The U.S. Air Force announced has tasked General Dynamics and Northrop Grumman Corp. to develop potential alternatives over the next 18 months to the Space Based Infrared Systems (SBIRS) High missile launch warning satellite.

Under contracts valued at $23.3 million and $24.8 million, respectively, General Dynamics and Northrop Grumman will work until May 2008 under the Alternative Infrared Satellite System (AIRSS) initiative, sister publication Defense Daily reported. The initiative is intended to mature modern infrared sensor components such as state-of-the-art focal plan arrays that the service may opt to pursue in place of building a full constellation of SBIRS High satellites that use the current design.

"Both contractors will evaluate space and ground system integration approaches for geosynchronous and potentially highly elliptical orbit (HEO) applications," stated the Air Force’s Space and Missile Systems Center (SMC), which let the contracts Dec. 4.

General Dynamics’ and Northrop Grumman’s activities will include a system requirements review of their respective concepts, a system design review, and contract deliverables that will refine their proposed AIRSS solutions, according to SMC.

The center said the companies’ work will provide the Air Force with the cost, schedule and technical insights required to proceed around mid 2008 with a request for proposals to industry to build the AIRSS, should the service opt to do so.

The Air Force launched AIRSS in 2005 as a risk mitigator in case the course of the SBIRS High satellite program, which has been derailed in the past due to technical and integration challenges, comes unglued again.

Raytheon and SAIC also are pursuing sensor concepts under AIRSS.

Lockheed Martin leads the industry team building the SBIRS High satellites, with Northrop Grumman serving as its sensor provider.

In addition to alerting the U.S. military to the launch of ballistic missiles of theater and strategic ranges, the sophisticated SBIRS High spacecraft are designed to support missile defense and supply technical intelligence and battlespace information for military commanders. These satellites will replace the Defense Support Program constellation.

This broad set of demands is one of the reasons that the program has faced setbacks, Air Force officials have said. But despite its checkered past, Air Force officials have said the SBIRS High program now is progressing well.

The first of two SBIRS High sensor payloads that reside on classified intelligence satellites in HEO is already in space and has completed an initial phase of on-orbit checkout, performing well to date, according to the Air Force. The second HEO payload has been delivered to integration with the classified host satellite.

Lockheed Martin is also under contract to build two SBIRS High satellites that will operate in geosynchronous Earth orbit. The first of these is slated for launch in 2008.

The Air Force is considering transitioning from SBIRS High to AIRSS after the second GEO spacecraft. Originally the Air Force planned to build up to five SBIRS High GEO satellites.

Under Secretary of the Air Force Ronald Sega said last week the Air Force is still determining how best to incorporate the technologies that result from AIRSS. Options still in the mix include going with a new AIRSS satellite or incorporating the technologies onto the third SBIRS High GEO spacecraft.

Even if the SBIRS High program does not encounter additional setbacks, it is desirable to be able to insert newer sensing technologies as quickly as is possible, and the AIRSS work will help to enable that, Air Force officials have said.