. There are

two ways of accomplishing this, either by speeding up the motor to give

the maximum power, or by rising just previous to making the turn and

then sweeping down as the turn is made, thus utilizing the acceleration

due to gravity to assist the motor. The wind’s velocity will assist the

machine also and during the turn it will make considerable leeway, a

small amount of which is deducted to counteract the centrifugal force of

the machine.

Turning in a contrary direction, _i.e._, up into the wind when running

with it, requires considerable skill, as when flying 50 miles an hour,

the tendency on rounding a corner into a 20-mile-an-hour wind would be

for the machine to rise rapidly in the air. The centrifugal force at

such a speed is also considerable, causing the machine to make much

leeway with the wind during the turn. Turning under such circumstances

should be commenced early, particularly if there are any obstructions in

the vicinity, and considerable skill should be acquired before an

attempt is made to fly in such a wind.

*Starting and Landing*. A machine should always be started and landed in

the teeth of the wind, and no one but the most experienced aviators can

afford to disregard this advice, certainly not the novice. The

precaution is necessary because in landing the machine should always

travel straight ahead without the possibility of lurching and

consequently breaking a wing, as frequently happens. Contact with the

ground is necessarily made at a time when the machine is traveling over

it at a speed of 30 to 40 miles per hour and skidding sideways at 10 to

15 miles per hour, all circumstances which tend to wreck an aeroplane.

*Planning a Flight*. It is easy to lose one’s way in the air. For that

reason it is best to follow the Wright idea of starting out with a

definite plan, and of landing in some predetermined spot, as aimless

wandering about may prove disastrous to the inexperienced aviator, he

may forget which way the wind was blowing, or how much fuel he had, or

the character of the ground beneath him. Should the motor stop, he may

make an all too hasty decision in landing. It is an easy matter to lose

one’s bearings in the air, not only because the vehicle is completely

immersed in the medium in which it is traveling, but also because the

earth assumes a new aspect from the seat of an aeroplane. Cecil Grace

was one of those who lost his bearings and, as a consequence, his life.

Ordinary winds blowing over a level country can be negotiated with

comparative safety. Not so the puffy wind. To cope with that, constant

vigilance is required, particularly in turning. In a circular flight in

a steady wind, the only apparent effect is that the earth is swept over

faster in one direction than in the other. Before a cross-country flight

is attempted, the starting field should be circled over at a great

height, as not until then may the long distance flight be started in

safety. Cross-country flying is, of course, fascinating, and it is a

sore temptation, at an altitude of a few hundred feet, to throw off all

caution and fly off over that strange country below, which is, indeed, a

new land as viewed from aloft. To quote a professional aviator: "Here

the greatest self-restraint must be exercised. Not until the necessary

practice has been acquired, not until the right kind of confidence has

been gained, may one of these trips be attempted, and then only after it

has been properly planned."

*Training the Professional Aviator*. Look back over the achievements in

the air during the comparatively short time that man has actually been

flying, and it will be noted that the beginners, burning up with the

enthusiasm of the novice, have performed the most spectacular feats and

flown with the greatest fearlessness. Curtiss was comparatively new at

aviation when he won the Gordon-Bennett at Rheims in 1909. John B.

Moisant, the sixth time he ever went up in an aeroplane, flew from Paris

to London with a 187-pound passenger and 302 pounds of fuel, oil, and

spare parts. Hamilton made his successful flight from New York to

Philadelphia and return when he was hardly more than a novice, while

Atwood’s great flights from St. Louis to New York and Boston to

Washington were made before his name had become known, and Beachey had

been flying only a few months when he broke the world’s altitude record

at Chicago, while more recent achievements, notably Dixon’s flight

across the Rockies, have emphasized the work of the beginner. All of

this substantiates the belief held at every aviation headquarters in the

country—namely, that the older men already in aviation may improve the

art by executive ability and scientific experiments, but most of them

will degenerate as flyers. Beyond a certain point, frequency of flight

does not necessarily create a feeling of confidence and safety; rather

it brings a fuller appreciation of the dangers, and the men who best

know how to fly are most content to stay upon the ground.

Professional aviators are drawn from every walk of life, but trick

bicycle performers, acrobats, parachute jumpers, and racing automobile

drivers make the most promising applicants. By a kind of sixth sense,

both the Wrights and Curtiss weed out the promising ones after a brief

examination. They select men who have an almost intuitive sense of

balance. Most of these, provided they have nerve, have in them the stuff

of which aviators are made, even though they may have had no experience

in any line akin to aviation. Neither Curtiss nor the Wrights will

accept women under any condition. The Moisant school does not share this

discrimination and trained three women for pilot’s licenses during 1911.

Curtiss and the Wrights are keen in their realization that recklessness

is pulling a wing feather from aviation every time a man is killed, and

they are doing their utmost to promote conservatism. Curtiss said in an

interview:

I do not encourage and never have encouraged fancy flying. I

regard the spectacular gyrations of several aviators I know as

foolhardy and unnecessary. I do not believe that fancy or trick

flying demonstrates anything except an unlimited amount of a

certain kind of nerve and perhaps the possibilities of what is

valueless—aerial acrobatics. Some aviators develop the sense of

balance very rapidly, while others acquire it only after long

practice. It may be developed to a large extent by going up as a

passenger with an experienced man. Therefore, in teaching a

beginner, I make it a point to have him make as many trips as

possible with someone else operating the machine. In this way

the pupil gains confidence, becomes accustomed to the sensation

of flying, and is soon ready for a flight on his own hook. This

is the method used in training army and navy officers to fly. I

have never seen novices more cautious and yet more eager to fly

than these young officers. They have always learned every detail

of their machines before going aloft, and largely because of

this they have developed into great flyers. Perhaps it is due to

the military bent of their minds; at any rate, they have made

good almost without exception.

ACCIDENTS AND THEIR LESSONS

*Press Reports*. Whenever an industry, profession, or what not, is

prominently before the public, every event connected with it is regarded

as "good copy" by the daily press. Happenings of so insignificant a

nature that in any commonplace calling would not be considered worthy of

mention at all, are "played up." This is particularly the case with

fatalities, and the eagerness to cater to the morbid streak in human

nature has been responsible for the unusual amount of attention devoted

to any or all accidents to flying machines, and more especially where

they have a fatal ending. In fact, this has led to the chronicling of

many deaths in the field of aviation that have not happened—some of them

where there was not even an accident of any kind. For instance, in many

of the casualty lists published abroad from time to time, such flyers as

Hamilton, Brookins, and others have figured among those who have been

killed, ever since the date of mishaps that they had months ago.

It will be recalled that five years ago, when the automobile began to

assume a very prominent position, every fatality for which it was

responsible was heralded broadcast where deaths caused by other vehicles

would not be accorded more than local notice. To a large extent, this is

still true and will probably continue to be the case until the

automobile assumes a role in our daily existence as commonplace as the

horse-drawn wagon and trolley car. There is undoubtedly ample

justification for this and particularly for the editorial comment always

accompanying it, where the number of lives sacrificed to what can be

regarded only as criminal recklessness is concerned. Still, the fact

that in a city like New York the truck and the trolley car are

responsible for an annual death roll more than twice as large as that

caused by the automobile, does not call for any particular mention.

