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Friday, November 8, 2019

F-117 Nighthawk Stealth Fighter Profile

F-117 Nighthawk Stealth Fighter Profile The Lockheed F-117A Nighthawk was the worlds first operational stealth aircraft. Designed to evade enemy radar systems, the F-117A was developed as a stealth attack aircraft by Lockheeds famed Skunk Works unit in the late 1970s and early 1980s. Though in use in by 1983, the existence of the F-117A was not acknowledged until 1988 and the aircraft was not fully revealed to the public until 1990. Though used in 1989 over Panama, the F-117As first major conflict was Operation Desert Shield/Storm in 1990-1991. The aircraft remained in service until being formally retired in 2008. Stealth During the Vietnam War radar-guided, surface-to-air missiles began to take an increasingly heavy toll on American aircraft. As a result of these losses, American planners began seeking a way to make an aircraft invisible to radar. The theory behind their efforts was initially developed by Russian mathematician Pyotr Ya. Ufimtsev in 1964. Theorizing that the radar return of a given object was not related to its size but rather its edge configuration, he believed that he could calculate the radar cross-section across a wings surface and along its edge. Utilizing this knowledge, Ufimtsev conjectured that even a large aircraft could be made stealthy. Unfortunately, any aircraft taking advantage of his theories would be inherently unstable. As the technology of the day was incapable of producing the flight computers necessary to compensate for this instability, his concepts were shelved. Several years later, an analyst at Lockheed came across a paper about Ufimtsevs theories and, as technology had sufficiently advanced, the company began developing a stealth aircraft based on the Russians work. Development Development of the F-117 began as a top secret black project at Lockheeds famed Advanced Development Projects unit, better known as the Skunk Works. First developing a model of the new aircraft in 1975 dubbed the Hopeless Diamond due to its odd shape, Lockheed built two test aircraft under the Have Blue contract to test the designs radar-defying properties. Smaller than the F-117, the Have Blue planes flew night test missions over the Nevada desert between 1977 and 1979. Utilizing the F-16s single-axis fly-by-wire system, the Have Blue planes solved the instability issues and were invisible to radar. Lockheed Have Blue test aircraft. US Air Force Pleased with the programs results, the US Air Force issued a contract to Lockheed on November 1, 1978, for the design and production of a full-sized, stealth aircraft. Led by Skunk Works chief Ben Rich, with assistance from Bill Schroeder and Denys Overholser, the design team used specially designed software to create an aircraft which used facets (flat panels) to scatter over 99% of radar signals. The final result was an odd-looking aircraft that featured quadruple-redundant fly-by-wire flight controls, an advanced inertial guidance system, and sophisticated GPS navigation. To minimize the aircrafts radar signature, designers were forced to exclude onboard radar as well as minimize the engine inlets, outlets, and thrust. The result was a subsonic attack bomber capable of carrying 5,000 lbs. of ordnance in an internal bay. Created under the Senior Trend Program, the new F-117 first flew on June 18, 1981, only a mere thirty-one months after moving into full-scale development. Designated the F-117A Nighthawk, the first production aircraft was delivered the following year with operational capability reached in October 1983. All told 59 aircraft were built and delivered by 1990. F-117A Nighthawk GeneralLength: 69 ft. 9 in.Wingspan: 43 ft. 4 in.Height: 12 ft. 9.5 in.Wing Area: 780 sq. ft.Empty Weight: 29,500 lbs.Loaded Weight: 52,500 lbs.Crew: 1PerformancePower Plant: 2 Ãâ€" General Electric F404-F1D2 turbofansRange: 930 milesMax Speed: Mach 0.92Ceiling: 69,000 ft.Armament2 Ãâ€" internal weapons bays with one hard point each (total of two weapons) Operational History Due to the extreme secrecy of the F-117 program, the aircraft was first based at isolated Tonopah Test Range Airport in Nevada as part of the 4450th Tactical Group. To aid in protecting the secret, official records at the time listed the 4450th as being based at Nellis Air Force Base and flying A-7 Corsair IIs. It was not until 1988 that the Air Force acknowledged the existence of the stealth fighter and released a fuzzy photograph of the aircraft. Two years later, in April 1990, it was publicly revealed when two F-117As arrived at Nellis during daylight hours. F-117A Nighthawk. US Air Force Gulf War With the crisis in Kuwait developing that August, the F-117A, now assigned to the 37th Tactical Fighter Wing, deployed to the Middle East. Operation Desert Shield/Storm was the aircrafts first large-scale combat debut, though two had been secretly used as part of the invasion of Panama in 1989. A key component of the coalition air strategy, the F-117A flew 1,300 sorties during the Gulf War and struck 1,600 targets. The forty-two F-117As of the 37th TFW succeeded in scoring an 80% hit rate and were among the few aircraft cleared to strike targets in downtown Baghdad. Kosovo Returning from the Gulf, the F-117A fleet was shifted to Holloman Air Force Base in New Mexico in 1992 and became part of the 49th Fighter Wing. In 1999, the F-117A was used in the Kosovo War as part of Operation Allied Force. During the conflict, an F-117A flown by Lieutenant Colonel Dale Zelko was downed by a specially modified SA-3 Goa surface-to-air missile. Serbian forces were able to briefly detect the aircraft by operating their radar on unusually long wavelengths. Though Zelko was rescued, the remains of the aircraft were captured and some of the technology compromised. In the years after the September 11 attacks, the F-117A flew combat missions in support of both Operations Enduring Freedom and Iraqi Freedom. In the latter case, it dropped the opening bombs of the war when F-117s struck a leadership target in the conflicts opening hours in March 2003. Though a highly successful aircraft, the F-117As technology was becoming outmoded by 2005 and maintenance costs were rising. F-117A Nighthawk on display at the National Museum of the US Air Force. US Air Force Retirement With the introduction of the F-22 Raptor and development of the F-35 Lightning II, Program Budget Decision 720 (issued December 28, 2005) proposed retiring the F-117A fleet by October 2008. Though the US Air Force had intended to keep the aircraft in service until 2011, it decided to begin retiring it to enable the purchase of additional F-22s. Due to the sensitive nature of the F-117A, it was decided to retire the aircraft to its original base at Tonopah where they would be partially disassembled and placed in storage. While the first F-117As left the fleet in March 2007, the final aircraft departed active service on April 22, 2008. That same day official retirement ceremonies were held. Four F-117As remained in brief service with the 410th Flight Test Squadron at Palmdale, CA and were taken to Tonopah in August 2008.

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