KENNEDY SPACE CENTER, FL - Today, space shuttle managers cleared Endeavour for launch Wednesday on a space station construction mission, pushing back launch of an unmanned mission to the Moon in order to accomodate the shuttle's delayed liftoff and maximize the launch windows for both spacecraft which run only until June 20.
VIDEO: STS-127 COUNTDOWN STATUS BRIEFING - JUNE 15 VIDEO: TECHNICIANS WORK TO REPAIR THE ET GH2 GUCP VIDEO: LRO MISSION B-ROLL VIDEO VIDEO: LRO - NASA MISSION TO THE MOON VIDEO: LRO/LCROSS PRELAUNCH PRESS CONFERENCE VIDEO: LRO/LCROSS SPACECRAFT MOVED TO THE LAUNCH PAD Endeavour's countdown was halted hours before launch last Saturday when a seal around a gaseous hydrogen vent line developed a potentially dangerous leak of the highly flammable gas. The leak resulted in a scrub of the launch attempt and NASA developed a plan to replace the seal and target a new launch date this week. Endeavour's launch window on Wednesday opens at 5:35:50 a.m. EDT, and the shuttle's liftoff time is tartegeted for the middle of the window at 5:40:50 in order to maximize the performance of the vehicle. NASA's Lunar Reconnaissance Orbiter / Lunar Crater Observation and Sensing Satellite (LRO/LCROSS) was originally penned in the Air Force Eastern Range's schedule for launch Wednesday. Over the weekend, shuttle program officials and their counterparts in the LRO project and builder of the spacecraft's Atlas 5 rocket, United Launch Alliance, held negotiations leading LRO to giving up the first day of their four day launch window, which runs from June 17 to June 20. Endeavour will have one opportunity, the 17th, to get off the ground and then will stand down for LRO to take the remainder of the window. If technical problems, weather or some other event keeps the shuttle on the ground, it could be July 11 before the next launch opportunity. "The agreement we've made with the Range and the Atlas LRO folks is that we will have one opportunity on the 17th and then stand down and allow them to play through," said NASA Test Director Steve Payne. With repair work on the gaseous hydrogent vent line seal proceeding well, NASA aims to pick up the shuttle's launch countdown at 1:15 p.m. EDT on Tuesday at the T-11 hour mark. Fueling of the vehicle will begin around 8 p.m. and the hydrogen tank should reach 98% full and enter topping about three hours later. At that point, the vent valve will be cycled to test it's performance and NASA engineers will know for sure at that point whether or not the valve R & R work was successful. Meanwhile, preparations are proceeding for the launch of LRO/LCROSS, targeted for either Thursday for Friday. Because of range requirements and the time it takes to reconfigure equipment between launches, the Atlas rocket will likely blast off Friday evening at 6:41 p.m. EDT. However, NASA requested the Air Force to look into the possibility of supporting a 5:12 p.m. June `18 launch. "We spent the weekend talking with the shuttle program," Dovale said. "Just recently, we have met with them and we are relinquishing the June 17 launch date to them. They are tracking well to their re-work for the seal. We will maintain June 18 as the earliest capability for LRO/LCROSS and the Atlas 5. "We will monitor shuttle's progress. If shuttle were to begin their count and scrub for any reason prior to midnight, LRO/LCROSS and Atlas can maintain June 18 as the earliest date. Right now, the Range is working the question if shuttle launches on the 17th, can they still support us on the 18th? That's just about 24 to 28 hours of turnaround where they really require 48." If Endeavour's launch is scrubbed, the Atlas will make a launch attempt on the 18th. NASA and United Launch Alliance want to know if the Eastern Range could possibly support a launch on the 18th even if the shuttle does launch. That would challenge the Air Force's ability to perform a rapid turnaround of the range assets, but isn't out of the question. Even without the extra day, LRO/LCROSS will have at least two launch opportunities, on the 19th and 20th, before the window closes. Endeavaour has only the 17th to get off the ground or be forced to wait until at least July 11 because of thermal constraints on the space station that preclude having an orbiter docked from late June to early July. (The Spacearium / Space Media Corporation)
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