He praised the work of both Lilienthal and Chanute. “Lilienthal not only thought, but acted. . . . He demonstrated the feasibility of actual practice in the air, without which success is impossible.” Noting that Lilienthal, over a period of five years, had spent no more than five hours in actual gliding, he said the wonder was not that he had done so little, but that he had accomplished so much. What if a bicycle rider tried to ride through a crowded city after only five hours’ practice, spread out in bits of ten seconds over a period of five years?
He praised the biplane developed by Chanute as a “very great structural advance” and told how, with a few changes, he and Orville had built and tested their own double-deck glider in Outer Banks winds of up to 27 miles per hour.
Much that followed in the published version of the speech was highly technical and included mathematical equations and diagrams of wing curvatures. (“Do not be afraid of making it too technical,” Chanute had urged.) How critical Wilbur had been about the unreliable data compiled by Lilienthal and Chanute when addressing the Chicago gathering is unknown, since no stenographic record was made of the actual speech. But in the published version he pulled back considerably out of respect for Chanute. Of Lilienthal’s tables, he went only so far to say Lilienthal might have been “somewhat in error.”
If Chanute took issue with anything Wilbur said, or was in any way offended, he never let on. In a letter written after he finished proofreading the speech before publication, Chanute called it “a devilish good paper which will be extensively quoted.”
That Wilbur returned to Dayton from Chicago even more grateful for Chanute’s friendship and counsel can be seen in the increased volume of their correspondence. Over the next three months, until the end of the year, Wilbur would write to Chanute more than twelve times, or once a week on average. Some of the letters ran as long as seven to nine pages, and Chanute invariably replied without delay.
Meanwhile, an article in the September issue of the popular McClure’s Magazine written by Simon Newcomb, a distinguished astronomer and professor at Johns Hopkins University, dismissed the dream of flight as no more than a myth. And were such a machine devised, he asked, what useful purpose could it possibly serve? “The first successful flyer will be the handiwork of a watchmaker, and will carry nothing heavier than an insect.”
With their former trust in the calculations of Lilienthal and Chanute shattered, the brothers set out that autumn of 1901 to crack the code of aeronautics themselves. It was a brave decision and a crucial turning point.
Of primary importance was to find a way to achieve accurate measurements of the “lift” and “drag” of a wing’s surface, and the ingenuity, as well as patience, they brought to their experiments were like nothing done by anyone until then. For three months, working in one of the upstairs rooms at the bicycle shop, they concentrated nearly all of their time on these “investigations” and with stunning results.
They devised and built a small-scale wind tunnel—a wooden box 6 feet long and 16 inches square, with one end open and a fan mounted at the other end, and this powered, since the shop had no electricity, by an extremely noisy gasoline engine. The box stood on four legs about waist high.
Although a wind tunnel had been used by an English experimenter, Francis Herbert Wenham, as early as the 1870s, and by several others since, including Hiram Maxim, their tests were nothing like those of the brothers, who proceeded entirely on their own and in their own way.
For testing apparatus inside the box, they used old hacksaw blades cut to different sizes with tin shears and hammered into a variety of shapes and thicknesses—some flat, some concave and convex, or square or oblong, and each about six inches square and one-thirty-second of an inch thick—these strung on bicycle spoke wires.
Though such apparatus did not look like much, it was to prove of immense value. For nearly two months the brothers tested some thirty-eight wing surfaces, setting the “balances” or “airfoils”—the different-shaped hacksaw blades—at angles from 0 to 45 degrees in winds up to 27 miles per hour. It was a slow, tedious process, but as Orville wrote, “those metal models told us how to build.”
Octave Chanute was astonished by what Wilbur had to report. “It is perfectly marvelous to me how quickly you get results with your testing machine,” he wrote. “You are evidently better equipped to test the endless variety of curved surfaces than anybody has ever been.” When Wilbur apologized for writing to him at such length, Chanute assured him his letters were always too brief.
The work was unlike anything the brothers had ever undertaken and the most demanding of their time and powers of concentration. They were often at it past midnight. As said later in the Aeronautical Journal of the Aeronautical Society of Great Britain, “Never in the history of the world had men studied the problem with such scientific skill nor with such undaunted courage.”