Soyuz TM-21 was a crewed Soyuz spaceflight to Mir. The mission launched from Baikonur Cosmodrome, atop a Soyuz-U2 carrier rocket, at 06:11:34 UTC on March 14, 1995. The flight marked the first time thirteen humans were flying in space simultaneously, with three aboard the Soyuz, three aboard Mir and seven aboard Space Shuttle Endeavour, flying STS-67. The spacecraft carried expedition EO-18 to the space station. This included the first American astronaut to launch on a Soyuz spacecraft and board Mir, Norman Thagard, for the American Thagard Increment aboard the station, which was the first Increment of the Shuttle-Mir program. The three crew members it launched were relieved by Space Shuttle Atlantis during STS-71, when they were replaced by expedition EO-19. The crew returned to earth aboard Soyuz TM-21 on September 11, 1995. Crew Mir Principal Expedition 18 The major objectives of the Mir 18 mission were to conduct joint U.S.-Russian medical research and weightlessness effects investigations and to reconfigure the station for the arrival of the Spektr science module and the Space Shuttle Atlantis. The historic mission saw the addition of the first new module (Spektr) since Kritall arrived in 1990, the first American (Thagard) to be part of a Mir crew, and the first docking of a U.S. spacecraft with the Mir space station. March 1995 - Mir 18 Arrives/Mir 17 Departs Progress M-26 Undocks for Soyuz TM-21 to Dock Progress M-26 separated from the complex on March 15 and made a destructive reentry into the Earth's atmosphere to clear the Kvant docking port for the new Soyuz. Soyuz TM-21 docked by automatic control at the Kvant docking port on the first try at 7:45 UTC on March 16. The new arrivals were greeted by the Mir 17 crew with the traditional Russian gifts of salt and bread, and shortly thereafter were congratulated on a successful docking and transfer by Russian Space Agency (RSA) Director General Yuri Koptev and NASA Associate Administrator Wayne Littles. The crew spent much of the day transferring equipment and supplies from Soyuz to Mir. Norman Thagard spoke with STS-67 Commander Steve Oswald in a radio hookup, exchanging congratulations on their respective flights and discussing the symbolic importance of Thagard's venture as the first American to visit Mir. On March 17, Russian Prime Minister Viktor Chernomyrdin stopped by the TsUP to congratulate the crew. Later, in a televised communication with ground controllers, Thagard said he