Horses and wagons, we have always had with us, and the trolley car long

since became too commonplace an institution around which to build a

sensation.

As the most novel and recent of man’s accomplishments, the conquest of

the air and everything pertaining to it is a subject on which the public

is exceedingly keen for news and nothing appears to be of too trivial

import to merit space. Where an aviator of any prominence is injured, or

succumbs to an accident, the event is accorded an amount of attention

little short of that given the death of some one prominent in official

life. During the four years that aviation has been to the fore, about

104 men and one woman have been killed, not including the deaths of

three or four spectators resulting from accidents to aeroplanes, during

this period—_i.e._, from the beginning of 1908 to the end of 1911. In

view of the lack of corroboration in some cases, the figures are made

thus indefinite. Naturally most of these deaths have occurred in 1910

and 1911—in fact, 50 per cent took place from 1908 to the end of 1910,

and the remainder during 1911, since these years were responsible for a

far greater development, and particularly for a greater increase in the

number engaged, than ever before. More was accomplished in these two

years than in the entire period intervening between that day in

December, 1903, when the Wright Brothers first succeeded in leaving the

ground in a power-driven machine, and the beginning of 1910.

*Fatal Accidents*. Conceding that the maximum number mentioned, 105,

were killed during the four years in question, throughout the world, it

will doubtless come as a surprise to many to learn that this is probably

not quite twice the number who have succumbed to football accidents

during the same time in the United States alone. Authentic statistics

place the number thus killed at 13 during 1908, 23 in 1909, 14 during

1910, and 17 in 1911, or a total of 67. But we have been playing

football for a couple of centuries or more and this is regarded as a

matter of course. The death of a football player occurring in some

small, out-of-the-way place would not receive more than local attention,

unless there were other reasons for giving it prominence, so that, in

all probability, the statistics in question fall far short of the truth,

rather than otherwise.

The object of mentioning this phase of the matter is to place the

question of accidents in its true light. That the development of any new

art is bound to be attended by numerous mishaps, many of them fatal,

goes without saying and it is something that can not be ignored. Nothing

could be worse than attempting to gloss over or belittle the loss of

life for which aviation has been responsible and doubtless will continue

to be. Progress invariably takes its toll and it is more often founded

upon failure than unvarying success, for every accident is a failure, in

a sense, and every accident carries with it its own lesson.

Where the cause is apparent, it gives an indication of the remedy which

will bring about the prevention of its recurrence. In other words, it

serves to point out weaknesses and shows what is necessary to overcome

them. For that reason alone is the question of accidents taken up here,

as a study of those that have occurred points the way to improvement.

Table III gives a resume of the more important fatalities that have

resulted from the use of a heavier-than-air machine during the _past

four years_:

Fatalities greatly increased in number during 1911, but not out of

proportion to the greatly augmented number of aviators. With

comparatively few exceptions, however, the accidents were more or less

similar in their nature to those already tabulated, so that it would be

of no particular value to extend the comparison in this manner to cover

them. Many of the fatalities during that year were not of the aviators

themselves, but of the spectators, a fact which calls attention to a

danger that has not been fully appreciated before. At the start of the

Paris-Madrid race, the French minister of war and another official were

killed by a monoplane plunging into the crowd, and on the same day, May

21, 1911, five people were killed at Odessa, Russia, in the same manner.

An unusual type of mishap, not mentioned in the tabulation and in which

three or four aviators lost their lives during 1911, was the burning of

the aeroplane in midair, or the explosion of the gasoline, setting fire

to the wings and either burning the aviator at his post or killing him

by the fall. One such accident occurred in France in September, another

in Spain two days later, and a third in Germany, in which two men were

killed. Accidents of an even more unusual nature were the collision of

two biplanes in midair at St. Petersburg, the collision of a motorcycle

with a biplane as it swooped down on a race track, and the partial

wrecking of Fowler’s biplane by a bull upon landing near Fort Worth,

Texas, but these, of course, had no bearing on the design of the

machines.

Apart from those specially referred to, the great majority of accidents

during 1911 may be ascribed to two or three of the causes detailed in

connection with the comparative table. Of these, lack of experience and

foolhardiness stand out prominently, the latter undoubtedly causing the

double fatality at Chicago when two aeroplanes plunged into Lake

Michigan, drowning one of the aviators, while a third machine collapsed

in mid-air, hurling the aviator to his death on the field. Careful

reading of the reports of a large number of these accidents usually

brings to light the statement "in attempting to make a quick turn," or

similar phrase, showing that the moving cause of the accident was due to

subjecting the parts of the machine to excessive stresses, as outlined

in the following pages.

*Causes*. _Lack of Experience_. It will be at once noticeable by Table

III that out of a total of 28, no less than 16, or considerably more

than half of the accidents, were due in one way or another to lack of

experience. In other words, the aviators had not fully complied with the

cardinal principle for success in flying upon which the Wright Brothers

have always laid so much stress, _i.e._, you must first learn to fly

before you can attempt to go aloft safely. Nothing short of a thorough

mastery of the machine can suffice to give the aviator the ability to do

the right thing at the right moment, in the great majority of cases.

There will always be occasions when even the most skilled aviator will

make errors of judgment and frequently they cost him his life. But this

is equally true of every dangerous calling, whether it be running an

automobile, driving a locomotive, or doing any of the thousand and one

things where the responsibility for his own and other lives is placed in

one man’s hands and depends to a large extent on his discretion and

judgment in cases of emergency, so that there will be fatalities from

this cause as long as man continues to fly. This involves the personal

equation that must always be reckoned with. Just how many of the

accidents that have resulted in the fatalities set forth, have been due

to the fallibility of the operator and for how much the design of the

current types of machines is responsible, would be hard to say. Fig. 45,

for example, which shows H. V. Roe in the act of striking the ground in

his triplane, illustrates an accident due to bad design. Methods of

control will be improved and simplified and made as nearly "fool-proof"

as human ingenuity can accomplish, but experience in other fields has

demonstrated unmistakably that they can never be developed to a point

where it is impossible to do the wrong thing. With skill at such a

premium in callings of responsibility which involve only conditions that

have been familiar for years, how much more so must it be in the air

about which so little is known? Consequently, the real danger is to be

found in the personal equation, just as it is in every other mode of

conveyance, despite the fact that it has been perfected to a point which

apparently admits of little further development where safe-guarding it

is concerned.

