F-5 Freedom Fighter / Tiger II

Northrop had been known for large fighters since its wartime P-61 Black Widow, a trend that had continued postwar with the F-89 Scorpion and various unbuilt designs. However, by the early 1950s the pendulum had begun to swing the other way. While the "Century Series" fighters were increasingly complex, Northrop foresaw that many potential export customers would not have the funding to procure or operate such aircraft. Thus, a team under P-51 designer Edgar Schmued began work on an aircraft that would combine high performance and affordability.

The N-102 Fang was a compact aircraft concept built around a single large engine. The preferred engine was GE's new J79, but the Pratt & Whitney J57 or Wright J65 could also be used The N-102 had a tailed delta configuration; unusually, the tailplane was at the same level as the wings. Northrop also investigated a v-tail design. The N-102 would have had a basic armament of an M61 Vulvan cannon and ordnance on six hardpoints. A two-seat version with a slightly stretched fuselage was also proposed.

The N-102 project progressed to the mockup stage, but no Fangs were ever to take to the air, as it was recognized that the lack of internal volume would restrict future growth. The lightweight fighter concept was far from dead, however and even before the Fang was canceled Northrop was working on the N-156, a small twin-engined design with a T-tail. This would have been capable of operating from small CVE escort carriers, but the US Navy did not show serious interest. Northrop would then re-use the N-156 project designator for another lightweight fighter, one that would be in production for the next three decades.

The "new" N-156 would be powered by a pair of GE J85s; the revised concept was actually composed of two distinct variants, the N-156F fighter, and the N-156T operational trainer. The latter was actually the first of the family to fly, as the USAF had a requirement for a supersonic trainer. The N-156T was bought as the T-38 Talon, and this helped keep the N-156F concept alive.

The N-156F was similar to the T-38, but had larger intakes, maneuvering flaps, and a pair of 20mm M39 cannon. The fighter prototype first flew in July 1959, but the program appeared stalled until 1962, when the type was selected by the USAF for supply to friendly countries, with the aircraft being named the F-5 Freedom Fighter.

Canadair would build the F-5A under license as the CF-5/CF-116 for domestic Canadian use, and as the NF-5 for the Dutch. CASA also constructed Freedom Fighters, as the C.9 / SF-5. The F-5A(G) version for Norway had a number of special features to cope with the rigors of operating in far northern climates, including an arrester hook and JATO provisions for taking off from icy runways. Despite their age, the Norwegian F-5As still had some life left in the early 1990s, and fifteen were given avionics upgrades under the Tiger PAWS program for service as trainers for the Norwegian F-16 force.

Despite there already being a two-seat version of the N-156 design in the form of the T-38, there was also the need for a more operationally oriented trainer variant for F-5 operators, and this was to take the form of the F-5B. This model retained the wingtip Sidewinder rails and underwing hard points, but the necessary rearrangement of systems to allow for the second cockpit took up the volume normally occupied by the cannon.

The F-5C designation referred to a small number of F-5As sent to South Vietnam in 1965 as part of the Skoshi Tiger evaluation program. The F-5Cs were fitted with armor, and fixed refueling probes compatible with Navy tankers and KC-135s equipped with drogue adapters. These flew over 3,500 sorties, and proved to be well-suited for combat in Southeast Asia. The F-5Cs were later turned over to the South Vietnamese Air Force, becoming that service's first supersonic aircraft.

Design of a second-generation F-5 began as the F-5-21 – this had uprated J85-GE-21 engines as well as a stretched fuselage and leading edge extensions for the wings. The new engines were tested on a refitted F-5B, and the first true F-5E (as the F-5-21 had been officially designated) flew in August 1972. There was also an equivalent two-seater version, the F-5F. Unlike the F-5B, which accommodated a second pilot by rearranging the systems on a standard length airframe, the F-5F had a stretched forward fuselage, allowing the retention of a single cannon, although the ammunition supply was halved.

The Tiger II became standard equipment for the USAF's aggressor squadrons, teaching front line fighter pilots how to deal with dissimilar aircraft and Soviet-style tactics. The USAF F-5Es were finally withdrawn in 1990, but former Swiss F-5Ns still fly as adversary aircraft with the Navy.

Malaysia was the first customer for the RF-5E Tigereye tactical reconnaissance version; this was much more capable than the earlier RF-5As, having a stretched nose with much greater volume. Saudi Arabia was the largest customer for new-build Tigereyes, operating ten examples in addition to a few earlier aircraft refitted with the new nose.

The Swiss Luftwaffe bought an initial batch of 72 F-5E/Fs in 1975, with most of these being assembled locally; a follow-on order for 38 aircraft was placed in 1981. Gradually replaced in frontline service as Swiss F/A-18s arrived, F-5s continued to fly in second line units as well as the Patrouille Swiss display team. Ironically, 32 former Swiss F-5s have "come home" being sold to the US Navy for use as aggressor aircraft.

Suggested Reading:

Model Airplane International December 2015 "F-5B...Training the Free World" Spencer Pollard "When Two Seats Are Better Than One..." Building the Kinetic 1/48 F-5 kit as a Canadian aircraft. SF-5M walk around feature

Andy Renshaw "Tiger at Sundown" The 1/48 F-5N from AFV Club as a VFC-111 aircraft Model Aircraft May 2016

Pierre Baudru "Viva España!" Model Aircraft May 2017 Building the 1/72 ESCI "Skoshi Tiger" kit as a Spanish F-5A

Robert D. Archer Edwards Air Force Base: Open House at the USAF Flight Test Center 1957-1966 p.130-131 four photos of the N-156F armed with AS.30 missiles