The U.S. Air Force and Lockheed Martin Space Systems on Nov. 15 successfully completed the critical design review for the third and fourth Space Based Infrared System (SBIRS) geosynchronous satellites, the service announced Nov. 23.
The long-delayed SBIRS constellation will be made up of multiple dedicated geosynchronous SBIRS satellites and SBIRS payloads hosted on classified satellites in highly elliptical orbits. Two of the highly elliptical orbiting payloads are now operating, and the government-industry team is hustling to ready the first geosynchronous satellite for a small launch window in April 2011.
More than 130 contractors and government workers took part in the critical design review for the third and fourth SBIRS spacecraft at Lockheed Martin’s Sunnyvale, Calif., facilities, the press release said. The corresponding payloads are now in production after passing critical design review in November 2009 at the Azusa, Calif., facilities of subcontractor Northrop Grumman Electronic Systems.
The third and fourth SBIRS satellites, planned for launch in 2014 and 2015, are “near clones” of the first two, the press release said. Minor changes include the use of new star trackers and inertial measurement units as well as replacements for parts that are no longer in production.