[Illustration: Fig. 45. Roe’s Multiplane as it Struck the Ground. An

Accident Due to Poor Design]

[Illustration: Fig. 46. DeLessep’s Machine after Striking an

Obstruction]

[Illustration: Fig. 47. Overturned Monoplane Due to a Start in a Gale]

*Obstructions*. Obstructions are bound to play a prominent part in

accidents to any method of conveyance, but less so in aviation than in

any other, as it is only in rising and alighting that this danger is

present. Of the two fatal accidents ascribed to this cause, one resulted

from colliding with an obstruction while running along the ground

preparatory to rising, and the other from striking an obstruction in

flight, Fig. 46. In view of the numerous cross-country flights that have

been made, trips across cities and the like, it is to be marveled at

that up to the present writing no fatalities have been caused by what

the aviator most dreads when leaving the safety of the open field, that

is, being compelled to make a landing through stoppage of the motor,

whether from a defection or lack of fuel. While no fatalities have as

yet to be put down to this ever-present danger in extended flights, an

accident that might have had a fatal termination, occurred to Le Blanc

during the competition for the Gordon-Bennett trophy, which was the

chief event of the International Meet in October, 1010, at Belmont Park,

near New York. Le Blanc and his fellow compatriots who were eligible

were all experienced cross-country flyers, the former having won the

_Circuit de L’Est_, a race around France, and by far the most ambitious

of its kind which had been attempted up to that time. They accordingly

protested most vigorously against flying over the American course to

compete for the cup which Curtiss had captured at Rheims the year

before, owing to the fact that it presented numerous dangerous

obstructions in the form of trees and telegraph poles. But as it was

impossible to provide any other convenient five-kilometer circuit (3.11

miles) as called for by the conditions, the protest was of no avail.

After having covered 19 of the 20 laps necessary to complete the

distance of 100 kilometers in time that had never been approached

before, Le Blanc was compelled to descend through lack of fuel, and as

he had not risen more than 80 to 100 feet at any time during the race,

this meant coming down the moment the motor stopped. The result was a

collision with a telegraph pole, breaking it off and wrecking the

monoplane, the aviator fortunately escaping any serious injury. During

the same meet Moisant demolished his Bleriot monoplane by trying to

start in the face of a high wind, Figs. 47 and 48.

[Illustration: Fig. 48. View of Moisant Monoplane after a Bad Spill]

*Stopping of Motor*. The mere fact that the motor stops does not

necessarily mean a disastrous ending to a flight, as is very commonly

believed, this having been strikingly illustrated by Brookins’ glide to

earth from an altitude of 5,000 feet with the motor dead, and Moisant’s

glide from an even greater height in France. But it does mean a wreck

unless a suitable landing place can be reached with the limited ability

to control the machine that the aviator has when he can no longer

command its power. Motors will undoubtedly become more and more reliable

as development progresses, but the human equation—the partly-filled fuel

tank, the loose adjustment that is overlooked before starting, and a

hundred and one things of a similar nature—will always play their role,

so that compulsory landing in unsuitable places will always constitute a

source of danger as flights become more and more extended.

*Breakage of Parts of Aeroplanes*. In studying the foregoing table, it

can only be a source of satisfaction to the intelligent student and

believer in aerial navigation, to note how large a proportion of the

accidents is due to the breakage of parts of the machine. This implies a

fault in construction, but not in principle. It reveals the fact that,

in the attempt to secure lightness, strength has sometimes been

sacrificed, chiefly through lack of appreciation of the stresses to

which the machine is subjected in operation. At a time when weight is

regarded almost as the paramount factor by so many builders, it is

inevitable that some should err by shaving things too fine. Lightness is

an absolute necessity and failure to achieve it in every instance

without eliminating the factor of safety has been due more to the crude

methods of construction and lack of suitable materials, than any other

cause—conditions that are bound to obtain in the early days of any art.

Construction is improving rapidly, but progress is bound to be attended

with accidents of this nature. The fact that their proportion is greatly

diminishing despite the rapidly increasing number of aviators is the

best evidence of what is being accomplished. When machines are built

with such a high factor of safety in every part that breakage is an

almost unheard-of thing, failures from this cause will have been reduced

to an unsurpassable minimum.

*Failure of the Control Mechanism*. Under the general classification B,

are included not alone those accidents directly due to breakage of some

vital part, but also those instances in which some element of the

control, such as the elevator, has become inoperative through jamming.

When an accident happens in the air, it takes place so quickly and the

machine is so totally wrecked by falling to the ground, that it is

usually difficult to determine the exact nature of the cause through a

subsequent examination of the parts, so that it can seldom be stated

with certainty just what the initial defection consisted of, though it

may be regarded as a foregone conclusion that, in the case of

experienced aviators who have previously demonstrated their ability to

cope with all ordinary emergencies, nothing short of the failure of some

vital part could have caused their fall.

This was the case with Johnstone’s accident at Denver—an occurrence

illustrating another phase of the personal equation that must be taken

into consideration when noting the lessons to be learned from a study of

accidents and their causes. It is simply the old, old story of

familiarity breeding contempt—the miner thawing out sticks of dynamite

before an open fire. Due to the rarefied air of Denver, which is at an

elevation of more than 5,000 feet, Johnstone had underestimated the

braking powers of the air on the machine in landing the day previous and

had crashed into a fence, breaking one of the right outermost struts

between the supporting planes.

Proper regard for safety should naturally have called for its

replacement by an entirely new strut, but conditions at flying meets as

at present conducted make quick repairs to damaged machines imperative.

The damaged upright was accordingly glued and braced by placing iron

rings around it, the rings themselves being held in place by ordinary

nails passing through holes in the iron large enough to let the nail

head slip through. The vibration of the motor and the straining of the

strut in warping the wings caused the nails to work out of the holes,

permitting the rings to slide out of place as well. Johnstone was an

accomplished aviator, much given to the execution of aerial maneuvers

only possible to the skilled flyer of quick and ready judgment. But such

performances impose excessive stresses on the supporting planes and

their braces, and one of Johnstone’s quick turns caused the repaired

struts to collapse through the strain of sharply warping the wing tips

on that side. He immediately attempted to restore the balance of the

machine by bringing the left wing down with the control, then tried to

force the twisting on the right side, succeeding momentarily, and a few

seconds later losing all control and crashing to the ground. It appeared

to demonstrate that even when disabled an aeroplane is not entirely

without support, but has more or less buoyancy—something which is really

more of an optical illusion than anything else due to underestimating

the speed at which a body falls from any great height. Johnstone’s

accident was the first of its kind, in that he fell from a height of

about 800 feet, during the first 500 of which he struggled to regain

control of the machine, finally dropping the remaining 300 feet

apparently as so much dead weight. It showed in a most striking manner

the vital importance of the struts connecting the supporting surfaces of

the biplane, any damage to them resulting in the crippling of the

balancing devices and the end of all aerial support.

*Biplane vs. Monoplane*. It requires only a glance at Table III to show

that the greater number of accidents have happened to the biplane, yet

the latter is generally regarded as the safer of the two. Prior to

Delagrange’s fatal fall in January, 1910, there had been only four

fatalities with modern flying machines: Selfridge and Lefebre were

killed in Wright machines, the latter of French manufacture, Ferber lost

control of his Voisin biplane, and Fernandez was killed flying a biplane

of his own design. In one case at least, that of Lieutenant Selfridge,

the accident appears to have been due to the failure of a vital part—the

propeller. It has since become customary to cover the tips of propellers

for at least a foot or so with fabric tightly fitted and varnished so as

to become practically an integral part of the wood. This prevents

splintering as well as avoiding the danger of the laminations succumbing

to centrifugal force and flying apart. At the extremely high speeds,

particularly at which direct-driven propellers are run, the stress

imposed on the outer portion of the blades by this force is tremendous.

