The M2-F3 Lifting Body is seen here on the lakebed next to the NASA Flight Research Center (FRC--later Dryden Flight Research Center), Edwards, California. The May 1967 crash of the M2-F2 had torn off the left fin and landing gear. It had also damaged the external skin and internal structure. Flight Research Center engineers worked with Ames Research Center and the Air Force in redesigning the vehicle with a center fin to provide greater stability. Then Northrop Corporation cooperated with the FRC in rebuilding the vehicle. The entire process took three years.