The Lockheed F-117 Nighthawk is a single-engined twin-engined attack aircraft engine developed by the Lockheed Skunk Works secret division and operated by the United States Air Force (USAF). The F-117 is based on technology demonstrators Have Blue .
Nighthawk is the first operational aircraft designed with stealth technology. The first flight occurred in 1981, and the plane reached its initial operating capability status in 1983. The Nighthawk was shrouded in secrets until it was disclosed to the public in 1988. Of the 64 F-117s built, 59 is a production version, with the other five being protesters/prototypes.
The F-117 was widely published for his role in the 1991 Persian Gulf War. Although it was often referred to as the "Stealth Fighter", it was really an attack aircraft. F-117 took part in the conflict in Yugoslavia, where one was shot down by a surface-to-air missile (SAM) in 1999; it is the only Nighthawk lost in battle. The US Air Force stopped F-117 in 2008, mainly because of the F-22 Raptor.
Video Lockheed F-117 Nighthawk
Development
Latar Belakang dan Miliki Biru
In 1964, Pyotr Ufimtsev, a Soviet mathematician, published a seminal paper entitled Wave End Methods in Diffraction Physical Theory in the journal Moscow Institute for Radio Engineering, where he showed that radar power returned from objects related to edge configuration, not size. Ufimtsev is expanding the theoretical work published by the German physicist Arnold Sommerfeld. Ufimtsev shows that he can calculate radar cross sections on the surface of the wings and along the edges. The obvious and logical conclusion is that even large planes can reduce the signs of their radars by exploiting this principle. However, the resulting design will make aerodynamic aircraft unstable, and the state of computer technology in the early 1960s could not provide the type of flight computer that would later allow aircraft like the F-117 and B-2 Spirit to remain in the air. In the 1970s, when Lockheed analyst Denys Overholser discovered Ufimtsev's papers, computers, and software had grown significantly, and the stage was set for the development of a furtive plane.
The F-117 was born after combat experience in the Vietnam War when an increasingly sophisticated Soviet surface-to-air missile (SAMs) dropped heavy bomber aircraft. It was a black project, an ultra-secret program for most of its life: very few people at the Pentagon knew this program even existed, until the F-117 was revealed to the public in 1988. The project started in 1975 with a model called "Hopeless Diamond" (word play on Diamond Hope because of its appearance). The following year, the Agency for Advanced Defense Research Project (DARPA) issued Lockheed Skunk Works a contract to build and test two Stealth Strike Fighters, codenamed " Have Blue ". These subscales combine Northrop T-38A jet engines, fly-by-wire systems from F-16s, landing gears from A-10, and environmental systems from the C-130. By bringing together existing technologies and components, Lockheed built two under-budget demonstrators, totaling $ 35 million for both aircraft, and in no time.
Initial flight of the demonstrators occurred on December 1, 1977. Although both aircraft were lost during the demonstration program, test data proved positive. The success of Have Blue leads the government to increase funding for stealth technology. Much of the increase was allocated to the production of operational stealth aircraft, Lockheed F-117A, under the code name of the " Senior Trend program."
Senior Trends
The decision to produce the F-117A was made on November 1, 1978, and the contract was awarded to Lockheed Advanced Development Projects, known as Skunk Works, in Burbank, California. The program is led by Ben Rich, with Alan Brown as project manager. Rich asks Bill Schroeder, a Lockheed mathematician, and Denys Overholser, a computer scientist, to exploit the work of Ufimtsev. The three designed a computer program called "Echo", which allows for the design of aircraft with flat panels, called facets, arranged in such a way as to deploy more than 99% of the "aircraft" radar signaling energy.
The first YF-117A, serial number 79-0780 , made its maiden flight from Groom Lake, Nevada, on June 18, 1981, just 31 months after the full-scale development decision. The first F-117A production was delivered in 1982, and operational capability was achieved in October 1983. The 4450th Tactical Group stationed at Nellis AFB, Nevada was tasked with the initial F-117 operational development, and between 1981 (before the arrival of the first model) and in 1989 they used LTV A-7 Corsair II for training, to bring all pilots to a general flight training baseline and then as a chase aircraft for the F-117A test.
