Wright Flyer III

The Wright Flyer III was the third powered aircraft by the Wright Brothers, built during the winter of 1904-05. Orville Wright made the first flight with it on June 23, 1905. The Flyer III had an airframe of spruce construction with a wing camber of 1-in-20 as used in 1903, rather than the less effective 1-in-25 used in 1904. The new machine was equipped with the engine and other hardware from the scrapped Flyer II and—after major modifications—achieved much greater performance than Flyers I and II.
As initially built, the Flyer III looked almost the same as its predecessors and offered equally marginal performance. Orville suffered minor injuries in a serious nose-dive crash in the machine on July 14, 1905. When rebuilding the airplane, the Wrights made important design changes that solved the stability problems of the earlier models. They almost doubled the size of the elevator and rudder and moved them about twice the distance from the wings. They added two fixed half-moon shaped vertical vanes between the elevators and widened the skid-undercarriage which helped give the wings a very slight dihedral. They disconnected the rudder of the rebuilt Flyer III from the wing-warping control, and as in most future aircraft, placed it on a separate control handle. They also installed a larger fuel tank and mounted two radiators on front and back struts for extra coolant to the engine for the anticipated lengthy duration flights. When testing of Flyer III resumed in September, improvement was obvious. The pitch instability that had hampered Flyers I and II was brought under control. Crashes, some of which had been severe, no longer occurred. Flights with the redesigned aircraft started lasting over 20 minutes. The Flyer III became practical and dependable, flying reliably for significant durations and bringing its pilot back to the starting point safely and landing without damage.

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