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Appndix C
The 1914 Tests Of The Langley "Aerodrome"1
BY C.G. ABBOT,
SECRETARY, SMITHSONIAN INSTITUTION
NOTE-This paper has been submitted to Dr. Orville Wright, and under
date of October 8, 1942, he states that the paper as now prepared will
be acceptable to him if given adequate publication.
It is everywhere acknowledged that the Wright brothers were the first
to make sustained flights in a heavier-than-air machine at Kitty Hawk,
North Carolina, on December 17, 1903.
Mainly because of acts and statements of former officers of the
Smithsonian Institution, arising from tests made with the reconditioned
Langley plane of 1903 at Hammondsport, New York, in 1914, Dr. Orville
Wright feels that the Institution adopted an unfair and injurious
attitude. He therefore sent the original Wright Kitty Hawk plane to
England in 1928. The nature of the acts and statements referred to are
as follows:
In March 1914, Secretary Walcott contracted with Glenn H. Curtiss to
attempt a flight with the Langley machine. This action seems ill
considered and open to criticism. For in January 1914, the United States
Court of Appeals, Second Circuit, had handed down a decision recognizing
the Wrights as "pioneers in the practical art of flying with
heavier-than-air machines" and pronouncing Glenn H. Curtiss an infringer
of their patent. Hence, in view of probable further litigation, the
Wrights stood to lose in fame and revenue and Curtiss stood to gain
pecuniarily, should the experiments at Hammondsport indicate that
Langley's plane was capable of sustained flight in 1903, previous to the
successful flights made December 17, 1903, by the Wrights at Kitty Hawk,
N.C.
The machine was shipped to Curtiss at Hammondsport, N.Y., in April.
Dr. Zahm, the Recorder of the Langley Aerodynamical Laboratory and
expert witness for Curtiss in the patent litigation, was at Hammondsport
as official representative of the Smithsonian Institution during the
time the machine was being reconstructed and tested. In the
reconstruction the machine was changed from what it was in 1903 in a
number of particulars as given in Dr. Wright's list of differences which
appears later in this paper. On the 28th of May and the 2d of June,
1914, attempts to fly were made. After acquiring speed by running on
hydroplane floats on the surface of Lake Keuka the machine lifted into
the air several different times. The longest time off the water with the
Langley motor was approximately five seconds. Dr. Zahm stated that "it
was apparent that owing to the great weight which had been given to the
structure by adding the floats it was necessary to increase the
propeller thrust." So no further attempts were made to fly with the
Langley 52 HP engine.
It is to be regretted that the Institution published statements
repeatedly2 to the effect that these experiments of 1914
demonstrated that Langley's plane of 1903 without essential modification
was the first heavier-than-air machine capable of maintaining sustained
human flight.
As first exhibited in the United States National Museum, January 15,
1918, the restored Langley plane of 1903 bore the following label:
THE ORIGINAL, FULL-SIZE
LANGLEY FLYING MACHINE, 1903
For this simple label others were later substituted containing the
claim that Langley's machine "was the first man-carrying aeroplane in
the history of the world capable of sustained free flight."
Though the matter of the label is not now an issue, it seems only
fair to the Institution to say that in September 1928, Secretary Abbot
finally caused the label of the Langley machine to be changed to read
simply as follows:
LANGLEY AERODROME
THE ORIGINAL SAMUEL PIERPONT LANGLEY
FLYING MACHINE OF 1903, RESTORED.
Deposited by
the Smithsonian Institution
301,613
This change has frequently been overlooked by writers on the
controversy.
In January 1942, Mr. Fred C. Kelly, of Peninsula, Ohio, communicated
to me a list of differences between the Langley plane as tested in 1914
and as tested in 1903, which he had received from Dr. Wright. This list
is given verbatim below. The institution accepts Dr. Wright's statement
as correct in point of facts. Inferences from the comparisons are
primarily the province of interested experts and are not discussed
here.
COMPARISON OF THE LANGLEY MACHINE OF 1903 WITH THE
HAMMONDSPORT MACHINE OF MAY-JUNE, 1914
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*The letters L.M. in the first column refer to Langley Memoir.
