The Wright Brothers 1903 Flyer replica is providing revolutionary insight about the original plans of the Wright brothers. This data along with future research could impact a wide range of supersonic and hypersonic aircraft designs.  

When NASA began the wind tunnel testing of the 1903 Flyer replica in 1999, they expected only to learn about the low speed characteristics of the craft.  Subsequent to the wind tunnel tests and the discovery of new documents, NASA is rethinking the entire goal of the original Flyer project as conceived by the brothers in the early 1900s.  "It appears that the brothers intended to leapfrog subsonic flight and go directly into supersonic regimes" said Stuart Clides, a NASA engineer at Dryden.  "We were shown papers describing their designs along with descriptions of shock wave interactions and other supersonic considerations.  Of course it was inconceivable that supersonic flight could precede subsonic flight, but this shows how truly advanced their work was."  

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"It appears that the brothers intended to leapfrog subsonic flight and go directly into supersonic regimes" 

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This new insight explains a lot of the design evolution of the Wright Brothers aircraft.  "It would appear that the only hindrance to their plans for supersonic flight was a suitable power plant." Clides says, "We all know how the Wrights built their engine themselves out of the frustration of not being able to purchase one that was light or powerful enough.  What we didn't realize, and perhaps what the vendors they approached at the time didn't realize, was the application they envisioned."  An interesting design element missing in their original engine was a carburetor.  The fuel was vaporized by dropping onto a hot plate.  At very low speeds this is inferior to a carburetor which has jets to atomize the fuel.  However the Wrights envisioned the engine operating in a high mach number environment.  In this regime the unique design of the Flyer allowed for this fuel vaporization mechanism to work perfectly.

The fuel issue was uncovered when NASA began supersonic wind tunnel testing of a small Flyer model.  The most intriguing element of the test was the interaction of the shock waves between all of the surfaces of the Flyer.  Conventional supersonic design theory attempts to minimize these interactions with simple sleek designs.  Conversely, the Flyer is made up of masses of wires and wing elements.  Multiple shock waves develop and interact in an "interference pattern" that apparently cancels out and reduces total drag.  This is a tremendously complicated system that the brothers seemed to understand intuitively.  Complex computer simulations have not been able to replicate this phenomena.

In order to better understand the flight mechanics involved, NASA is beginning a series of powered and un-powered flight tests of the Flyer.  Later flights will use the Pegasus solid rocket booster to push the Flyer to speeds of over Mach 3.  

Other design features the Wrights invented are explained by the new supersonic theory.  For example, the Wrights invented (and patented) wing warping whereby cables pull on the corners of the wings causing them to twist.  Additionally the rudder and canard control surfaces consist of the entire movement of the structure (all-flying).  These surfaces work perfectly at high mach numbers.  Nevertheless, wing warping was quickly replaced by tabs on the wings known as ailerons. Elevators and rudders were transformed into fixed surfaces with movable tabs in the rear.  These surfaces were perfectly adequate for the low speed aircraft through WWII but inadequate in supersonic regimes because they are blanked out by the shock waves.  Nearly fifty years later, when Chuck Yeager and the X-1 "re-pioneered" supersonic flight, the "all flying" tail was reinvented. 

Other evolutionary steps NASA scientists wish to explore include the canard surface itself.  The Wrights abandoned the canard surface in 1910 for what we now call a 'conventional' tail in the rear of the aircraft.  Does the canard have special features at the high mach numbers envisioned by the brothers?   Perhaps this change was the resignation by the brothers to flight in the subsonic range for the foreseeable future.