STS-40

STS-40, the eleventh launch of Space Shuttle Columbia, was a nine-day mission in June, 1991. It carried the Spacelab module for Spacelab Life Sciences 1 (SLS-1), the fifth Spacelab mission and the first dedicated solely to biology. STS-40 was the first spaceflight that included three women crew members.

Crew

Backup crew

Crew seating arrangements

Mission highlights

Launch originally set for 22 May 1991. Mission postponed less than 48 hours before launch when it became known that a leaking liquid hydrogen transducer in orbiter main propulsion system which was removed and replaced during leak testing in 1990, had failed an analysis by vendor. Engineers feared that one or more of the nine liquid hydrogen and liquid oxygen transducers protruding into fuel and oxidizer lines could break off and be ingested by the engine turbopumps, causing engine failure.

In addition, one of orbiter five general purpose computers failed completely, along with one of the multiplexer demultiplexers that control orbiter hydraulics ordinance and orbiter maneuvering system / reaction control system functions in the aft compartment.