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WINGS
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| LANGLEY, 1903 |
HAMMONDSPORT, 1914 |
| 1. SIZE: 11' 6"X 22' 6" (L.M.*p.206) |
SIZE: 10' 11 ?" X 22' 6" |
| 2. AREA: 1040 sq. ft (L.M. p.206) |
AREA: 988 sq. ft. |
| 3. ASPECT RATIO: 1.96 |
ASPECT RATIO: 2.05 |
| 4. CAMBER: 1/12 (L.M. p. 205) |
CAMBER: 1/18 |
| 5. LEADING EDGE: Wire 1/16"
diameter L.M. Pl.66) |
LEADING EDGE: Cylindrical spar 1
?" dia. at inner end, tapering to 1"
dia. at outer end. |
| 6. COVERING: Cotton fabric, not
varnished. |
COVERING: Cotton fabric, varnished. |
| 7. CENTER SPAR: Cylindrical
wooden spar, measuring 1 ?" dia.
For half its length and tapering to
1" at its tip. (L.M. p. 204) Located
on upper side of wing. |
CENTER SPAR: Cylindrical spar
about 1 ?" dia. at inner end, tapering
to about 1" dia. at outer end. Located
on upper side of wing. This center
spar was reinforced (1) by an extra
wooden member on the underside of
the wing, which measured 1" X 1 ?"
and extended to the 7th rib from the
center of the machine; and (2) by
another wooden reinforcement on
the underside extending out about
one-fourth of the length of the wing. |
| 8. RIBS: Hollow box construction.
(L.M. Plates 66, 67. |
RIBS: Most of the original Langley
box ribs were replaced with others
made at Hammondsport. (Manly letter,
1914.) The Hammondsport ribs
were of solid construction and made
of laminated wood. That part of the
rib in front of the forward spar was
entirely omitted. |
| 9. LOWER GUY-POSTS: A single
round wooden post for each pair
of wings (see Fig. 3), 1 ?" in dia. 6
?' long. (L.M. Plate 62, p.184.) |
LOWER GUY-POSTS: Four for each
pair of wings (see Fig.4), two of which
were of streamline form measuring 1
?" X 3 ?" X 54" long; and two measuring
2" X 2" with rounded corners, 3'
9" long. |
| 10.The front wing guy-post was
located 28 ?" in front of the main
center spar (L.M. Plate 53.) |
The front-wing guy-posts were located
directly underneath the main center
spar, 28 ?" further rearward than in
1903. |
| 11. The rear wing guy-post was located
31 ?" in front of the main center
spar. (L.M. Plate 53.) |
The rear wing guy-posts were located
directly under the main center spar,
31 ?" further rearward than in 1903. |
| 12.UPPER GUY-POSTS: For each pair
of wings a single steel tube ?" dia.,
43" long. (L.M. p. 184, pl. 62.) |
UPPER GUY-POSTS: For each pair of
wings, two streamline wooden posts
each 1 ?" X 3 ?", 76" long, forming an
inverted V. (see Fig. 4.) |
| 13. Front wing upper guy-post located
28 ?" in front of the main center
spar. (L.M. pl. 53.) |
Front wing upper guy-posts located
directly over main spar, 28 ?" further
rearward than in 1903. |
| 14. The rear wing upper guy-post was
located 31 ?" in front of the main
center spar. (L.M. pl. 53.) |
The rear wing guy-posts were located
directly over the main center spar, 31
?" further rearward than in 1903. |
| 15. TRUSSING: The wing trussing
wires were attached to the spars
at the 5th, 7th, and 9th ribs out
from the center (L.M. pl. 54.)
The angles between these wires
and the spars to which they were
attached are shown in Fig.3. |
TRUSSING: A different system of
wing trussing was used, and the wing
trussing wires were attached to the
spars at the 3rd, 6th and 9th ribs
from the center. The angles between
these wires and the spars to which
they were attached were all different
from those in the original Langley
machine. (See Fig. 4.) |
CONTROL SURFACES
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| LANGLEY, 1903 |
HAMMONDSPORT, 1914 |
| 16. VANE RUDDER: A split vane composed
of two surfaces united at their
leading edges and separated 15" at
their trailing edges, thus forming a
wedge. Each surface measured 2' 3"
X 4' 6", with aspect ratio .5. (L.M. p.
