Repair Efforts Continue on Atlantis Shuttle's Dinged Fuel Tank

Engineers continueto work feverishly to repair the hail-damaged fuel tank of NASA's Atlantis shuttlein time for a mid-May launch, though space agency officials are still unsurewhether a replacement may be required.

"We stilldon't know which tank we'll use for STS-117," William Gerstenmaier, NASA'sassociate administrator for space operations, told a senate subcommittee thisweek of Atlantis' mission. "We can still potentially make the May launch windowif we use this tank, if we don't we'll be in the June time frame."

NASAofficials have said that Atlantis could launch between mid-May and May 21 ifthe shuttle'sfuel tank repairs, and a subsequent analysis, go well. Replacing the tank witha new one would push the spaceflight to no earlier than June 8.

NASA isexpected to set a new launch target for Atlantis' STS-117 mission to the International SpaceStation (ISS) on April 10.

The shuttleand its six-astronaut crew were preparing for a planned March 15 liftoff fromNASA's Kennedy Space Center (KSC) in Florida when a severe storm battered theorbiter's foam-covered fuel tank with golf ball-sized hail on Feb. 26.

Theresulting damage leftthousands of dings in the vital foam insulation on Atlantis' external tank,which engineers have been sanding smooth and repairing inside NASA's cavernousVehicle Assembly Building at KSC. Of the more than 2,500 dings in the fueltank, some 1,600 may require repair, NASA officials have said.

"It's goingto be very challenging," George Diller, a NASA spokesperson at KSC, told SPACE.comof the time-consuming repair work. "There's a lot of work to do, but it's achievable."

A new shuttle fuel tank, originallybuilt for NASA's STS-118 shuttle flight but which could be used for STS-117,will be shipped on Sunday or Monday from the agency's New Orleans-based MichoudAssembly Facility, NASA officials said. It will arrive two days earlier thanexpected at KSC in Cape Canaveral, Florida, they added.

"We'reexpecting the next tank on [April] 8 if they don't run into weather that slowsthem down en route," Diller said. "However, that is not going to speed thedecision process any...the tenth is still decision day."

Gerstenmaiersaid that it will be the repair work's progress that will dictate when shuttlemission managers will target Atlantis' launch date.

"We'reletting the work kind of drive the activity," Gerstenmaier said. "We're not pickingthe launch date and then forcing the work to fit into that launch date."

Commandedby veteran shuttle flyer Rick Sturckow, NASA's STS-117mission is the first of several ISS construction flightsscheduled for 2007. The 11-day flight features three planned spacewalks to installtwo new trusses and solar arrays to the station's starboard side.

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