While the final decision on adding an additional shuttle flight rests on the political process, today NASA managers approved adding the STS-135 mission, from a safety and logistics standpoint. If Congress gives final approval for funding one more shuttle mission beyond the two that are currently on the manifest, space shuttle Atlantis would be targeted to launch on June 28, 2011. The STS-135 mission – if not needed as a “Launch on Need” rescue flight for STS-133 or STS-134, would have a 4-member crew and carry a fully-loaded multi-purpose Logistics Module (MPLM) and a Lightweight Multi-Purpose Carrier to the International Space Station.
NASA’s Aerospace Safety Advisory Panel approved adding the flight from a safety standpoint. Having a crew of four means the crew – if stranded on the ISS – could stay on the space station and rotate coming back to Earth on the Soyuz spacecraft that serve as rides home/rescue vehicles , and NASA would not need another shuttle on standby for a rescue.
Originally, the Senate version of NASA’s 2011 budget included funding for an additional shuttle mission but the House version did not. However, NASASpaceflight.com reported that “The House authorization bill added the additional flight to mirror the Senate bill,” adding that the two bills differ in how the flight would be paid for.
Atlantis will be processed for the STS-335 Launch On Need mission, and the final decision on whether STS-135 becomes a reality remains to be seen. Stay tuned!