F-117 Nighthawk

From Wikipedia, the free encyclopedia

F-117 Nighthawk
Type	Stealth bomber/attack aircraft[1]
Manufacturer	Lockheed Martin
Maiden flight	1981-06-18
Retired	2008[2]
Status	Active
Primary user	United States Air Force
Number built	59 (55 active)
Unit cost	US$45 million in 1983
Developed from	Lockheed Have Blue

The Lockheed F-117A Nighthawk is the world's first operational aircraft completely designed around stealth technology. Flown solely by the United States Air Force, it is a direct descendant of the Have Blue stealth prototype program.

The F-117A was widely publicized during the Gulf War. The Air Force has been trying to retire the F-117, due mainly to the deployment of the more effective F-22 Raptor. The Air Force is planning to retire the F-117 from October 2006 to 2008,^[3][4] and no new pilots will be trained to fly the plane.^[5][6][7]

Contents 1 Designation 2 Nicknames 3 Design and operation 4 History 5 Combat 6 Combat losses 7 Retirement 8 Popular culture 9 Specifications 10 References 11 External links 12 Related content

[edit] Designation

The "F-" designation for this aircraft has not been officially explained. However, it seemed to use the pre-1962 USAF fighter sequence like the F-111. Most modern U.S. military aircraft use post-1962 designations in which the designation "F-" is usually an air-to-air fighter, "B-" is usually a bomber, "A-" is usually a ground-attack aircraft, and "C-" is a cargo plane. Examples of this include the F-15 Eagle, the B-2 Spirit, the A-6 Intruder, and the C-130 Hercules). The Stealth Fighter is actually primarily a ground-attack plane so its "F-" designation, as well as its number remain a mystery.

A recent televised documentary quoted a senior member of the F-117A development team as saying that the top-notch fighter pilots required to fly the new aircraft were more easily attracted to an "F-" plane, as opposed to a "B-" or "A-" aircraft.^[8] There has been something of a class distinction between fighter and bomber crews, particularly in the days of the Strategic Air Command (1945-1991), and flying one type often limited a pilot's prospects for flying the other.^{[citation needed]}

The USAF maintains that the F-117A can carry air-to-air missiles, giving it air-to-air combat capability in addition to its primary air-to-ground mission. While that may be technically true, the aircraft is of unknown capability in air-combat. It lacks the radar to guide longer-range missiles and does not carry shorter-range missiles for self-defense. It is likely a poor dogfighter, but there is no expert opinion on its other abilities.^{[citation needed]}

[edit] Nicknames

Before it was given an official name, the engineers and test pilots referred to the ungainly aircraft, which went into hiding during daylight to avoid detection by Soviet satellites, as "Cockroach", a name that is still sometimes used. The aircraft's official nickname is "Night Hawk", but the variant "Nighthawk" is also frequent.^[9] As it prioritised stealth over aerodynamics, the first model was nicknamed "The Hopeless Diamond".^[10] Similarly, it earned the nickname "Wobblin' Goblin" due to its alleged instability at low speeds; according to F-117 pilots, the nickname is undeserved.^[11] Locals in the area around Holloman Air Force Base refer to the aircraft simply as the "Stealth".

[edit] Design and operation

About the size of an F-15C Eagle, the single-seat F-117A is powered by two non-afterburning General Electric F404 turbofan engines, and has quadruple-redundant fly-by-wire flight controls. It is air refuelable. In order to lower development costs, the avionics, fly-by-wire systems, and other parts are derived from the F-16 Fighting Falcon, F/A-18 Hornet and F-15E Strike Eagle. The parts were originally described as spares on budgets for these aircraft, to keep the F-117 project secret.^{[citation needed]}

Among the penalties for stealth are 30% lower engine power, a very low wing aspect ratio, and a high sweep angle (50°) needed to deflect incoming radar waves to the sides.

The F-117A is equipped with sophisticated navigation and attack systems integrated into a digital avionics suite. It carries no radar, which lowers emissions and cross-section. It navigates primarily by GPS and high-accuracy inertial navigation. Missions are coordinated by an automated planning system that can automatically perform all aspects of a strike mission, including weapons release. Targets are acquired by a thermal imaging infrared system, slaved to a laser that finds the range and designates targets for laser-guided bombs.

