Orbital and Aerojet Set to Begin AJ26 Rocket Engine Testing

• Arrival of "Pathfinder" Engine to Kick Off Three-Month Testing Process for Taurus II First Stage Propulsion System

(Dulles, VA., February 24, 2010) -- Orbital Sciences Corporation (NYSE: ORB) and Aerojet, a GenCorp (NYSE: GY) company - two of the world's leading space technology corporations - today announced the initiation of the AJ26 rocket engine testing process for Orbital's Taurus(r) II medium-class launch vehicle with the delivery of a "pathfinder" engine to NASA's Stennis Space Center in Mississippi. The AJ26 is Aerojet's liquid-fuel rocket engine that Orbital will use to power the first stage of the Taurus II space launch vehicle currently in development. The pathfinder engine will be used to verify test stand interfaces, engine handling processes, and test configurations prior to the commencement of the series of "hot fire" tests that are planned to begin in April.

"Our team is very excited to begin the ground testing of the AJ26 engine here at Stennis, one of the great rocket engine testing facilities in the world," said Mr. J.R. Thompson, Orbital's President and Chief Operating Officer. "We have worked with NASA's Stennis staff and our Aerojet partner to develop and install facility upgrades to accommodate our particular needs, and we are pleased with the results. Each of the AJ26 engines that will be used aboard our Taurus II rocket will come through the Stennis facility for pre-launch acceptance testing prior to being integrated with the rocket. We expect this extensive testing process and related activities will provide the Stennis Space Center with a meaningful boost in on-site activity."


Aerojet's Vice President of Space Programs, Ms. Julie Van Kleeck, said, "Aerojet is proud to be taking this important step toward the first flight of Orbital's Taurus II rocket. We understand the importance of the commercial launch industry and are proud to be a part of it."

Source : Orbital Sciences Corp.