Rocket engine passes hot-fire test

HANCOCK COUNTY — Pratt & Whitney Rocketdyne has completed the initial step in certifying the RS-68A rocket engine by successfully hot-fire testing the first certification engine. The RS-68A is an upgrade of the RS-68, a liquid-hydrogen/liquid-oxygen booster engine that will provide increased thrust and improved fuel efficiency for the Delta IV family of launch vehicles.

During the hot-fire test at Stennis Space Center, the first RS-68A certification engine successfully burned for 190 seconds, with operating time split between 102 percent and 55 percent power levels. Pratt & Whitney Rocketdyne will hot-fire test the first RS-68A certification engine a minimum of 12 times through February and follow that with a similar series of hot-fire tests on its second certification engine in March and April. Engine design certification review and acceptance of flight readiness are currently planned for July 2010.

Like the RS-68, three RS-68A engines will be used to boost a Delta IV Heavy rocket, but each RS-68A engine will provide 702,000 pounds of thrust, or 39,000 more pounds of thrust than a single RS-68 engine.