The ABL is a Boeing 747 aircraft being equipped with a high-powered chemical laser to destroy ballistic missiles in their boost phase. Boeing Co. of Chicago is the prime contactor on the effort.

As envisioned, the aircraft would fly in a figure-eight pattern over an area deemed a likely site of a missile launch. Onboard infrared sensors would detect the launch and feed that information into a computer that would direct the laser turret to point at the ascending missile. The turret would then fire two lower-powered solid-state lasers—one to track the missile and one to measure atmospheric distortion—before shooting the high-powered chemical laser at the target.