The ABL weapon system consists of a high-energy, chemical oxygen iodine laser (COIL) mounted on a modified 747-400F (freighter) aircraft to shoot down theater ballistic missiles in their boost phase.
All of the COIL laser modules and 77 tonnes of flight hardware have been installed into the test plane - an old 747-200 fuselage that was rescued from an aircraft junkyard - at the 18 000 ft2 System Integration Laboratory (SIL) at Edwards Air Force Base in California. All of the ground-based laser tests will take place at the specially designed $35 m facilities. After tests inside the SIL are complete, the COIL will be dismantled and reassembled inside the ABL.
Next to the SIL is the ground pressure recovery assembly (GPRA) - a giant airtight sphere that simulates the reduced air pressure at 38 000 ft for tests that will mimic the plane's real-life operating conditions.