The US Air Force has granted approval for construction of the first laser hardware for the $1.1 billion military Airborne Laser system. Boeing, TRW and Lockheed Martin are building the 747-based system, which will use a high-energy chemical oxygen iodine laser (COIL) to shoot down ballistic missiles. The system will include a COIL that is lighter and more compact than an earlier module that TRW demonstrated last August. Development and testing of the laser module are expected to be completed before April 1998.