View source for Northrop F-20 Tigershark

{{short description|Prototype fighter aircraft developed from F-5}}
{{Redirect |F-20||F20 (disambiguation){{!}}F20}}
{{Use dmy dates|date=October 2019}}
{{good article}}
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{{Infobox aircraft
 |name= F-20 Tigershark
 |image= File:F-20 flying.jpg
 |caption= F-20 prototype ''82-0062''
 |alt=
 |type= [[Fighter aircraft]]
 |national_origin = United States
 |manufacturer= [[Northrop Corporation]]
 |first_flight= 30 August 1982
 |introduction=
 |number_built= 3<ref name=Johnsen_p92-8 />
 |status= Canceled
 |primary_user=
 |more_users=
 |developed_from= [[Northrop F-5]]
 |variants=
}}

The '''Northrop F-20 Tigershark''' (initially '''F-5G''') is a prototype [[light fighter]], designed and built by [[Northrop Corporation|Northrop]]. Its development began in 1975 as a further evolution of Northrop's [[Northrop F-5|F-5E Tiger II]], featuring a new engine that greatly improved overall performance, and a modern avionics suite including a powerful and flexible [[radar]]. Compared with the F-5E, the F-20 was much faster, gained [[beyond-visual-range missile|beyond-visual-range]] air-to-air capability, and had a full suite of air-to-ground modes capable of utilizing most U.S. weapons. With these improved capabilities, the F-20 was claimed to become competitive with contemporary fighter designs such as the [[General Dynamics F-16 Fighting Falcon]], but was said to be much less expensive to purchase and operate.

Much of the F-20's development was carried out under a [[United States Department of Defense|US Department of Defense]] (DoD) project called "FX". FX sought to develop fighters that would be capable in combat with the latest [[Soviet Union|Soviet]] aircraft, but excluding sensitive front-line technologies used by the [[United States Air Force]]'s own aircraft. FX was a product of the [[Jimmy Carter|Carter administration]]'s military export policies, which aimed to provide foreign nations with high quality equipment without the risk of US front-line technology falling into Soviet hands. Northrop had high hopes for the F-20 in the international market, but policy changes following [[Ronald Reagan]]'s election meant the F-20 had to compete for sales against aircraft like the F-16, the USAF's latest fighter design. The development program was abandoned in 1986 after three prototypes had been built and a fourth partially completed.<ref name = Johnsen_p92-8>{{harvnb |Johnsen|2006|pp= 92–98}}</ref>

==Development==

===F-5===
When [[John F. Kennedy]] entered office in 1961, the U.S. Department of Defense was instructed to find an inexpensive fighter aircraft that the United States could offer to its allies through the [[Mutual Defense Assistance Act]]. A number of designs were studied, including stripped-down versions of the [[Lockheed F-104 Starfighter]] and [[Vought F-8 Crusader]], and the newly designed Northrop N-156F. On 23 April 1962, the [[United States Air Force]] (USAF) informed the [[United States Secretary of Defense]] that the N-156F had been selected, under the designation F-5 and given the name "Freedom Fighter."<ref name="Donald World Aircraft">Donald 1997, p. 708.</ref> 847 F-5s of various early marks would be produced.<ref>[http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=2282 "Factsheet: Northrop F-5 Freedom Fighter"] {{webarchive|url=https://web.archive.org/web/20121012135126/http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=2282 |date=12 October 2012 }}, National Museum of the United States Air Force. Retrieved: 28 October 2012.</ref>

As the [[Mikoyan-Gurevich MiG-21]] became more common, the USAF initiated the International Fighter Aircraft (IFA) program to provide an equivalent to allies. The USAF desired a lightweight fighter with competitive performance to the MiG, inexpensive when purchased in large numbers, and with reasonable operating costs for prospective customer nations. Although numerous companies entered designs, Northrop's existing F-5 put them in a leading position. They submitted an upgrade, the F-5E Tiger II, with the [[AN/APQ-153]] radar and other changes to allow the [[AIM-9 Sidewinder]] missile to be fired from wing-tip rails. On 20 November 1970, Northrop's entry was announced as the IFA winner.<ref name=Eden>Eden, Paul, ed. "Northrop F-5 family." ''Encyclopedia of Modern Military Aircraft''. London: Amber Books, 2004. {{ISBN|1-904687-84-9}}.</ref> Northrop produced a total of 1,399 F-5E/F Tiger IIs by the time manufacturing ended in 1986.<ref name=Johnsen_p90>{{harvnb|Johnsen|2006|p= 90}}</ref>

===F-5G and export limitations===
In the late 1970s, the Taiwanese [[Republic of China Air Force]] started looking for a fighter aircraft to match improvements made in the Chinese [[People's Liberation Army Air Force]]. In particular, they wanted a platform capable of firing the [[AIM-7 Sparrow]] long-range missile. At the time, the US was in the process of opening up ties with the People's Republic of China after President Nixon's famous [[1972 Nixon visit to China|visit in 1972]]. China considered US support of Taiwan against their interests, and the [[United States Department of State|US State Department]] wanted to tread carefully. They blocked export of all of the AIM-7 capable aircraft, even otherwise outdated early models of the [[McDonnell Douglas F-4 Phantom II]]. The State Department suggested the Israeli [[IAI Kfir]] instead; however, it was rejected.{{Sfn | Inbar | 2008 | p = 33}}  Taiwan was already producing the F-5E under license, so the Department of Defense asked Northrop to study adding an AIM-7 capable radar to the Tiger II as an alternative. This effort became the first of several F-5G studies.<ref>Fink, Donald. "Taiwan Offered F-5G with Sparrow." ''Aviation Week and Space Technology'', 21 August 1978, p. 12.</ref>

In the spring of 1977, [[Jimmy Carter]]'s administration had announced a new military export policy that limited sales of front line designs to [[NATO]], Australia, and Japan.<ref name=saga>Frey, Lieutenant Colonel William. [http://www.airpower.au.af.mil/airchronicles/aureview/1986/may-jun/frey.html "The F-20, Saga of an FX."]  {{Webarchive |url= https://web.archive.org/web/20161231095302/http://www.airpower.au.af.mil/airchronicles/aureview/1986/may-jun/frey.html |date= 31 December 2016 }} ''Air University Review'', May–June 1986.</ref>  Carter stated at the time that the U.S. could not be "both the world's champion of peace and the world's leading supplier of the weapons of war."<ref name= saga /> Previously, there was no coherent export policy, fueling concerns that the US's latest technologies might quickly end up in Soviet hands.<ref name=saga />

Numerous exceptions were made; Israel and Egypt could buy advanced designs under the [[Camp David Agreements]], Israel was even allowed to buy [[McDonnell Douglas F-15 Eagle]]s, a key component in U.S. air-defense technology. Iran was already receiving the [[Grumman F-14 Tomcat]], and this demonstrated the problem with advanced exports in February 1979 when reports emerged that Iran had sold an [[AIM-54 Phoenix]] missile to the Soviets.<ref>"Iran Arms Concern." ''Aviation Week & Space Technology'', 19 February 1979.</ref> South Korea's F-16 order was initially blocked under this policy, but later allowed in the context of strengthening relations.{{Sfn | Thornton | 2004 | p = 252}}  Despite exceptions, the export policy was implemented, covering many potential and current customers. As the F-5G was a relatively modest upgrade to the F-5E, the F-5G appeared to be in a strong position for sales given the limitations placed on rival designs; nonetheless, President Carter personally blocked the sales of the F-5G to Taiwan.<ref name=saga/>{{Sfn | Martin | Schmidt | 1987 | p = 13}}