In making any attempt to compare the number of accidents to the biplane

and the monoplane, it must also be borne in mind that the former has

been in the majority.

Delagrange’s accident offers two special features of technical interest.

It was the first fatality to happen with the monoplane and was likewise

the first fatal accident which appeared to be distinctly due to a

failure of the main structure of the machine. For obvious reasons, it is

usually difficult to definitely fix the cause of an accident, but in

this case there seemed good reason to suppose that the main framing of

one of the wings gave way altogether. Curiously enough, Santos-Dumont

had an accident the day following from an exactly similar cause, the

machine plunging to the ground. But with the good fortune that has

attended the experimenter throughout his long aerial career, he was

uninjured. It was definitely established that the cause was the fracture

of one of the wires taking the upward thrust of the wing. In the case of

the biplane, the top and bottom members are both of wood, with wooden

struts, the whole being braced with numerous ties of wire. In the

monoplane, however, the main spars are trussed to a strut below by a

comparatively small number of wires. The structure of each wing is, in

fact, very much like the rigging of a sailboat, the main spars taking

the place of the mast while the wire stays take that of the shrouds,

with this very important difference, that the mast of the boat is

provided with a forestay to take the longitudinal pressure when going

head to the wind, while the wing of an aeroplane often has no such

provision, the longitudinal pressure due to air resistance being taken

entirely by the spar.

It is quite possible that this had something to do with Delagrange’s

accident, as, in the effort to make a new record, his Bleriot had just

been fitted with a very much more powerful motor. In fact, double that

for which the machine was originally designed, and this was given by the

maker as the probable cause of the mishap. As the new motor was of a

very light type, the extra weight, if any, was quite a negligible

proportion of the total weight of the machine. The vertical stresses on

the wings and their supporting wires would, therefore, not be materially

increased. But as the more powerful engine drove the wings through the

air a great deal faster, the stresses brought upon them by the increased

resistance would be substantially augmented and, unless provision were

made for this, the factor of safety would be much reduced. Whether the

failure of the wing was actually from longitudinal stress or the

breaking of a supporting wire, as in Santos-Dumont’s case, will never be

known, but it is quite clear that the question of ample strength to

resist longitudinal stresses should be carefully considered, especially

when increasing the power of an existing machine.

The question of the most suitable materials and fastenings for the

supporting wires is, moreover, a matter which requires very careful

consideration. In the case of the biplane, the wires are so numerous

that the failure of one, or even more, may not endanger the whole

structure, but those of the monoplane are so few that the breaking of

but one may mean the loss of the wing. In this respect, as in others,

the conditions are parallel to the mast of the sailboat. It is only

reasonable to expect, therefore, that similar materials would be best

adapted to the purpose. At present, however, the stays of aeroplane

wings are almost invariably solid steel wire, or ribbon, while marine

shrouds are always of stranded wire rope, solid wire not having been

found satisfactory. Weight for weight, the solid wire will stand a

greater strain when tried in a testing machine than will the stranded

rope, but practice has always demonstrated that it is not so reliable.

The stranded rope never breaks without warning, and sometimes several of

its wires may go before the whole gives way. As the breakage of the

strands can be easily seen, it is possible to replace a damaged stay

before it becomes unsafe. In the case of a single wire, there is nothing

to show whether it has deteriorated or not. It seems a doubtful policy

to use in an aeroplane what experience has shown not to be good enough

for a boat, and stranded wire cables particularly designed for

aeronautic use are now being placed on the market in this country.

*Record Breaking*. Striving after records has undoubtedly proved one of

the most prolific causes of accident. What is wanted to make the

aeroplane of the greatest practical use is that it should be safe and

reliable. The tendency of record-breaking machines is the exact opposite

of this, as the weights of all the most essential parts must be cut down

to the finest limits possible in order to provide sufficient power and

fuel-carrying capacity for the record flight. It is, in fact, generally

the case in engineering that the design and materials which will give

the best results for a short time are essentially different from those

which are the most reliable, and striving after speed records consists

simply in disregarding safety and reliability to the greatest extent to

which the pilots are willing to risk their necks, and there is no

difficulty in getting men to take practically any risk for the

substantial rewards offered.

The performance of specially sensational feats in the air is likewise a

fertile source of accidents. One noted aviator who has the reputation of

being a most conservative and expert operator, while endeavoring to land

within a set space, made too sudden a turn, which resulted in the tail

of the machine giving way, precipitating him to the ground. In fact, the

number of failures resulting from abrupt turns shows conclusively that

there is too small a factor of safety in the construction, not because

the added weight could not be carried, but because the extreme lightness

alone made possible the stunts for which there is always applause or

financial reward. It may seem strange to the man whose only interest in

aeronautics is that of an observer, that so many should be willing to

take such unheard-of chances; that an aeronaut will rise to great

heights, knowing in advance that a vital part of his machine has been

deranged, or is only temporarily repaired; and that many others will

attempt ambitious flights with engines or other parts that have never

been tested previously in operation in the air. Many young and

inexperienced aviators are not content to thoroughly test out each new

part on the ground, or close to it, but must go aloft at once to do

their experimenting, with the usual result of such foolhardiness. If in

other sports safe conditions were absolutely disregarded in this

manner—take football as an instance—the resulting fatalities would not

be charged against the sport itself. But aviation is so extremely novel

and likewise so mysterious to the uninitiated that this is never taken

into consideration.

*Excessive Lightness of Machines*. If, even at the present early stage

of aviation, machines are being made excessively light for purposes of

competition, it is time that the contest committees of organizations in

charge of meetings formulate rules as to the size of engines, weight of

machines, and similar factors, so that accidents will not only be

reduced to a minimum, but competition along proper lines will develop

types of machines which are useful and not merely racing freaks, as has

already been done in the automobile field. Hair-raising performances

also should be prohibited, at least until such time as improvements in

the construction of machines make it reasonably certain that they are

able, to withstand the terrific strains imposed upon them in this

manner. Suddenly attempting to bring the machine to a horizontal plane

after a long dip at an appalling angle is an extremely dangerous

maneuver, whether it be taken in the upper air or is one of the now

familiar long glides to earth, which require pulling up short when

within a few feet of the ground and after the dropping machine has

acquired considerable inertia. The aviator is simply staking his life

against the ability of the struts and stays to withstand the terrific

stresses imposed upon them every time this is done.¹

As at present constructed, many of the machines are not sufficiently

strong to withstand the utmost in the way of speed and sudden turns

which the skilled operator is likely to put on them. They should be made

heavier, or of materials providing greatly increased strength with the

same weight. That they can be made heavier without seriously damaging

their flying ability has been clearly demonstrated by the numerous

flights with one and two passengers, and on one occasion in which three

passengers besides the driver were taken up on an ordinary machine. This

was likewise tempting fate by overloading, but it served to show the

possibilities.