The Air Force denied the existence of the aircraft until November 10, 1988, when Assistant Secretary of Defense J. Daniel Howard displayed a rough photograph at the Pentagon press conference, disproving many inaccurate rumors about the "F-19" secret form. After the announcement the pilot was able to fly the F-117 during the day and no longer needed to be associated with the A-7, supersonic supersonic T-38 flying for travel and training instead. In April 1990, two F-117 planes were flown to Nellis Air Force Base, Nevada, arrived at noon and displayed publicly to a crowd of tens of thousands.
Five Full Scale Development planes (FSD) were built, designated "YF-117A". The last of the 59 F-117 production was delivered on 3 July 1990.
As stated by the Air Force, "The simplified management of Aeronautical Systems Center, Wright-Patterson AFB, Ohio, combines breakthrough stealth technology with concurrent development and production to pack the aircraft quickly... The F-117A program demonstrates that stealth aircraft can be designed for reliability and maintenance. "
Setting
The operational aircraft is officially designated "F-117A". Most modern US military aircraft use post-1962 marking where the "F" designation is usually an air-to-air fighter, "B" is usually a bomber, "A" is usually a ground attack aircraft, etc. (Examples include F-15, B-2, and A-6.) The F-117 is primarily an attack aircraft, so the designation of "F" is inconsistent with the DoD system. This is an inconsistency that has been repeatedly employed by the US Air Force with several attack aircraft since the late 1950s, including the F-105 Thunderchief Republic and General Dynamics F-111 Aardvark. A televised documentary quotes a senior member of the F-117A development team as saying that the USAF fighter pilot needed to fly a new aircraft is more easily attracted to the plane as "F" for a fighter, as opposed to a bomber ("B" ) or assault ("A") designations.
The designation of "F-117" seems to indicate that it was given an official designation prior to the 1962 US Aircraft Tri-Service Aircraft System and can be considered numerical to be part of the previous "Century series" fighter. The assumption before the disclosure of the aircraft to the public is likely to receive the appointment of the F-19 because the number has not been used. However, no other aircraft received the serial number "100" after the F-111. Soviet warriors acquired by the US in various ways under the Constant Stake program were given the F-series for their evaluation by US pilots, and with the advent of the Young Series fighters, most often referred to as the Century Series.
Like other types of exotic military aircraft flying in the southern Nevada region, such as captured fighters, arbitrary radio calls "117" were commissioned. This same radio call has been used by the enigmatic Puzzle Test and Evaluation Squadron, also known as the "Red Hat" or "Red Eagle," which often flies MiG fighter planes fluttering in the area, but has nothing to do with call it. and the appointment of a formal F-19 which was then considered by the Air Force. Apparently, the use of the "117" radio call became commonplace and when Lockheed released its first flight manual (that is, the Air Force's "dash one" guide), the F-117A was the name printed on its cover.
Maps Lockheed F-117 Nighthawk
Design
When the Air Force first approached Lockheed with the concept of stealth, Director of Skunk Works Kelly Johnson proposed a unanimous design. He believes that the subtle blend forms offer the best combination of speed and stealth. However, his assistant, Ben Rich, points out that the surface of the corners will provide significant reductions in radar signatures, and the necessary aerodynamic control can be provided with a computer unit. The May 1975 Skunk Work Report, "Progress Report No. 2, Stealth High Conceptual Study," shows a unanimous concept, which is rejected for a flat-side approach.
The amazing designs produced surprising and confusing experienced pilots; the Royal Air Force pilot, who flew him as an exchange officer was still a secret project, stating that when he first saw the F-117 photo, he "immediately laughed and thought to [himself] 'it certainly could not fly'". Early stealth aircraft were designed with a focus on minimal radar sections (RCS) rather than aerodynamic performance. Very furtive planes like the F-117 Nighthawk are aerodynamically unstable on the three main axes of the aircraft and require constant flight corrections from the fly-by-wire (FBW) flight system to maintain controlled flight. It was set up to deflect radar signals and the size of an F-15 Eagle.
