American aerospace engineer Burt Rutan was a pioneer of experimental homebuilt light aircraft kits using composite materials. The Defiant was intended to be an efficient, safe twin engine aircraft that did not have the engines mounted on the wings. This meant that the pilot would not have to deal with yaw, or spin, in the event of a potentially fatal engine failure and could retain moderate directional control. This was achieved by mounting both engines on the aircraft center axis in a “push-pull” configuration – one engine in front of the cockpit and another in the rear. A forward-canard design provided pitch control and fixed landing gear augmented the Defiant’s simplicity and lightweight construction. Its unusual rudder is mounted under the plane’s cabin, beneath the pilot, and it has no flaps. Each Titan O-320 piston 167-horsepower engine has its own ignition key.

The Defiant was never certified as a production aircraft; the prototype Model 40 (N78RA) made its maiden flight from Mojave, California in June 1978. The Defiant was then offered as the Model 74 as a kitplane in 1984. Over a dozen were completed and registered with the FAA. It may have never achieved widespread success due to the intensive process of certifying such an experimental design, but it was a valuable contribution to Rutan’s catalog of revolutionary concept planes.

This original Defiant prototype, model 40, was retained by Burt Rutan as his personal aircraft prior to its donation to the Hiller Aviation Museum.