[Illustration: Fig. 49. Monoplane is Liable to Stand on its Head if

Landing is Not Properly Made]

*Landings*. Then there is a class of accidents for which neither the

aviator nor the machine is responsible, as where spectators have crowded

on the field, causing the flyers to make altogether too sudden or

impromptu landings at angles which would otherwise not be considered for

a moment. This, of course, refers solely to exhibition meets, and the

comparative immunity of cross-country flights from fatal accidents as

compared with the latter, speaks for itself in this respect. In the

open, even the novice seems to be able to pick a safe landing,

especially if high enough to glide some distance before reaching the

ground. This brings out the fact that, as a rule, the machines are safer

in the air—a large part of the danger lies in making a landing. Starting

places are usually smooth, but landing places may be the reverse. When

alighting directly against the wind, which is the only safe practice,

most of the machines will remain on an even keel until they come to a

stop, but the slightest bump or depression, in connection with a side

gust of wind, may swerve it around and capsize it, as demonstrated by

the illustration of a bad landing by De Lesseps, Fig. 49. This was

emphasized by some of the minor accidents at the International Meet near

New York. There is no precision or accuracy in the movements of a flying

machine when rolling slowly over the ground after the engine has been

shut off, and the aviator is, to a certain extent, helpless. The wheels

on most machines are placed too near the center and too close together.

When an attempt is made to land with the wind on the quarter or side,

although the machine may strike the ground safely, owing to the accuracy

with which it may be controlled in the air while at speed, it is apt to

turn after rolling a short distance and the wind will then easily

capsize it, breaking a wing, smashing a propeller, and sometimes

injuring the motor or the aviator. Accidents from this cause have been

common.

These accidents and collisions with obstructions make plain the fact

that brakes are quite as necessary on an aeroplane as on any other

vehicle intended to run on the ground. Practically all aeroplanes are

fitted with pneumatic tires and ball-bearing wheels and, as there is

very little head resistance, they will run a considerable distance after

alighting at a speed of 20 to 30 miles an hour. The employment of a

brake on the wheels would have averted one of the fatal accidents

abroad, as noted in Table III. They would have enabled Johnstone to stop

his machine before colliding with the fence surrounding the aviation

grounds at Denver, and they would have prevented several minor accidents

at various meets, which, though not endangering the aviator in every

instance, have often seriously damaged his machine. Every exhibition

field is obstructed by fences, posts, buildings, and the like, and to

avoid coming in contact with these, as well as with the irrepressible

spectator, the aviator should certainly have an effective means of

bringing the machine to a standstill when it is running along the

ground. How much more so is this necessary for cross-country flying when

the choice of a landing place is a difficult matter at best. Ability to

come to a stop quickly would make it possible to land in restricted

places where only a very limited run along the ground could be had.

*Lack of Sufficient Motor Control*. Another class of accidents that take

place on the ground suggests the necessity for improving the motor

control. In alighting, the motor is usually stopped by cutting off the

ignition—ordinarily by grounding or short-circuiting. Throttling to stop

appears to be seldom resorted to, but as several instances have occurred

in which the aviator found it impossible to cut off the ignition,

resulting in a collision with another machine or a building, it is

evident that the control should be arranged so that both methods could

be employed. With the increasing use of air-cooled motors that may

continue to run through self-ignition after the spark has been cut off,

this is more necessary than ever.

While it has been demonstrated that the stoppage of the motor does not

necessarily involve a fall, most aviators will naturally prefer to

command the assistance of the motor at all times, and in the case of

motors using a carbureter this should be jacketed either from the

cooling water or the exhaust, and means provided for increasing the air

supply to prevent the motor stopping at a great height owing to the cold

and the rarefied air. The reasons for this have been gone into more at

length under the heading of "Altitude." With these and similar

improvements that will be suggested by experience and further accidents,

there appears to be no reason why aviation can not be made as safe as

the personal equation will permit it to be. There will always be

reckless flyers. Ignorance and incompetence can not be altogether

eliminated any more than they can in sailing, hunting, or any other

sport. The annual hunting fatalities from these causes in this country

alone make a total beside which the aggregate of four years in aviation

the world over, is but an insignificant fraction.

*Parachute Garment as a Safeguard*. To save as many as possible of these

reckless ones from themselves, so to speak, a parachute garment has been

devised to ease the shock of the fall. It will be recalled that Voisin

would not fly in his biplane until he had provided himself with a

heavily-padded helmet, somewhat on the order of the football headpiece.

But neither a padded headpiece nor padded clothing would avail much

against a fall of any kind from an aeroplane; hence, the parachute

garment. Its object is not to take the shock of a fall, as are the pads,

nor is it to prevent a fall, but to reduce the rate of drop by

interposing sufficient air resistance to make the fall safe. This new

parachute is in the form of a loose flowing garment, securely fastened

to the body and fitted over a framework carried on the aviator’s back.

The lower ends of the garment are secured to the ankles. The arrangement

is such that when the aviator throws out his arms, the garment is

extended somewhat in umbrella or parachute form, thus creating

sufficient resistance to prevent too rapid a descent. Experiments have

been made with this parachute dress in which the wearer has jumped from

buildings, cliffs, and other heights, and the garment has assumed its

role of parachute at once, permitting a safe and easy descent.

*Study of Stresses in Fancy Flying*. To sum up, it will be seen that the

most prolific cause of fatalities is the personal equation. Of all the

many dangers encountered in aeroplaning, one of the most clearly

defined, as well as one of the most seductive, results from fancy

flying: from wheeling round sharp, horizontal curves; from conic

spiraling; from cascading, swooping, and undulating in vertical plane

curves, popularly dubbed "stunts." These are forms of flying in which

aviators constantly vie with one another. They frequently result in

imposing stresses upon the machine which are far beyond its capacity to

withstand. The danger is particularly alluring to reckless young

aviators engaged in public exhibitions. The death of St. Croix

Johnstone, at the Chicago Meet in the summer of 1911, affords a typical

illustration of what may be expected as the result of such performances.

Nevertheless, partly because they do not adequately appreciate the risk,

and largely, no doubt, because of the liberal applause accorded by an

admiring throng which also fails to realize the hazardous nature of the

fascinating maneuvers, there will doubtless always be aviators to

undertake such feats.

Singularly enough, the exact magnitude of such hazards, or more

accurately, the extent of the increased stress in the machine, though

beyond even the approximate guess of the aviator, is capable of nice

computation in terms of the speed and curvature of flight. During an

exhibition meet in Washington, D. C, during the summer of 1911, Glenn H.

