Lockheed F-117 Nighthawk

The Lockheed F-117 Nighthawk is a retired American single-seat, subsonic, twin-engined stealth attack aircraft developed by Lockheed's Skunk Works division and operated by the United States Air Force (USAF). It was the first operational aircraft to be designed with stealth technology. Work on what would become the F-117 began in the 1970s to counter increasingly sophisticated Soviet surface-to-air missiles (SAMs). In 1976, the Defense Advanced Research Projects Agency (DARPA) issued Lockheed a contract to produce the Have Blue technology demonstrator, whose test data validated the concept. On 1 November 1978, Lockheed decided to develop the F-117. Five prototypes were produced, the first of which performed its maiden flight in 1981 at Groom Lake, Nevada. The first production F-117 was delivered in 1982, and initial operating capability was achieved in October 1983. All aircraft were initially based at Tonopah Test Range Airport, Nevada. The aircraft's faceted shape (made from flat surfaces) heavily contributes to its relatively low radar cross-section of about 0.001 m2 (0.0108 sq ft). To minimize its infrared signature, its non-circular tail pipe mixes hot exhaust with cool ambient air and lacks afterburners; it is also restricted to subsonic speeds, as breaking the sound barrier would produce an obvious sonic boom that would increase its acoustic and infrared footprints. While commonly referred to as the "Stealth Fighter", the aircraft was designed and employed as a dedicated attack aircraft; its performance in air combat maneuvering was less than that of most contemporary fighters. The F-117 has integrated digital navigation and attack systems, with targeting via a thermal imaging infrared system and a laser rangefinder/laser designator. It is aerodynamically unstable in all three aircraft principal axes, thus requiring constant flight corrections via a fly-by-wire flight system to maintain controlled flight. Even in the years after it entered service, the F-117 was...