The AIM-9 Sidewinder is a heat-seeking, short-range, air-to-air missile carried by fighter aircraft and recently, certain gunship helicopters. Variants and upgrades remain in active service with many air forces after five decades. When a Sidewinder missile is being launched, NATO pilots use the brevity code Fox Two in radio communication, as with all “heat-seeking“ missiles.
About 110,000 Sidewinders have been built, of which perhaps one percent have been used in combat, resulting in some 250-300 kills world-wide to date. The missile was designed to be simple to upgrade.