Curtiss found difficulty in restraining one of his young pupils from

executing various hair-raising maneuvers. He would plunge from a great

elevation to acquire the utmost speed, then suddenly rebound and shoot

far aloft. He would undulate about the field, and on turns would bank

the machine until the wings appeared to stand vertical. Curtiss solemnly

warned the young aviator and earnestly restrained him, pointing out the

dangers of sweeping sharp curves at high speed, of swooping at such

dangerous angles, and the like. Curtiss then turned to A. F. Zahm and

expressed the wish that someone would determine exactly the amount of

the added stress in curvilinear flight. The following, published by

Zahm, in the _Scientific American_, gives the method of calculating

this:

When a body pursues a curvilinear path in space, the centripetal force

urging it at any instant may be expressed by the equation

Fn = m(V/R)² (absolute units) = (m/g)(V²/R) (gravitational units)

in which _Fn_ is the centripetal force, _m_ the mass of the body, _V_

its velocity, and _R_ the instantaneous radius of curvature of the path

followed by its center of mass. Since the mass may be regarded as

constant for any short period, the equation may be expressed by the

following simple law:

_The centripetal force varies directly as the square of the velocity of

flight and inversely as the instantaneous radius of the curvature of its

path._

In applying the above equation to compute the stress in an aeroplane of

given mass _m_, we may assume a series of values for _V_ and _R_,

compute the corresponding values for _Fn_, and tabulate the results for

reference. Table IV has been obtained in this manner. It may be noted

that on substituting in the equation, _V_ is taken as representing miles

per hour, _R_ as feet, and _g_ as 22 miles an hour, in order to simplify

the figuring, this being 32.1 feet per second. The table shows at a

glance the centripetal force acting on an aeroplane to be a fractional

part of the gravitational force, of weight of the machine and its load.

For example, if the aviator is rounding a curve of 300 feet radius at 60

miles per hour, the centripetal force is 0.55 of the total weight. At

the excessively high speed of 100 miles per hour and the extremely short

radius of 100 feet, the centripetal force would be 4.55 times the weight

of the moving mass. The pilot would then feel heavier on his seat than

he would sitting still with a man of his own weight on either shoulder.

For speeds below 60 miles per hour and radii of curvature above 500

feet, the centripetal force is less than one third of the weight. The

table gives values for speeds of 30 to 100 miles per hour, by increments

of 10 miles and for radii of curvature of 100 to 500 feet, by increments

of 100 feet, so that intermediate speeds and radii may readily be

calculated.

The entire stress on the aeroplane in horizontal flight, being

substantially the resultant of the total weight and the centripetal

force, can readily be figured by compounding them. Thus in horizontal

wheeling, the resultant force as shown in the diagram, Fig. 50, is

approximately

_F = √(Fn²+W²)_

In swooping, or undulating in a vertical plane, the resultant force at

the bottom of the curve has its maximum value

_F = (Fn+W)_

and at any other part of the vertical path, it has a more complex though

smaller value, which need not be given in detail.

It is obvious that the greatest stress on the machine occurs at the

bottom of a swoop, if the machine be made to rebound on a sharp curve.

The total force _(Fn+W)_ sustained at this point may be found from the

table, if _V_ and _R_ be known, simply by adding 1 to the figures given,

then multiplying by the weight of the machine. For example, if the speed

be 90 miles per hour and the radius of curvature 200 feet, the total

force on the sustaining surface would be 2.84 times the total weight of

the machine. In this case, the stress on all parts of the framing would

be 2.84 times its value in level flight, when only the weight has to be

sustained. The pilot would feel nearly three times his usual weight.

[Illustration: Fig. 50. Force Diagram in Horizontal Wheeling]

From the foregoing, it is apparent that in ordinary banking at moderate

speeds on moderate curves, the additional stress due to centripetal

force is usually well below that due to the weight of the machine, and

that in violent flying, the added stress may considerably exceed that

due to the weight of the machine and may accordingly be dangerous,

unless the aeroplane be constructed with a specially high factor of

safety. But there is nothing in the results here obtained that seems to

make sharp curving and swooping prohibitive. If the framing of the

machine be given an extra factor of safety, at the expense perhaps of

endurance and speed, it may be made practically unbreakable by such

maneuvers, and still afford to the pilot and spectators alike all the

pleasures of fantastic flying.

*Methods of Making Tests*. In order to obtain actual data for the

fluctuations of stress in an aeroplane in varied flying, it is suggested

that the stress or strain of some tension or compression member of the

machine be recorded when in action; or simpler still, perhaps, that a

record of the aeroplane’s acceleration be taken and particularly its

transverse acceleration. A very simple device to reveal the transverse

acceleration of an aeroplane in flight would be a massive index

elastically supported. A lath or flat bar stretching lengthwise of the

machine, one end fixed, the other free to vibrate, and carrying a pencil

along a vertical chronograph drum, would serve the purpose. This could

be protected from the wind by a housing as shown in the sketch, Fig. 51.

[Illustration: Fig. 51. Method of Boxing an Acceleration Recorder]

An adjustable sliding weight could be set to increase or diminish the

amplitude of the tracing, and an aerial or liquid damper could be added

to smooth the tracing. The zero line would be midway between the

tracings made on the drum by the stationary instrument when resting

alternately in its normal position and upside down; the distance between

this zero line to the actual tracing of the stationary instrument would

be proportional to the aeroplane stresses in level, rectilinear flight;

while in level flight on a curve, either horizontal or vertical, the

deviation of the mean tracing from the zero line would indicate the

actual stress during such accelerated flight. Of course, the drum could

be omitted and a simple scale put in its place, so that the pilot could

observe the mean excursion of the pencil or pointer from instant to

instant; also, the damper of such excursion could be adjusted to any

amount in the proposed instrument if the vibrating lath fitted its

encasing box closely with an adjustable passage for the air as it moved

to and fro; or if light damping wings were added to the lath, or flat

pencil bar.

Another method would be to obtain by instantaneous photography the

position of the centroid of the aeroplane at a number of successive

instants, from which could be determined its speed and path, or _V_ and

_R_ of the first equation, by which data, therefore, the stress could be

read from Table IV.

Perhaps the simplest plan would be to add an acceleration penholder,

with its spring and damper, to any recording drum the aeroplane may

carry for recording air pressure, temperature, speed, and so forth.

Indeed, all such records could be taken on a single drum.

A score of devices, more or less simple, but suitable for revealing the

varying stress in an aeroplane, will occur to any engineer who may give

the subject attention. And it is desirable in the interests both of

aeroplane design and of prudent manipulation that someone obtain roughly

accurate data for the stresses developed in actual flight.

*Increment of Speed in Driving*. It is commonly supposed by aviators

that the _increment_ of speed due to driving is very prodigious. An easy

formula will determine the major limit of such speed increment. If the

initial and natural speed of the aeroplane be _v_, and the change of

level in diving be _h_, while the speed at the end of the dive be _V_,

the minimum change of level necessary to acquire any increment of speed,

_V—v_, may be found from the equation

h = (V - v)/2g

If, as before, _g_ be taken as 22 miles per hour, the equation reduces

to the convenient formula

h = (V-v)/30

in which _V_ and _v_ are taken in miles per hour. Assuming various

values for _V_ and _v_, Table V has been found for the corresponding

values of _h_ in feet: For example, if the natural speed of the

aeroplane in level flight be 50 miles per hour, and the aviator wishes

to increase the speed by 20 miles per hour, he must dive at least 80

feet, assuming that the aeroplane falls freely, like a body in vacuo, or

that its propeller overcomes the air resistance completely; otherwise

the fall must be rather more than 80 feet.

It has been suggested that a contest be arranged to determine which

aviator could dive most swiftly and rebound most suddenly, the prize

going to the one who should stress his machine most as indicated by the

accelerograph above proposed. But to avoid danger, the contest would

have to be supervised by competent experimentalists, and would be best

conducted over water. It is safe to say that more than one well-known

aeroplane would be denied entry in such a contest because of lack of a

sufficient factor of safety in its construction.