214, pls. 53, 54.) |
VERTICAL RUDDER: The Langley
vane rudder was replaced by a single
plane rudder which measured 3' 6" X
5', with aspect ratio of .7. |
| 17. Operated by means of a wheel
located slightly in front of the pilot at
his right side and at the height of his
shoulder (L.M. p. 216, pls. 53, 54.) |
Operated at Hammondsport through
the Curtiss steering wheel in some
tests (Zahm affidavit pp. 5, 6),
through the Curtiss shoulder yoke in
some others (Manly letter, 1914), and
fixed so as not to be operable at all in
still others (Zahm affidavit p.7). |
| 18. Used for steering only. (L.M. p.
214.) |
Used "as a vertical aileron to control
the lateral poise of the machine"
(Zahm affidavit p. 6), as well as for
steering (Zahm affidavit p. 7). |
| 19. PENAUD TAIL: This was a dartshaped
tail having a vertical and a
horizontal surface (Penaud tail), each
measuring 95 sq. ft. It was located in
the rear of the main frame. |
TAIL RUDDER: Same size and construction
as in 1903. |
| 20. Attached to a bracket extending
below the main frame. |
Attached to same bracket at a point
about 8" higher than in 1903. |
| 21. "Normally inactive," (L.M. p. 216)
but adjustable about a transverse horizontal
axis by means of a self-locking
wheel located at the right side of the
pilot, even with his back, and at the
height of his shoulder. (L.M. pls. 51,
53.) |
Operable about a transverse horizontal
axis and connected to a regular
Curtiss elevator control post directly
in front of the pilot (Zahm affidavit p.
5). |
| 22. Immovable about a vertical axis.
(L.M. p. 214, pl. 56, Fig. 1.) No
means were provided for adjusting
this rudder about a vertical axis in
flight. "Although it was necessary
that the large aerodrome should be
capable of being steered in a horizontal
direction, it was felt to be unwise
to give the Penaud tail and rudder
motion in the horizontal plane in
order to attain this end." (L.M. p.
214) |
Immovable about a vertical axis on
May 28, 1914, only. Thereafter it was
made movable about a vertical axis
and was connected through cables to
a Curtiss steering wheel mounted on
a Curtiss control post directly in front
of the pilot. |
| 23. KEEL: A fixed vertical surface
underneath the main frame measuring
3' 2" in height by 6' average
length. Area 19 sq. ft. (L.M. pl. 53.) |
KEEL: Entirely omitted. |
SYSTEM OF CONTROL
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| LANGLEY, 1903 |
HAMMONDSPORT, 1914 |
| 24. LATERAL STABILITY: The dihedral
only was used for maintaining
lateral balance. (L.M. p. 45.) |
LATERAL STABILITY: Three means
were used for securing lateral balance
at Hammondsport: The dihedral
angle as used by Langley, a rudder
which "serves as a vertical aileron"
(Zahm affidavit p. 6), and the Penaud
tail rudder. The last two constituted a
system "identical in principal with
that of Complainant's [Wright] combined
warping of the wings and the
use of the vertical rudder." (Zahm
affidavit p.6) |
| 25. LONGITUDINAL STABILITY:
Langley relied upon the Penaud system
of inherent stability for maintaining
the longitudinal equilibrium. "For
the preservation of the equilibrium
[longitudinal] of the aerodrome,
though the aviator might assist by
such slight movements as he was able
to make in the limited space of the
aviator's car, the main reliance was
upon the Penaud tail." (L.M. p. 215.) |
LONGITUDINAL STABILITY: At
Hammondsport the Penaud inherent
longitudinal stability was supplemented
with an elevator system of
control. |
| 26. STEERING: Steering in the horizontal
plane was done entirely by the
split-vane steering rudder located
underneath the main frame. (L.M. p.
