NASA X-31 Demonstrator Model to be Permanently Installed in Armstrong Hall

Event Date: July 22, 2014
Through the generous gift of NASA Langley Research Center, the School of Aeronautics and Astronautics has received permanent ownership of the NASA X-31 Enhanced Fighter Maneuverability (EFM) demonstrator model. Previously on loan from NASA, the gift was facilitated by Alumnus Dan Vicroy (BSAAE'80), Senior Research Engineer, Flight Dynamics Branch, at Langley.

Through the generous gift of NASA Langley Research Center, the School of Aeronautics and Astronautics has received permanent ownership of the NASA X-31 Enhanced Fighter Maneuverability (EFM) demonstrator model. Previously on loan from NASA, the gift was facilitated by Dan Vicroy (BSAAE ‘80), Senior Research Engineer, Flight Dynamics Branch, at Langley.

The NASA X-31 program proved the value of using thrust vectoring (directing engine exhaust flow) coupled with advanced flight control systems, to provide controlled flight to very high angles of attack. The result was a significant advantage over most conventional fighters in a close-in-combat situation. "Angle-of-attack" (alpha) is an engineering term to describe the angle of an aircraft's body and wings relative to its actual flight path.

Alumnus Dr. Daniel Raymer (BSAAE'76, MSAAE'76) was Head of Air Vehicle design during the X-31 concept development phase, taking the project from a blank sheet of paper to the configuration that flew, except for minor loft changes done later to simplify construction. The X-31 was designed on the CDS aircraft conceptual CAD system, a system in which Dr. Raymer led development.

During the program's initial phase of flight test operations at the Rockwell Aerospace facility in Palmdale, California, the two X-31 aircraft were flown on 108 test missions, achieving thrust vectoring in flight and expanding the post-stall envelope to 40 degrees angle of attack. Operations were then moved to Dryden in February 1992 at the request of the Advanced Research Projects Agency (ARPA).

The X-31 program logged an X-plane record of 580 flights during the program, 559 research missions and 21 in Europe for the 1995 Paris Air Show. Fourteen pilots representing all agencies of the International Test Organization flew the aircraft.

The School of Aeronautics and Astronautics is pleased to have the NASA X-31 as part its permanent collection representing the important contributions of aeronautics and astronautics engineering in aircraft development.