Team Will Simulate a Countdown, Liftoff by Space Shuttle Discovery

A countdown test will be conducted today in a major rehearsal for the first space shuttle launch since the Challenger disaster.

The launch team will assemble in the control center for the final three hours of a simulated countdown, with a mock liftoff of shuttle Discovery planned for 9:50 a.m. The exercise will be a realistic preparation for the actual launch, set for Aug. 31.

After the countdown, mission control center in Houston will assume control of a make-believe flight and will guide a shuttle crew, operating in a Houston simulator, through an abort situation in which the astronauts make an emergency landing at Kennedy Space Center.

The participating astronauts will be Loren Shriver, James Wetherbee and Franklin Chang-Diaz. Observing will be the five-man crew that will fly Discovery, commanded by astronaut Rick Hauck.

The launch team here has held countdown rehearsals every month for several months, but today’s test will be the first to tie together the Kennedy and Johnson space centers, the mission management team and all the other elements that will be in place on launch day.

National Aeronautics and Space Administration spokeswoman Lisa Malone said the practice “will validate to the fullest extent possible the complete launch process system.” She said it will exercise procedure and personnel changes that have occurred since the Challenger exploded 73 seconds after liftoff on Jan. 28, 1986, killing the seven crew members.