The single-seat Nighthawk is powered by two General Electric F404 non-afterburning turbofan engines. It is a rechargeable air and a V-tail feature. The maximum speed is 623 miles per hour (1,003 km/h) at high altitude, the maximum climbing rate is 2,820 feet (860 m) per minute, and the service ceiling is 43,000 to 45,000 feet (13,000 to 14,000 m). The cockpit is quite spacious, with ergonomic look and control, but the field of view is somewhat hindered by a large blind spot to the rear.
Avionics
It has fly-by-wire flight controls doubled. To lower development costs, avionics, fly-by-wire systems, and other parts come from General Dynamics F-16 Fighting Falcon, McDonnell Douglas F/A-18 Hornet and McDonnell Douglas F-15E Strike Eagle. The parts were originally described as spare parts on a budget for this aircraft, to keep the F-117 project secret.
The aircraft is equipped with advanced navigation and attack systems integrated into digital avionics. It navigates primarily by GPS and high accuracy inertial navigation. The mission is coordinated by an automated planning system that can automatically perform all aspects of the attack mission, including weapon discharge. The target is acquired by a thermal imaging infrared system, diverted to laser rangefinder/laser pointer that finds the range and sets the target for laser-guided bombs. F-117A internal bay chamber can carry 5,000 pounds (2,300 kg) of weaponry. The typical weapon is a pair of GBU-10, GBU-12 or GBU-27 laser-guided bombs, two BLU-109 penetration bombs, or two Joint Direct Attack Munitions (JDAMs), a GPS/INS guided bomb.
Stealth
F-117 has a Radar cross section of about 0.001 m 2 (0.0108 sqÃ, ft). Among the penalties for stealth is a lower engine impulse due to losses in the inlet and outlet, the very low wing ratio aspect, and the high sweep angle (50 à °) required to bend the radar waves coming sideways. With these design considerations and no afterburner, the F-117 is limited to subsonic speed.
The F-117A does not carry radar, which lowers emissions and cross sections, and whether it carries classified radar detection equipment.
The faceted F-117A (made of 2-dimensional flat surfaces) resulted from the limitations of 1970s computer technology used to calculate radar cross sections. The supercomputer then allows the next plane like a B-2 bomber to use curved surfaces while maintaining stealth, through the use of much more computing resources to perform additional calculations.
An exhaust muffler contributes significant infra-red signals. F-117 reduces IR signatures with non-circular tail pipes (gap shapes) to minimize cross-sectional exhaust volume and maximize hot exhaust mixing with cold ambient air. The F-117 does not have afterburner, because the heat exhaust will increase the infrared sign, and breaking the sound barrier will produce a clear sonic explosion, as well as the heating of the skin surface of the plane which also increases the infrared footprint. As a result, its performance in air combat maneuvers required in aerial combat will never match a dedicated combat aircraft. This is not important in the case of this aircraft because it is designed to be a bomber.
Passive radar (multistatic), bistatic radar and especially multistatic radar systems detect some stealth aircraft better than conventional monostatic radar, because the first generation stealth technology (such as F-117) reflects energy away from the transmitter's line of sight, effectively increasing radar cross section RCS) in the other direction, which monitors the passive radar.
Operational history
During the early years of the program, from 1984 to mid-1992, the F-117A fleet was based at Tonopah Test Range Airport, Nevada, where it served under the 4450th Tactical Group. Because the F-117 was classified during this time, the unit was officially located at Nellis Air Force Base, Nevada, and equipped with A-7 Corsair II aircraft. All military personnel are permanently assigned to Nellis AFB, and most of their personnel and families live in Las Vegas. It requires commercial air and trucks to transport personnel between Las Vegas and Tonopah every week. The 4450 was absorbed by the 37th Tactical Combat Wing in 1989. In 1992, the entire fleet was transferred to Holloman Air Force Base, New Mexico, under the command of the 49th Fighter Wing. The move also eliminates Key Air and American Trans Air flight contracts to Tonopah, which fly 22,000 passenger trips with 300 flights from Nellis to Tonopah per month.
