NASA
engineers have completed some repairs to the shuttle Atlantis' hail-damaged
external fuel tank at the agency's Florida spaceport, where a possible
replacement is due to arrive Friday, agency officials reported Thursday.
A barge
carrying the new shuttle fuel tank is expected to dock at NASA's Kennedy Space
Center in Cape Canaveral, Florida at about 1:00 p.m. EDT (1700 GMT), the space
agency said in a mission update, adding that initial
repairs to the vital foam insulation covering the lower half of Atlantis' damaged
tank are finished.
"Foam
repairs on the liquid hydrogen tank, which is located on the bottom of the external
tank, are complete," NASA reported. "The focus is currently on repairs to the
liquid oxygen tank."
The
shuttle tank's liquid oxygen supply resides in the upper portion of the fuel
vessel, where engineers have sanded away the damaged foam insulation and plan to
spray on new layer of material.
Atlantis'
fuel tank sustained thousands of dings during a freak Feb. 26 storm that
bombarded the 15-story vessel with golf ball-sized hail at the shuttle's Pad
29A launch site. The damage prompted NASA shuttle managers to delay
the planned March 15 launch of Atlantis' STS-117 mission to the International
Space Station (ISS) to allow time for repairs or an external tank swap.
Atlantis
is currently slated to launch its ISS construction mission no earlier than
mid-May if its tank can be repaired swiftly, though a fuel tank change would
push the flight into June.
"Right now
I know they're working hard to repair the tank at this time," STS-117
mission specialist Steven Swanson told SPACE.com Thursday, adding
that workers at NASA's New Orleans-based Michoud Assembly Facility -- where
shuttle fuel tanks are built -- are focused ensuring the fixes are sound. "The
engineers are working hard at Michoud on the certification of the repairs that
they're doing. So that should all hopefully come together some time next week
and we'll find out what we'll do."
NASA
managers are expected to meet around April 10 to decide whether or not to
proceed with a mid-May launch target or switch tanks and aim for June. Atlantis'
launch window in May closes around May 21 and reopens around June 8, NASA
officials have said.
Commanded
by veteran shuttle spaceflyer Rick Sturckow, Atlantis' STS-117 astronauts plan to
deliver a new pair of massive ISS trusses and solar arrays during their 11-day
construction mission.
Swanson,
who will perform one of three planned spacewalks during the STS-117 flight,
said the mission's delay has had a silver lining of sorts, allowing he and his
crewmates a short break from the frenetic pace of flight training.
"It's all
in stride, I think," said Swanson, who joined NASA's Astronaut Corps in 1998 and
will make his first spaceflight during STS-117, of the delay. "What's another
month of two after nine years?"
advertisement
