File:KSC-05-S-00075 (ksc 032505 sssr).webm

English: Now on the NASA Space Shuttle Status Report: Date for a mate: orbiter Discovery is just days away from rollover to the VAB for final Return to Flight preparations. Double dose: STS-121 is also on NASA's radar as Atlantis hits two milestones_ Plus, moving right along: Endeavour inches back to the Orbiter Processing Facility after a brief trip away from home. I'm Tim Potter, NASA test director, and this is the NASA Space Shuttle Status Report. As the calendar closes in on the month of April, NASA's Return to Flight plans are full speed ahead. Our big story this week: technicians are making final preparations for Discovery's rollover_ With final systems checks nearing completion, orbiter Discovery is set to rollover to the Vehicle Assembly Building at the Kennedy Space Center on or about March 28. Inside the VAB, Discovery will be bolted to its External Tank and Solid Rocket Boosters. When mating is complete, the Crawler Transporter will roll the flight stack out to Launch Pad B about a week later. Meanwhile, in the Space Station Processing Facility, Discovery's payload is being readied for flight. The Multi-Purpose Logistics Module, which is like a huge suitcase, has been filled with all the stowage racks that carry all the supplies necessary for living and working on the International Space Station. The MPLM hatch is scheduled to close in mid-April. In addition, a replacement Control Moment Gyro, or CMG, was also readied for the upcoming mission. The astronauts will exchange an inoperable CMG with this new one with a spacewalk during STS-114, NASA's Return to Flight mission to the ISS. Space Shuttle Atlantis is being prepared for STS-121, its mission to the ISS. Its Space Shuttle Main Engines are being readied for installation the first week in April, and Atlantis' External Tank arrived at the Launch Complex 39 Area Turn Basin March 15. The tank was transported to the VAB, where it is now undergoing final processing in the checkout cell. In February, orbiter Endeavour was rolled from its Orbiter Processing Facility to the Florida Space Authority's Reusable Launch Vehicle hangar at Kennedy Space Center to undergo testing to see how orbiters respond to a new radar system that will be used to detect debris during launch. During Endeavour's absence, open bay maintenance and modifications were performed. Endeavour has now been returned to the OPF to continue ground processing activities for its next mission. That's all the time we have for this week's Space Shuttle Status Report. Be sure to mark your calendars for May 15 to June 3, NASA's official window for Space Shuttle Discovery's Return to Flight mission, designated STS-114 to the International Space Station. Until next time, log on to nasa.gov for the latest in Return to Flight and NASA mission news. I'm Tim Potter for the NASA Space Shuttle Status Report.