Who Were Wilbur and Orville?
1899 1900 1901 1902 1903 1904 1905
1903
The Bicycle Apparatus
The bicycle apparatus
In the fall of 1901, the Wrights began to test the accuracy of the equations they had been using. Tapping their familiarity with bicycles, they created a device to compare the forces acting on two objects with different shapes.
The Wright Bicycle Apparatus
The Bicycle Apparatus
How it worked
The Wrights examined all the terms in the lift and drag equations. Some values—weight of the craft, wind speed, and wing surface area—could be directly measured, so the Wrights were confident of their accuracy. But the coefficients of lift and drag and Smeaton’s coefficient were drawn from the work of others. The brothers focused on these as the possible source of their gliders’ poor lift performance.
Calculations and results
They recorded the angle of the wing to the airflow at which the air pressure on the wing shape balanced the air pressure on the plate. This is called the angle of attack.
Then they calculated what Lilienthal’s data indicated the angle should have been. The model wing required more than three times the angle of attack than Lilienthal’s data predicted.
 
The Wrights concluded that either Lilienthal’s data or Smeaton’s coefficient—or both—were in error.
Go to The Wright Wind Tunnel >>
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