SPACE.com -- Shuttle Atlantis Likely to Fly First, Cracked Plumbing to be Fixed by Welding

Shuttle Managers Narrow Repair Options, Consider Schedule

First Crack Found Within Columbia's Propulsion System Plumbing

Shuttle Columbia's Next Crew Take Research Mission Delay in Stride

Shuttle Schedule Uncertain as NASA Deals with Technical Problem


	Shuttle Atlantis Likely to Fly First, Cracked Plumbing to be Fixed by Welding By Jim Banke Senior Producer, posted: 05:00 pm ET 19 July 2002

CAPE CANAVERAL, Fla. -- Tiny cracks in the space shuttle's propulsion system plumbing will be repaired by welding and the next mission -- an International Space Station assembly flight -- could launch as soon as late September or early October.

That's the way NASA managers are leaning right now, shuttle program director Ron Dittemore said during a teleconference Friday.

"I believe the team will come forward next week and recommend we should do a repair, and they will recommend a weld-type repair," Dittemore said. He cautioned that there still is more analysis ahead before a final decision is made during a meeting scheduled for July 31. "Again, I would stamp preliminary on all of that."

If the plan as foreseen right now is approved, the repair effort could begin about Aug. 5. It would take a couple of days to complete the repairs and put the shuttle team in a position to finish countdown preparations in time to launch around Sept. 26, or possibly into the first week of October, Dittemore said.

As it stands now, the expected order of flights would have Atlantis launching first on a mission to install a new truss segment at the station. Endeavour would follow around Nov. 2 on a similar truss-delivery mission, but that flight also would feature a crew rotation.

Columbia's 16-day science research mission -- which includes Israel's first astronaut as a member of the crew -- would fly some time in December.

The tiny cracks were found on the surface of metal liners that are inside liquid hydrogen pipes located within each shuttle's rear engine compartment. The flaws are not within the Rocketdyne main engines themselves.

The liners help direct the flow of propellant through the plumbing and past accordion-shaped bellows that give the plumbing needed flexibility for when the supercold fuel causes the pipes to shrink.

The concern is that if the cracks were to grow during a launch and a piece of metal were to break free, the debris would be sent into the engine where it could cause a potentially catastrophic shutdown.

Last week officials narrowed their choice of repair options to three, and during the past week selected the welding option as the best one to pursue. The other two involved cutting metal away from the liners or drilling holes in the devices.

Dittemore said that after the repairs are made the parts will continue to be carefully inspected after each flight, and that engineers might consider redesigning the component in the future.

At the same time, engineers are continuing to search for the reason why the cracks happened in the first place -- something that NASA may need several more weeks, if not months, to determine.

"We're still searching for that elusive root cause. We're not there yet," Dittemore said. "But that's not going to hold us up from returning to flight."

	New Galapagos Expedition Offers Lindblad Expeditions Explore the Galapagos and save up to 25% off select departure dates www.Expeditions.com

	BP There’s energy security in energy diversity.

	One-stop destination for the lowest domestic airfares Search all airlines, including Southwest now!

	HP ProLiant Servers The HP portfolio of servers-leading technology that respects the bottom line. Powerful ProLiant technology at a price that's worth a second look.