The F-117 reached an initial operating capability status in 1983. Nighthawk pilots called themselves "Bandit". Each of the 558 Air Force pilots who have flown the F-117 has Bandit numbers, such as "Bandit 52", which shows the sequential sequence of their first flight on F-117.
The F-117 has been used several times in the war. His first mission was during the United States invasion of Panama in 1989. During the invasion, two F-117A Nighthawks dropped two bombs at the Rio Hato airfield.
During the 1991 Gulf War, the F-117 flew about 1,300 surprise attacks and scored directly on 1,600 high-value targets in Iraq during 6,905 flight hours. Drip leaflets on Iraqi troops showed a devastating F-117 ground targets and warned "Escape now and save yourself". Initial claims of its effectiveness were discovered and then exaggerated. For example, it is claimed that F-117 represents 2.5% of Coalition tactical planes in Iraq and they attack more than 40% of strategic targets; this ignores the fact that only 229 plane coalitions can drop and point to laser-guided bombs where 36 F-117 represents 15.7%, and only USAF has bomb I-2000 aimed at hardened targets, so F-117 represents 32 % of all coalition aircraft that can send such bombs. Initial reports of F-117s that accounted for 80% of their target were then downgraded to "41-60%". On the first night, they failed to reach 40% of the assigned air defense targets, including the Air Defense Operation Center in Baghdad, and 8 targets are still functioning from 10 that can be assessed. In their Desert Storm white paper, the USAF claims that "the F-117 is the only plane that plans to take risks over downtown Baghdad" and that this area is well defended. In fact, most air defenses are on the outskirts of the city and many other planes reach the target in the city center, with minimal casualties when they strike at night like the F-117. This means they avoid the optical AAA and infra-red SAM which is the biggest threat to the Coalition aircraft.
The aircraft operated secretly from Tonopah for nearly a decade, but after the Gulf War it moved to Holloman in 1992 - but integration with the USAF's "non-stealth" iron jet was slowly taking place. As one of the F-117A's senior pilots then said: Due to continuous confidentiality others continue to see the aircraft as "no business, stand-alone system". F-117A and men and women from the 49th Fighter Wing deployed to Southwest Asia on several occasions. On their first placement, with the help of air refueling, the pilots flew non-stop from Holloman to Kuwait, a flight of about 18.5 hours - a record for the one-seat fighters standing today.
Loss
One F-117 (AF ser. No. 82-0806) disappears from enemy action. It fell during a mission against the Yugoslav Army on 27 March 1999, during Operation of the Allied Forces. At approximately 8:15 pm, the aircraft was acquired by a fire control radar at a distance of 13 km and a height of 8 km: SA-3 was later launched by the Yugoslav version of Soviet Isayev S-125 "Neva" (NATO SA-3 name "Goa" ) anti-aircraft missile system. The launcher was run by the 3rd Battalion of the 250th Military Defense Brigade under the command of Colonel ZoltÃÆ'án Dani. According to Dani in a 2007 interview, his troops saw the plane on the radar when the doors of the bombs opened, raising its radars. One source said one of the missiles was blown up by a short distance near the F-117. Dani said he kept most of his missile sites by frequently removing them, and had complainants looking for F-117 and other NATO planes. He also stated that he oversaw the modification of his targeting radar to improve his detection capabilities.
After the explosion, the plane became uncontrollable, forcing the pilot to pull out. The pilot was discovered six hours later by the United States Air Force Pararescue team. The photographs show that the plane hit the ground at low speed in reverse position, and that the fuselage remains relatively intact. The Serbs invited Russian personnel to inspect the remains of the aircraft, at the expense of the 25-year-old US stealth technology. The F-117 pilot was originally misidentified. Although the name "Capt Ken 'Wiz' Dwelle" was painted on the canopy, it was revealed in 2007 that the pilot was Lieutenant Colonel Dale Zelko. Stealth technology from falling F-117 may have been acquired by Russia and China.
Some American sources state that the second F-117A was damaged during the same campaign, alleged on 30 April 1999; the plane returned to the base, but should never fly again.
