TYPE: Precision attack fighter with stealth elements, optimised for radar energy dispersion and low IR emission.

PROGRAMME: Development began with USAF Flight Dynamics Laboratory contract to Lockheed Advanced Development Projects (Skunk Works), funded by DARPA under Have Blue programme; two XST (Experimental Stealth Technology) prototypes produced, each powered by two 11.12-12.46 kN (2,500-2,800 lb st) GE CJ610s; first flight at Groom Lake, Nevada, December 1977 by William C. Park; first prototype crashed 4 May 1978; second XST crashed at Tonopah Test Range 1980; similar to F-117 apart from inward-canted ruddervators. Span 6.71 m (22 ft 0 in); length 11.58 m (38 ft 0 in); max T-O weight 5,443 kg (12,000 lb); leading-edge sweep 72° 30'; four-transparency canopy.
Development and manufacture of operational F-117A started November 1978 under Senior Trend programme. First of five pre-series aircraft (Article numbers 780 to 784) flew 18 June 1981; one crashed 20 April 1982. Planned production of 100 reduced to 59 (Article numbers 785-843) of which 785 crashed on first flight 21 June 1982; first hand-over to USAF (Article 787) 23 August 1982; funding 13 in FY 1980 and 11, 10, 11 and 14 in FYs 1982-85; final assembly at Tonopah; deliveries seven, eight, eight, eight, eight, seven, five, four and three in calendar years 1982-90 (final delivery mid-July); first picture and designation released 10 November 1988; first operational deployment in Operation Just Cause over Panama, 21 December 1989, when two F-117As each dropped a 907 kg (2.000 lb) laser-guided bomb on barracks area at Rio Hato; all 56 in-service F-117AS participated in 1991 Gulf War against Iraq, flying some 1,270 missions. Weapon system improvement began in 1989 and to continue to 2005; improvements installed by 1991 include 'four-dimensional' flight management system (time on waypoint ±1 second) and new cockpit instrumentation with full colour MFDs and digital moving map
First F-117A unit, 4450th Tactical Group at Tonopah (122 nm; 225 km; 140 miles north-west of Las Vegas) Nevada, formed 1980 and equipped with 18 A-7D Corsair IIs until first F-117A arrived; initial operational capability achieved 26 October 1983; unit transferred from direct control of Tactical Air Command to Tactical Fighter Weapons Center at Nellis AFB 1985; first of several public air display appearances made April 1990; unit renamed 37th Tactical Fighter Wing of 12th Air Force October 1989; strength now 40 F-117As divided between 415th and 416th TFS; A-7Ds replaced in training and chase duty by eight T/AT-38 Talons of 417th TFTS, also with balance of 16 remaining F-117As; wing expected to move to Holloman AFB, New Mexico, 1992.

VARIANTS: None known, but Lockheed proposal submitted to USAF after 1991 Gulf War for potential upgrade (capable of retrofit) which could include bubble canopy, redesigned engine inlets, improved exhaust system, and a radar with 'smart skin' conformal antennae.

CUSTOMERS: USAF.

COSTS: $6,560 million programme (1990), including $2,000 million R&D, $4,270 million for procurement and $295,4 million for infrastructure. Average unit cost $42.6 million (then-year dollars).

DESIGN FEATURES: Multi-faceted airframe designed to reflect radar energy away from originating transmitter, particularly downward-looking AEW aircraft; vortexes from many sharp edges, including leading-edge of wing, designed to form co-ordinated lifting airflow pattern; wings have 67° 30' sweepback, much greater than needed for subsonic performance, with aerofoil formed by two flat planes underneath and three on upper surface; forward underwing surface blends with forward fuselage; all doors and access panels have serrated edges to suppress radar reflection; internal weapon bay 4.7 m (15 ft 5 in) long and 1.75 m (5 ft 9 in) wide divided longitudinally by two lengthwise doors hinged on centreline; boom refuelling receptacle on port side of top plate, aft of cockpit. Frontal radar cross section estimated as 0.01 m² (0.1 sq ft).

FLYING CONTROLS: Four omnidirectional air probes at nose indicate GEC Astronics quadruplex fly-by-wire control system, similar to that of F-16, using two-section elevons and all-moving ruddervators together for control and stability; ruddervators swept about 65° and set at 85° to each other.

STRUCTURE: Material principally aluminium; two-spar wings; fuselage has flat facets mounted on skeletal subframe, jointed without contour blending; surfaces coated with various radar-absorbent materials. Ruddervators being replaced by new units of thermoplastic graphite composites construction, removing previous speed restriction due to flutter.

LANDING GEAR: Tricycle type by Menasco, with single wheels all retracting forward. Loral brakes and wheels; Goodyear tyres. All doors have serrated edges to suppress radar reflections. Emergency arrester hook with explosively jettisoned cover.

POWER PLANT: Two 48.0 kN (10,800 lb st) class General Electric F404-GE-F1D2 non-augmented turbofans. Rectangular overwing air intakes with 2.5 x 1.5 cm (1 x 5/8 in) heated grid for anti-icing and low observability. Auxiliary air intake doors in horizontal surface immediately to the rear. Part of cold air ingested bypasses engine and is mixed with exhaust gases for cooling. Narrow-slot 'platypus' exhausts in rear fuselage, 1.65 m (5 ft 5 in) long and 0.10 m (4 in) high, with extended lower lip, surrounded by heat tiles of type used on Space Shuttle and with 11 vertical, internal guide vanes. Sunstrand air turbine starter. In-flight refuelling receptacle in decking aft of cockpit, illuminated for night refuelling by lamp at apex of cockpit. Optional drop tank on internal weapon pylon.

ACCOMMODATION: Pilot only; McDonnell Douglas ACES II zero/zero ejection seat. Five individually framed flat-plate windows, including single-piece windscreen. Transparencies, gold-coated for radar dissipation, produced by Serracin/Sylmar Corporation. Canopy hinged to open upward and backward.

SYSTEMS: Allied Signal environmental control, auxiliary power and emergency power systems.

AVIONICS: Forward-looking infra-red (FLIR) sensor, with dual fields of view, in recessed emplacement, covered by fine mesh screen, below windscreen. Retractable downward-looking DLIR and laser designator beneath forward fuselage to starboard of nosewheel bay. HUD based on Kaiser AN/AVQ-28; large head-down display for FLIR imagery flanked by two multi-function CRTs. Retractable radio antennae beneath fuselage, ahead of port main landing gear, and on spine. Honeywell radar altimeter, INS, air data computer and multi-purpose display system; IBM mission computer; GEC Astronics flight control computer/navigation interface and autopilot computer (NIAC) system; SLI Avionic Systems Corp expanded data transfer system and AHRS. Digital moving map added as retrofit. Navstar GPS.

ARMAMENT: "Full range of USAF tactical fighter ordnance", principally two 907 kg (2,000 lb) bombs: BLU-109B low-level laser-guided or GBU-10/GBU-27 laser-guided glide weapons; alternatively, AGM-65 Maverick or AGM-88 HARM ASMs. Internal carriage on two extensible beams in weapon bay. (Only missiles with seeker heads extended below aircraft prior to launch; bombs released from within weapon bay.)