Experimental Aircraft Achieves 70-Degree Attack Angle
WASHINGTON (AP) _ An experimental aircraft known as the X-31 has flown maneuvers at a 70- degree angle of attack, the Pentagon announced on Monday.
The development is important because most aircraft operate beyond their aerodynamic lift limit at such extremely sharp angles. They spin or tumble out of control, often with catastrophic results.
Other advanced U.S. fighter aircraft commonly do not exceed 20 to 45 degrees, the Pentagon said in a statement.
Achieving the capability would allow fighter aircraft in the future to turn tighter and point at targets more quickly than today’s fighters can.
Two of the planes, known as the X-31 EFM for enhanced fighter maneuverability, have been built to demonstrate techniques and equipment to help improve the next generation of aircraft.
On Sept. 18, a Navy test pilot was the first of six project pilots to demonstrate the aircraft’s ability to fly at extremely high angles of attack. He decelerated and stabilized the aircraft at 70 degrees angle of attack for approximately 40 seconds, a Pentagon statement said.
On Sept. 22, a Rockwell pilot demonstrated the aircraft’s controllability by flying 30 degree bank-to-bank maneuvers at 70 degrees angle of attack.
The plane first flew in October 1990.
Pictures of the aircraft in flight show it flying forward, nose lifted upward at the high angle.
All flights were flown from the National Aeronautics and Space Administration Ames-Dryden Flight Research Facility in Edwards, Calif.
The plane is able to achieve its new capabilities through a highly sophisticated digital flight-control system, the Pentagon said.
The program is a joint international experimental program with participants from the United States and Germany. It was partially funded under legislation that called for closer cooperation in weapons systems between the United States and its NATO allies.
The program includes the Defense Advanced Research Projects Agency, U.S. Navy, U.S. Air Force, NASA, Rockwell International North American Aircraft, the German Federal Ministry of Defense and Messerschmitt-Bolkow-Blohm of Munich, the Pentagon said.