Service and retirement later
The use of aircraft as part of Operation Allied Forces continued, and was later used in Operation Enduring Freedom in 2001 and Operation Iraqi Freedom in 2003. The aircraft is operated by the US Air Force.
Losses in Serbia caused the USAF to make verses from their existing weapon schools to improve tactics. More training was done with other units, and the F-117A began participating in the Red Flag exercise. Though already advanced for the time, the fuselage of the F-117 aircraft was in need of massive maintenance and was eventually replaced by streamlined forms produced by computer-aided design. Other weapon systems began to take over the role of F-117, as the F-22 Raptor gained the ability to drop guided bombs. In 2005, aircraft were only used for specific missions, such as if a pilot needed to verify that the right target had been hit, or when minimal collateral damage was essential.
The Air Force once planned to retire F-117 in 2011, but the Decision Budget Program 720 (PBD 720), dated December 28, 2005, proposed retiring in October 2008 to free about $ 1.07 billion to buy more F-22s. PBD 720 requested 10 F-117s to retire on FY2007 and 42 remaining in FY2008, stating that other Air Force aircraft and missiles secretly deliver precision weapons, including B-2 Spirit, F-22 and JASSM. The planned introduction of multirole F-35 Lightning II also contributed to the retirement decision.
In late 2006, the Air Force closed the F-117 formal training unit (FTU), and announced the F-117 retirement. The first six retired aircraft made the final flight on March 12, 2007 after the ceremony at Holloman AFB to commemorate the career plane. Brigadier General David L. Goldfein, commander of 49th Fighter Wing, said at the ceremony, "With the launch of today's big aircraft, the circle is getting closer - their service to our nation's defense is fulfilled, their mission is accomplished and work" We're done. We sent them today to their final resting place - the house they are familiar with - their first home, and the only one, outside Holloman. "
Unlike most other Air Force aircraft who retire to Davis-Monthan AFB to dispose of, or spread to museums, most F-117s are housed in "Type 1000" storage in their original hangars at Tonopah Test Range Airport. In Tonopah, their wings are removed and planes are kept in a climate-controlled original hangar. The deactivation took place in eight phases, with operational aircraft retreating to Tonopah in seven waves which began on March 13, 2007, and ended with the arrival of the last wave on April 22, 2008. Four aircraft flying outside April by the 410th Fly Test Squadron in Palmdale for flight test. In August, the remaining two. The last F-117 (AF Serial No. 86-0831) left Palmdale to fly to Tonopah on August 11, 2008. With the last retired airplane, the 410 was not active during the ceremony on 1 August 2008.
Five planes were placed in the museum, including the first four YF-117As and some of the remaining F-117s shot down over Serbia. Throughout 2009, one F-117 was removed. AF Series F-117 No. 79-0784 was canceled at the Palmdale test facility on April 26, 2008. This was the last F-117 in Palmdale and was canceled to test an effective method for destroying the F-117 airframes. Although officially retired, the F-117 fleet remained intact, and photographs showed the plane carefully calibrated. The F-117 has been seen flying in the recent Nellis Bombing Range in July 2015. Some aircraft are flown regularly.
Congress has declared that all F-117s mothballed from 30 September 2006 onwards to be maintained "under conditions that would allow the withdrawal of the aircraft for future services" as part of the National Defense Authorization Act of 2007. In April 2016, MPs appeared ready to "remove the requirement that certain F-117 aircraft be maintained under conditions that would allow the withdrawal of planes for future services," which would move them from storage to aerospace maintenance and regeneration pages in Arizona. to scavenge for parts that are hard to find, or completely unloaded.
