There is a fundamental problem with the U.S. Air Force’s plan for the Alternative Infrared Satellite System (AIRSS) –

the service’s inability to clearly define the program or its place within the nation’s space-based missile warning architecture.

Is AIRSS a stop-gap replacement for the long-troubled Space Based Infrared System (SBIRS), or is it a follow-on system featuring next-generation technology and capabilities? Public statements to date indicate that the Air Force is not sure, or is trying to have it both ways.

In February, Air Force Col. Bob Newberry, the AIRSS program director, said that if SBIRS continues to flounder, an AIRSS system roughly equivalent in capability to the current Defense Support Program could be fielded relatively quickly to provide initial warning of missile launches. If, on the other hand, SBIRS rights itself, AIRSS could be repositioned as a more-capable follow-on system, he said.

That’s a lot of uncertainty for a program with a proposed 2008 budget

of $231 million.

dual identity is a direct result of the changing prognosis for SBIRS, which was restructured in 2005 due to chronic technical problems and cost growth. The restructuring reduced the SBIRS procurement from five to no more than three satellites and hatched AIRSS as the replacement system.

There is no official decision yet to buy a third SBIRS satellite, but senior Air Force brass have given every indication in recent months that it’s a done deal. Some have even suggested that the service might revert to its original plan and buy five dedicated SBIRS spacecraft.

It is little wonder then that the Senate version of the National Defense Authorization Act for Fiscal Year 2008 axed all funding for AIRSS, while the corresponding House bill provides just $30 million. The bills treat the purchase of a third SBIRS satellite as a foregone conclusion; each adds $100 million to the SBIRS budget to be applied toward the purchase of a fourth spacecraft.

Unless these recommendations are overturned in conference or ignored by the House and Senate appropriations committees

which is possible but unlikely

the Air Force will not be able to launch an AIRSS flight demonstration around 2010 as planned. As of March, the service was hoping to award a contract for the satellite around August, or near the end of the current fiscal year.

The stated purpose of the demonstration is to retire the risks associated with the main AIRSS instrument, a wide-field-of-view infrared sensor able to stare continuously at a broad swath of the Earth’s surface. The SBIRS satellites, by contrast, feature two sensors: one for staring continuously at known missile fields and other suspect sites; and one that scans the broader area one section at a time. In theory, the wide-field staring sensor would provide faster warning of missile launches than the scanning sensor.

Testing promising missile warning technologies is a worthy endeavor

. But the AIRSS demonstration, which would be an expensive undertaking, is not well synchronized with the operational system that would follow. If AIRSS must be rushed into orbit, the system-development contract would have to be awarded before the demonstration yields any useful data. If, on the other hand, growing confidence in SBIRS takes the pressure off the AIRSS schedule, 2010 could be too early for a demonstration.

This is not to defend SBIRS; if the term snafu didn’t already exist, someone would have had to invent it to describe that program. Nor is this to accept at face value Air Force assertions that SBIRS has turned the corner. Past declarations of impending victory on SBIRS have proven premature, and the U.S. Government Accountability Office warned recently that the effort could have more unpleasant surprises in store.

But the replacement program presented to Congress by the Air Force has no clear schedule, poorly defined requirements and an expensive demonstration whose value in terms of reducing the risk of the operational system is questionable. It is almost as if AIRSS has been set up for Congress to knock down.

That’s unfortunate. SBIRS already is facing obsolescence issues. AIRSS, meanwhile, by leveraging advances in focal-plane and data-processing technology made in the decade since SBIRS was put under contract, has the potential to yield a more capable and less expensive missile warning system.

For these reasons, Congress should provide enough funding next year for the Air Force to continue studying AIRSS and craft a missile-warning roadmap that identifies where it makes sense to infuse new technology into the architecture. At the same time, the Air Force and Congress can continue to assess progress – or the lack thereof – on SBIRS and evaluate the impact of the obsolescence issue.

By this time next year, if not sooner, the Air Force should have a much better sense of where it needs to go with its missile warning program. If disaster strikes once again on SBIRS in the meantime, money from that budget could be reprogrammed to put a fast-track, low-risk AIRSS program into high gear.