NASA?s shuttleAtlantis is on track for an early February launch toward the InternationalSpace Station (ISS) after two months of delay to repair a suspect fuel tankconnector.
Atlantis isslated to launch Feb. 7 on an 11-day missionto deliver the European-built Columbus lab to the ISS, though the finalapproval for the space shot will be discussed on Wednesday, NASA officials said Friday.The mission has been delayedsince early December, when fuel gauge-like engine cutoff (ECO) sensors inAtlantis? fuel tank failed standard countdown checks.
Engineers trackedthe problem to a suspect electrical connector at the bottom of Atlantis?15-story fuel tank. The super-cold temperatures of the shuttle?s cryogenicliquid hydrogen propellant stored in the tank may have led to open circuits inthe connector, which hassince been replaced with a new, modified design.
?We?re continuingto track toward Feb. 7,? NASA spokesperson Kyle Herring, of the Johnson SpaceCenter in Houston, told SPACE.com late Friday after a shuttleprogram-level readiness review. ?Everybody has a fairly high degree ofconfidence in the troubleshooting and testing that?s been done on the ECOsensor connector, and the repair work.?
Shuttleengine cutoff sensors are designed to serve as a backup system to shut down anorbiter?s three main engines before their fuel tank runs dry. If the enginescontinue to run on an empty tank, they could cause catastrophic damage, NASAofficials have said.
NASA?sflight rules call for three of the four sensors to operate properly beforeattempting a launch, though mission managers tightened the guideline up to four-of-four good sensors on a one-timebasis for the second of Atlantis? two launch attempts last month. Shuttlemanagers plan to return to the standard three-of-four rule for the upcomingFebruary launch, with a final decision to be made during the Wednesday meeting, spaceagency officials said.
Shuttleworkers, meanwhile, have returned to their normal preflight preparations aftercompleting the repair work at NASA?s Kennedy Space Center spaceport in Cape Canaveral, Fla., where Atlantis stands atop its Pad 39A launch pad.
?We?re notdealing with any hardware issues or personnel issues that would stand in theway or hold up the launch,? said KSC spokesperson Allard Beutel, adding that mostshuttle work teams are able to take the weekend off in the wake of the fueltank fix.
While NASAshuttle managers conduct their final review of Atlantis? launch readiness onWednesday, spacestation commander Peggy Whitson and flight engineer Dan Tani are expectedto step outside the orbital laboratory on a spacewalk to replace a suspectsolar array joint motor. NASA officials will discuss the results of bothactivities during separate briefings on Jan. 30.
Commandedby veteran shuttle flyer Stephen Frick, Atlantis? STS-122 mission will deliverthe space station?s Columbus lab for the European Space Agency (ESA) and swapout one member of the outpost?s three-person Expedition 16 crew. Thespaceflight is the first of five shuttleflights planned for this year.
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