===FX===
In 1979, problems with the export policy were becoming apparent. The Soviets continued to sell newer aircraft designs to their clients, placing allies of the U.S. at a disadvantage. Denied by the U.S., countries were turning to other vendors for modern fighters, notably France's [[Dassault Mirage 2000]].{{Sfn | Martin | Schmidt | 1987 | p = 2}}  Barry N. Blechman, Assistant Director of the [[Arms Control and Disarmament Agency]], testified that the US reductions in foreign arms transfers had actually encouraged other nations and increased worldwide arms sales.<ref>"Statements by Barry N. Blechman in the U.S. Congress Senate Foreign Relations Committee, Fiscal Year 1980 International Security Assistance Authorization." ''Government Printing Office'' 1979, p. 41.</ref> At the same time, there was considerable pressure to provide a suitable aircraft for Taiwan.{{Sfn | Thornton | 2004 | p = 251}}

The State Department argued that the U.S. needed a modern counterpart for the role the F-5E had occupied in the 1960s and 1970s. In light of Carter's concerns, they suggested that a new aircraft be designed for the role, based on technology that would not pose a threat to the U.S.  After a lengthy study, in January 1980, Carter allowed the development of a new export fighter: the FX.<ref name= saga /> The FX would have to outperform the F-5E; however, it could not use any advanced avionics systems that were also used in U.S. aircraft. Unlike the Mutual Defense Assistance Act programs that led to the F-5E, FX would be entirely privately financed. Moreover, the companies could not market the aircraft directly; all sales would be handled by the Department of Defense.<ref name=saga/>

Both Northrop and [[General Dynamics]] (GD) responded to the FX requirement. GD's F-16/79 was a variant of the F-16A, replacing the [[Pratt & Whitney F100]] turbofan engine with the J79 turbojet and equipping it with downgraded avionics;{{Sfn  | Thornton | 2004 | p = 252}}  Northrop responded with the F-5G.{{Sfn | Martin | Schmidt | 1987 | p = 14}}

===F-20===
When [[Ronald Reagan]]'s administration entered office in 1981, the export restrictions put in place by the Carter administration were slowly relaxed.{{Sfn | Martin | Schmidt | 1987 | p = 14}}  At first, the FX program continued as normal, but a number of events eroded the value of the program and limited the F-5G's potential sales. The signing of the 1982 [[Three Communiques |US-PRC Joint Communiqué]] was a major agreement on arms sales, which continued blocking sales of the F-5G to Taiwan.  By this point the Taiwanese had started their own light fighter project, the [[AIDC F-CK-1 Ching-kuo]]. In signing the Communiqué, the U.S. was signaling that Taiwan would not receive modern aircraft; accordingly, the Ching-kuo became Taiwan's primary focus. As a result, the F-5G's sales potential remained unestablished.<ref>Schemmer, Benjamin. "Pressures Build for DOD to Buy and Help Sell Northrop F-5G as Its Business Prospects Look Bleaker Than Advertised." ''Armed Forces Journal International'', September 1982, pp. 98–104.</ref>

In the summer of 1982, Deputy Secretary of Defense [[Frank Carlucci]] sent a memorandum to the USAF, encouraging it to seek out potential foreign customers to procure FX aircraft.<ref>Starsiak, M.H. "Implications of Moving Away from Formal Foreign Military Sales (FMS): Procedures for Aircraft Sales." ASD-XOR Project, ''U.S. Department of the Air Force'', 1982, pp. 22–23.</ref> However, four months later Carlucci sent a classified memo to the same services to abandon the FX, and green-lighting the exporting of front-line fighters overseas.<ref>Barnard, Richard. "Carlucci Reverses FX Policy for Persian Gulf." ''Defense Week'', 22 November 1982, p. 1.</ref> In December, after prompting from the White House, Carlucci reversed his position again, and directed the USAF to fund a small number of F-20s in the fiscal year 1984 budget.<ref>Barnard, Richard. "Carlucci to AF: 'Buy the F-20'." ''Defense Week'', 20 December 1982, p. 1.</ref>

The future of the FX program seemed doubtful. Following an agreement to sell F-16s to Pakistan,<ref name = "singh">Singh, Pushpindar. "F-16s for Pakistan: Reactions and Views." ''Asian Defence Journal'', September 1981, p. 41.</ref> Northrop felt that the F-5G needed to match the performance of F-16. This would require not only better performance from the engine, but a new and comparable avionics suite as well. Northrop saw that the F-5G was still being viewed as the "FX fighter", a low-cost option for second-tier air forces. To offset this impression, Northrop requested the designation "F-20"; the USAF approved in late 1982, and of the name ''Tigershark'' in March 1983.<ref name=saga/>{{Sfn | Martin | Schmidt | 1987 | p = 15}} Northrop requested to skip [[F-19]], the next available fighter designation, for an even number in order to stand out from the Soviet odd-numbered designations.<ref>Sheffield 1995, p.72</ref>

==Design==
[[File:F-20 cockpit mock-up.jpg|thumb|upright|A mock-up of the prototype cockpit with two multi-function displays and HUD|alt=Mock-up of jet fighter's cockpit, featuring a head-up display behind windshield and displays and dials in front of the pilot.]]

The primary design change between the earlier F-5E and the F-20 was the use of a single [[General Electric F404]] engine, which was originally designed for the F/A-18 Hornet.{{Sfn | Martin | Schmidt | 1987 | p = 4}} The new engine provided 60% more thrust than the combined output of the F-5E's two [[General Electric J85]]s.{{Sfn | Martin | Schmidt | 1987 | p = 12}}  This improved the aircraft's [[thrust-to-weight ratio]] from 1.0 to 1.13. The new engine gave a speed of over Mach 2.0, a ceiling over 55,000&nbsp;ft (16,800&nbsp;m), an initial [[Rate of climb|climb rate]] of 52,800&nbsp;ft per minute (16,100 m/min).<ref name="Donald World Aircraft"/><ref name=Johnsen_p94-6/>

The wing profile remained the same as the F-5E, but had modified [[leading edge extension]]s (LEX), which improved the maximum lift coefficient of the wing by about 12% with an increase in wing area of only 1.6%. The original aircraft was fairly sluggish in pitch, so the horizontal stabilizer was increased in size by 30% and a new dual-channel [[fly-by-wire]] control system was added.  Destabilizing the aircraft in pitch and modifying the LEX improved the instantaneous turn rate by 7% to 20°/sec. Sustained turn rate at Mach&nbsp;0.8 and 15,000&nbsp;ft (4,572&nbsp;m) rose to 11.5°/sec, which compared well with the F-16's 12.8°/sec. Supersonic turn rates were 47% higher than those of the F-5E.