On September 11, 2017, it was reported that in accordance with the National Defense Authorization Act for Fiscal Year 2017, signed into law on December 23, 2016, "the Air Force will remove four F-117s annually to completely release them - a process known as plane demilitarization... "
Variant
F-117N "Seahawk"
The United States Navy tested the F-117 in 1984 but determined that it was not suitable for carrier use. In the early 1990s, Lockheed proposed an upgraded, carrier-capable variant of the F-117 dubbed "Seahawk" to the Navy as an alternative to the canceled A/F-X program. The unsolicited proposal was poorly received by the Department of Defense, who had little interest in the sole mission capability of the aircraft, primarily because it would take money from the Joint Advanced Strike Technology program, which evolved into a Joint Strike Fighter. The new aircraft will be different from the ground-based F-117 in several ways, including the addition of "elevator, bubble canopy, less sharp wings and reconfigured tails". The "N" variant will also be reengineered to use the General Electric F414 turbofan instead of the older General Electric F404. The aircraft will be optionally equipped with hooks, allowing for an additional 8,000 pounds (3,600 kg) of cargo, and a new ground-to-air radar attack with air-to-air capability. In that role, the F-117N can carry air-to-air AIM-120 AMRAAM missiles.
After being rejected by the Navy, Lockheed submitted a recent proposal that included afterburning and greater emphasis on the F-117N as a multi-mission aircraft, not just the attack aircraft. To increase interest, Lockheed also proposed a ground-based variant of F-117B that shares most of the F-117N's capabilities. This variant is proposed to the USAF and Royal Air Force. Some RAF exchange officers flew the F-117 during service, two RAF pilots officially evaluating the aircraft in 1986 as a reward for UK aid with the American bombing in Libya that year, and Britain refused an offer during the Reagan administration to buy aircraft. This updated F-117N proposal is also known as A/F-117X . Both F-117N and F-117B are ordered.
Operator
- AS
The aircraft's official name is "Night Hawk", but an alternative form of "Nighthawk" is often used.
Because it prioritizes stealth through aerodynamics, it gets the nickname "Wobblin 'Goblin" because of its alleged instability at low speed. However, the F-117 pilot has declared his nickname unfeasible. "Wobblin '(or Wobbly) Goblin" is likely to be a relic from the beginning of having a Blue Day Future Trend (FSD) day of the project when instability is a problem. At USAF, "Goblin" (without wobbly) continues as a nickname because of the airplane's appearance. During Operation Desert Storm, the Saudis call the plane "Shaba", the Arabic for "Ghost".
Specifications
Data from National Museum of USAF, AS. Air Force
General characteristics
- Crew: 1
- Length: 65 ft 11 in (20.09 m)
- Wide width: 43 ft 4 inches (13.21 m)
- Height: 12 ft 9.5 in (3.90 m)
- Wings area: 780 ftÃ,ò (72,5 mÃ,ò)
- Empty weight: 29,500 lb (13,380 kg)
- Weight being loaded: 52,500 lb (23,800 kg)
- Powerplant: 2 ÃÆ'â ⬠"General Electric F404-F1D2 turbofan, 10,600 lbf (48.0 kN) respectively
Performance
- Maximum speed: Mach 0.92 (617 mph, 993 km/h)
- Roaming speed: Mach 0.92
- Range: 930 nmi (1720 km)
- Service ceiling: 45,000 feet (13,716m)
- Wings loading: 67.3 lb/ftÃ,ò (329 kg/mÃ,ò)
- Push/weight: 0.40
Armament
- 2 ÃÆ'â ⬠"internal weapons are divided by one hardpoint each (a total of two weapons) equipped to carry:
- Bomb:
- GBU-10 Paveway II is guided by bomb laser with 2,000 lb Mk84 blast/fragmentation or BLU-109 or BLU-116 Penetrator warhead
- GBU-12 Paveway II guided by bomb laser with explosive/fragmentation 500 lb Mk82
- GBU-27 Paveway III laser guided with 2,000 lb Mk84 blast-fragmentation or BLU-109 or BLU-116 Penetrator warhead
- GBU-31 JDAM INS/GPS is guided by 2,000 lb Mk84 blast-frag or BLU-109 Penetrator warhead
- nuclear bomb B61
- Bomb:
Important appearances in media
The professional football team of Omaha Nighthawks America uses the F-117 Nighthawk as its logo.
See also
- Sea Shadow
- Wainfan Facetmobile
Related development
- Lockheed Got Blue
Airplane with equivalent role, configuration, and era
- BAE Replica
- MBB Lampyridae
Source of the article : Wikipedia