*Dirigible Accidents*. Because its wrecks are spectacular and the loss

involved tremendous, the dirigible has probably earned an undeserved

reputation, though it must be admitted that the big airships have come

to grief with surprising regularity. The fact must be noted, however,

that when an airplane is wrecked, the aviator seldom escapes with his

life, while the spectators’ lives are endangered to an even greater

extent, whereas in the case of the dirigible, the loss is simply

financial, both the crew and passengers usually escaping without a

scratch. This is largely due to the fact that the majority of accidents

to dirigibles have happened on the ground, and have been caused by lack

of facilities for properly handling or "docking" the huge gas bag. Of

course, lack of flotation or an accident to the motors, or both

combined, have brought two of the numerous Zeppelins to earth in a very

hazardous manner, though no one was killed, while four French army

officers lost their lives in the Republique disaster, the exact cause of

which was never definitely ascertained. This was likewise the case with

Erbsloeh and his companion who were dropped from the sky, their airship

having taken fire. It was thought that ignition was caused by

atmospheric electricity, in this instance.

By far the great majority of later dirigible accidents have been due

solely to the crude methods of handling the airships on the ground, and

the frequency with which these have occurred should certainly have been

responsible for the adoption of improvements in this respect at an

earlier day.

For instance, the Morning Post, a big Lebaudy type bought for English

use, had the envelope ripped open by an iron girder projecting from its

shed. Repairs took several months, and at the end of the first trial

thereafter, the ship was again Wrecked in landing. A company of soldiers

failed to hold the big craft and it drifted broadside into a clump of

trees, hopelessly wrecking it. In attempting to dock the Deutschland I,

200 men were unable to hold it down, a heavy gust of wand catching the

big airship and pounding it down on top of a wind break that had been

specially erected at the entrance of the shed for protection. A similar

accident happened to the big Parseval, a violent gust of wind casting it

against the shed and tearing such a hole in the envelope that the gas

rushed out and the car dropped 30 feet to the ground. The big British

naval dirigible of the rigid type, the Mayfly, was broken in half in

attempting to take it out of the shed the first time. A cross wind was

blowing and the gas bag of one of the central sections was torn,

deflating it and showing in a striking manner that the solidity of a

rigid dirigible results chiefly from the aerostatic pressure of the gas

in its various compartments. Without the gas lift, a rigid frame is so

in reality only for certain limited distances, as was shown by the total

collapse of the Mayfly’s frame after having been subjected to the

opposed leverage of the parts on either side of the original break.

This, of course, was an error in design, as the frame of a rigid

dirigible should certainly not be so weak in itself as to collapse upon

the deflation of a single one of the central compartments. The incident

on the trip of the Zeppelin III to Berlin, in 1909, when the flying

blades of a broken propeller pierced the hull without causing an

accident, shows how much resistance it may offer.

¹ This is exactly what occured at the Chicago Meet, August 15, 1911,

when Badger’s Baldwin biplane collapsed at the end of a long dive,

causing the death of the aviator.

AMATEUR AVIATORS

It will probably come as a surprise to the average reader to learn that

at the end of 1910, there were more than a thousand amateur aviators in

this country, though all the flights which form the subject of newspaper

reports have been the work of not more than a dozen flyers and doubtless

half the population has not as yet seen an aeroplane in flight. The

desire to fly, whether it be to satisfy one’s desire to soar above the

world in seeming defiance of natural laws, or merely to obtain the

financial reward that is won by successful flight, attracts a great many

from all stations and walks of life. This is particularly true among

older boys who look on aviation as an advanced form of kite-flying. An

example of rather serious work along this line may be cited of two high

school boys of Chicago, Harold Turner and Fred Croll, who built a

monoplane weighing 125 pounds, Fig. 52. This machine, although too small

for a motor, was equipped with rudder and other operating planes and

levers, the elevating plane and ailerons being automatically operated by

an electrical device. On one of its flights the machine, carrying a 120

pound operator, was started and propelled by attaching it to an

automobile; it rose to a height of 15 feet, and remained in the air 43

seconds.

Contrary to all precedent, the average amateur is bent upon achieving

what the skilled professional considers as beyond even his talent and

resources—that of building his own flying machine. With every other

mechanical vehicle, the amateur learns to drive first and the majority

are content with that achievement—for example, very few chauffeurs have

any great ambition to build their own automobiles. With flying machines

(one of the most difficult of mechanical contrivances), nearly all

amateurs want to construct new types for themselves and all confidently

expect to fly with no more knowledge than that gained in constructing

them. We all have to be apprentices before becoming masters, so all

aviators necessarily have to be learners and "grass cutters" before

being professionals. Charles K. Hamilton was an exception, but he was

already an expert pilot of dirigible balloons, and he did not try to

build his own aeroplane. Willard, Mars, and Ely, all Curtiss pupils,

flew after a very short training, but they did not attempt to construct

aeroplanes for themselves. This is also true of Clifford B. Harmon, the

champion amateur.

[Illustration: Fig. 52. What an Amateur Aviator Can Do in Building an

Aeroplane]

*Classes of Amateurs*. _Inventors_. Generally speaking, amateurs are of

two classes. Those of the _first class_ believe they have conceived some

entirely new system or invention, or an improvement on some machine that

has previously proved a failure; they think they have discovered the

secret which other inventors who preceded them failed to grasp. They

expend their meager capital in trying to realize high hopes. A

comparatively small number ever get as far as completing the machine and

one trial on the field is usually sufficient to put a quietus on those

who do, as it is disappointing, to say the least, to see the result of a

number of months’ work undone in a twinkling without the machine having

shown the least disposition or ability to get off terra firma.

_Would Be Performers_. _The second class_ finds its chief incentive in

the munificent reward to be gained with what appears to be comparatively

little effort or expenditure, and the amateur who is seeking financial

returns has no alternative except to build his own machine, or enter

either the Wright or Curtiss school of flying and secure a berth with

one of these companies.

*Wright and Curtiss Patents*. This is the result of conditions at

present obtaining in the field of aviation. The only generally

successful types of American aeroplanes are the Wright and Curtiss, and

the acquirement of a biplane of either type means the expenditure of at

least $5,000 for the machine alone, and they are sold only to

individuals on the express condition that the machines are not to be

used for exhibition or as a means of profit to the owner. The

manufacturers have expert flyers of their own who attend meets and fairs

throughout the country. It would make their monopoly impossible to allow

outsiders to fly their aeroplanes publicly or to exhibit them. By this

restriction the price of the machines is kept up and large returns are

gained by exhibitions and flying.

To break this monopoly by importing European machines is not possible.

All the successful aeroplanes made abroad such as the Farman, Cody, and

Sommer biplanes; and the Bleriot, Antoinette, and Grade monoplanes are

fitted with devices of control or stability, or both, covered by the

Wright patents and can not be flown in this country without legal

trouble. The numerous foreign aviators who brought over their machines

in the fall of 1910 to compete at the International Meet, did so only on

being granted a concession by the Wright Company to the effect that they

would not be considered as infringers and sued. Similar arrangements

were made at subsequent meets and this handicap will always be present

where foreign machines are used.

