From experience with two XST technology demonstrators, Lockheed's Skunk Works developed the world's first operational tactical warplane to use low observable, or stealth, technology to reduce vulnerability to radar detection.
Developed in great secrecy, the first of five FSD prototypes flew in 1981, and in 1983 the first USAF unit was declared operational. The F-117A was officially acknowledged by the Pentagon in 1988, and in 1989 the type finally went into action during the US invasion of Panama.
The F-117 made a significant contribution to Operation Desert Storm; 42 aircraft flew from Saudi Arabia on nightly missions against high priority targets in Iraq and occupied Kuwait. The F-117A struck Serbian targets during Operation Allied Force in 1999 and suffered its first operational loss.
In USAF planning the F-117 is used for attacks against highly leveraged targets such as C³l centers, air defense sector centers, key bridges and airfields. The F-117A uses a highly accurate internal navigation system to put it in the right position to begin the attack. A forward-looking infra-red and downward-looking infra-red are used to acquire the target. Precision guided munitions are guided to a direct hit on the target by a laser boresighted with the downward-looking infra-red.
After the Gulf War, the F-117 came out of the USAF's black or beyond top secret programmes and was integrated into the war-fighting capabilities of the Air Combat Command. In 1990 Lockheed began an Offensive Capability Improvement Program for the 57 F-117As remaining out of 59 production and five pre-series aircraft delivered. The object was to increase combat effectiveness by reducing cockpit workload. The upgrade added a new flight management system, new cockpit instrumentation with full color multi-function displays, digital moving map and a new turret-mounted infra-red acquisition and designation systems. The internal navigation system was replaced by a new ring laser gyro system that later integrated GPS.
All aircraft had been upgraded by 1995. F-117s currently equip the 49th Fighter Wing at Holloman air force base, NM. Future upgrades with a new digital databus are being considered to allow the F-117 to carry new weapons such as AGM-145 JDAM and AGM-154 JSOW.