Lockheed Martin Space Systems of Sunnyvale, Calif., was awarded a $424.7 million contract from the U.S. Air Force to produce the fourth Space Based Infrared System (SBIRS) geosynchronous satellite, the U.S. Defense Department announced Jan. 7.

SBIRS prime contractor Lockheed Martin has been toiling with the program for more than a decade and hopes to soon deliver the program’s first dedicated geosynchronous satellite for launch in April. The company has delivered two SBIRS payloads that are hosted on classified satellites in highly elliptical orbits.

The Air Force in July 2009 issued a $262.5 million contract to Lockheed Martin to begin procuring long-lead parts for the fourth geosynchronous satellite in advance of a full procurement contract. The company is now under contract to produce a total of four SBIRS geosynchronous satellites and four SBIRS hosted payloads.