Aerojet has successfully completed verification testing of its HOPE-X Orbital Maneuvering Engine (OME),
qualifying it for operation as the main propulsion for the Japanese National Space Development Agency’s HOPE-X vehicle.

The HOPE-X vehicle is a prototype unmanned shuttle to be launched by Japan’s HIIA launch vehicle. Aerojet is developing the HOPE-X OME for
Ishikawajima-Harima Heavy Industries Company, the shuttle’s propulsion system contractor.

The reusable HOPE-X OME is a 4,000-pound-force thrust class engine that is pressure-fed, regeneratively cooled and operated with storable propellants. It is
much like the space shuttle Orbital Maneuvering System, also designed and built by Aerojet, which has delivered 100 percent mission success on every shuttle

“The HOPE-X engine program represents another successful activity in our continuing long-term relationship with Ishikawajima-Harima Heavy Industries
Company and the National Space Development Agency of Japan. I congratulate the entire IHI/Aerojet team for completing qualification of the OME in exemplary
fashion,” said Bob Harris, Aerojet vice president of Propulsion and Armament Systems.

The HOPE-X OME verification program, consisting of 19 engine firings at simulated altitudes above 100,000 feet, met all technical objectives and customer
expectations. The firings predominantly were 20 seconds to verify engine operation over a large range of propellant inlet conditions. The testing was concluded
with a one-hour mission duty cycle firing and a six-minute duration firing.

The test engine will be refurbished and delivered to the customer as a flight spare in addition to the two new flight engines which are now ready for acceptance
testing and delivery later this year.

This test program also marked the successful re-activation and operation of the Aerojet J-4 Altitude Test Facility, which had been unused since 1993. The 19
engine firings were conducted over three weeks from December 1999 to January 2000. During that period as many as three tests per day were achieved with a
minimum test crew.

Aerojet, a GenCorp company, is a world-recognized aerospace and defense leader principally serving the space electronics, missile and space propulsion, and
smart munitions and armaments markets. Aerojet’s Web site address is