The Wright Flyer and its Possible Uses in War
Lieutenant F. E. Humphreys, Corps of Engineers
One Airman's View of the Future
Dr. Richard P. Hallion
At the dawn of aviation, many wondered what the future of flight—and
the value of aircraft—might be. One such individual was Lieutenant Frederick
Erastus Humphreys, an engineering officer and West Point graduate (Class of
1906, 8th out of 78 cadets who graduated as commissioned officers). He became
interested in aviation while attending the Army’s Engineer School. Humphreys
was the first American military pilot; though he left military service as a
regular officer in 1910, he subsequently served with distinction in the New
York National Guard, and then in the Army Air Service during the First World
War. He retired in ill-health as a Brigadier General from the New York National
Guard in 1939, and died in January 1941 at the age of 57. The following is a
reprint of an essay he wrote on the future of flight, which appeared in the
March-April 1910 issue of the Journal of the United States Artillery, pp. 144-147.
(References to illustrations in the original article have been removed). His
discussion involves the 1909 Signal Corps Flyer, S.C. 1, as modified at Ft.
Sam Houston by Lt. Benjamin Foulois to have the upper canard elevator surface
removed and replaced behind the horizontal tail as a “fixed” horizontal
stabilizer. From a vantage point of almost a century, this essay offers both
a practical introduction to the Wright military flyers, as well as a sometimes
quaint and amusing look at then-contemporary military aviation and how it might
The Wright Flyer and its Possible Uses in War
Lieutenant F. E. Humphreys, Corps of Engineers
This article originally appeared in the Journal of the United States Artillery
(v. 33, n.2, Mar-Apr 1910).
Flying consists in sustaining a body in the air against the force of gravity
by means of the dynamic action of the air against some movement of the body.
Men have attempted to fly in three different types of machine, the ornithopter,
which flaps its wings in imitation of the flight of birds; the helicopter, which
lifts itself by the use of vertical propellers, and the so-called aeroplane,
which is sustained by the reaction of the air on inclined surfaces.
Neither the ornithopter nor the helicopter has given practical results. The
aeroplane is the one which has made all the flights worth mentioning and is
at all practical.
The word “aeroplane” is decidedly a wrong name to apply to the present
day machine, as the surfaces used are not planes but curved surfaces. The Wright
brothers and several New York papers have introduced the use of the word “flyer,” which is much more appropriate.
The Wright flyer which has been purchased by the Army for instruction and experimentation
consists of two main surfaces, a forward elevating plane, a steadying plane
in rear and two vertical rudders for steering.
The main surfaces do the actual supporting of the flyer. They are about 36 feet
long, 5.2 feet deep, superposed with 5.2 feet between the surfaces. These, like
the main surfaces in other successful machines, are concaved downward [e.g.
have an airfoil cross-section—ed.].
The forward plane [canard elevator--ed.] is used for elevating and depressing
the flyer. It is about 15 feet long and 3 feet wide, arranged so that it is
concaved on whichever surface is bearing [that is, referring to whether it is
pivoted with a nose-up positive angle of attack for inducing a climb, or a nose-down
negative angle of attack for inducing a dive—ed.].
The steadying plane [the fixed horizontal stabilizer located aft of the rudder—ed.]
is of the same form as the front elevating plane, but is rigidly attached and
has no motion. This plane was at first used superimposed on the front plane
and having the same motion, but was changed to the rear to give greater steadiness
[e.g. positive longitudinal stability—ed.]
The vertical rudders are two planes, each about 1 ½ by 6 feet, placed
1 ½ feet apart and 8 feet behind the main surfaces. They guide the flyer
in the air in the same manner that a rudder guides a ship in the water.
To secure lateral stability the tips of the main surfaces can be warped. This
idea was first used by the Wrights and is one of their patents, but it is now
used by several foreign aviators, notably Bleriot and the Antoinette Company.
The lawsuit of the Wrights against the Sydney Bowman Automobile Company when
they imported a Bleriot machine to sell in this country was over this point.
The main surfaces are in three parts, a main central section and two wing tips.
The central section is 13 feet long and each tip 11 ½ feet long. There
are between these sections joints movable in a vertical section. The entire
front of the main surfaces is trussed by wooden struts and steel wires and is
immovable. The middle section is similarly trussed in rear and also cross-trussed
from front to rear. The end sections, however, are trussed in rear [e.g., the
outer wing panels were not rigidly trussed fore-and-aft, thus enabling them
to be flexed—that is, “warped”—ed.].
From this it is seen that if the lower wire is pulled toward the left the right
tip will be pulled down and the left up, and vice-versa. Then, as the front
of the surfaces is immovable, a movement of the wire in any direction will warp
the tips and cause them to present a greater angle on one side and a lesser
on the other side, thus giving an increased lift of the side of the greater
angle and a diminished lift on the other side.
(For small angles the greater the angle the greater the lift. The exact law
of this lift, like all other aero-dynamic data, is in dispute, as all the data
comes from men who have not built successful machines, and the men who have
built successful machines either say nothing or imply that the existing law
tables are not correct.)
The flyer is given motion by two propellers about 9 feet in diameter and 11-foot
pitch, which revolve in opposite directions at about 350 revolutions per minute.
[Note that (350 rpm x 11 ft) = 3,850 ft./min.; (3,850 ft./min. x 60 min./hr.)
= 231,000 ft./hr.; (231,000 ft./hr. ÷ 5,280 ft/mile) = 43.75 mph—ed.]
They are driven by chains from the engine.
