Sixth Atlantis flight. Classified Department of Defense mission. Landed March 4, 1990 at Edwards Air Force Base, CA. Mission Duration: 106 hours 18 minutes 22 seconds.

Launch Date: February 28, 1990 Launch Vehicle: Atlantis Crew: Commander: John D. Creighton, Pilot:John H. Casper, Mission Specialists:David C. Hilmers, Richard M. Mullane, Pierre J. Thuot.