The F-117A's split internal bay can carry 5,000 lb (2,300 kg) of ordnance. Typical weapons are a pair of GBU-10, GBU-12, or GBU-27 laser-guided bombs, two BLU-109 penetration bombs, two Wind- Corrected Munition Dispensers (WCMD), or two Joint Direct Attack Munitions (JDAMs), a GPS/INS guided stand-off bomb. It can theoretically carry two examples of nearly any weapon in the USAF inventory, including the B61 nuclear bomb. There are a number of bombs that it cannot carry, either because they are too large to fit in its bomb bay, or are incompatible with the F-117's carry system.

[edit] History

In 1964, Pyotr Ya. Ufimtsev, a Russian mathematician, published a seminal paper, "Method of Edge Waves in the Physical Theory of Diffraction," in the Journal of the Moscow Institute for Radio Engineering, in which he showed that the strength of a radar return is proportional to the edge configuration of an object, not its size. Ufimtsev was extending theoretical work published by the German physicist Arnold Sommerfeld.^[12][13][14] Ufimtsev demonstrated that he could calculate the radar cross-section across a wing's surface and along its edge. The obvious conclusion was that even a large airplane could be made stealthy by exploiting this principle. However, the airplane's design would make it aerodynamically unstable, and the state of computer science in the early 1960s could not provide the kinds of flight computers which allow aircraft such as the F-117, F-22 Raptor and B-2 Spirit to stay airborne. However, by the the 1970s, when a Lockheed analyst reviewing foreign literature found Ufimtsev's paper, computers and software had advanced significantly, and the stage was set for the development of a stealthy airplane.^[15]

The decision to produce the F-117A was made in 1973, and a contract awarded to Lockheed Advanced Development Projects, popularly known as the "Skunk Works," in Burbank, California. The program was led by Ben Rich. Rich called on Bill Schroeder, a Lockheed mathematician, and Denys Overholser, a computer scientist, to exploit Ufimtsev's work; they designed a computer program called Echo. Echo made it possible to design an airplane with flat panels, called facets, which were arranged so as to scatter over 99% of a radar's signal energy "painting" the airplane. ^[16][17][18]

The project began with a model called "The Hopeless Diamond" in 1975 due to its bizarre appearance. In 1977, Lockheed produced two 60% scale models under the Have Blue contract. The first flight of the F-117 was in 1977, only 31 months after the full-scale development decision. The first F-117A was delivered in 1982, operational capability was achieved in October 1983, and the last of 59 airplanes was delivered in the summer of 1990.^[19] The Air Force denied the existence of the aircraft until 1988, then in April 1990 an example was put on public display at Nellis Air Force Base, Nevada, attracting tens of thousands of spectators.

During the program's early years, from 1984 to mid-1992, the F-117A fleet was based at Tonopah Test Range, Nevada where it served under the 4450th Tactical Group. The 4450th was absorbed by the 37th Tactical Fighter Wing in 1989. In 1992, the entire fleet was transferred to Holloman Air Force Base, New Mexico, where it was placed under the command of the 49th Fighter Wing. The move eliminated the need for Key Air flights, which flew 22,000 passenger trips on 300 flights from Nellis to Tonopah per month.

As the Air Force has stated,^[1] "Streamlined management by Aeronautical Systems Center, Wright-Patterson AFB, Ohio, combined breakthrough stealth technology with concurrent development and production to rapidly field the aircraft... The F-117A program demonstrates that a stealth aircraft can be designed for reliability and maintainability." The aircraft maintenance statistics are comparable to other tactical fighters of similar complexity. Logistically supported by Sacramento Air Logistics Center, McClellan AFB, California, the F-117A is kept at the forefront of technology through a planned weapon system improvement program located at USAF Plant 42 at Palmdale, California.

Several of the F-117s were painted in a grey camouflage pattern in an experiment to determine the effectiveness of the F-117's stealth during daylight conditions. Also, 2004 and 2005 saw several mid-life improvement programs being implemented on the F-117, including an avionics upgrade.

