Space Shuttle Discovery alone. "Discovery" flew all three "return to flight" missions after the "Challenger" and "Columbia" disasters: STS-26 in 1988, STS-114 in 2005, and STS-121 in 2006. "Discovery" flew the ante-penultimate mission of the Space Shuttle program, STS-133, having launched on February 24, 2011. "Endeavour" flew STS-134 and "Atlantis" performed STS-135, NASA's last Space Shuttle mission. On February 24, 2011, Space Shuttle "Discovery" launched from Kennedy Space Center's Launch Complex 39-A to begin its final orbital flight. The Flow Director was responsible for the overall preparation of the shuttle for launch and processing it after landing, and remained permanently assigned to head
Space Shuttle external tank Space Shuttle external tank A Space Shuttle external tank (ET) was the component of the Space Shuttle launch vehicle that contained the liquid hydrogen fuel and liquid oxygen oxidizer. During lift-off and ascent it supplied the fuel and oxidizer under pressure to the three Space Shuttle Main Engines (SSME) in the orbiter. The ET was jettisoned just over 10 seconds after MECO (Main Engine Cut Off), where the SSMEs were shut down, and re-entered the Earth's atmosphere. Unlike the Solid Rocket Boosters, external tanks were not re-used. They broke up before impact in the Indian Ocean (or Pacific Ocean in