The F-20 would also make greater usage of composite materials in its construction.{{Sfn | Martin | Schmidt | 1987 | p = 4}}  During its development, several areas using metal were re-designed to use [[fiberglass]], and there were numerous upgrades to various mechanical parts.<ref>Anderson, David. [https://books.google.com/books?id=HuMDAAAAMBAJ&pg=PA145 "Why the F-20 isn't selling."] ''Popular Mechanics'', March 1986, p. 145.</ref>

The F-20's avionics suite was all-new and greatly improved over the earlier designs. The [[General Electric AN/APG-67]] multi-mode radar was the heart of the sensor suite, offering a wide range of air-to-air and air-to-ground modes. The F-5's electro-mechanical navigation system was replaced with an all-electronic version based on a [[ring laser gyroscope]]. Time from power-on to takeoff was greatly reduced as a result, to about 22 seconds, and Northrop boasted that the aircraft had the shortest scramble time of any contemporary aircraft.<ref name = "pop mech"/> The cockpit of the F-5 was completely re-worked with a large [[head-up display]] (HUD) and two monochrome multi-function displays set high on the control panel, and the addition of a complete hands-on-throttle-and-stick (HOTAS) control system. Many of the avionics promised to have reliability beyond that of any competing aircraft then in service.<ref>Blinken 1986, p. 95.</ref>

The F-20 would have been able to use most of the common weapons in U.S.'s inventory, including the entire range of [[Mark 80 |Mark 80 series]] bombs, [[AGM-65 Maverick]] air-to-ground missiles, and the AIM-9 Sidewinder and AIM-7 Sparrow air-to-air missiles. Like the earlier F-5s, the test F-20s were equipped with two [[M39 cannon]] mounted in the nose.<ref name=fas20/> Production F-20s may have substituted two [[Ford Aerospace]] [[Tigerclaw]] cannons instead of the M39s; while the Tigerclaw was based on the M39, it was lighter and had a higher rate of fire than the M39A2.<ref>William 2000, p. 78.</ref>

The F-20 did, however, have several problems inherent to its small size. The low-mounted wing meant that there was limited ground clearance, and the position of the [[landing gear]] meant loads had to be positioned towards the outer ends of the wings. This limited [[hard point]] weights to 1,000&nbsp;lb (454&nbsp;kg).<ref name=loadout>[http://www.f20a.com/f20loadout.jpg "F-20 Loadout Chart"] {{webarchive|url= https://archive.today/20110710215414/http://www.f20a.com/f20loadout.jpg |date=10 July 2011 }}, ''Northrop''</ref> A single hard point under the fuselage could carry more, a single [[Mark 84 bomb |Mk 84 2,000 lbs bomb]] or up to five [[Mark 82 bomb |Mk 82 500 lbs bombs]].<ref name=loadout /> Additionally, although the wing profiling improved lift at higher angles of attack (AoA) while maneuvering, it did not improve cruise lift performance at normal AoA.  This did not present a problem in the fighter role, but did severely reduce its payload and range figures compared to similar aircraft like the F-16.<ref name= requiem>{{citation|jstor=2486557|title=Requiem for a Lightweight: The Northrop F-20 Strategic Initiative |journal= Strategic Management Journal|volume=11|issue=1|pages=59–68|last1=Jurkus|first1=Anthony F. |year= 1990 |doi= 10.1002/smj.4250110105}}</ref>

The F-20 was significantly more expensive than the previous generation F-5E.  Among its [[Teen Series]] contemporaries, however, the F-20 was offered as a low-cost option; cost-wise it was estimated in 1983 that the unit fly-away cost of the F-20 (based on a 150-unit buy) was $10.7 million, compared to the F-16/79 at $11 million and the F-16A at $12.4 million.{{cn|date=July 2025}} Unit life-cycle costs for the F-20 estimated as high as 40–50% lower than for the F-16. Another estimate of the F-20's costs found it less expensive than other designs like the $30&nbsp;million F-15 Eagle,<ref>[http://www.af.mil/information/factsheets/factsheet.asp?fsID=101 "F-15 Eagle Fact Sheet."] {{webarchive|url= https://archive.today/20120730162301/http://www.af.mil/information/factsheets/factsheet.asp?fsID=101 |date=30 July 2012 }} ''National Museum of the United States Air Force'', March 2008. Retrieved: 6 August 2008.</ref> or $15&nbsp;million F-16 Fighting Falcon.<ref>[http://www.af.mil/information/factsheets/factsheet.asp?fsID=103 "F-16 Fighting Falcon Fact Sheet."] {{webarchive |url=https://archive.today/20120729011643/http://www.af.mil/information/factsheets/factsheet.asp?fsID=103 |date= 29 July 2012 }} ''National Museum of the United States Air Force'', October 2007. Retrieved: 6 August 2008.</ref> The F-20 was projected to consume 53% less fuel, to require 52% less maintenance manpower, to have 63% lower operating and maintenance costs and to be four times more reliable than average front-line designs of the era.<ref name=fas20>[http://www.fas.org/programs/ssp/man/uswpns/air/fighter/f20.html "F-20 Tigershark."] ''Federation of American Scientists'', 7 June 1999. Retrieved: 13 August 2011.</ref> The F-20 also offered the ability to fire the beyond-visual-range AIM-7 Sparrow missile, a capability that the F-16 lacked at that time, and did not gain until the F-16A/B Block 15 ADF version in February 1989.<ref>David Donald and Jon Lake, Encyclopedia of World Military Aircraft, 1994.</ref>

==Operational history==

===Testing===
[[File:F-20 Tigershark launching AGM-65 Maverick.jpg|thumb|An F-20 launching an [[AGM-65 Maverick]] missile|alt=Gray jet fighter aircraft fires a white missile.]]
On 30 August 1982, the original engine-change-only F-5G (serial 82-0062, c/n GG1001, registered N4416T) made its [[maiden flight]] piloted by Russ Scott.{{Sfn |Dorr|2009|p= 33}} During the 40-minute flight, the prototype climbed to {{convert |40000|ft|m|abbr=on}} and reached Mach 1.04.{{Sfn | Dorr | 2009 | p = 33d}}  GG1001 demonstrated outstanding reliability; by the end of April 1983 240 flights had been accumulated, including evaluation flights with 10 potential customer nations.{{Sfn | Dorr | 2009 | p = 33}}  The second prototype (serial number 82-0063, registered N3986B, c/n GI1001), featuring the complete avionics suite, made its first flight on 26 August 1983.{{Sfn |Dorr|2009|p= 36}}  The F-20 flew 1,500 flights prior to its termination;{{Sfn | Martin | Schmidt | 1987 | p = 6}} although these were exclusively flown in ideal conditions.{{Sfn | Martin | Schmidt | 1987 | p = 25}}  According to the Rand Corporation, "Northrop did not take a prototype approach with the F-20…  The first F-20 was intended to be a production quality aircraft…"<ref>Rand Corporation (report), ''A Case Study of the F-20 Tigershark'', 1987, p. 5.</ref> 