The engine is gasoline, four cylinder, water cooled, running at about 1,200
revolutions per minute and giving about 36 horsepower at that speed. It weighs
165 pounds, exclusive of radiator and magneto.
The flyer altogether when leaving the rail [e.g., the launching catapult’s
monorail—ed.] with water, gasoline and two men weighs about 1,100 pounds;
it goes at a rate of about 40 miles per hour and carries enough fuel for a flight
of three and a half hours.
There are several questions which are almost invariably asked by people looking
over the machine. One of them is: ‘What happens when your motor stops?
Do you have to come down?’
A flyer is only sustained in the air by the reaction due to its speed, and whenever
this is lost the flyer will drop. However, this is never totally lost, as the
same force that causes the descent can be used as a motive power to keep up
the speed. In other words, if the motor stops, the machine is pointed down at
an angle until the component of gravity in the direction it is going is equal
to the push required. This keeps up the speed necessary for control, but, of
course, makes the flyer gradually descend.
The present flyer can glide down without motor at an angle of from 1 in 5 to
1 in 7.
The next question is: ‘What use are these things going to be?’
From a military standpoint, the first and probably the greatest use will be
found in reconnaissance. A flyer carrying two men can rise in the air out of
range of the enemy, and, passing over his head out of effective range, can make
a complete reconnaissance and return, bringing more valuable information than
could possibly be secured by a reconnaissance in force. This method would endanger
the lives of but two men; the other would detach several thousand men for a
length of time and endanger the lives of all.
The next use will probably be in carrying messages. A flyer will average a speed
of 40 miles an hour in a straight line. Excepting the telephone and the telegraph,
there is no other method of communication as rapid as flying. Automobiles, motor
cycles, etc., usually do not average this speed, and very often have to go around
two or three sides of a square to get where to they are going. This would be
particularly valuable for carrying messages between bodies which have been more
or less separated, as between the main attack and a flank attack, and between
the main body and independent cavalry or cavalry on a raid.
Another time where advantage might be taken of the speed of these machines is
when officers of high rank might desire to give personal supervision at a distant
point of the line or to go form one point to another for a council of war. This
is particularly the case in modern armies of large size where the front is 70
or 80 miles long. Take an army on a 70-mile front, the army consisting of three
parts, the center and the flanks. The commanding officer desires a council of
war. The two flank commanders are then about 20 to 25 miles from main headquarters.
These men could be brought to the council in three-fourths of an hour by a flyer
and returned in about the same time. If they tried to come in an automobile,
or on horseback, they might find no good roads, and what there were would probably
not be straight and would be certain to be congested. Their progress then would
almost certainly be slow, and they would probably be kept from their commands
As the United States was the only first-class power which signed the Hague agreement
as to dropping projectiles form balloons, it is not probable that this agreement
will be in force in future wars. Probably a large amount of damage could be
done to the personnel of the enemy when in mass, or in a raid to the storehouses
and depot, by projectiles dropped from a flyer. That any could be done to fortifications
or ships is doubtful.
Flyers might also be used to give warning to war vessels and fleets of an impending
attack by submarines. A person looking at water can see down into it only when
the angle of the line of sight with the vertical is less than about 50 degrees.
In other words, a man at a masthead 100 feet high could not see a submarine
until it was about 125 feet away; a man in a flyer 3,000 feet directly over
a ship could see a submarine approaching within a radius of 4,000 feet of the
vessel and by circling around could greatly extend the zone of protection.
Another remark frequently made is: “Well, I don’t see what use these
things are if you can’t fly except in a large open plain and in a calm
or almost a calm.”
This is quite reasonable, judging from the flights at Fort Myer and College
Park. However, conditions at both places were quite different from those of
At Fort Myer, Orville Wright had a new machine 4 feet less in width and 9 inches
less in breadth than usual [that is, the S.C. 1 as originally configured—ed.].
He, naturally, did not want to try this machine in anything except a calm, and
he waited until the weather conditions were favorable for trying it. When used
to the machine, he went up in winds up to 15 miles per hour, but never more
than this. His object was to go through the tests and sell his machine to the
Government, and he did not care to run any risk of smashing the machine beforehand.
At College Park the object of Wilbur Wright was to instruct two officers in
handling the machine. These men had to receive their instruction in a calm and
gradually advance to higher wind. To have taken the machine out in high winds
would not have been any instruction to the officers and would have risked smashing
the machine and having it put out of commission during weather favorable for
In the hands of experts these machines ought to be able to work in winds up
to 35 miles per hour and would be able to work in fields much smaller than College
Of course, accidents of one kind or another are bound to occur, and in open
country the damage resulting form any cause, such as the engine stopping or
a wire breaking, is greatly decreased. In flying over rough country, any accident
is liable to cause serious consequences, especially if the flyer is low down,
as it may not be able to avoid trees, houses, trolley wires, telegraph poles,
etc. At a great height this risk lessens, as there is then a much larger radius
from which to select a landing place.
Of course, in time of war flyers would cross any kind of country, but in their
present state of development there is no more reason for risking the lives of
aviators by sending them over rough ground unnecessarily than for risking those
of soldiers by firing real projectiles at maneuvers.
In addition, it must be remember that if because of a storm the flyers can
not be used the Army is no worse off than if it had none, and the cost and number
of men used is insignificant. One officer, ten men and two wagons are a full
equipment for a flyer.
It is shown in its original configuration as a pure canard, with a biplane
forward elevator. During subsequent operational testing at Ft. Sam Houston,
Texas, the top surface of this elevator was later removed and placed aft of
the vertical fins as a fixed horizontal stabilizer.
New York State Division of Military and Naval Affairs: Military History
September 19, 2007