Northrop (Canadair) NF-5B Freedom Fighter (K-4011) as used by the "Koninklijke Luchtmacht" (RNLAF)
at the Military Aviation Museum, Kamp Zeist (the Netherlands)

The Northrop F-5A/B Freedom Fighter and the F-5E/F Tiger II are part of a supersonic light fighter family, initially designed in the late 1950s by Northrop Corporation. Being smaller and simpler than contemporaries such as the McDonnell Douglas F-4 Phantom II, the F-5 cost less to both procure and operate, making it a popular export aircraft. The F-5 started life as a privately funded light fighter program by Northrop in the 1950s. The design team wrapped a small, highly aerodynamic fighter around two compact and high-thrust General Electric J85 engines, focusing on performance and low cost of maintenance. Though primarily designed for the day air superiority role, the aircraft is also a capable ground-attack platform. The F-5A entered service in the early 1960s. During the Cold War, over 800 were produced through 1972 for United States allies. Though the United States Air Force (USAF) had no acknowledged need for a light fighter, it did procure roughly 1200 Northrop T-38 Talon trainer aircraft, which were directly based on the F-5A. After winning the International Fighter Aircraft competition in 1970, a program aimed at providing effective low-cost fighters to American allies, Northrop introduced the second-generation F-5E Tiger II in 1972. This upgrade included more powerful engines, higher fuel capacity, greater wing area and improved leading edge extensions for a better turn rate, optional air-to-air refuelling, and improved avionics including air-to-air radar. Primarily used by American allies, it was also used in the United States training exercises. A total of 1400 Tiger IIs were built before production ended in 1987. More than 3800 F-5 and T-38 aircraft were produced in Hawthorne, California, United States.

In Canada the F-5 was license built by Canadair as the CF-5 (CF-116 with the Canadian Air Force), and with their terms and cooperation with
Fokker and others, the Royal Netherlands Air Force (RNLAF) decided to order 75 F-5A's en 30 F-5B's. Parts built in the Netherlands were assembled in Canada, resulting in the NF-5A and NF-5B. An eyecatching improvement were leading edge slats, improving manoeuvrability. An arrestor hook was fitted, as was a strengthened windscreen to prevent damage from bird hits. Many of these changes and improvements later found their way into the F-5E Tiger II. The Royal Netherlands Air Force took delivery of its first aircraft (an NF-5B two-seater) in October 1969, with the first squadron to be formed was 313 Squadron at Twenthe, the Netherlands. Initial role of 313 Squadron was a conversion unit to train pilots on the new type. The NF-5 would serve with four operation squadrons, 313 and 315 Squadron at Twenthe, 316 Squadron at Gilze-Rijen and 314 Squadron at Eindhoven.
The last NF-5 was delivered in March 1972. From 1986 the squadrons began to convert to the licence-built General Dynamics F-16 Fighting Falcon and the last NF-5 was stood down in March 1991. Most surplus aircraft were sold to Turkey and Venezuela or retained for spares support,
a number of aircraft were given free to Greece.