During the test program, the F-20 fired the AIM-9 Sidewinder and, in February 1985 the AIM-7 Sparrow. In air-to-ground testing, it fired the AGM-65 Maverick, 2.75 in (70 mm) folding fin aerial rockets, dropped Mk. 82 bombs, and fired rounds from a 30&nbsp;mm (1.18&nbsp;in) gun pod (GPU-5/A, four-barrel [[GAU-13/A]]) in addition to the two internal 20 mm (.79 in) M39 cannon.<ref name=museum>[http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=2291 "Fact Sheets: Northrop F-20 Tigershark."] {{webarchive|url= https://web.archive.org/web/20150402141325/http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=2291 |date=2 April 2015 }} ''National Museum of the United States Air Force''. Retrieved: 18 July 2011.</ref> One of the F-20's flight characteristics was the ability to fly at only {{convert |124|km/h|mph|abbr= on}} at 35° AoA (angle of attack), while the F-16 was limited to 30°; acceleration from Mach&nbsp;0.9 to 1.2 in 29&nbsp;seconds (at 9,150 m); climb to 12,200 m (or 40,000 ft) in 2.3 minutes (including 55 sec for the start and 22 for the INS set-up).<ref>Sgarlato, Nico. "F-20." ''Aeronautica & Difesa'', February 1988, pp. 47–48.</ref>

[[File:F-20 Northrop colors in flight.jpg|thumb|left|The first F-20 in Northrop colors. |alt=Starboard view of red and white single-engine jet fighter aircraft banking left. At the wingtips are missiles.]]
Northrop signed a [[Memorandum of Agreement]] with the USAF in May 1983 that made the USAF responsible for certifying the F-20's performance, air worthiness and fixed-price program.  Aerospace legend [[Chuck Yeager]], employed as a spokesperson for Northrop, touted the aircraft as "magnificent" and was featured in advertising.<ref name = "pop mech">[https://books.google.com/books?id=HuMDAAAAMBAJ&pg=PA145 "Why the F-20 Isn't Selling."] ''Popular Mechanics'', 163(3), March 1986, p. 145.</ref>{{Sfn | Dorr | 2009 | p = 36}}

In November 1982, Bahrain became the first customer. South Korea also explored local production of the F-20, and in support improvements were implemented. These included avionics upgrades, an expanded fuel tank, and the use of fibreglass composites. The changes were so extensive that a fourth prototype was built to test them. By 1983, Northrop was involved in a number of simultaneous negotiations for the F-20, and its prospects appeared positive.<ref>Lambert, Mark. "Is 1984 the Year of the Tigershark?" ''Interavia'', April 1984, p. 363.</ref>

On 10 October 1984, GG1001 crashed in South Korea on a demonstration flight, killing Northrop pilot [[Darrell Cornell]]. An investigation cleared the F-20 of mechanical or design faults; it concluded Cornell had blacked out due to excessive [[g-force]]s.{{Sfn |Dorr|2009|p= 37}} GI1001 crashed in May 1985 at [[CFB Goose Bay|Goose Bay]], Labrador, killing Northrop pilot Dave Barnes. Again the crash was blamed on [[G-LOC]]; Barnes had been practicing his aerobatic routine for the [[Paris Air Show]].{{Sfn | Martin | Schmidt | 1987 | p = 16}}

===Battle for sales===
In December 1981, President Reagan, reacting to the [[Soviet–Afghan War|Soviet invasion of Afghanistan]], signed a major economic and military aid package for Pakistan that included 40 F-16As.<ref name="singh" /> The offer was in keeping with U.S. policy towards the Soviet Union, and the idea of "[[containment]]" within a ring of U.S.-friendly countries. The Soviet invasion of Afghanistan was initially viewed as an attempt to break out of the arranged containment system, thus the U.S. placed a priority on quickly building up a new layer of defense.<ref>{{citation|jstor=3993537|title='The Red Template': US Policy in Soviet-Occupied Afghanistan|journal=Third World Quarterly|volume=23|issue=3|pages=467–489|last1=Hartman|first1=Andrew|year=2002|doi=10.1080/01436590220138439|s2cid=153553051 }}</ref> However, other U.S. allies saw this as a potential break in the FX policy, and began requesting only "the very best."<ref>Coyne, James. "Trials of the Tigershark." ''Air Force'', January 1985, p. 74.</ref><ref>Martin and Schmidt 1987, pp. 14–15.</ref>

Such approval was increasingly granted starting in 1982.<ref name="MS 21">Martin and Schmidt 1987, p. 21.</ref> In May, Venezuela, who had long examined the FX project, agreed to buy 18 F-16As and six F-16Bs, replacing a fleet of [[Dassault Mirage III|Mirage III]] interceptors and [[Dassault Mirage 5|Mirage 5]] ground-attack aircraft.<ref name="miami cancel">[http://nl.newsbank.com/nl-search/we/Archives?p_product=MH&s_site=miami&p_multi=MH&p_theme=realcities&p_action=search&p_maxdocs=200&p_topdoc=1&p_text_direct-0=0EB366271C4044C8&p_field_direct-0=document_id&p_perpage=10&p_sort=YMD_date:D&s_trackval=GooglePM "Northrop scraps F-20 Fighter: $1.2 Billion 'Mercy Killing'."] ''Miami Herald'', 18 November 1986.</ref> Sweden decided to develop their own design, the [[JAS 39 Gripen]].<ref name="Williams p.72">{{harvnb|Williams et al.|2002|p=72.}}</ref> In September 1983, Turkey announced plans to buy 132 F-16Cs and 28 F-16Ds to replace their Lockheed F-104G/S Starfighter and Northrop F-5A/B.<ref>''New Statesman'', Volume 105, 1983, p. 16.</ref> Greece, stung by its long-time rival receiving the F-16, purchased 34 F-16C and six F-16Ds in November 1984, giving a firm pledge of secrecy.<ref>[https://pqasb.pqarchiver.com/boston/access/659942411.html?FMT=ABS&FMTS=ABS:FT&type=current&date=Jan+14%2C+1986&author=(AP)&pub=Boston+Globe+(pre-1997+Fulltext)&desc=GREECE+GIVES+PLEDGE+IN+BUYING+F-16+JETS&pqatl=google "Greece Gives Pledge in Buying F-16 Jets."] {{Webarchive|url=https://web.archive.org/web/20121107015243/http://pqasb.pqarchiver.com/boston/access/659942411.html?FMT=ABS&FMTS=ABS:FT&type=current&date=Jan+14,+1986&author=(AP)&pub=Boston+Globe+(pre-1997+Fulltext)&desc=GREECE+GIVES+PLEDGE+IN+BUYING+F-16+JETS&pqatl=google |date=7 November 2012 }} ''Boston Globe'', 14 January 1986.</ref>

