by Henry Jex
March 19, 1999
Preliminary plots of key data reveal some interesting differences from earlier unpowered model tests of a small-scale steel model. The billowing of the actual fabric between ribs creates more wing camber (chordwise curvature) as the lifting pressure increases at increasing angle-of-attack, giving a higher lift-curve-slope.
Even though the propellers don't blow on any model surface, they produce some consistent differences compared with props-off. The wing warping scheme worked very well, and the fear of aerodynamic flutter of such a torsionally limber wing structure was not realized. The extremely unstable properties of the 1903 Flyer were verified, and this proved that the Wrights long practice in their gliders was an essential ingredient in their success.
Additional data were obtained that will help us design a safer, "stand-off scale" version of the Wright Flyer, which we hope to fly in 2003; 100 years later.
So this unique wind tunnel test of an exact, full scale replica of the 1903 Wright flyer fully proved the aerodynamic and structural ingenuity of the Wright Brothers and the durability of their seemingly flimsy chain-driven propellers. Their tough design flew for more hours in the NASA Full Scale Wind Tunnel than in all of their flights of 1903 and 1904 put together!