NASA Clears Fuel Tank Concerns for Shuttle Launch

This story was updated at 7:00 p.m. EDT.

Top NASA officials have cleared the space shuttle Discovery?s external fuel tank of any concerns related to its foam insulation, setting the stage for a Wednesday meeting expected set an official launch date of Aug. 25.

NASA shuttle managers and engineers hoped to set the launch date for Discovery during a day-long Tuesday meeting at the agency?s Kennedy Space Center in Florida. But the meeting ran long, forcing them to reconvene Wednesday to wrap up their flight readiness review after deciding late today that Discovery?s fuel tank is safe to fly.

An announcement on NASA?s Twitter page stated that mission managers completed reviewing data from 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 concerns over the fuel tank after an excessive amount of foam debris was seen during a recent shuttle launch.

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

Beutel told SPACE.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 weekend fuel tank tests. Liftoff for that Tuesday target would occur at 1:36 a.m. EDT (1736 GMT), if approved.

Discovery?s seven-astronaut crew is slated to fly a 13-day mission to the International Space Station to deliver a new crewmember, vital supplies and a treadmill named after comedian Stephen Colbert, among other gear. Three spacewalks are planned.

Fuel tank concerns

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

NASA has kept a close watch on the amount of foam debris that occurs during shuttle launches since 2003, when a piece of foam damaged the Columbia orbiter?s heat shield and led to its destruction during re-entry. Seven astronauts were killed in the disaster.

Last month, an unusually high amount of foam fell from the shuttle Endeavour?s fuel tank during its June 15 launch. The foam separated from an unexpected region called the 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 wanted to be sure that a similar foam event won?t occur during Discovery?s launch and pose a threat to the shuttle. A team of engineers performed a second round of pull tests on the shuttle?s fuel tank over the weekend to make sure it was secure.

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

The preliminary results from both tests suggested Discovery is clear to launch next week on its mission to the International Space Station. But NASA officials want to be sure they completely reviewed the available information before making a final decision, which prolonged Tuesday?s launch date discussion, Beutel said.

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

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

NASA must launch by Aug. 31 to avoid conflicting with an unmanned Japanese cargo ship also headed for the station on Sept. 10. The next assured launch window after this month opens Oct. 17.

If mission managers do select an Aug. 25 launch date for Discovery, the shuttle?s astronaut crew will fly into the Kennedy Space Center from Houston late Wednesday, Beutel said.

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