SACRAMENTO, Calif., May 18, 2011 – Aerojet, a GenCorp (NYSE: GY) company, announced today that its engines contributed to Space Shuttle Endeavour’s (STS-134) on-orbit operation and successful docking to the International Space Station (ISS). Endeavour lifted off on May 16 from NASA’s Kennedy Space Center in Florida and docked with the ISS this morning.

During the 14-day mission, Endeavour will deliver the Alpha Magnetic Spectrometer (AMS) and spare parts to the International Space Station, including two S-band communications antennas, a high-pressure gas tank and additional spare parts. The mission will feature four six-hour spacewalks to perform maintenance work and install new components. The STS-134 mission is Endeavour’s final launch and the next to last mission for the space shuttle program.

Since the initial shuttle launch in 1981, Aerojet’s Orbital Maneuvering System (OMS) engines and the Reaction Control System (RCS) thrusters have flown on every shuttle mission since its inception 30 years ago, as well as gas generators supporting the Auxiliary Power Units. The two OMS engines are used to place the shuttle into orbit and return it to Earth. The 38 primary and six Vernier RCS thrusters are used for attitude control during flight operations such as payload insertions and ISS docking.

“For the past three decades, Aerojet has been a partner with NASA and several DoD agencies on dozens of critical missions,” said Vice President, Space and Launch Systems, Julie Van Kleeck. “As the shuttle program comes to a close, we recognize all that it has brought to mankind over the years.”

Aerojet is a world-recognized aerospace and defense leader principally serving the missile and space propulsion, defense and armaments markets. GenCorp is a leading technology-based manufacturer of aerospace and defense products and systems with a real estate segment that includes activities related to the entitlement, sale, and leasing of the company’s excess real estate assets. Additional information about Aerojet and GenCorp can be obtained by visiting the companies’ websites at and