_Evasion by Invention of New Types_. But when he thinks of the

unprecedented sums paid professionals for simply exhibiting their

machines and making short flights, the amateur is anxious to obtain a

share of the profits. No thought is given the fact that were he and all

his kind permitted to fly, the achievement would soon be commonplace and

the aviator’s golden age would be over. There are accordingly hundreds

of would-be aviators in this country today who are striving to evade the

Wright basic patents by either devising entirely new types of

aeroplanes, or by inventing new methods of control and stability that

will not infringe. Others, reasoning that the old aeroplanes built

before the advent of the Wright machine cannot be held as infringements

owing to priority, propose to develop Maxim, Langley, and Ader machines,

though the dictum in the New York Court of Appeals decision referred to

under the head of "Legal Status of Wright Patent," which states that a

prior machine which _had never been known to fly_ would not be

considered an anticipation of a modern successful machine, may prove a

stumbling block in their case as well. Thus, a round of the workshops of

these enthusiasts reveals a host of heavier-than-air machines of every

conceivable type and shape, every one of which, according to its

builder, is _an aeroplane that will fly_. Mineola and Garden City, Long

Island, harbor a score of these little shops the year round, but the

same scenes are being enacted on a smaller scale in almost every state

in the Union, and particularly in California, Ohio, Kansas,

Massachusetts, and Arizona, in addition to which there are many who are

carrying their experiments on in secret. Each believes deep in his heart

that he will succeed where a master failed.

"Maxim failed with this type of machine," quotes one. "How did he expect

to fly when his control was not proportionate to the machine’s lift

capacity?" Seemingly, nobody ever thought of that and our friend will

make a fortune by going Maxim one better, but he does not. After months

of labor and a great deal of expense he finds that some unforeseen

difficulty develops which keeps his machine to earth as if it were part

and parcel of it. Another has conceived a type of monoplane that is

entirely new—different from any existing type—and as the latter are all

foreign, he prides himself on having developed a monoplane that will be

entirely American—the first and only American monoplane. Theoretically,

it is a wonder; mechanically it is correct; and it speeds over the turf

with surprising velocity; but when the elevating rudder is operated to

make the machine rise, it balks and plunges head first into the ground.

Again and again, the propeller and other broken parts are replaced at no

small expense; again and again the inventor goes over every part of the

machinery and computes the dimensions of the supporting surface to see

if it all corresponds with the formula of his special theory. But time

after time, the aeroplane acts like a jumping frog and lands head first.

At last, its builder becomes convinced that there is something radically

wrong and begins to depart from his original plans, involving changes

that simply mean a waste of effort and money, since the inventor does

not himself know what he is trying to correct and no one else knows

better than he what the trouble is.

_Evasion by Acquiring European Types_. Others still, realizing from the

foregoing experiences that it is almost impossible to construct an

entirely new type of aeroplane off-hand, acquire European types and

propose to fit them with new control and stability devices, such as are

not covered by the Wright patents. So far, none has succeeded. Somehow,

the Wrights seem to have covered all the conceivable working devices for

control and stability, and the numerous attempts have accordingly

resulted in failure. Undoubtedly, some of these aeroplanes built by

amateurs may really be capable of flight; but how is the inventor to

know it when he lacks the ability to operate it? To know how to fly an

aeroplane is a condition precedent to success in the field of aviation

that can not be met by building of a machine. The beginner is thus badly

handicapped. Even though his machine may embody the elements essential

to successful flight, he may never be able to establish the fact, since

his first blundering attempt or two frequently ends by wrecking the

machine, and many have neither the means nor the stamina to persevere

further after a few bad wrecks, involving weeks and weeks of rebuilding

each time. He can not engage an expert to fly his machine for him, as

the expert’s time per minute figures out a price that makes him gasp,

and even at that the expert professional’s time is pretty much all

taken. Furthermore, very few would run the risk of attempting to fly an

untried aeroplane—they have more to lose through accidental injury than

the builder has through the failure of his theories.

And so it is with most inventors. They may have conceived something

really good, but it is not complete, and an aeroplane is hardly worth

its weight as junk unless it is. Hundreds of patents are taken out every

year on devices to be used on heavier-than-air machines; inventors by

scores make daily rounds trying to interest financiers in some seemingly

wonderful mechanical scheme, and dozens of companies are organized each

year to exploit some especially promising inventions. Numbers of

aeroplanes are constructed and hailed as marvels, but, somehow, when a

successful flight is made by an amateur it is always with some standard

aeroplane, either of the Curtiss or Farman types, and mostly the former.

In fact, the Curtiss has become a favorite with the amateur since the

Federal court refused to sustain the granting of a preliminary

injunction in favor of the Wright Company against Glenn H. Curtiss. It

is accordingly being taken for granted in general that the outcome of

the Wright vs. Curtiss litigation will be to declare the Curtiss machine

non-infringing. Should it be the other way about, there will certainly

be gloom and despair in the amateur camps throughout the country.

However, neither the Wrights nor Curtiss impose any restriction upon the

building of machines of their types for experimental purposes, so that

the amateur who wishes to copy them may safely do so, provided no

attempt be made to employ the machine for purposes of public exhibition

or financial gain.

EXAMINATION PAPER

BUILDING AND FLYING AN

AEROPLANE

*PART II*

*Read Carefully*: Place your name and full address at the head of the

paper. Any cheap, light paper like the sample previously sent you may be

used. Do not crowd your work, but arrange it neatly and legibly. _Do not

copy the answers from the Instruction Paper; use your own words so that

we may be sure that you understand the subject_.

1. Contrast the Bleriot with the Curtiss in every essential

particular.

2. Give details of the Bleriot running gear.

3. How is the supporting plane of the Bleriot built and reinforced?

4. What sort of fabric is used to cover the plane and how is it

fastened on?

5. Describe by sketch the Bleriot control system.

6. How does the location of the motor in the Bleriot compare with its

location in the Curtiss?

7. What is “grass-cutting” and why is it practiced?

8. Describe some of the devices used in aviation schools.

9. How is the elevating plane manipulated to start the aeroplane from

the ground?

10. How is the static balance of a machine determined?

11. How does warping the wings affect the behavior of an aeroplane?

How should this be practiced?

12. Give the process of making a turn in an aeroplane.

13. What is “banking”? What must be done to prevent excessive banking

on a turn?

14. How can a turn be made in a wind?

15. Why should the start and the landing always be made in the teeth

of the wind?

16. What is the attitude of the masters of aviation toward fancy

flying?

17. Classify the most common sources of accidents.

18. What must an aviator do in case his motor stops in midair? Is this

considered a dangerous situation?

19. What are the relative merits of biplane and monoplane as regards

the avoidance of accidents?

20. What are some of the devices used to protect the aviator in case

his machine collapses?

21. Analyze rather carefully the additional stresses put upon an

aeroplane when an aviator suddenly swoops and then rights his

machine by a quick movement of the control.

*After completing the work, add and sign the following statement:*

I hereby certify that the above work is entirely my own.

(Signed)