Twelfth Columbia flight. The First United States Microgravity Laboratory (USML-1) studied scientific and technical questions in materials science, fluid dynamics, biotechnology and combustion science. Landed July 9, 1992 at Kennedy Space Center, FL. Mission Duration: 331 hours 30 minutes 4 seconds. 

Launch Date: June 25, 1992 Launch Vehicle: Columbia Crew: Commander: Richard N. Richards, Pilot: Kenneth D. Bowersox, Mission Specialists: Bonnie J. Dunbar, Carl J. Meade, Ellen S. Baker, Payload Specialists: Lawrence J. DeLucas.