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The Wright brothers vs Whitehead

November 22, 2017

A few years ago, there was a flurry of excitement when Paul Jackson, the august Editor of ‘Jane’s All the World’s Aircraft’ pronounced that it was not the Wrights, but Gustav Whitehead, who was the first to achieve controlled powered flight.

 

 

 

 

Columnist Peter Garrison was unimpressed by Whitehead claims, but everybody loves a good underdog story and in all the excitement he seemed to a be a curmudgeonly voice.

Now though, I reckon he was right to be sceptical of the Whitehead claims. This despite the fact that, in late 2016, the major Whitehead protagonist, an Australian called John Brown, published a book that he claims provides irrefutable evidence that Whitehead was the first to achieve powered flight.

One of the key reasons I still support the Wright’s claim comes from a study of their creative process – how they got to that first powered flight at Kill Devil Hill.

Technology writer Kevin Ashton points out that the Wright brothers’ story begins in Germany’s Rhinow Hills on Sunday, 9 August 1896. He writes, “The sky stretched clean as a sheet, the moon chewed the sun in a partial solar eclipse, and a white shape soared between the peaks. It had the spoked wings of a bat and a crescent tail. A bearded man hung beneath: Otto Lilienthal, piloting a new aircraft, manoeuvring by shifting his weight, aiming to create a powered machine.”

A gust caught Lilienthal’s nascent weight shift hang glider. He swung his body but was unable to right it. “His great white bat fell 50 feet, and Lilienthal thrashed in its jaws. His back was broken, and he died the next day,” Ashton writes.

Orville and Wilbur read the news of Lilienthal’s death at their Wright Cycle Company store in Dayton, Ohio. Lilienthal’s sacrifice seemed senseless to them. They knew that no one should try to control a vehicle they cannot steer, especially not 50 feet up.

The brothers were making a good living from the new craze for bicycling. The serendipitous thing is that this gave them a unique perspective of the challenges of controlled flight. When we cycle, we make constant adjustments to stay balanced, which requires leaning into turns, then straightening up when the turn is complete.

The trick to cycling is balance. Lilienthal’s death showed the Wrights that the same was true of aircraft.

In their book ‘The Early History of the Airplane’, the brothers wrote: “The balancing of a flyer may seem, at first thought, to be a very simple matter, yet almost every experimenter had found in this one point something he could not satisfactorily master. Some experimenters placed the centre of gravity far below the wings. Like the pendulum, it tended to seek the lowest point; but also, like a the pendulum, it tended to oscillate in a manner destructive of all stability.

“A more satisfactory system was that of arranging the wings in the shape of a broad V, but in practice it had two serious defects: first, it tended to keep the machine oscillating; and second, its usefulness was restricted to calm air. Notwithstanding the known limitations of this principle, it had been embodied in almost every prominent flying machine that had been built. We reached the conclusion that a flyer founded upon it might be of interest from a scientific point of view, but could be of no value in a practical way.”

Wilbur added: “When this one feature has been worked out, the age of flying machines will have arrived, for all other difficulties are of minor importance.” 

This observation set the Wright brothers on the path to the world’s first flight. They saw an aeroplane as “a bicycle with wings.” The big trick to flying was not getting into the air, as Lilienthal had, but to balance. Lilienthal died because he succeeded at the first, but failed at the second. 

The Wrights solved the balance problem by studying birds. A bird balances by twisting its wings. Wilbur wrote: “To mention all the things the bird must constantly keep in mind in order to fly securely through the air would take a very considerable treatise. If I take a piece of paper, and after placing it parallel with the ground, quickly let it fall, it will not settle steadily down as a staid, sensible piece of paper ought to do, but it insists on contravening every recognized rule of decorum, turning over and darting hither and thither in the most erratic manner, much after the style of an untrained horse. Yet this is the style of steed that men must learn to manage before flying can become an everyday sport. The bird has learned this art of equilibrium, and learned it so thoroughly that its skill is not apparent to our sight. We only learn to appreciate it when we try to imitate it.”

The problem was how to reproduce a bird’s balance mechanically. Their first solution required metal rods and gears and so was too heavy to fly. Wilbur discovered the solution in the Wrights’ bicycle shop while playing with a long, thin cardboard box that had once contained an inner tube. When Wilbur twisted the box, one corner dipped and the other rose. It was a motion similar to a gliding bird’s wingtips, but it used so little force that it could be achieved with cables. And thus they invented wing warping, which led to ailerons.

The Wright brothers’ great inventive leap was not a great mental leap. Despite its extraordinary outcome, their story is a litany of little steps. For example, they spent two years trying to make Wilbur’s kite big enough to carry a pilot before discovering that the aerodynamic data they were using was worthless.

“Having set out with absolute faith in the existing scientific data,” they wrote, “we were driven to doubt one thing after another, until finally, after two years of experiment, we cast it all aside, and decided to rely entirely upon our own investigations.”

The Wrights had started flying as a hobby, with little interest in “the scientific side of it.” But they were ingenious and easily intrigued. By the time they realised that all the published data was wrong – “little better than guesswork” – they had also discovered what knowledge was needed to design wings that would fly.

In 1901 they built a bicycle handlebar-mounted test platform to simulate wings in flight, then a belt-driven wind tunnel which they used to create their own data. Many of the results surprised them. Their findings, they wrote, were “so anomalous that we were almost ready to doubt our own measurements.” 

But they eventually concluded that everybody else’s measurements were wrong. One of the biggest sources of error was the Smeaton coefficient, a number developed by 18th century engineer, John Smeaton, to determine the relationship between wing size and lift. Smeaton’s number was 0.005. The Wrights calculated that the correct figure was actually 0.0033. The net result was that wings needed to be much bigger than anybody had realised if an aeroplane was ever going to fly. 

The Wrights used the same data to design propellers. Propellers had been built for boats, but never for aircraft. Just as the brothers thought of an aeroplane as a bicycle that flies, they thought of a propeller as a wing that rotated. The lessons from their wind tunnel enabled them to design a near perfect propeller. Modern propellers are only marginally better. Likewise with the engine, when they couldn’t find one light and strong enough from the automotive industry, they designed and built their own.

The Wrights’ aircraft are the best evidence that they progressed in small steps, not revolutionary leaps. Their glider of 1900 looked like their kite of 1899. Their glider of 1901 looked like their glider of 1900 but with a few new elements. Their glider of 1902 was their glider of 1901, but bigger and with a rudder. Their 1903 Flyer – the aircraft that flew from Kitty Hawk’s sands – was their 1902 glider made bigger again, with propellers and an engine added. Orville and Wilbur Wright did not leap into the sky. They got there one step at a time.

This is contrast to Brown’s claims for Gustave Whitehead. Compared to the Wrights’ progressive achievements, Whitehead’s attempts seem crude and ill-informed. His supposedly successful Condor 21 looks like Lilienthal’s bat wings, but with a tub suspended underneath. His engine and propeller impress even less.

And then of course there’s the small matter of documentary proof for the many flights he is claimed to have made over 1901 and 1902. I find it hard to believe that from all those flights, there is not one photographic record, despite many photographs existing of his failed attempts.

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