Flight, October 1921

THE LANGLEY MACHINE AND THE HAMMONDSPORT TRIALS

   UNDER the above title Mr. Griffith Brewer read a paper before the Royal Aeronautical Society on October 20, in which he traverses the now generally accepted claim that the Langley machine of 1903 has been flown. He maintains it never has been flown or ever could fly. Mr. Brewer's contention is that the machine was so weak structurally, and of so bad design, that it could not possibly have flown in its original state, and in his paper he alleges that the machine was so altered for the flight tests made by Glenn Curtiss as to be virtually a different machine. We have not the space to publish Mr. Griffith Brewer's paper in full, but the following brief summary, and some of the illustrations from the paper, will serve to show the main points of the lecturer's contentions. There is little doubt that the paper will cause Something of a sensation in America, where the question “Langley or Wright Brothers,” had caused much more controversy than it has on this side.
   In the openin paragraphs of his paper Mr. Brewer refers to some remarks made by Lord Northcliffe during the discussion on the Wilbur Wright Memorial Lecture given by Mr Brewer in 1916 in which Lord Northcliffe stated that he has firmly convinced that the credit of the first flying machine is due to the Wright brothers, and from the point of practical flying to nobody else. Mr. Brewer said that he had recently returned from further investigations in America, and that as a result of these he was now in a position to report to the Royal Aeronautical Society that the reports of the Hammondsport trials in 1914 are inaccurate as recorded at the Smithsonian Institution.
   The lecturer then referred to the early history of the Wright brothers and of Langley, pointing out that they had been carrying on their investigations independently hundreds of miles apart, and had both approached the final stage of their independent experiments at the same time, Langley tested his machine a few weeks before the Wrights were ready to test theirs, and the attempts to fly the Langley machine failed. The Wrights, one week after Langley's second attempt, tested theirs and succeeded. Mr. Brewer stated that the Smithsonian Institution has always attributed the failure of the Langley machine in 1903 to a failure in the launching apparatus, and that is has hitherto been generally accepted that the machine was wrecked without having had a fair opportunity of proving whether it was capable of flight. He then proceeded to show how the Hammondsport machine was altered to enable it to fly, and showed slides illustrating the machine getting off the top of the houseboat, which, he claimed, showed how the wings of the original machine twisted under load. He also stated that this twisting was the probable cause of the failure of the machine to fly rather than any defect in the launching apparatus.
   Figs. 1 and 2 are side elevations of the original Langley machine of 1903 and the Hammondsport machine of 1914, prepared by Mr. Brewer. In Figs. 3 and 4 the wing trussing of the same machines is indicated. The differences will be clear to readers of this journal without further comment. Mr. Brewer's claims are, in the main, that the alterations were so extensive and of such a nature that the machine could not justly be called the same as the original Langley of 1903.
   The lecturer then described some of the early trials with the Langley, pointing out that during the time immediately following the tests there was no mention of any failure on the part of the launching gear. He called attention to the placing of the wing trusses and guy posts, G (Fig. 1), which were, he stated, 28 per cent, of the chord back from the leading edge. His contention is that, once the machine had left the launching apparatus, the centre of pressure would be behind the position of the king-posts, or at about 37 per cent, of the chord. As a result of this the wing would tend to twist, and by way of proof that this actually happened, Mr. Brewer showed slides of photographs taken immediately after the launch. We reproduce one of these photographs herewith, which certainly appears to substantiate Mr. Brewer's claim. The front wing is obviously twisted, its trailing edge bearing against the propeller framework. The effect of this distortion would naturally be to cause the machine to dive, and it is to this distortion that Mr. Brewer attributes the failure of the machine to fly, not to any fault in the launching apparatus. Several of the slides shown illustrated the bending back of the lower king-post G in such a manner as to indicate a very considerable twisting of the wing, such as might be caused by the c.p. being too far behind the wing trusses.
   As regards the changes made in the Hammondsport machine, Mr. Brewer enumerated these very thoroughly. We have not the space here to publish all of them, but they may be briefly summarised as follows: New wings were constructed in which the portion of the wing in front of the front spar was omitted. This reduced the camber from about 1 in 12 to about 1 in 18. It reduced the wing area and changed the aspect ratio. The top guy post was replaced by a much taller inverted V, and the lower guy post by four much heavier posts. The guy wires at Hammondsport were attached to the spars at different points from those in the Langley machine. The whole system of trussing was moved 30 inches farther back, so as to be near the normal centre of pressure of the wings. The middle spar of each wing was strengthened by an additional spar underneath the ribs and extending outwards for about two-thirds of the length of the spar. The wings were further strengthened by the under truss work, GGGG and E1E1 (Fig. 4), diagonally braced, rigidly supporting the wings to about a quarter of their length out from the central frame. The ribs of the Hammondsport machine were heavier and stronger than those of the Langley. Floats, unknown in the day of Langley, were substituted for the original launching gear. The large fixed keel vertical surface (K in Fig. 1) was omitted, and the small split vane steering rudder was replaced by a single rudder (V, Fig. 2) of larger area. Further, the divided rudder of the Langley was intended to steer the machine, while the rudder in the Hammondsport machine was connected up to a hand wheel or to the Curtiss yoke, which was the standard Curtiss system of lateral control at the time.
   The rudder V of the Hammondsport machine was not, therefore, intended for steering but for lateral control. The tail of the Langley machine was adjustable up and down by a self-locking hand wheel, while in the Hammondsport it was coupled to a regular Curtiss steering post. The original carburettor was changed for one of modern type. The tail of the Langley was adjustable up and down only, and not about a vertical axis. In the Hammondsport machine it was connected to a regular Curtiss steering wheel.
   Mr. Brewer contends that: The Langley machine was not capable of sustained flight and that the inscription on the Langley machine in the Smithsonian Institution at Washington should be changed to accord with facts.