Prime contractor Lockheed Martin and payload provider Northrop Grumman have delivered the payload for the fourth Geosynchronous Earth Orbit (GEO) satellite of the U.S. Air Force's Space Based Infrared System (SBIRS).

The payload, delivered on Sept. 30, will now be integrated with the SBIRS GEO-4 satellite bus in final assembly, integration and test at Lockheed Martin's Sunnyvale, California satellite manufacturing facility.

The SBIRS program delivers timely, reliable and accurate missile warning and infrared surveillance information to the President of the United States, the Secretary of Defense, combatant commanders, the intelligence community and other key decision makers.

The system enhances global missile launch detection capability, supports the nation's ballistic missile defense system, expands the country's technical intelligence gathering capacity and bolsters situational awareness for warfighters on the battlefield.

The SBIRS GEO-4 payload includes highly sophisticated scanning and staring sensors, which will provide the satellite with improved infrared sensitivity and a reduction in area revisit times over the legacy constellation. The scanning sensor will provide a wide area surveillance of missile launches and natural phenomena across the earth, while the staring sensor will be used to observe smaller areas of interest with superior sensitivity.

"The completion of this payload is a critical milestone keeping us on schedule for delivering the SBIRS GEO-4 satellite to the Air Force in 2016," said Louie Lombardo, director of Lockheed Martin's SBIRS Follow-on Production (SFP) program.

"This payload delivery -- the third of four payload deliveries for the SBIRS SFP program in the past 15 months -- further demonstrates that SBIRS is in the regular cadence of full production."

"This is an unprecedented production rate of sophisticated infrared payloads for operational deployment," said Anne Ostroff, vice president of the Military/Civil Space and Ground business area, Northrop Grumman. "The performance of payloads on-orbit has been excellent and demonstrates unique capabilities that are needed to address current and evolving threats."

The SBIRS architecture includes a resilient mix of satellites in GEO, hosted payloads in Highly Elliptical Orbit (HEO), and ground hardware and software. The GEO-1 and GEO-2 satellites have been launched and both received Air Force Space Command Operational Acceptance in 2013, with performance that matches, and in some cases exceeds, requirements.

GEO-3 recently completed acoustic testing and is currently undergoing thermal vacuum testing. In June 2014, the Air Force contracted Lockheed Martin for full production of GEO-5 and GEO-6.

The SBIRS team is led by the Remote Systems Directorate at the U.S. Air Force Space and Missile Systems Center. Lockheed Martin is the SBIRS prime contractor, while Northrop Grumman is the payload provider. Air Force Space Command operates the SBIRS system.