The Airborne Laser's turret ball assembly under construction.(Photograph courtesy of Boeing)
From Popular Mechanics:
Ballistic missile defense via airplanes mounted with lasers may seem straight out of science fiction, but add a fleet of UAVs with mirrors to increase the laser's range, and military insiders say the system might just work.
In the history of comic books, rarely has a mastermind come up with a weapon quite as unabashedly cool as the Airborne Laser. Take a relatively standard Boeing 747 aircraft, and load it with a massive chemical laser. And not just any laser, but a megawatt-class beam weapon with an impressive name: COIL, short for Chemical Oxygen Iodine Laser. Thanks to a deformable mirror that changes shape using hundreds of twitching actuators, the Airborne Laser (ABL) can account for the atmospheric turbulence that would normally distort and smother a beam traveling at long distances. Throw in a fire-control system that can hit a fast-moving target from hundreds of miles away, and an infrared beam that's invisible to the naked eye, and ABL seems like the sci-fi definition of death from above. It even looks cool, with a turret jutting out of the nose of the plane.
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