[edit] Combat

The F-117 has been used several times in war. Its first mission was during the United States invasion of Panama in 1989. During that invasion two F-117A Nighthawks dropped two bombs on Rio Hato airfield. Later, during the Gulf War, it performed well by dropping smart bombs on Iraqi military targets. It has since been used in the Kosovo War in 1999, the Operation Enduring Freedom and in the 2003 invasion of Iraq.

[edit] Combat losses

One F-117 has been lost in combat, to Serbian forces. On March 27, 1999, during the Kosovo War, the 3rd Battalion of the 250th Missile Brigade under the command of Colonel Zoltán Dani, equipped with the Isayev S-125 'Neva-M' (NATO designation SA-3 'Goa'), downed F-117A serial number 82-806 with a Neva-M missile. According to NATO Commander Wesley Clark and other NATO generals, Serb air defenses found that they could detect F-117s with their radars operating on long wavelengths. This made them visible on radar screens. The pilot survived and was later rescued by NATO forces. However, the wreckage of the F-117 was not promptly bombed, and the Serbs are believed to have invited Russian personnel to inspect the remains, inevitably compromising the US stealth technology.^[20] The United States actually considered bombing the remains of the downed aircraft, to prevent possible Russian acquisition of American technology. The United States decided not to, and the remains can still be seen by civilians today at the Museum of Yugoslav Aviation close to Belgrade Nikola Tesla Airport.

An error of assumption was made by many as to the identity of the pilot. While the name "Capt Ken "Wiz" Dwelle" was painted on the canopy, Dwelle was not the pilot on this mission and the true identity of the pilot was not made public.[1][2][3]

The SAMs were most likely guided manually with the help of thermal imagers and laser rangefinders included in the Pechora-M variant of the SA-3s believed to have been used. Reportedly several SA-3s were launched, one of which detonated in close promixity to the F-117A, forcing the pilot to eject. According to an interview, Zoltán Dani was able to keep most of his missile sites intact and had a number of spotters spread out looking for F-117s and other aircraft. Zoltán and his missile crews guessed the flight paths of earlier F-117As from occasional visual and radar spottings and judging from this information and what target had just been bombed, Zoltán and his missile battery determined the probable flight path of F-117A #82-806. His missile crews and spotters were then able to locate it and fire their missiles. Zoltán also claims to have modified his radars to better detect the F-117A, but he has not disclosed what was changed. Parts of the shot-down aircraft are now presented to the public in the Museum of Yugoslav Aviation in Belgrade.

Some American sources acknowledge that a second F-117A was also damaged during a raid in the same campaign, and although it made it back to its base, it never flew again.^[21][22]

[edit] Retirement

Despite its successes in the Kosovo and Iraq Wars and its high mission-capable rate, the F-117 was nonetheless designed with late 1970s technologies. Its stealth technology, while still more advanced than that of any other aircraft but the B-2 Spirit and F-22A, is maintenance heavy. Furthermore, the facet-based stealth design (which has aerodynamic cost) represents an old counter-radar technique that has since been greatly refined. Consequently there was a preliminary decision in 2006 to retire the fleet by 2008. A draft version of the 2006 Quadrennial Defense Review and the 2007 Defense Budget that were leaked to the press proposed retiring the entire fleet to make room for buying more F-22As.^[5] This plan was removed from both the final 2007 Budget and the final QDR.^[23]

By late 2006, the Air Force had closed the F-117 pilot school, and announced the retirement of the F-117^[24] The first six aircraft to be retired made the last flight on March 12, 2007 after a ceremony at Holloman AFB to commemorate the aircraft's storied career. Brigadier General David Goldfein, commander of the 49th Fighter Wing, said at the ceremony, "With the launch of these great aircraft today, the circle comes to a close - their service to our nation's defense fulfilled, their mission accomplished and a job well done. We send them today to their final resting place - a home they are intimately familiar with - their first, and only, home outside of Holloman."^[25]

