The IAI Kfir (hebrew: כפיר) is an Israeli-built military aircraft based on the French Mirage 5. Following a French government embargo that prevented Dassault selling Israel the Mirages that they had already paid for, IAI produced an unlicenced copy of this aircraft as the IAI Nesher (possibly with the clandestine support of Dassault - see the article on the Nesher for details of these claims).

At the same time, IAI was planning a variant in which the Atar engine was to be replaced with an Israeli-built General Electric J79 engine, the same engine used on the American F-104 Starfighter and F-4 Phantom II fighters. The J79 provided a dry thrust of 49 kN (11,100 lb) and an afterburning thrust of 83.4 kN (18,750 lb).

The J79 was first fitted to a French-built Mirage III, flying in October 1970. This test aircraft was followed by an improved prototype in June 1973, with the name Raam ("Thunderbolt"). Apparently a number of Mirage III-based J79-powered aircraft were built by IAI under the name Barak ("Lightning") and participated in the 1973 Yom Kippur War, but really making the most of the new engine meant airframe changes.

Production deliveries of an optimized J79-powered Mirage derivative, under the name Kfir-C1 ("Lion Cub"), began in April 1975. The Kfir-C1 superficially resembled a Mirage 5, except for a distinctive "ram" air inlet at the front base of the tail to provide added cooling required by the J79 engine.

Only 27 Kfir-C1 fighters were delivered, to be replaced by the improved Kfir-C2. The Kfir-C2 had a number of enhancements to traditional Mirage aerodynamics. It featured narrow "strakes" along the tip of the nose; fixed but detachable canards; and an extended "dogtooth" outer wing. The aerodynamic improvements gave the Kfir better combat manoeuvrability, reduced landing and take-off distance, and improved low-speed handling.

All but two of the Kfir-C1s were upgraded to the Kfir-C2 configuration. 185 Kfir-C2s were built, including a number of Kfir-TC2 two-seat trainers. The trainer versions are very unusual looking, as they have an extended nose containing avionics displaced by the second seat, and the nose is noticeably drooped to give a reasonable cockpit view. The result is a somewhat comical "big nose" appearance. Final production Kfirs, delivered starting in the mid 1980s, featured nine stores pylons, upgraded avionics, a more powerful engine (J79-GE-J1E) and other refinements, and were designated Kfir-C7 and Kfir-TC7.

Ten refurbished Heyl Ha'Avir C2 fighters and two TC2 trainers were supplied to Ecuador in 1983, 13 Kfir-C7s and two TC7 trainers were provided to Colombia in 1987, and 25 of the upgraded Kfir-C1s were leased to the U.S. Navy and the U.S. Marine Corps to act as F-21A aggressor aircraft for "Red Flag" training.

In 1991, IAI introduced an upgraded Kfir-C2, known as the Nammer ("Tiger"), for the export market. This aircraft had a slightly stretched fuselage; modern avionics, including multifunction displays and "hands on throttle and stick (HOTAS)", controls, and the ability to accommodate either a SNECMA Atar 9K-50 turbojet or a GE/Volvo F404 / RM12 turbofan. Apparently the use of the J79 engine led to American export restrictions on the type that the chafed on the Israelis, so they went to a different engine fit.

Along with the usual twin 30 millimetre cannon, the Nammer had nine stores pylons and could carry up to 6.25 tonnes (13,800 pounds) of external stores. It also had provision for in-flight refuelling. Although it seems there were no takers for the Nammer, the aviation press has mentioned that IAI is promoting a Kfir 2000 upgrade, though details are unclear. In any case, as with the Mirage III/5/50 itself, there is still life left in the Kfir.

Trivia

• The Kfir was featured in the movie Iron Eagle, acting in place of MiG-23 fighters.