Then, late in 1983, the U.S. government made a financial commitment to help Israel develop its own new fighter, the [[IAI Lavi]]. Northrop objected to this, as the Lavi would be a potential competitor to the F-20 in the export market; while Northrop had to privately fund the F-20, the government was directly subsidizing a foreign competitor.<ref>"Reagan Approves Credits to Israel for Lavi." ''Aviation Week and Space Technology'', 28 November 1983, pp. 27–49.</ref> Congressional support for Israel overruled Northrop's complaints along with complaints from other branches of the government.<ref>Hunter, Jane. "Israeli Foreign Policy: South Africa and Central America." ''South End Press'', 1987, p. 45.</ref>

While other companies marketed directly to foreign air forces, the F-20 could only be marketed by the State Department as part of the FX program. Under this policy umbrella, Northrop had to submit every piece of marketing material to government review, which could take months. The State Department had no interest in selling the FX; from its perspective it was one aircraft among many, leading to a lackadaisical approach,<ref name=weeksales>Healy, Melissa. "Government Not Vigorous Salesman for Northrop F-20." ''Defense Week'', 2 April 1984, p. 2.</ref> and led to complaints from Northrop that the government was not promoting the F-20 enough.<ref>Pederson 2002, p. 306.</ref>

===Congressional investigation===
Starting in March 1984, Congress chaired a series of hearings into FX. [[William Schneider, Jr.]], the Under Secretary of State for Security Assistance, Science and Technology, testified that FX policy might not result in any sales, in spite of any government support.<ref name=house>''House Subcommittee on International Security and Scientific Affairs and on Asian and Pacific Affairs'', 1984, pp. 14–15.</ref> He stated that the sales of arms such as FX was primarily a matter of foreign policy, secondarily a commercial venture. [[Thomas V. Jones]], Northrop's CEO, argued that there was little point independently developing aircraft if companies were reliant on the government to sell them. He suggested the FX policy be dropped, and F-20 allowed to be sold by the vendor.<ref name=house/> Additionally, Brigadier General Thomas Baker, USAF Director of International Programs, testified that the Air Force was not actively marketing FX.<ref name=weekexports>Kozicharow, Eugene. "USAF Will Increase Export Fighter Role." ''Aviation Week and Space Technology'', 9 April 1984, pp. 20–21.</ref> He observed that over four years the US had sold 100 fighters to 29 countries, none were FX. He also compared France's aircraft exports, showing a market for a low-cost fighter existed. In the Committee's concluding remarks, the State Department and DOD were accused of rhetoric, and lacking support, on FX.<ref name=house/>

In April 1984, after the Congressional hearings, the USAF was directed to promote FX actively. Several potential customers were briefed during May and June 1984 on the performance and cost of both the F-20 and F-16/79.<ref name=weekexports/> The Air Force published an internal report on FX in late June 1984. The F-20 was characterized as having outstanding performance against viable threats; and seen as a candidate for the Air Force's aggressor requirement. The report additionally stated that the F-20 had been contractor-funded, totaling over $750&nbsp;million, compared to $60&nbsp;million on the F-16/79. However, the report concluded that it had little or no market to sell to.<ref>"Policy Statement on FX." ''USAF/PRIP'', 20 June 1984, pp. 1–9.</ref>

===Aggressor and Air National Guard roles===
[[File:F-20 Agressor.jpg|thumb|F-20 "GI1001" carrying its [[Paris Air Show]] identity number "340."|alt=Dark-blue jet aircraft taxiing on ramp, carrying an external fuel tank under belly.]]

A possibility for a U.S. purchase opened in 1984, for a small number of "aggressor aircraft" for [[dissimilar air combat training]]. In November 1984, Congress directed the Air Force and Navy to study the use of a single aircraft type to fill similar aggressor roles for both services.<ref>Healy, Melissa. "Another Shot at Selling Navy 'Red' Fighters." ''Defense Week'', 13 November 1984, p. 10.</ref> In January 1985 the Navy announced they had selected a specially configured version of the F-16. It was rumored that the aircraft was sold at a loss to keep Northrop's F-20 out of the market.<ref>Cole, Stephen. "The End of the F-20?" ''For Your Eyes Only'', 21 January 1985, p. 3.</ref><ref>Martin and Schmidt 1987, pp. 16–17.</ref>

Another chance for the F-20 was as an upgrade for the [[Air National Guard]] (ANG). Northrop claimed that the F-20's fast scramble time made it a natural fit for this role, its lower cost would allow the ANG to operate larger aircraft numbers, and that it supported the AIM-7 while the F-16 did not.<ref>"Guard Studies F-20." ''Aviation Week and Space Technology'', 26 November 1984, p. 17.</ref> However, the Air Force's requirements had priorities favoring the F-16 for the role; if the ANG flew the F-16, they would further lower unit costs, maintain commonality between the ANG and Regular Air Force, and better equip ANG units to perform front line combat roles. The [[Congressional Budget Office]] had also disputed Northrop's lower cost claim in their own research. On 31 October 1986, the Air Force announced that the F-16C had been selected, which had been upgraded to support the AIM-7.<ref>[https://pqasb.pqarchiver.com/projo/access/602720251.html?dids=602720251:602720251&FMT=ABS&FMTS=ABS:FT&type=current&date=Nov+01%2C+1986&author=The+New+York+Times&pub=The+Providence+Journal&desc=Dynamics+wins%2C+Northrop+loses+on+jet+fighters+But+both+will+get+a+chance+to+design+next+generation+of+U.S.+combat+planes&pqatl=google "Dynamics wins, Northrop loses on jet fighters; but both will get a chance to design next generation of U.S. combat planes."] {{Webarchive|url=https://web.archive.org/web/20121107015908/http://pqasb.pqarchiver.com/projo/access/602720251.html?dids=602720251:602720251&FMT=ABS&FMTS=ABS:FT&type=current&date=Nov+01,+1986&author=The+New+York+Times&pub=The+Providence+Journal&desc=Dynamics+wins,+Northrop+loses+on+jet+fighters+But+both+will+get+a+chance+to+design+next+generation+of+U.S.+combat+planes&pqatl=google |date=7 November 2012 }} ''The New York Times'', 1 November 1986.</ref><ref>Martin and Schmidt 1987, pp. 17–18.</ref> As several nations had suggested they would accept the F-20 on the condition that it was inducted into the USAF, the selection was a heavy blow to Northrop.<ref>Yenne 1990, p. 153.</ref>

===Cancellation===

After six years with no buyers, in late 1986 Northrop canceled the $1.2&nbsp;billion project.<ref>Yoshihashi, Pauline.
[https://www.nytimes.com/1986/11/18/business/company-news-northrop-cancels-f-20-fighter-plane.html "Company News: Northrop Cancels F-20 Fighter Plane."] ''[[The New York Times]]'', 18 November 1986, p. 4, section D, column 5.  Retrieved: 13 August 2011.</ref><ref>[http://www.flightglobal.com/pdfarchive/view/1986/1986%20-%203156.html "Northrop quits on F-20."] ''Flight Global,'' 29 November 1986. Retrieved: 12 June 2011.</ref> Northrop was reluctant to protest perceived favoritism of the F-16 in fear of losing support for the [[Northrop Grumman B-2 Spirit]] stealth bomber project.<ref name = "pat 340">Pattillo 2001, p. 340.</ref> Ongoing negotiations with the [[Royal Moroccan Air Force]] for 20 F-20s were canceled;<ref name=museum/> along with the small order by Bahrain.<ref name=Johnsen_p97-8>{{harvnb|Johnsen|2006|pp=97–98.}}</ref> Later on, a bribery scandal would emerge from the attempts to market the F-20 to South Korea, leading to several Northrop managers resigning and the reprimanding of chief executive [[Thomas Victor Jones|Thomas V. Jones]], who retired in 1989.<ref name = "pat 340"/><ref>[https://query.nytimes.com/gst/fullpage.html?res=950DE6DA173FF93AA35756C0A96F948260&n=Top%2fReference%2fTimes%20Topics%2fPeople%2fJ%2fJones%2c%20Thomas%20V%2e  "A Reprimand at Northrop."] ''The New York Times'', 8 March 1989.</ref><ref>Clinard 1990, p. 126.</ref>

