Editing Northrop F-5 (section)

===United States===
[[File:F-5B 602TFS BienHoa 1966.jpg|thumb|left|An F-5B of 602d TFS at Bien Hoa, 1966]]

The F-5 entered service with the USAF's 4441st Combat Crew Training Squadron at [[Williams Air Force Base]], which had the role of training pilots and ground crew for customer nations, including Norway, on 30 April 1964. At that point, it was still not intended that the aircraft be used in significant numbers by the USAF itself.<ref name="WAPJ 25 p53">{{harvnb|Lake|Hewson|1996|p=53}}</ref>

USAF doctrine with regard to the F-5 changed following operational testing and limited deployment in 1965. Preliminary combat evaluation of the F-5A began at the [[Air Proving Ground Center]], [[Eglin Air Force Base]], Florida, in mid-1965 under the code name Project ''Sparrow Hawk''. One airframe was lost in the course of the project, through pilot error, on 24 June.<ref>Plunkett, W. Howard. "When the Thunderbirds Flew the Thunderchief." ''Air Power History,'' Air Force Historical Foundation, Clinton, Maryland, Fall 2009, Volume 56, Number 3, pp. 24–25.</ref>

In October 1965, the USAF began a five-month combat evaluation of the F-5A titled ''Skoshi Tiger''. A total of 12 aircraft were delivered for trials to the 4503rd Tactical Fighter Squadron, and after modification with probe and drogue [[aerial refueling]] equipment, armor and improved instruments, were redesignated ''F-5C''.<ref name="WoF 5 p4-6">{{harvnb|Thompson|1996|pp=4–6}}.</ref> Over the next six months, they flew in combat in the [[Vietnam War]], flying more than 2,600 sorties, both from the [[3rd Tactical Fighter Wing]] at [[Bien Hoa Air Base]] over South Vietnam and from [[Da Nang Air Base]], where operations were flown over [[Laos]]. Nine aircraft were lost in Vietnam, seven to enemy ground fire and two to operational causes.<ref>Hobson p. 43, 64, 70, 71, 73, 75, 83, 90, 268</ref><ref name="WoF 5 p12,14">{{harvnb|Thompson|1996|pp= 12, 14}}.</ref>

Operations were declared a success, with the F-5 generally rated as being as capable a ground-attacker as the F-100, albeit having a shorter range.<ref name="WoF 5 p16">{{harvnb|Thompson|1996|p=16}}.</ref> However, the program was more a political gesture that was intended to aid the export of F-5s than a serious consideration of the type for US service.<ref name="WoF 5 p4-6"/>{{Disputed inline|Skoshi Tiger|date=March 2025}} (Following ''Skoshi Tiger'' the [[Philippine Air Force]] acquired 23 F-5A and B models in 1965. These aircraft, along with remanufactured [[Vought F-8 Crusader]]s, eventually replaced the Philippine Air Force's F-86 Sabres in the air defense and ground attack roles.){{cn|date=March 2025}}

From April 1966, the USAF aircraft continued operations under the auspices of the [[10th Fighter Squadron, Commando]], with their number boosted to 17 aircraft.{{cn|date=March 2025}}

[[File:Northrop F-5F (Tail No. 00889) 061006-F-1234S-083.jpg|thumb|USAF F-5F with [[AIM-9 Sidewinder|AIM-9J Sidewinder]], [[AGM-65 Maverick]] missiles and auxiliary fuel tanks over [[Edwards Air Force Base]], 1976.]]
In June 1967, the surviving aircraft of the 10th Fighter Squadron, Commando, were transferred to the [[Republic of Vietnam Air Force]] (RVNAF). In view of the performance, agility and size of the F-5, it might have appeared to be a good match against the similar MiG-21 in air combat; however, US doctrine was to use heavy, faster and longer-range aircraft like the [[Republic F-105 Thunderchief]] and McDonnell Douglas F-4 Phantom II over North Vietnam.{{cn|date=March 2025}}

The F-5 was also adopted as an opposing forces (OPFOR) "aggressor" for dissimilar training role because of its small size and performance similarities to the Soviet MiG-21. In realistic trials at Nellis AFB in 1977, called [[ACEVAL/AIMVAL]], the F-14 reportedly scored slightly better than a 2:1 kill ratio against the simpler F-5, while the F-15 scored slightly less.<ref>{{harvnb|Gervasi|1981|p=123}}.</ref><ref>{{harvnb|Auten|2008|p=390}}</ref><ref>{{harvnb|Gilcrist|1994|p=95}}.</ref><ref>{{harvnb|Lake|1998|p=85}}.</ref> There is some contradiction of these reports, another source reports that "For the first three weeks of the test, the F-14s and F-15s were hopelessly outclassed and demoralized"; after adapting to qualities of the F-5 carrying the new all aspect AIM-9L missile and implementing rule changes to artificially favor long range radar-guided missiles, "the F-14s did slightly better than breaking even with the F-5s in non-1 v 1 engagements; the F-15s got almost 2:1".<ref>Sprey 1972, p. 140.</ref> A 2012 [[Discovery Channel]] documentary ''Great Planes'' reported that in USAF exercises, F-5 aggressor aircraft were competitive enough with more modern and expensive fighters to only be at small disadvantage in Within Visual Range (WVR) combat.<ref>[https://www.youtube.com/watch?v=qMBXJFHUrPo "Northrop F-5 Freedom Fighter."] {{Webarchive|url=https://web.archive.org/web/20140304015646/http://www.youtube.com/watch?v=qMBXJFHUrPo |date=4 March 2014}} ''Great Planes episode, Discovery Channel'', May 2012.</ref>

