Lockheed Martin recently held a competition to select a motor supplier following a May decision by Pratt & Whitney to exit that business.

In addition to supplying Orbus-1a motors, ATK also will provide thrust vector control systems to be used on the program. The contract also includes funds for test motors and ground and altitude qualification tests.

ATK will begin motor deliveries in the first quarter of 2006. Terms of the contract were not disclosed.

"We anticipate a smooth transition to ATK from Pratt & Whitney. I am confident that BV+ will be a reliable and effective contributor to the nation's first protection from long-range ballistic missile threats," said Linda Reiners, vice president - Missile Defense Systems, Lockheed Martin Space Systems Company.

"Teams from Lockheed Martin, ATK and Pratt & Whitney have been assembled to successfully transition and deliver the new motors to our customer on time."

The Boeing Company is the prime contractor for the Ground-based Midcourse Defense system.