The postponement of the launch of the Russian Service Module "Zvezda" to July 2000 led to the decision by NASA in February to split Space Shuttle mission STS-101 / 2A.2 into two separate missions (2A.2a and 2A.2b). The plan distributed the original STS-101 mission objectives between two flights, STS-101 and STS-106. With both missions slated for flight aboard Shuttle Atlantis, a modified STS-101 crew was named to prepare the Space Station for the arrival of "Zvezda".

The new STS-101 crew would be Commander Jim Halsell, Pilot Scott Horowitz, and Mission Specialists Mary Ellen Webber, Jeffrey Williams, James Voss, Susan helms and Yuri Usachev. (Voss, Helms and Usachev are the prime crew for main-expedition No.2 to ISS).

Astronauts on the new STS-106 mission will complete service module support tasks on orbit, transfer supplies and outfit ISS for the first long-duration crew. The STS-106 crew includes Commander Terrence Wilcutt, Pilot Scott Altman, and mission specialists Dan Burbank, Ed Lu, Richard Mastracchio, Yuri Malenchenko, and Boris Marukov. STS-106 will be launched after the Service Module is docked to ISS. If the SM fails to dock and the Interim Control Module (ICM) must be launched, STS-106 will swith from 2A.2b to 2A.3, and will fly the ICM mission, with the same crew, (probably in December 2000), minus the two russians. The two Russian cosmonauts have trained specifically on SM systems, so there would be no reason to take them up on the ICM flight.

This was a very rare decision by NASA to replace astronauts of a crew already in training. Before STS-51L it happened a lot but from STS-26 on almost all crews flew as selected. Shown below are some photographs of the STS-101 crew training for their Space Staion flight.

The old (left) and new (right) crew patches for mission STS-101. the sevice module and progress are left out on the new patch, (STS-101 will only be visiting the FGB and Unity). Also the names of the crewmembers have been updated. Note also that 101 was added behind the Shuttle.

The old crew (left) and the new STS-101 crew (right).

Left:RSC-energia personel brief members of the original STS-101 crew on the hydrolab mock-up version of the service module. Ed Lu on the stairs and Jeffrey Williams were supposed to make an EVA on STS-101 to inspect the SM after it had docked to the FGB.

Right: A mock-up of the service module and Functional Cargo Block, of ISS, at the Gagarin Cosmonaut Training Center in Star City, Russia. the mok-ups are joined to the floor of the hydrolab, wich can be lowerd down, for EVA training.

Left: Cosmonaut Yuri Usachev lays on his back in the crew Compartment Trainer (CCT-2) where he is rehearsing Shuttle vertical-mode emercency egress procedures.

Right: Astronaut Susan Helms prepairs to enter CCT-2 at JSC's System Intergration Facility, to participate in a Shuttle vertical-mode emergency egress procedure.