[[File:170125-M-PL134-005.jpg|thumb|USMC F-5N Tiger IIs from [[VMFT-401]] on standby at the [[Marine Corps Air Station Beaufort]]]]
The F-5E served with the US Air Force from 1975 until 1990, in the [[64th Aggressor Squadron]] and [[65th Aggressor Squadron]] at [[Nellis Air Force Base]] in [[Nevada]], and with the 527th Aggressor Squadron at RAF Alconbury in the UK and the [[26th Space Aggressor Squadron|26th Aggressor Squadron]] at [[Clark Air Force Base]] in the Philippines. The US Marines purchased used F-5s from the Air Force in 1989 to replace their [[IAI Kfir|F-21s]], which served with [[VMFT-401]] at [[Marine Corps Air Station Yuma]]. The US Navy used the F-5E extensively at the [[Naval Fighter Weapons School]] (TOPGUN) when it was located at [[NAS Miramar]], California. When TOPGUN relocated to become part of the [[Naval Strike and Air Warfare Center]] at [[NAS Fallon]], Nevada, the command divested itself of the F-5, choosing to rely on VC-13 (redesignated [[VFC-13]] and which already used F-5s) to employ their F-5s as adversary aircraft. Former adversary squadrons such as [[VF-43]] at [[NAS Oceana]], [[VF-45 (1963-96)|VF-45]] at [[NAS Key West]], [[VF-126]] at NAS Miramar, and [[VFA-127]] at [[NAS Lemoore]] have also operated the F-5 along with other aircraft types in support of Dissimilar Air Combat Training (DACT).{{cn|date=March 2025}}

The US Navy F-5 fleet continues to be modernized with 36 low-hour F-5E/Fs purchased from Switzerland in 2006. These were updated as F-5N/Fs with modernized avionics and other improved systems. Currently, the only US Navy and US Marine Corps units flying the F-5 are VFC-13 at NAS Fallon, Nevada, [[VFC-111]] at NAS Key West, Florida and VMFT-401 at MCAS Yuma, Arizona.<ref name="USN F-5N">[http://www.navy.mil/navydata/fact_display.asp?cid=1100&tid=1050&ct=1 "F-5N/F Adversary aircraft fact file."] {{Webarchive|url=https://web.archive.org/web/20080307205706/http://www.navy.mil/navydata/fact_display.asp?cid=1100&tid=1050&ct=1 |date=7 March 2008}} ''U.S. Navy''. Retrieved: 15 May 2010.</ref> Currently, VFC-111 operates 18 Northrop F-5N/F Tiger IIs.  17 of these are single-seater F-5Ns and the last is a twin-seater F-5F "FrankenTiger", the product of grafting the older front-half fuselage of an F-5F into the back-half fuselage of a newer low-hours F-5E acquired from the Swiss Air Force. A total of three "FrankenTigers" were made.<ref name="AFM283">Ted, Carlson. "One-Eleven Heaven" ''[[AirForces Monthly]]'' ([[Key Publishing]]), Issue 283, October 2011, p. 48. {{ISSN|0955-7091}}. Retrieved: 10 October 2011.</ref>

According to the [[FAA]], there are 18 privately owned F-5s in the US, including Canadair CF-5Ds.<ref>[http://registry.faa.gov/aircraftinquiry/AcftRef_Results.aspx?Mfrtxt=NORTHROP&Modeltxt=F-5&PageNo=1 "FAA Registry: Northrop F-5."] {{Webarchive|url=https://web.archive.org/web/20120818125228/http://registry.faa.gov/aircraftinquiry/AcftRef_Results.aspx?Mfrtxt=NORTHROP&Modeltxt=F-5&PageNo=1 |date=18 August 2012}} ''FAA''. Retrieved: 17 May 2011.</ref><ref>[http://registry.faa.gov/aircraftinquiry/AcftRef_Results.aspx?Mfrtxt=CANADAIR&Modeltxt=F-5&PageNo=1 "FAA Registry: Canadair F-5."] {{Webarchive|url=https://web.archive.org/web/20120818125247/http://registry.faa.gov/aircraftinquiry/AcftRef_Results.aspx?Mfrtxt=CANADAIR&Modeltxt=F-5&PageNo=1 |date=18 August 2012}} ''FAA''. Retrieved: 17 May 2011.</ref>