NASA Clears Fuel Tank Concerns for Shuttle Launch

Thisstory was updated at 7:00 p.m. EDT.

Top NASAofficials have cleared the space shuttle Discovery?s external fuel tank of anyconcerns related to its foam insulation, setting the stage for a Wednesdaymeeting expected set an official launch date of Aug. 25.

NASAshuttle managers and engineers hoped to set the launch date for Discoveryduring a day-long Tuesday meeting at the agency?s Kennedy Space Center inFlorida. But the meeting ran long, forcing them to reconvene Wednesday to wrapup their flight readiness review after deciding late today that Discovery?sfuel tank is safe to fly.

An announcementon NASA?s Twitter page stated that mission managers completed reviewing datafrom recent fuel tank tests to check the foam insulation on Discovery?s tank,finding it good to launch ?as is.? NASA engineers spent hours discussing concernsover the fuel tank after an excessive amount of foam debris was seen during arecent shuttle launch.

?There?sobviously a lot of thorough discussion going on,? said Allard Beutel, a NASAspokesperson at the Florida spaceport, shortly before Tuesday?s meeting ended.?They?re making sure that everybody gets the opportunity to present theirside.?

Beutel toldSPACE.com that Discovery is currently slated to launch no earlier than Aug. 25,one day later than an earlier target, due to delays associated with weekendfuel tank tests. Liftoff for that Tuesday target would occur at 1:36 a.m. EDT(1736 GMT), if approved.

Discovery?sseven-astronaut crew is slated to fly a 13-day mission to the InternationalSpace Station to deliver a new crewmember, vital supplies and a treadmillnamed after comedianStephen Colbert, among other gear. Three spacewalks are planned.

Fueltank concerns

The debateover Discovery?s readiness to fly hinged on its foam-covered fuel tank.

NASA haskept a close watch on the amount of foam debris that occurs during shuttlelaunches since 2003, when a piece of foam damaged the Columbia orbiter?s heatshield and led to its destruction during re-entry. Sevenastronauts were killed in the disaster.

Last month,an unusually high amount of foam fell from the shuttle Endeavour?s fuel tankduring its June 15 launch. The foam separated from an unexpected region calledthe intertank, a ridged section of the 15-story tank just above its mid-point,but ultimately posed no risk to Endeavour or its crew.

But NASA wantedto be sure that a similar foam event won?t occur during Discovery?s launch andpose a threat to the shuttle. A team of engineers performed a second round ofpull tests on the shuttle?s fuel tank over the weekend to make sure it wassecure.

Engineersalso analyzed X-ray results on foam-covered brackets called ice-frost rampssimilar to those on Discovery?s tank. Foam fell from a similar ice-frost rampduring recent shuttle launches as well, so the engineers scanned a fuel tank tobe used on a November shuttle flight to check for any generic flaws.

Thepreliminary results from both tests suggested Discovery is clear to launch nextweek on its mission to the International Space Station. But NASA officials wantto be sure they completely reviewed the available information before making afinal decision, which prolonged Tuesday?s launch date discussion, Beutel said.

Because ofthe lengthy round of fuel tank tests, mission managers were ready for a long discussionto be sure Discovery is ready and safe to fly, he added.

?If ithappens to go into extra innings, then so be it,? Beutel said.  

NASA mustlaunch by Aug. 31 to avoid conflicting with an unmanned Japanese cargo shipalso headed for the station on Sept. 10. The next assured launch window afterthis month opens Oct. 17.

If missionmanagers do select an Aug. 25 launch date for Discovery, the shuttle?sastronaut crew will fly into the Kennedy Space Center from Houston lateWednesday, Beutel said.

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