An unmanned and self-guided missile, the CALCM can be used for precision strikes against fixed targets deep behind enemy lines. Boeing began modifying the U.S. Air Force's inventory of ALCMs from nuclear to the non-nuclear Conventional Air Launched Cruise Missile (CALCM) in 1986. The CALCM has since proven itself in combat in Operation Desert Storm and Desert Strike. Similar to the ALCM in appearance and mechanical operation.