This look-down view of NASA's two X-29 research aircraft shows the aircraft lit by the golden rays of early morning on Rogers Dry Lake, adjacent to NASA's Ames-Dryden Flight Research Facility (later Dryden Flight Research Center), Edwards, California. Aircraft No. 1 flew from 1984 to 1988 and investigated general handling qualities, performance, and systems integration. The second aircraft flew from 1989 until 1992 in a program to investigate high angle-of-attack characteristics. Angle of attack (AOA) refers the angle of an aircraft's body and wings relative to its actual flight path.