DC-XA was the upgraded configuration of the DC-X demonstrator tested by NASA and the Department of Defense in 1996. A graphite-epoxy hydrogen tank, aluminium-lithium oxygen tank, lightweight intertank and improved reaction control reduced dry mass by about 620 kg. Four flights included two launches separated by 26 hours. On 31 July 1996 one landing strut failed to extend; the vehicle tipped over and was destroyed in the resulting fire. Its low-altitude tests demonstrated reusable operations, not single-stage access to orbit.
Future launches and major activity directly linked to this vehicle family.