214.) |
STEERING: On one day, May 28,
1914, steering in the horizontal plane
was done with the vertical rudder
which had been substituted for the
original Langley split-vane steering
rudder. After May 28th the steering
was done by the vertical surface of the
tail rudder (Zahm affidavit p. 7),
which in 1903 was immovable about a
vertical axis (L.M. p. 214.) |
POWER PLANT
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| LANGLEY, 1903 |
HAMMONDSPORT, 1914 |
| 27. MOTOR: Langley 5 cylinder
radial. |
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| 28. IGNITION: Jump spark with dry
cell batteries. (L.M. p. 262.) |
IGNITION: Jump spark with magneto. |
| 29. CARBURETOR: Balzer carburetor
consisting of a chamber filled with
lumps of porous cellular wood saturated
with gasoline. The air was
drawn through this wood. There was
no float feed. (L.M. p. 225.) |
CARBURETOR: Automobile type
with float feed. |
| 30. RADIATOR: Tubes with radiating
fins. |
RADIATOR: Automobile radiator of
honeycomb type. |
| 31. PROPELLERS: Langley propellers
(L.M. pl. 53, pp. 178-182). MOTOR:
Langley motor modified. |
PROPELLERS: Langley propellers
modified "after fashion of early
Wright blades." |
LAUNCHING AND FLOATS
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| LANGLEY, 1903 |
HAMMONDSPORT, 1914 |
| 32. LAUNCHING: Catapult mounted
on a houseboat. |
LAUNCHING: Hydroplanes, developed
1909-1914, attached to the
machine. |
| 3. FLOATS: Five cylindrical tin floats,
with conical ends, attached to underside
of main frame at appropriate
points, and about six feet above lowest
part of machine. |
FLOATS: Two wooden hydroplane
floats, mounted beneath and about 6
feet to either side of the center of the
machine at the lateral extremities of
the Pratt system of trussing used for
bracing the wing spars of the forward
wings; and one (part of the time two)
tin cylindrical floats with conical
ends, similar to but larger than the
Langley floats, mounted at the center
of the Pratt system of trussing used
for bracing the rear wings. All of the
floats were mounted from four to five
feet lower than the floats of the original
Langley, thus keeping the entire
machine above the water. |
WEIGHT
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| LANGLEY, 1903 |
HAMMONDSPORT, 1914 |
| 34. TOTAL WEIGHT: With pilot 850
pounds (L.M. p. 256). |
TOTAL WEIGHT: With pilot, 1170
pounds. |
| 35. CENTER GRAVITY: 3/8" above
line of thrust. |
CENTER GRAVITY: About one foot
below line of thrust. |
Since I became Secretary, in 1928, I have made many efforts to
compose the Smithsonian-Wright controversy, which I inherited. I will
now, speaking for the Smithsonian Institution, make the following
statement in an attempt to correct as far as now possible acts and
assertions of former Smithsonian officials that may have been misleading
or are held to be detrimental to the Wrights.
1. I sincerely regret that the Institution employed to make the tests
of 1914 an agent who had been an unsuccessful defendant in patent
litigation brought against him by the Wrights.
2. I sincerely regret that statements were repeatedly made by
officers of the Institution that the Langley machine was flown in 1914
"with certain changes of the machine necessary to use pontoons," without
mentioning the other changes included on Dr. Wright's list.
3. I point out that Assistant Secretary Rathbun was misinformed when
he stated that the Langley machine "without modification" made
"successful flights."
4. I sincerely regret the public statement by officers of the
Institution that "The tests (of 1914) showed that the late Secretary
Langley had succeeded in building the first aeroplane capable of
sustained free flight with a man."
5. Leaving to experts to formulate the conclusions arising from the
1914 tests as a whole, in view of all the facts, I repeat in substance,
but with amendments, what I have already published in Smithsonian
Scientific Series, Vol 12-1932, page 227: The flights of the Langley
aerodrome at Hammondsport in 1914, having been made long after flying
had become a common art, and with changes of the machine indicated by
Dr. Wright's comparison, as given above, did not warrant the statements
published by the Smithsonian Institution that these tests proved that
the large Langley machine of 1903 was capable of sustained flight
carrying a man.
6. If the publication of this paper should clear the way for Dr.
Wright to bring back to America the Kitty Hawk machine to which all the
world awards first place, it will be a source of profound and enduring
gratification to his countrymen everywhere. Should he decide to deposit
the plane in the United States National Museum, it would be given the
highest place of honor, which is its due.
Publication of this statement in the Smithsonian Annual Report marked
the end of the long controversy.
Orville Wright died January 30, 1948. He had notified the Science
Museum at South Kensington, England, that he wished to have the original
1903 plane returned to the United States. Toward the end of 1948 it was
brought back and deposited by the Wright executors in the National
Museum, administered by the Smithsonian Institution. It was formally
dedicated on December 17, the forty-fifth anniversary of the first
flight.
1For an account of early Langley and Wright aeronautical
investigations, see Smithsonian Report for 1900 and The Century Magazine
of September 1908.
2Smithsonian Reports: 1914, pp. 9, 219, 221, 222; 1915,
pp. 14, 121; 1917, p. 4; 1918, pp. 3, 28, 114, 166. Report of U.S.
National Museum, 1914, pp. 46 and 47.
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