Authors: Tom D. Crouch
The island looked idyllic in the quiet of that spring afternoon. Only a few acres in extent, it was covered with a thick growth of oak and pine; the land sloped gently away from steep bluffs marking the southern shore toward a marsh that blended almost imperceptibly into the Potomac on the north.
The island was the private preserve of the Mount Vernon Ducking Club, an exclusive organization of Washington sportsmen. Within the year it would become a favorite retreat for newly elected William McKinley. It was an elegant establishment, with a clubhouse, dining hall, and several well-maintained cottages set on the bluffs. But this sportsman’s paradise held few attractions for the two visitors. Samuel Pierpoint Langley and Alexander Graham Bell had come on more serious business.
They made their way toward the marsh, where a flat-bottomed scow was moored in a small cove. Dubbed the
Ark
, the strange craft featured a wooden structure almost as wide and long as the boat itself built on deck. Three large windows on either side of the deckhouse were sealed with heavy wooden shutters. A spidery wooden superstructure on the roof supported a single twenty-foot rail extending over the rear of the boat.
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Four workmen rose deferentially and escorted Langley and Bell into the deckhouse. Inside on a table lay two large winged models, broken down into subassemblies. The models—numbered, respectively, 5 and 6—represented the culmination of ten years’ effort to develop a practical flying machine.
They were works of the machinist’s art, glistening with copper pipes, brass fittings, and thin-walled steel-tube fuselages. When completely assembled they would look virtually identical to the unpracticed eye. Both machines sported two sets of tandem wings, spanning fourteen feet; from the tip of the thin forward bowsprit to the end of the cruciform tail, each measured over ten feet in length. Both were powered by delicate, lightweight steam engines driving twin propellers. The overall effect was of a pair of wispy dragonflies.
Bell had little to offer in discussion, but Langley fired one question after another at the men, determined to ensure that all preparations
for the coming test flights were complete. Then, satisfied, he led the entire party back to the clubhouse for a fine meal and a good night’s sleep.
At sixty-two, Samuel Pierpont Langley, secretary of the Smithsonian Institution for the past decade, had earned a reputation as the unofficial chief scientist of the United States. His interest in the problems of flight dated from 1886, when he attended a lecture on aeronautics at a meeting of the American Association for the Advancement of Science.
He was inspired to undertake a series of experiments to determine whether it was possible to construct a machine that would fly. Through precise measurements made with specially contrived instruments, he probed the laws of aerodynamics, being careful to emphasize that his interest was purely scientific. The program would not result in the construction of an airplane, but would “find the principles on which one should be built.”
Langley presented the results of his research in
Experiments in Aerodynamics
, published by the Smithsonian in 1891. His most significant observation was a simple affirmative statement: “The most important general inference from these experiments … is that…
mechanical flight is possible with engines we now possess.”
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The scientific community was skeptical. Some colleagues questioned the care with which the secretary had conducted his experiments; others argued that his conclusions were not supported by his experimental results. Langley, fearing for his reputation, set out to provide a practical demonstration of the validity of his work.
Between 1887 and 1891, he and his staff constructed more than one hundred flying models sporting various wing, tail, and propeller combinations, each powered by strands of twisted rubber. None met his expectations. He then turned to the design of even larger craft, with wingspans in excess of ten feet, to be propelled by small steam engines. With Smithsonian funds, he mounted a five-year effort to launch these machines into free flight. One model followed another—the first was too heavy, the second too light, the third too weak. The little engines were refined and perfected during this period. Experiments were conducted with catapult launching systems. For all of this preparation, there had not been a single successful flight. Trial after trial had ended with the craft falling into the water off the end of the launch rail. By the spring of 1896 Langley’s critics were feeling rather smug.
The Wrights were inspired by a flurry of aeronautical activity in 1896. Samuel Pierpont Langley had flown two of his Aerodromes, including Number 6, over the Potomac that year.
Aerodrome No. 6 was ready to go by 1:10 on the afternoon of May 6. Luther Reed, superintendent of the Smithsonian carpentry shops, stood behind the machine, ready to pull the lever that would release a powerful streetcar spring and send the craft rushing down the rail once again. One of the guy wires holding the frail wings in place snapped at the moment of launch, allowing the left forward wing to bend sharply up. The sight of their precious Aerodrome arcing violently into the river was a familiar one to the launch crew, but no less disappointing. Fishing the remains out of the water, they found the wing and both propellers smashed and the engine severely damaged. There would be no more tests with No. 6 that day.
The second model, No. 5, was hoisted into position and prepared for a trial by three o’clock. Each member of the party was at his appointed place. As before, Reed would operate the catapult from a scaffold. Bell stood on the narrow deck beside a nervous Smithsonian photographer. Number 6 had entered the water too quickly for the fellow to snap a picture. Langley was angry, and let him know that it was not to happen a second time.
With one hundred fifty pounds of steam in the boiler and the propellers spinning at top speed, Reed pulled the release. No. 5 left the rail twenty feet above the water, dropped three or four feet, then moved into the wind, angling up some 10 degrees from the horizontal. The men who had grown so accustomed to failure were struck dumb.
The machine began a slow climbing turn, circling the houseboat twice as it gained altitude. It was 100 feet in the air when the steam
was exhausted 90 seconds after launch. The propellers ground to a halt and the little machine settled gently onto the river. It had traveled 3,000 feet through the air, over half a mile, at a speed of 20–25 miles per hour.
