The Rutan Model 40 Defiant
is a four-seat, twin-engine aircraft with the engines in a push-pull configuration
. It was designed by well-known aerospace engineer Burt Rutan
for the Rutan Aircraft Factory
The prototype Defiant, N78RA, first flew on 30 June
. It was intended as a proof-of-concept of a very safe light twin design, requiring little trim change and no pilot action in case of engine failure, and with good single engine performance. A comparison of the Defiant single engine climb rate with a Grumman Cougar showed about 390 vs 280 ft/min at low altitude with both aircraft cleaned up. The prototype is now owned by the Hiller Aviation Museum
In 1979 the Rutan Aircraft Factory announced they would proceed with certification of a Defiant-based light twin. Adequate financing was not secured for this project, and the design was modified for homebuilt construction as the Model 74, with the second aircraft (built by Fred Keller) appearing at Oshkosh 1983. Plans were offered in mid-1984. Nine examples were known to be flying as of mid-1987. Nineteen are registered with the FAA as of 2005.