He is noted primarily as one of the early developers of terrain following technology[1] and a proponent of incorporating energy management theory into the design of fighter aircraft.
He won the Wright Brothers Medal in 1974 with Ralph Pruitt, Gordon G. Grose, and J. L. Porter for a paper discussing future aircraft designs that integrate fly-by-wire controls with engine inlets/nozzles and advanced pilot displays.
[3] Wendl joined McDonnell Aircraft working in guidance and flight control systems, which at this time were topics experiencing rapid advancements.
In 1968, he co-authored a paper documenting the development of vertical terrain-following capability based on the General Electric 666A actuator system as applied to fighter-bomber aircraft, in particular the F-4.
Wendl directed the fuel system design and development program and later contributed to various engineering refinements to subsequent models of the Eagle.