In the late 1980s, local production of the F-20 was discussed with India. A move was also made in the 1980s to market the aircraft to the Pakistan Air Force with a license production manufacture of the aircraft. It was evaluated by a Pakistani contingent in the United States, with the F-20 being flown by Abbas Mirza, a senior Pakistani Air Force fighter pilot.<ref>Ganguly, Sumit. [https://pqasb.pqarchiver.com/csmonitor_historic/access/175428182.html?dids=175428182:175428182&FMT=ABS&FMTS=ABS:AI&date=Jan+05%2C+1987&author=By+Sumit+GangulySumit+Ganguly+is+assistant+professor+of+Political+Science+at+Hunter+College%2FCUNY+and+author+of+%22The+Origins+of+War+in+South+Asia%3A+The+Indo-Pakistani+Conflicts+Since+1947.%22&pub=Christian+Science+Monitor&desc=India+and+the+US%3A+they're+building+new+defense+ties&pqatl=google "India and the US: they're building new defense ties."] {{Webarchive|url= https://web.archive.org/web/20120725105034/http://pqasb.pqarchiver.com/csmonitor_historic/access/175428182.html?dids=175428182%3A175428182&FMT=ABS&FMTS=ABS%3AAI&date=Jan+05%2C+1987&author=By+Sumit+GangulySumit+Ganguly+is+assistant+professor+of+Political+Science+at+Hunter+College%2FCUNY+and+author+of+%22The+Origins+of+War+in+South+Asia%3A+The+Indo-Pakistani+Conflicts+Since+1947.%22&pub=Christian+Science+Monitor&desc=India+and+the+US%3A+they%27re+building+new+defense+ties&pqatl=google |date=25 July 2012 }} ''Christian Science Monitor'', 5 January 1987.</ref> Of the components of the F-20, the radar would end up being the most successful; Taiwan selected it for the Ching-kuo, South Korea also adopted it for the [[KAI T-50 Golden Eagle]] [[trainer aircraft]]. As sales prospects were not apparent early on, GE sold their radar division, which was eventually acquired by [[Lockheed Martin]].<ref>[http://www.lockheedmartin.com/data/assets/7729.pdf "APG-67 Multimode Radar."] {{webarchive|url= https://web.archive.org/web/20110525130205/http://www.lockheedmartin.com/data/assets/7729.pdf |date=25 May 2011 }} ''Lockheed Martin Maritime Systems and Sensors'', B0201-APG-67 (SA) 03/04. Retrieved: 6 August 2008.</ref>

Aviation author Steve Pace wrote of the F-20 as "one of the best fighters that never went into production."{{Sfn | Pace | 2003 | p = 89}}  While discussing military procurement, Thomas McNaugher stated that competition between the F-20 and the F-16 served to lower prices and generate "massive savings" for the U.S. government.{{Sfn | McNaugher | 1989 | pp = 171–73}}  Writing prior to cancellation, Ralph Nader and William Taylor noted that the F-20 had been commonly described as "the first privately funded U.S. combat aircraft in recent history."{{Sfn | Nader | Taylor | 1986 | p = 386}}  Mazher A. Hameed commented in 1986 that the F-20 was a "logical choice" for the Gulf States and Saudi Arabia; however, it had "scant chance of being selected" due to political factors, as well as competition from other candidates such as the Mirage 2000 and [[Panavia Tornado ADV]].{{Sfn | Hameed | 1986 | p = 128}}

==Aircraft disposition==
{{multiple image
| align = right
| image1 = F-20 Tigershark display at California Science Center Los Angeles.jpg
| width1 = 250
| alt1 =
| caption1 =
| image2 = F-20 Tigershark at California Science Center Los Angeles right side.JPG
| width2 = 250
| alt2 =
| caption2 =
| footer = The remaining F-20 is on display at the California Science Center in Los Angeles.
}}
* 82-0062 (Northrop serial number GG.1001) – crashed at [[Suwon Air Base]], [[South Korea]] on 10 October 1984. Pilot killed.<ref name=Baugher1982>[http://www.joebaugher.com/usaf_serials/1982.html "F-20 Tigershark/82-0062."] ''Joe Baugher's serial numbers.'' Retrieved: 10 May 2013.</ref>
* 82-0063 (Northrop serial number GI.1001) – crashed at [[CFB Goose Bay]], [[Canada]] on 14 May 1985. Pilot killed.<ref name=Baugher1982 />
* 82-0064 (Northrop serial number GI.1002) – [[California Science Center]] in [[Exposition Park (Los Angeles)|Exposition Park]], [[Los Angeles, California]].<ref>[http://www.californiasciencecenter.org/Exhibits/AirAndSpace/AirAndAircraft/F20/F20.php "F-20 Tigershark/82-0064."] ''California Science Center''. Retrieved: 6 August 2008.</ref>

==Specifications (F-20)==
{{Aircraft specs
|ref= ''Northrop F-5/F-20/T-38'',<ref name= Johnsen_p94-6>{{harvnb|Johnsen|2006|pp= 94, 96.}}</ref> ''Complete Encyclopedia of World Aircraft'',<ref name="Donald World Aircraft"/> Jane's All the World's Aircraft 1984–85<ref name= JAWA84-85>{{cite book |title= All the World's Aircraft 1984–85 |url= https://archive.org/details/janesallworldsai8485john |url-access= registration |editor1-last=Taylor |editor1-first=John W.R. |edition=75th |year= 1984 |publisher=Jane's |location= London |isbn= 0-7106-0801-2 |page= 463}}</ref>
|prime units?=kts
<!--
        General characteristics
-->
|crew=1
|length ft=47
|length in=4
|length note=
|span ft=27
|span in=11.875
|span note=with wing-tip missiles
::::{{cvt|26|ft|8|in|2}} clean
|height ft=13
|height in=10.25
|height note=
|aspect ratio=<!-- sailplanes -->
|airfoil=[[NACA airfoil|NACA 65A004.8 modified]]<ref name="Selig">{{cite web |last1=Lednicer |first1=David |title=The Incomplete Guide to Airfoil Usage |url= https://m-selig.ae.illinois.edu/ads/aircraft.html |website= Selig | publisher = U Illinois |access-date= 16 April 2019}}</ref>
|empty weight lb=11810
|empty weight note=
|gross weight lb=16015
|gross weight note= '''Combat TOW''' - 50% fuel 2x AIM-9
|max takeoff weight lb=27500
|max takeoff weight note=
|fuel capacity={{cvt|5050|lb|0}} in integral and bladder tanks
|more general=
<!--
        Powerplant
-->
|eng1 number=1
|eng1 name=[[General Electric F404-GE-100]]
|eng1 type=afterburning turbofan engine
|eng1 lbf=11000
|eng1 note=
|eng1 lbf-ab=17000

