Shuttle Set For Another Launch Try
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By Frank Morring, Jr.
NASA will try again Wednesday, July 15 to launch the space shuttle Endeavour to the International Space Station, rearranging its assembly mission to avoid an end-of-mission conflict with an upcoming Russian resupply mission by undocking early.
Space station planners believe they can still accomplish all mission objectives by moving some cleanup and crew time off until after the orbiter undocks from the station. If a Wednesday launch attempt doesn't succeed, they may remove some mission objectives to undock early enough at the end of mission to allow a Thursday, July 16 launch.
Senior agency managers asked their Russian counterparts to delay the Progress docking after its scheduled July 24 launch to allow a later shuttle launch, according to Mission Management Team chairman Mike Moses. But the Russians had already allotted four days of loiter time before docking at the station to accommodate the shuttle delays, and said no to preserve a single contingency day beyond the four days already being used.
"They were willing to play ball," Moses said.
Crews at Kennedy Space Center will use Tuesday, July 14 to reattach a temporary thruster cover that had come loose, which will require closing the rotating service structure at Pad 39A back around the orbiter. Launch on Wednesday is set for 6:03 p.m. EDT.
The decision to rearrange "mission content" at the station came after a Monday, July 13 launch scrubbed, marking the third time since Saturday, July 11 that the STS-127 mission was delayed by summer thunderstorms at the Florida launch site. As the countdown moved toward the end of the final nine-minute hold, the pad was "red" for lightning within 10 nautical miles, violating launch constraints, and for thunderstorms within 20 nautical miles of the runway the orbiter would have to use in an unlikely but always possible return-to-launch-site abort.
The "field mill" rule setting limits on electrical fields that could trigger lightning during a launch also were in violation, and conditions were worsening when the scrub was called.
"The vehicle and our teams were ready, but the weather has just bitten us again," Launch Director Mike Leinbach radioed to the crew.
Weather conditions on Wednesday are expected to improve over Monday, Moses said.
The primary goal of the STS-127 mission will be to attach a porchlike exposed facility to Japan's Kibo laboratory module and install the first experiments on it.
The current mission timeline carries five spacewalks. In addition to connecting up the Kibo hardware, spacewalkers will install large spare parts on the station truss against the day when the shuttle is no longer flying, and replace the station's oldest set of batteries.
Endeavour is also scheduled to deliver Tim Kopra of NASA to his post as a station crewman, replacing Japanese astronaut Koichi Wakata. Wakata will return to Earth on Endeavour.
Endeavour photo: NASA