Authors: Tom D. Crouch
Chanute offered Wilbur yet another proposal in March. During a recent trip to California he had met Charles H. Lamson, a veteran flying-machine experimenter. In 1895, Lamson had built and flown the first Lilienthal glider in America. The next year he made national headlines with a gigantic man-lifting kite. Convinced that there was little money in aeronautics, Lamson then moved to Pasadena and opened a jewelry store.
Attempting to rekindle his interest, Chanute offered Lamson a contract for the construction of a new folding-wing glider. Lamson accepted. With one glider under construction, Chanute asked if the Wrights would accept a similar contract to build new versions of the two-surface machine and the Katydid of 1896.
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Wilbur agreed that he and his brother would oversee the production of the glider, but he let Chanute know that it was an imposition. They could not begin until after the close of the busy summer season at the bicycle shop, and would insist that he provide them with a complete set of drawings. The Wrights wanted to be sure that there was no confusion—this was to be Chanute’s machine, not their own. They were not willing even to construct the craft themselves, but would hire a carpenter to work under their supervision.
Chanute accepted their terms, then changed his mind. In mid-May, he received an unexpected letter from Augustus Herring, the young engineer who had played an important role in the design and testing of the 1896 gliders. Herring was out of work and asking for help.
Chanute and Herring had parted company on less than pleasant terms before the end of the Dune trials in 1896. Herring had been eager to rush ahead to the construction of a powered version of the biplane glider; Chanute held back, insisting on additional tests. He told his friend James Howard Means that Herring “tries very sulkily those experiments that do not originate with him, and is … very obstinate.”
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Still, Chanute felt sorry for the fellow. Things had not gone well for Herring. After leaving Chanute, he found a new patron in Matthias Arnot, an Elmira, New York, banker who funded the construction of another biplane glider in 1897. With Arnot’s continued support, Herring constructed a powered machine the following year, a variant of the Chanute-Herring biplane glider fitted with a small compressed-air engine. Herring completed two very short hops with the little craft during the fall and winter of 1898. On the first occasion he skimmed forward over the sand of a Lake Michigan beach some fifty feet. A few weeks later he made a longer hop of seventy-three feet.
Herring’s two short forays into the air proved nothing. His machine was no more than a standard hang glider with a lightweight engine capable of running for only a few seconds. Having made his brief powered hops, Herring found himself at a technological dead end. The primitive and ineffective body-shifting control system placed such limitations on the surface area that the wings could barely support the weight of the pilot and the tiny engine. Woefully underpowered, the little biplane was not remotely capable of sustained flight. If anything, Herring’s 1898 powered hang glider was proof positive of the need for a revolutionary breakthrough such as the Wrights had achieved in the areas of aerodynamics and control.
Herring’s dreams of moving on to a larger machine were dashed by a fire that destroyed his workshop, aircraft, and experimental engines in 1899. Arnot’s death of peritonitis in 1901 cut off any hope of additional financial support. Desperate to remain involved in aeronautics, Herring swallowed his pride and came back to Chanute.
Herring knew of Chanute’s interest in the two newcomers from Dayton. He had read Wilbur’s paper, and been much impressed. But he realized too that Chanute believed in the value of friendly competition. So he wrote to Chicago suggesting that, given the funds for a new glider, he could “beat Mr. Wright.”
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Intrigued, Chanute asked the Wrights to release him from their agreement so that he could offer the contract to Herring. Wilbur assured him that they would be happy to see the work go to Herring. “To tell the truth,” he added, “the building of machines for other men to risk their necks on is not a task that we particularly relish.”
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Chanute wrote back at once, explaining that Wilbur had misunderstood. He intended to offer Herring nothing more than a construction contract. Both the Herring and Lamson machines were meant as a gift to the Wrights—they could fly them to their hearts’ content at Kitty Hawk during the coming season. Wilbur’s rejection of the offer was polite but very firm. The Wrights were eager to build a new glider embodying both the lessons learned in their two previous seasons and the new wind-tunnel data. The last thing they wanted was to waste time testing one of Chanute’s old designs.
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Chanute pressed the issue when he visited Dayton on July 3. If the brothers refused to test his gliders, would they allow Bill Avery or Herring, both of whom had flown the craft in 1896, to join them at Kitty Hawk? Again the Wrights were hesitant, responding by letter soon after Chanute’s departure.
“It was our experience last year,” Wilbur explained, “that my brother and myself, while alone, or nearly so, could do more work in one week, than in two weeks after Mr. Huffaker’s arrival.” If Chanute would give them enough time on their own to establish camp and conduct some preliminary tests with their glider, however, they would welcome him and his “expert” as their guests. “Provided it is equally satisfactory to you,” Wilbur concluded, “reasons not necessary to mention would lead to a preference for Mr. Avery in the choice of an expert.”
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All their attention now focused on the new glider. The calculations called for a machine slightly larger than the 1901 craft, with a wing surface area of 305 square feet. The whole point of the wind-tunnel tests had been to choose the most efficient wing surface. Number 12 on their tables of lift and drift, it was a small steel blade with an aspect ratio of 1:6 (as opposed to 1:3 of 1900 and 1901), a camber of
1
/
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, and the peak set one quarter of the way back the chord from the leading edge.
Full scale, the new wing gave the finished machine a radically different appearance from its two predecessors. The span was over ten feet longer than in 1901 and the chord two feet shorter. To a modern eye, the 1900 and 1901 gliders seem bulky and cumbersome, with their stubby rectangular wings. The 1902 craft, lighter and more graceful, looks like an airplane.