<!--
        Performance
-->
|max speed kts=1147
|max speed note=
|max speed mach=2
|cruise speed kts=
|cruise speed note=
|stall speed kts=
|stall speed note=
|never exceed speed kts=
|never exceed speed note=
|minimum control speed kts=
|minimum control speed note=
|range nmi=320
|range note= in '''air superiority mission''' with 2 × AIM-9 and 5 minutes air combat
::::{{cvt|150|nmi|mi km}} in '''close air support''' with 2 × [[AIM-9 Sidewinder|AIM-9]] + 7 × [[Mk 82 bomb|Mk 82]]s + 2 × {{cvt|330|USgal|impgal l}} drop tanks
::::{{cvt|300|nmi|mi km}} in '''combat air patrol''' with 2 × AIM-9 + 3 × {{cvt|330|USgal|impgal l}} drop tanks, 138 minutes on station + 20 minutes reserve
::::{{cvt|550|nmi|mi km}} for '''hi-lo-hi interdiction''' with 2 × AIM-9 + 5 × Mk 82 + 2 × {{cvt|330|USgal|impgal l}} drop tanks<ref name = FAS>{{cite web|url=https://fas.org/man/dod-101/sys/ac/f-20.htm |publisher = Federation of American Scientists |title=F-20 Tigershark|date=7 June 1999}}</ref>
|combat range nmi=
|combat range note=
|ferry range nmi=2015
|ferry range note=with full internal fuel and 3 × {{cvt|330|USgal|impgal l}} drop tanks
|endurance=<!-- if range unknown -->
|ceiling ft=56800
|ceiling note=<br>
*'''Combat ceiling:''' {{cvt|15000|ft|0}}
|g limits=<big>+</big>9
|roll rate=<!-- aerobatic -->
|glide ratio=<!-- sailplanes -->
|climb rate ftmin=
|climb rate note=
|time to altitude=
|sink rate ftmin=<!-- sailplanes -->
|sink rate note=
|lift to drag=
|wing loading lb/sqft=
|wing loading note=
|disk loading lb/sqft=
|disk loading note=
|fuel consumption lb/mi=
|power/mass=1.1
|thrust/weight=

|more performance=<br/>
*'''Sustained turn rate:''' 13.2°/s at M0.8 at {{cvt|15000|ft|0}}
*'''Take-off run:''' {{cvt|1425|ft|0}}
*'''Take-off run at MTOW:''' {{cvt|3550|ft|0}}
*'''Landing run:''' {{cvt|2150|ft|0}}
<!--        Armament -->
|guns=2 × [[20 mm caliber|20 mm (0.79 in)]] [[M39 cannon|Pontiac M39A3 cannons]] in the nose, 280 rounds each and a General Electric 30 mm gun pod which can be mounted on the fuselage
|hardpoints= 7 external [[hardpoint]]s
|hardpoint capacity= 8,000 lb (3,600 kg) of bombs, missiles, rockets, gun pods and up to 3 [[drop tank]]s for extended range
|rockets=2 × [[CRV7]] rocket pods ''or''<br /> 2 × LAU-10 rocket pods with 4 × [[Zuni (rocket)|Zuni]] 5 in (127 mm) rockets each ''or''<br />2 × Matra rocket pods with 18 × [[SNEB]] 68 mm rockets each
|missiles=2 × [[AIM-9 Sidewinder]]s on wing tip launch rails (similar to F-16 and F/A-18)<br />Up to 2 × [[AIM-7 Sparrow]]s or 4 × [[AIM-120 AMRAAM]]s{{Citation needed|reason=Only photos of F-20 with mockup AMRAAM dummy are available, requesting source for actual integration of AIM-120 on the F-20|date=February 2025}} or 4 × [[AIM-9 Sidewinder]]s on underwing hardpoints or <br>4 × [[AGM-65 Maverick]] [[air-to-surface missile]]s on underwing hardpoints <ref>{{cite web|url=https://nationalinterest.org/blog/buzz/f-20-tigershark-greatest-fighter-plane-us-military-passed-208621.htm | work = The National Interest|title=F-20 Tigershark|date=16 January 2024}}</ref><ref>{{cite web|url=https://www.youtube.com/watch?v=Q_VcNlOTu8g.htm |publisher = Periscope Film |title= Northrop F-20 Tigershark Sales Film |date=9 November 2015}}</ref><ref>{{cite web|url= https://www.youtube.com/watch?v=6BDgQwlfHII.htm |publisher = Puzzling Evidence TV|title=F-20 Tigershark Aircraft Sales Film |date= 23 January 2011}}</ref>
|bombs= Various air-to-ground ordnance such as [[Mark 80|Mark 80 series]] of unguided [[gravity bomb|iron bombs]] (including 3&nbsp;kg and 14&nbsp;kg practice bombs), [[CBU-24]]/49/52/58 cluster bomb munitions, M129 Leaflet bomb
|avionics=
* [[General Electric]] [[AN/APG-67]]
}}

==See also==
{{Portal|Aviation}}
{{aircontent
|see also=
|related=
* [[Northrop F-5]]
* [[Northrop T-38 Talon]]
|similar aircraft=
* [[AIDC F-CK-1 Ching-kuo]]
* [[HAL Tejas]]
* [[CAC/PAC JF-17 Thunder]]
* [[General Dynamics F-16 Fighting Falcon]] (Block 10)
|lists=
* [[List of military aircraft of the United States]]
* [[List of fighter aircraft]]
}}

