Langley: the forgotten man in aviation history

Press, 11 June 1982, Page 18

Langley: the forgotten man in aviation history

By

OLIVER RIDDELL

Arguments about who first flew a manned heavier-than-air craft, the Wright Brothers at Kitlyhawk in the United States or Richard Pearse at Temuka in New Zealand, have tended to overshadow public recognition of their precursors. But it was no accident or coincidence that in the early years of the twentieth century such an event occurred. The success of the Wright Brothers and Pearse owed a great deal to the work of the secretary of the Smithsonian Institution in the United States (Professor S. P. Langley). Yet much of his work with heavier-than-air craft has been forgotten, or at best neglected, outside the United States and also outside a narrow group of enthusiasts interested in early aviation. It is too much to say that Professor bangley invented the heavier-than-air craft, but the achievements of the Wright Brothers were directly based on his work. So the appearance for sale at an antiquarian bookshop in Wellington of a bound volume of the '•Strand” magazine of 1897 has aroused considerable interest. In it Langley sets out for the layman a detailed account of his work and achievements. Langley was prompted into writing this article by his fellow inventor, Alexander Graham Bell, of telephone fame. Bell witnessed the historic flight of Langley's craft in May, 1896, and took a photograph of it. Although Langley was fascinated all his life by the mechanics of flight, it was not until his old age that he made a serious study of it. He discarded the learned wisdom of how birds flew, and of how lighter-than-air craft such as balloons flew. Instead, he studied the problems logically and specifically as they would apply to heavier-than-air flight. First was the problem of velocity. Recent developments in the internal combustion engine gave some promise here, but the engine had to be light and powerful, which the engines of the day were not. Velocity had to be maintained without tearing the machine to pieces.

Second was the problem of balance. The craft would not be able to manoeuvre in response to circumstances, as a bird could. So its component parts had to be so distributed that they were in a state of equilibrium consistent with the velocity, or it would fall to pieces or fall to the ground. Third was the problem of manoeuvre itself. The craft had to be able to turn, rise and fall, consistent with orderly flight and to meet the demands of air speed and wind current. Years of trial and error went into the craft. Langley almost lost count of his failures. Then, on May 6, 1896, on the Potomac River near Washington D.C., one of his craft flew. The apparatus that achieved this was remarkable. It had two pairs of wings, each slightly curved, each attached to a long steel rod which supported them both, and from which depended the body of the machine — in which were the boilers, the engines, the machinery, and the propeller wheels. The latter were nearly amidships. They were made sometimes of wood, sometimes of steel and canvas, and were three to four feet in diameter. The hull itself was formed of steel tubing. The front portion was closed by a sheathing of metal which hid from view the fire-grate and apparatus for heating, but exposed some of the coils of the boiler and all of the relatively large smokestack in which it ended. There was a conical empty float in front, to keep the craft from sinking should it fall in the water. The boiler supplied steam for an engine of between one and one-and-a-half horsepower and, with its firegrate, weighed a little more than 51b. This weight was exclusive of the weight of the engine which, with all its moving parts, weighed 260 z. It drove the propeller wheels

at rates varying from 800 to 1250 turns a minute, the highest number being reached when the machine was speeding freely ahead. The rudder was quite unlike that of a ship. It was adapted for both vertical and horizontal steering. The width of the wings from tip to tip was from 12 to 13ft, and the length of the whole body was 16ft. The weight was nearly 301 b, of which about 25 per cent was in the machinery. The engine and boilers were built for economy of weight, rather than force, and wasted steam so much that they spent their own weight in five minutes. Langley said this steam might all be recondensed and the water reused by a proper condensing apparatus. But this could not be done readily in so small a scale. With recondensation the craft might have flown for hours, but the one he built could fly for only five minutes (in theory) and in practice he limited it to two minutes so it would not fly over land and so risk being wrecked. The craft maintained itself in the air many times, but disaster always intervened to prevent a satisfactory flight. Each time he tinkered with it and refined it some more. It was on its twentieth trial flight that, launched by Langley with little hope, it finally achieved the requisite velocity and maintained its balance. The breakthrough had come, and Langley wrote afterwards: “For the first time, the craft swept continuously through the air like a living thing, and as second after second passed on the face of the stopwatch, until a minute had gone by, and it still flew on, and as I heard the cheering of the few spectators, I felt that something had been accomplished at last, for never in any part of the world, or in any period, had any machine of man’s con-

struction sustained itself in the air before for even half of this brief time. "Still it went on in a rising course until, at the end of a minute and a half (for which time only it was provided with fuel and water) it had accomplished a little over half a mile, and now it settled rather than fell into the river with a gentle descent. It was immediately taken out and flown again with equal success, nor was

there anything to indicate that it might not have flown indefinitely except for the limit put upon it.” Langley had solved the equation posed by the three problems — maintenance of velocity, achievement of equilibrium, and power'of manouevre. Another craft flew for nearly a mile on November 28 that year, and also descended with equal safety. It had been done without benefit of the (still primitive) internal combustion engine the Wright Brothers were to use in 1905,

but it blazed a way for them. Langley was in no doubt of the significance of what he had done: how correct he was. He ended the "Strand” article by saying:

“I have brought to a close the portion of the work which seemed to be specially mine — the demonstration of the practicability of mechanical flight; and for the next stage, which is the commercial and practical development of the idea, it is probable that the world may look to others. The world, indeed, will be supine if it does not realise that a new possibility has come to it, and that the great universal highway overhead is now soon to be. opened."