Boeing’s Proposed New Airplane Resembles Wright Flyer

by Dr. Richard Stimson

in Others

A prominent feature of the Wright Flyer that successfully flew at Kitty Hawk, NC is the forward protruding horizontal elevator or canard configuration. Most people are puzzled by the configuration because most modern airplanes incorporate the horizontal elevator into the tail of the airplane.

Sonic Cruiser

This may soon change. Boeing recently announced their concept for a new generation of commercial airplanes. They call it the “Sonic Cruiser.” Their design employs canards in a fashion similar to that employed by the Wright Brothers in their early airplanes.

A canard configuration refers to any horizontal surface that is placed ahead of the wings.

The Boeing design team is focusing on an airliner that could operate above 40,000 feet at Mach .95 (95% of the speed of sound.) or greater over a range of 10,350 miles carrying 500 to 600 passengers. The Sonic Cruiser would save an hour and a half on a North Atlantic route and two and a half-hours across the Pacific.

The Sonic Cruiser also employs a double tail just like the Wright Flyer.

Lilienthal Killed

The Wright Brothers had very specific reasons for utilizing the canard configuration. First was safety. The Wrights were very familiar, even afraid of the kind of sudden, uncontrollable dive that killed Lilienthal, the famous German glider experimenter, in 1896.

Lilienthal had experienced a phenomenon known as a “stall.” A stall occurs under the conditions of climbing when the angle at which the wing strikes the air is so great that the airstream passing over the top side of the wing breaks away and turbulence sets in. The wing immediately losses all lift. If a stall occurs too close to the ground for the pilot to recover, a fatal crash inevitably occurs.

The Wrights, as with all the other experimenters, were only vaguely aware of how wings reacted to the air pressure created by the wind flowing over them. The Wrights thought that the tendency of pressure on a wing in level flight was to turn the nose of the glider upward. Their forward elevator was designed to exert a counteracting nose-down pressure. Later they would find that the tendency was just the reverse, to nose dive, but their elevator would still work to counteract this pressure and provide fore and aft control.

Canard Prevents Fatal Crashes

They were lucky in that the canard design provided an unexpected additional benefit. Wilbur found this out to his good fortune while flying their glider in 1901. He was flying at about 30-feet when suddenly he lost forward speed and the nose of the glider moved upward. Adjusting the elevator was having no effect. Desperately, Wilbur moved his body forward as far as he could to bring the nose down. To the surprise of Wilbur and worried onlookers, instead of a neck-breaking dive, the glider gently “parachuted” to the ground.

Later in the day, he stalled again. This time the strong wind was blowing the glider backward in what looked like would be a deadly tail-slide and tumble to the ground. Again Wilbur was able to bring the glider to earth with a mush-like glide. The Wrights decided to keep the design with the elevator up-front, certain it provided protection from nose-dives.

An additional advantage of the canard design was that the elevator in front provided a visual indicator of the glider/airplane’s attitude in flight. This is crucial as an aid for a pilot to maintain control of his aircraft and particularly important for the Wrights who were teaching themselves how to fly.

There is a downside to the canard design. It is very sensitive to movement. This often resulted in the Wrights experiencing undulating flight paths. The sensitivity increased with speed. When the Wrights began to build airplanes with speeds above 60 mph in 1910, they moved the elevator to the rear.

Foundation of Aeronautical Engineering

The Wright Brothers had started out to make some small contribution to aeronautical progress. But in three years of study and experimentation, the brothers had surpassed all other flight researchers. They established theories and practices of Aeronautical Engineering still used in all aircraft design today, including the space shuttle.

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