Shuttle now carries 'repair kit'

For space shuttle astronauts, computer crashes and broken gyroscopes during flight have long been fixable glitches.

Now, on the Discovery flight, set to lift off as soon as this week, the crew will -- for the first time -- have a sturdy repair kit handy to plug holes in case the spacecraft's wings are punctured in transit.

Engineers at NASA/Ames Research Center gave the kits a rigorous workout, using a superheated tube called an Arc Jet to see if these patches can take the heat. Loose insulating foam that detached and pierced a hole in space shuttle Columbia's left wing caused the Feb. 1, 2003, disaster in which seven astronauts died. NASA experts say this could help fix a similar problem should it happen again.

``If you have a flat tire, you have a spare,'' Ernie Fretter, a mechanical engineer involved in the tests, said last week in the Arc Jet workshop. Before, if the shuttle hit a snag, crew members would be stuck or have to be rescued at the space station. ``You can't stuff space suits in the hole.''

The Arc Jet team's engineers and computer scientists are among 100 people at Ames who will be on call to help if something goes wrong with Discovery's mission. It is the first time since the National Aeronautics and Space Administration began launching space shuttles that Ames workers have been on deck to help during a flight, NASA officials say.

Other Ames employees will be running supercomputer simulations of the launch and also checking results of shuttle's aerodynamic behavior in the wind tunnel to see how parts operate in flight.

Discovery's launch, the first return to orbit since the Columbia disaster, has been delayed due to a fuel gauge malfunction.

Fretter said the Arc Jet engineers are thrilled to be involved.

``The other shuttle missions we watched on TV,'' said Fretter. ``Now, from the interns to the engineers, there is more anxiety that it works fine. But we are ready to do what it takes.''

The mending kit was developed by ATK Thiokol, an aerospace contractor based in Brigham City, Utah. To make sure their tools can withstand heat of re-entry, Ames engineers relied on the Arc Jet machine -- a 15-foot-long box of ``contained lightning'' with enough power to continuously heat 10,000 homes. The powerful machine has been used to test heat shields used on many spacecraft, such as the recently deployed Mars rovers and the old Viking probes that explored Venus. Inside, coils of cooling hoses adjust the temperature, which can heat materials up to 3,000 degrees Fahrenheit -- the temperature shuttles can reach as they re-enter Earth's atmosphere.

Into the giant flamethrower, the engineers dangle two instruments: a 4-inch-long crack repair kit made of reinforced carbon-carbon -- a dense, charcoal-like material resistant to very high temperatures that has been used on tips of ballistic missiles.

The cracked surface can be caulked by astronauts if tiny fissures appear. The other device is a flat, circular patch seven inches in diameter, which astronauts can use to plug a puncture in the spacecraft's nose or wing. Once aloft, Discovery's crew is set to conduct tests inside the cargo bay to see how well they can wield the tools in the vacuum of space.

Frank Hui, one of the Arc Jet aerospace engineers who has been running these experiments -- more than 70 tests in one year -- said his work feels personal to him. He knows Steve Robinson, a crew member on Discovery who used to work at Ames. Also, he was an intern at Ames during the 1986 Challenger disaster when seven astronauts died during a launch failure.

``It was horrendous,'' Hui said last week as he watched the Arc Jet's orange flame blast materials to be used on a future NASA flight to Mars. ``They are our buddies up there. We want to see them home and walking on the ground.''   link