Shuttle engine test preps under way

Preparations for a key prelaunch engine test are under way at Kennedy Space Center today as NASA marches toward the planned July 1 launch of Discovery on the agency's second post-Columbia test flight.

The Flight Readiness Test involves gimbaling the engines and cycling valves within them. The idea is to make certain the engines can be steered in flight and that valves open and shut when commanded to do so.

Set for Tuesday, the test will follow checkout this past weekend of the shuttle's three Auxiliary Power Units. The units provide the hydraulic power needed to steer the shuttle's main engines in flight and operate its wing flaps, rudder speedbrake, landing gear and nosewheel steering system during atmospheric reentry and landing.

All three units passed the routine prelaunch checkout.