Unlike most other Air Force aircraft which are retired to Davis-Monthan AFB, the F-117s are being retired to Tonopah. There, their wings will be removed and the aircraft will be stored in their original hangars.^[25]

[edit] Popular culture

• A Sprint commercial in the 1990s featured a large schematic drawing of the F-117, which was then subsequently identified incorrectly by Candice Bergen, their speaker, as a B-2.
• During the 1999 bombing of Serbia, after an F-117 was shot down by Serbian troops, a Serbian performing group Indexovo radio pozorište composed a satirical song "El kondor pada" about its pilot.
• In the 1980s, the Jane's Information Group misidentified the F-117 as the F-19, and featured fictitious artwork in All the World's Aircraft. Modelmakers Testors and Monogram both released hypothetical "F-19 Stealth" models; neither bore any resemblance to the real F-117.

[edit] Specifications

General characteristics

• Crew: 1
• Length: 69 ft 9 in (20.08 m)
• Wingspan: 43 ft 4 in (13.20 m)
• Height: 12 ft 9.5 in (3.78 m)
• Wing area: 780 ft² (73 m²)
• Empty weight: 29,500 lb (13,380 kg)
• Loaded weight: 52,500 lb (23,800 kg)
• Powerplant: 2× General Electric F404-F1D2 turbofans, 10,600 lbf (48.0 kN) each

Performance

• Maximum speed: Mach .92 (617 mph)
• Cruise speed: Mach .92
• Range: unlimited with air refueling ()
• Service ceiling: 69,000 ft (20,000 m)
• Wing loading: 65 lb/ft² (330 kg/m²)
• Thrust/weight: 0.40

Armament

• 2× internal weapons bays with one hardpoint each (total of 2 weapons) equipped to carry:
  • Bombs:
    • JOPANA multiple selectable intertially aided munition
    • BLU-109 hardened penetrator
    • GBU-10 Paveway II laser-guided bomb
    • GBU-27 laser-guided bomb
    • JDAM inertially aided munition
  • Missiles:
    • AGM-65 Maverick air-to-surface missiles
    • AGM-88 HARM air-to-surface missiles
  • Experimental
    • GeDSP v0.69 (Geosynchronous Deployed Satellite Package)
  • Amenities
    • Coffee maker
      • Added prior to Desert Storm for lengthy missions
      • First utilized during Operation Allied Force, staging out of Spangdahlem AB, Germany

[edit] References

[edit] External links

• AirAttack.com on Stealth
• F-117 Anniversary
• F-117 Crash at Air Show in Baltimore
• Air Force Link - Fact Sheet : F-117A Nighthawk
• The 49th Fighter Wing at Holloman Air Force Base is a dead link; use the Internet Archive link instead
• U.S. Air Force F-117A Nighthawk - Wallpaper
• Centennial of Flight about stealth
• Centennial of Flight about F-117
• CNN - U.S. plane shot down, pilot rescued - March 27, 1999
• CNN - Downed NATO pilot rescued, U.S. officials say - March 27, 1999
• CNN - Stealth Nighthawk downed in Yugoslavia - March 28, 1999
• CNN - NATO stealth missions continue after crash - March 28, 1999
• The Advent, Evolution, and New Horizons of United States Stealth Aircraft
• Discovery Military Channel on Stealth
• UCI Ufimtsev
• "Filling the Stealth Gap," in Air and Space Power Journal Fall 2006
• www.f-117a.com - comprehensive site
• FAS F-117A Nighthawk
• F-117 In Action
• NY Times - U.S. Stealth Fighter Is Downed in Yugoslavia
• http://www.nytimes.com/library/world/europe/032899kosovo-rdpa.1.html
• Interception of F-117 by Austrian Airforce
• Venik's Aviation—A US F-117 Night Hawk stealth bomber shot down over Yugoslavia
• Stealth plane set for mothballing by Air Force
• (German) Austrian article about interception of F-117

[edit] Related content

Related development

• Have Blue
• Sea Shadow

Comparable aircraft

• B-2 Spirit

 

Related lists

• List of active United States military aircraft
• List of fighter aircraft
• List of Lockheed aircraft
• List of military aircraft of the United States

See also

• Facetmobile