A smooth countdown culminates in an on-time liftoff as the Space Shuttle Columbia climbs skyward atop a column of flame. The launch from Pad 39B occurred at 3:18:00 P.M. EST, February 22, 1996. Aboard for Mission STS-75 is an international crew headed by Mission Commander Andrew M. Allen; Scott J. "Doc" Horowitz is pilot; Franklin R. Chang-Diaz is payload commander. Serving as mission specialists are Jeffrey A. Hoffman, Maurizio Cheli and Claude Nicollier. Cheli, from Italy, and Nicollier, from Switzerland, both represent the European Space Agency (ESA). Assigned as payload specialist is Italian Umberto Guidoni, who represents the Italian Space Agency (ASI). During a mission scheduled to last nearly 14 days the flightg crew will be working with two primary parylods: the U.S./Italian Tethered Satellite System (TSS-1R), which is being re-flown, and the U.S. Microgravity Payload (USMP-3), making its third spaceflight. Mission STS-75 marks the second Shuttle flight of 1996 and the 75th Shuttle launch overall.