NASA Sets Discovery Liftoff for Monday, Ahead of Columbia

NASA will attempt to launch the shuttle Discovery on an atmospheric research mission next week, pushing the shuttle Columbia’s German-sponsored science flight into late April, officials said Tuesday.

If all goes well, Discovery would lift off at 10:32 p.m. PDT Monday on the eight-day flight. A nighttime launch is necessary to catch orbital sunrises and sunsets at the right spots for ozone measurements.

Columbia was supposed to be the next shuttle launched, but a stuck valve caused a main engine shutdown three seconds before liftoff on March 22. National Aeronautics and Space Administration officials said Tuesday that Columbia will be launched no earlier than April 24.

The same kind of engine valve failed in testing on Discovery over the weekend, and NASA replaced the bad component. Discovery’s other engine valves tested correctly, spokesman George Diller said.

Diller said engineers have not found a connection between the two failed valves. A piece of non-metallic debris, slightly more than one-tenth of an inch long, was blamed for Columbia’s stuck valve. Both valves were sent for analysis to main engine maker Rocketdyne, a division of Rockwell International.