Stunned silence gave way to a ragged cheer. The crew retrieved the craft, dried and reguyed it with great care. They launched it again at five o’clock that afternoon. The second flight was another triumph. Langley was ecstatic. His belief in the possibility of heavier-than-air flight had long threatened to blot one of the most distinguished careers in American science. Even his colleagues at the Smithsonian were concerned lest the secretary’s aeronautical obsession damage the reputation of the Institution.
The flights of May 6, 1896, were his vindication. As he noted in his diary that evening: “These experiments were beyond comparison the most satisfactory which have yet been made, and they have probably no parallel in the history of the subject.”
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Early Sunday morning, August 2, 1896, Robert Wood, a correspondent for the Boston
Transcript
, met Otto Lilienthal on the platform of Berlin’s Lehrter Station. Lilienthal, dressed in a flannel work shirt, twill knickerbocker trousers with thickly padded knees, heavy brogans, and a close-fitting knit skullcap, arrived just before dawn, accompanied by his fourteen-year old son and a mechanic from his machine shop. He looked the image of an athlete—compactly built, broad-shouldered, barrel-chested, with a head of curly red hair, a full beard and mustache, and a ready smile that had etched deep lines around his eyes.
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Together, the four men boarded a train headed for the Rhinow Mountains, a range of lush hills forty miles to the north. This excursion was a weekly ritual for Lilienthal, who retreated to the seclusion of Rhinow each Sunday to continue a series of manned glider flights that had brought him world fame since 1891. Fascinated by bird flight since boyhood, Lilienthal had begun his serious study of aeronautics in 1879.
He published the results of his laboratory research in a book,
Der Vogelflug als Grundlage der Fliegekunst (Birdflight as the Basis for Aviation)
, which appeared in 1889.
Vogelflug
, and his other articles,
provided a foundation of solid research for other men who sought to fly.
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The laboratory tests and publications were the necessary preliminaries to the real business of designing a flying machine. Unlike Langley and most other experimenters, Lilienthal did not believe in the value of models. He was convinced that the conquest of the air would begin with manned gliders. Only by testing a series of unpowered craft for himself could an engineer achieve the process of refinement that would lead to a successful powered machine capable of sustained flight with a pilot on board.
Between 1891 and 1896 he completed nearly two thousand glides in sixteen separate glider types. Most of these were simple monoplanes with stabilizing surfaces at the rear, but Lilienthal also experimented with biplane designs and variations of his standard bat-like monoplane. Ribs and other covered portions of the craft were constructed of split willow and bamboo. The wings, which resembled “the outspread pinions of a soaring bird,” averaged between 10 and 20 square meters in area and were covered with cotton twill sheeting doped with a special colloidal solution that created an airtight surface.
The normal glide ratio of these machines averaged eight feet of forward flight for every foot of fall. In all Lilienthal machines, the pilot hung upright between the wings, controlling the craft by shifting his own weight to alter the center of gravity. Hence the term “hang glider.”
Nowhere had Lilienthal’s work found a more receptive audience than in the United States. This name was familiar to many readers of American newspapers and magazines; accounts of his exploits provided a rich source of material that captured the imagination of the public. Wood was the latest in a string of reporters dispatched to satisfy the American appetite for news of the “flying man.”
At the site, Lilienthal supervised the unloading and assembly of the glider, a biplane with a twenty-foot wingspan and a six-foot gap between the upper and lower wings. Wood was enthralled by the sight of the machine taking shape on the grass.
So perfectly was the machine fitted together that it was impossible to find a single loose cord or brace, and the cloth everywhere was under such tension that the whole machine rang like a drum when rapped with the knuckles…. Here was a flying machine, not constructed by a crank, to be seen at a county fair at ten cents a head, or to furnish material for
encyclopedia articles on aerial navigation, but by an engineer of ability … a machine not made to look at, but to fly with.
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While Wood positioned his camera, the other three men carried the glider up to the crest of a hill. Lilienthal crawled underneath, worked his arms into a set of cuffs that would give him leverage on the machine, grasped a bar near the forward edge of the wings, and stood “like an athlete waiting for the starting pistol.” As the wind freshened, he took three steps downhill and was immediately lifted into the air. Flying straight out from the summit, he passed over Wood’s head at an altitude of fifty feet, “the wind playing wild tunes on the tense cordage of the machine.”
A sudden gust caught the left wingtip, lifting it and sending the craft into a broad, sweeping turn from which Lilienthal recovered with a powerful throw of his legs. He swooped low over the fields at the base of the hill, “kicking at the tops of the haystacks as he passed over them.” Approaching the ground, he kicked forward to raise the leading edge of the wing, brought his craft to a dead stop in the air, and dropped easily to earth.
The young reporter found it difficult to contain himself. “I have seen high dives and parachute jumps from balloons,” he exulted, “… but I have never witnessed anything that strung the nerves to such a pitch of excitement, or awakened such a feeling of enthusiasm and admiration as the wild and fearless rush of Otto Lilienthal through the air.”
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Toward the end of the afternoon, having witnessed ten flights, Wood wanted to try his hand at gliding. Lilienthal agreed and ordered the machine taken only a dozen yards up the slope. Wood quickly discovered that simply standing in one place balancing the glider was so difficult as to give him a feeling of “utter helplessness.” “As you stand in the frame, your elbows at your side, the forearms are horizontal, and your hands grasp one of the horizontal cross-braces. The weight of the machine rests in the angle of the elbow joints. In the air, when you are supported by the wings, your weight is carried on the vertical upper arms and by pads which come under the shoulders, with the legs and lower part of the body swinging free below.”
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