The addition of a two-surface fixed vertical rudder at the rear of the machine also changed its look. Just as the new wing was designed to overcome the aerodynamic problems of its predecessors, the rudder was intended to deal with the control problems Wilbur had encountered at the close of the 1901 season.
The brothers reasoned that the problem stemmed from differential drag induced when the wing was warped. Take a typical example from 1901: On August 9, Wilbur was skimming along in straight and level flight when the left wingtip dropped. He shifted the hip cradle to the right to bring it back up. As the wing rose, the entire machine skidded sideways to the left. Sensing danger, the pilot dropped the craft abruptly onto the sand.
When the wing was warped, the angle of incidence of the left tip increased, to increase the lift, while that of the right tip decreased. Such action did raise the left tip, but it also increased the drag on that wing, causing it to move more slowly than the right wing and pulling the entire aircraft into the strange skid. The addition of the fixed rudder was designed to counteract that motion. When the machine began to nose toward the slow wing, the rudder would also present an angled surface to the wind, increasing the total drag on the opposite side and correcting the differential.
There was frantic activity in the Wright household during July and August. Wilbur dashed off a letter to Spratt, inviting him back to Kitty Hawk. If they had to put up with an “expert” who promised to rival Huffaker as a companion, they might as well have a friend along too. Another letter went to Bill Tate, asking for permission to reoccupy the old Kill Devil Hills site rent-free. Will, worried about the White River Conference proceedings, was torn between making a trip to Huntington on his father’s behalf and remaining in Dayton to assist Orv with work on the new machine.
Katharine thought her brother looked “thin and nervous,” and urged him to get on with preparations for the trip to Kitty Hawk. “They will be all right once they get down in the sand where the salt breezes blow,” she wrote Milton on August 20. “They insist that, if you aren’t well enough to stay out on your trip, you must come down with them. They think that life at Kitty Hawk cures all ills, you know.” In truth, Katharine looked forward to their departure with mixed emotions. “Will spins the [sewing] machine around by the hour while Orv squats around marking the places to sew. There is no place in the house to live, but I’ll be lonesome enough by this time next week and wish that I could have some of the racket around.”
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They left Dayton at 9:00
A.M.
on August 25, bound once again for Elizabeth City by way of Norfolk. Chanute wrote that both Lamson and Herring were ready to ship their respective machines at any time. Avery was not available. Would the Wrights accept Herring instead?
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Wilbur was blunt. They had been told that Herring was a man of “somewhat jealous disposition,” and were afraid that he might use what he saw at Kitty Hawk, or claim that the Wrights had made use of something they had learned from him. Wilbur shifted the burden back to Chanute, adding: “[I]f you are also in camp during the term that he is here I do not see how any misunderstanding could arise.”
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The first few days at Kill Devil Hills were spent putting the 1901 shed back into shape. The wind had scoured the sand from beneath both ends of the building, giving the roof, as Will said, “a shape like that of a dromedary’s back.” They raised the ends back into place and added corner pilings, then extended the rear to create a kitchen and living room. The sleeping quarters would be up in the “attic” this year. The brothers installed two beds running lengthwise over the rafters.
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They spent the morning of Monday, September 8, cleaning out the shed; killing two mice (“one with a stick, the other with gun”); and chasing several hungry razorback hogs away from the campsite. Work on the new glider began just after two o’clock that afternoon. The rest of the week passed quickly. Each wing was tested as an individual unit. The Wrights were pleased with the results: lift and drag were close to the predicted values, and the reversal of the center of pressure occurred at a much lower angle than they had hoped for.
By September 15 the struts salvaged from the old 1901 machine were in place and the complete wing set was taken out for a trial. It was, Will told Spratt, “an immense improvement over last year’s machine.” Four days later they made the first kite and gliding tests with the finished craft, complete with the elevator and new fixed rudder. When Wilbur wrote to Chanute on September 21, they already had fifty glides under their belts.
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Will was doing so well with the new machine that he could bring it to a virtual standstill in the air. And Orville was finally learning to fly. He began with short glides, accustoming himself to the use of the elevator. Teaching oneself to fly is never easy, particularly with an older brother shouting up instructions from below. The situation led to a near disaster on September 23.
It was perfect flying weather after two days of torrential rain. The Wrights were out all day, completing seventy-five glides of varying length. On the final glide Orv shifted the hip cradle to raise a dropping wing, and lost track of the elevator. The craft nosed up into a steep stall and fell backward onto the sand. The result, was “a heap of flying machine, cloth, and sticks in a heap, with me in the center without a scratch or bruise.”
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They were back in the air a week later, rapidly gaining experience with the rebuilt machine. By October 2 they were averaging twenty-five flights on good weather days and achieving distances of over 500 feet on occasion. Those glides were the first fruits of the long winter days spent peering into the glass on top of the wind tunnel. The 1902 glider exceeded its calculated performance. The brothers could not have been more pleased.
The 1902 glider was the result of lessons learned with two previous machines and the wind-tunnel experiments. This is Wilbur in the air on October 2, 1902. The original double-surfaced rudder was fixed and could not turn.
At the same time, it was clear that the fixed rudder did not solve the dilemma of aerial skids caused by differential drag during wing warping. The problem was growing worse, and may even have been involved in Orville’s spectacular crash on September 23.
Lying awake up in the rafters after his brother had fallen asleep on the night of October 3, it occurred to Orv that the fixed rudder might be at fault. In a crosswind, the additional drag of the tail could further retard the slow wing. Why not hinge the rudder, adding a new control, so that the pilot could actively turn the surface to counteract the increased drag on the low wing?