The Airborne Laser (ABL) still has a number of major unresolved issues that Congress must consider, a recent Congressional Research Service (CRS) report says.

Technical, funding, treaty and basing issues still surround ABL, according to the July 9 report. Also, MDA is exploring alternatives to ABL for the Boost Phase Intercept (BPI) mission.

"Recent changes in funding profiles for both the ABL and for the MDA's new kinetic kill vehicle reinforce the uncertainty related to the ABL program," the report says. "Specific issues that may confront Congress include the severity and implications of the ABL programmatic and technological challenges, how the ABL might be employed if and when it is fielded, the potential for industrial base problems, the scheduled lethality test, and consideration of boost-phase alternatives to the ABL."

In January 2002, the Missile Defense Agency (MDA) dropped the traditional requirements-setting process in favor of a "capabilities-based" approach, intended to more quickly field a system capable of responding to some, if not all, of the current ballistic missile threats, according to the report.

The ABL program's new requirements setting process, and its focus on developing a less sophisticated system based on currently available technology, may result in less risk of cost and schedule growth in the future, the report says.

Also, the total ABL program cost cannot be given or estimated because of the acquisition strategy adopted by MDA for missile defense, CRS says. Nor has the final system architecture been identified, meaning that the total number of ABL aircraft to be procured has not been determined. The most recent cost estimate, from the Clinton administration, was $10.7 billion (lifecycle costs) for the same number of aircraft. No other system cost data are available.

A number of questions are likely to be asked regarding the size of the ABL inventory, according to CRS. ABL will be a highly visible asset. It is very large, and will be escorted by fighter aircraft. Its high altitude will also help to distinguish it from other wide-body aircraft.

Long in-theater on-station time for the ABL is premised on forward basing. These forward bases would likely not have chemical replenishment capabilities, meaning return flights to the United States if the laser is used. An enemy could wait until an orbiting ABL is being refueled or is absent before initiating a missile attack. A force of seven aircraft might only be expected to provide 24-hour theater ballistic missile (TBM) BPI coverage of one theater, the report said.

DOD's decision in Spring 2006 to postpone the purchase of five ABL aircraft raises the issue of exactly what a small number of ABL aircraft - in this case two - could achieve operationally, according to CRS.

ABL is facing possible budget cuts of $200 million - $250 million from its roughly $550 million fiscal 2008 budget request, which likely would delay its long-awaited 2009 lethal demonstration.