==References==
{{reflist}}

===Bibliography===
{{Refbegin}}
* {{Cite book |last=Binkin |first=Martin |url=https://archive.org/details/militarytechnolo00bink/page/95 |title= Military Technology and Defense Manpower |publisher=[[Brookings Institution]] |year=1986 |isbn=978-0-81570977-0 |location= Washington, DC |oclc=230837024 |url-access=registration}}
* {{Cite book |last=Clinard |first=Marshall Barron |url=https://archive.org/details/corporatecorrupt1990clin/page/126 |title= Corporate Corruption: The Abuse of Power |publisher=Praeger |year=1990 |isbn=978-0-275-93485-9 |location=New York |oclc= 20418391 |url-access=registration}}
* {{Citation | editor-last = Donald | editor-first = David | title = Northrop F-5 family. Northrop F-20A Tigershark | encyclopedia = The Complete Encyclopedia of World Aircraft | place = New York | publisher = Barnes & Noble Books | year = 1997 | isbn = 0-7607-0592-5}}.
* {{Cite book |last=Dorr |first=Robert F |url=https://www.defensemedianetwork.com/stories/what-might-have-been-f-20-tigershark/ |title=Aircraft |chapter=What Might Have Been: F-20 Tigershark |place=London |publisher=Ian Allan Publishing |date= November 2009 |issn=2041-2150 |pages=32–38}}
* {{Cite book |last=Hameed |first=Mazher A. |url=https://archive.org/details/arabiaimperilled0000hame/page/128/ |title= Arabia Imperilled: The Security Imperatives of the Arab Gulf States |publisher=Middle East Assessments Group |year=1986 |isbn= 0-70994663-5 |location=Washington, DC |url-access=registration}}
* {{Citation | last = Inbar | first = Efraim | title = Israel's National Security: Issues and Challenges since the Yom Kippur War | place = London | publisher = Routledge | year = 2008 | isbn = 978-0-415-44955-7}}.
* {{Cite book|last=Johnsen|first=Frederick A|title=Northrop F-5/F-20/T-38|location=North Branch, [[Minnesota|MN]] | publisher =Specialty Press |year= 2006 |isbn=1-58007-094-9}}
* {{Cite book |last1=Martin |first1=Tom |url=http://www.rand.org/pubs/papers/2009/P7495.pdf |title= A Case Study of the F-20 Tigershark |last2=Schmidt |first2=Rachel |date=June 1987 |publisher=[[RAND Corporation]] |oclc=831956260|archive-url= https://web.archive.org/web/20120417130648/http://www.rand.org/pubs/papers/2009/P7495.pdf |archive-date=17 April 2012 }}
* {{Citation | last = McNaugher | first = Thomas L | url = https://books.google.com/books?id=MgFPwnOxIC0C | title = New Weapons, Old Politics: America's Military Procurement Muddle | place = Washington, DC | publisher = Brookings Institution Press | year = 1989 | isbn = 0-8157-5625-9}}.
* {{Cite book |last1=Nader |first1=Ralph |url=https://archive.org/details/bigboyspower00nade_0/page/361 |title=The Big Boys: Power and Position in American Business |last2=Taylor |first2=William |publisher=Pantheon Books |year=1986 |isbn= 978-0-39453338-4 |location=New York |oclc=12803728 |author-link=Ralph Nader |url-access=registration}}
* {{Cite book |last=Pace |first=Steve |url=https://archive.org/details/xplanespushingen0000pace/page/89 |title=X-Planes: Pushing the Envelope of Flight |publisher=MBI Pub. |year=2003 |isbn=978-0-76031584-2 |location=St. Paul, MN |url-access= registration}}
* {{Citation | last = Pattillo | first = Donald M | title = Pushing the Envelope: The American Aircraft Industry | place = Ann Arbour, [[Michigan|MI]] | publisher = University of Michigan Press | year = 2001 | isbn = 0-472-08671-5}}.
* {{Citation | last = Pederson | first = Jay P | title = International Directory of Company Histories | volume = 45 | place = London | publisher = St. James Press | year = 2002 | isbn = 1-55862-463-5}}.
* {{cite book| last = Shefield | first = Richard G. | title = Lockheed F-117 Nighthawk | publisher = Aerospace | year = 1995 | page = 72 | isbn = 978-1880588192 }}
* {{Citation | last = Thornton | first = Richard C | url = https://books.google.com/books?id=pTpKIFq3X_EC | title = The Reagan Revolution II: Rebuilding the Western Alliance | place = Bloomington, [[Indiana|IN]], USA | publisher = Trafford Publishing | year = 2004 | isbn = 1-4120-1356-9}}.
* {{Cite book |editor-last= Williams|editor-first=Mel|title=Superfighters: The Next Generation of Combat Aircraft | location = London|publisher=AIRtime Publishing |year= 2002 |isbn=1-880588-53-6|ref={{harvid|Williams et al.|2002}}}}
* {{Cite book |last=Yenne |first=Bill |url=https://archive.org/details/worldsworstaircr0000yenn/page/152 |title= The World's Worst Aircraft |publisher=Dorset Press |year=1993 |isbn=978-0-88029490-4 |pages=152–53 |oclc= 610298648 |url-access= registration}}
{{Refend}}

==Further reading==
* {{Cite book |last=Crosby |first=Francis |url=https://archive.org/details/fighteraircraftf0000cros/page/224 |title=Fighter Aircraft |location=London |page=224 |oclc=50067188 |url-access=registration |publisher=Lorenz Books |year=2002 |isbn=0-7548-0990-0|ref=none}}
* {{Cite book |last1=Dorr |first1=Robert F. |url=https://archive.org/details/fightersofunited0000dorr/page/218/ |title=Fighters of the United States Air Force: From World War I Pursuits to the F-117 |last2=Donald |first2=David |publisher=Temple |year=1990 |isbn=9780600550945 |pages=218–219 |oclc=24741367 |url-access=registration|ref=none}}
* Jenkins, Dennis R. and Tony R. Landis. ''Experimental & Prototype U.S. Air Force Jet Fighters''. St. Paul, Minnesota: Specialty Press, 2008. {{ISBN|978-1-58007-111-6}}.
* Pace, Steve. ''X-Fighters: USAF Experimental and Prototype Fighters, XP-59 to YF-23''. St. Paul, [[Minnesota|MN]]: Motorbooks International, 1991. {{ISBN|0-87938-540-5}}.
* {{Cite book |last=Scutts |first=Jerry |title=Northrop F-5/F-20 |publisher=Ian Allan |year=1986 |isbn=9780711015760 |location=London |oclc=15806562|ref=none}}
* {{Cite book |last=Shaw |first=Robbie |url=https://archive.org/details/f5warplaneforwor0000shaw/page/n11 |title=F-5, Warplane for the World |publisher=Motorbooks International |year=1990 |isbn=9780879384876 |location=Osceola, WI |oclc=22344704 |url-access=registration|ref=none}}
* Williams, Anthony G. ''Rapid Fire: The Development of Automatic Cannon, Heavy Machine Guns and their Ammunition for Armies, Navies and Air Forces''. Shrewsbury, UK: Airlife Publishing, 2003. {{ISBN|1-84037-435-7}}.

==External links==
{{Commons|Northrop F-20 Tigershark}}
* [https://patents.justia.com/patent/D285062 "Aircraft," US Patent D285062]
* [https://web.archive.org/web/20150402141325/http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=2291 National Museum of the United States Air Force]
* [https://www.youtube.com/watch?v=DpPXIhhHG3E&t=93s Chuck Yeager in the F-20 (YouTube)]
* [https://vdocuments.mx/ntm-1f-20a-1-northtrop-f-20a-aircraft-utility-flight-manual.html (1984) NTM 1F-20A-1 Northrop F-20A Aircraft Utility Flight Manual]

{{F-5 family}}
{{Northrop aircraft}}
{{US fighters}}

[[Category:Northrop aircraft|F-020 Tigershark]]
[[Category:1980s United States fighter aircraft]]
[[Category:Single-engined jet aircraft]]
[[Category:Low-wing aircraft]]
[[Category:Cancelled military aircraft projects of the United States]]
[[Category:Aircraft first flown in 1982]]
[[Category:Fourth-generation jet fighters]]