Close Cousins: IAI Lavi versus F-16 Viper

Some experts feel that the performance of the IAI Lavi would be broadly comparable to today’s F-16C/D Viper in most departments and superior in some.

IAI’s Lavi (Young Lion) fighter bomber successfully completed its maiden flight at the end of December 1986. Only three complete prototypes were built before the Israeli Government voted to discontinue development due to concerns over costs. Nevertheless, the project illustrated the advanced capabilities of IAI, and many of the aircraft’s components went on to be made commercially available. Furthermore, much of the technical knowhow accumulated during the development of the Lavi contributed to the achievement of Israel’s first launch of a satellite into space in 1988.

As told by Bertie Simmonds in his book F-16 Fighting Falcon, it’s always going to be the way that the Lavi was compared to the F-16 as there were some similar design traits. In essence though, the Lavi was smaller and lighter than the General Dynamics F-16, with initially a less powerful powerplant, meaning the resultant thrust-to-weight ratio was slightly lower. Unlike the F-16 with its traditional tail section, the Lavi’s configuration was that of a tailless canard delta, although the wing was unusual in having shallow sweep on the trailing edge. The wingtips — like that of the F-16 — were fitted with missile rails to aid combat persistence.

The wing area was 38.50 square metres, 38% greater than the wing area of the F-16, giving an almost exactly proportionally lower wing loading, while the control system was relaxed static stability and quadruplex fly-by-wire (FBW), with no mechanical backup. The Lavi was a very unstable aircraft – even compared to an F-16 – so like the Viper the computers were what kept the Lavi in the air.

One very similar design feature was the engine intake, which was a plain chin type scoop, similar to that of the F-16, which was known to be satisfactory at high angles of attack. The sharply swept vertical tail, effective at high angles of attack due to interaction with the vortices shed by the canards, was mounted on a spine on top of the rear fuselage, and supplemented by the two steeply canted ventral strakes, mounted on the ends of the wing root fillets.

Normally jet fighters are designed as single-seaters first and then a two-seater – with the second seat taking away either avionics or fuel. IAI designed the two-holer first, allowing the spare room to allow for any future avionics fit – they did after all use the ‘camel hump’ models of the McDonnell Douglas A-4. IAI learned lessons well. Internal fuel capacity was 3330 litres around 16% less than the F-16 although figures show that this was offset by the Lavi’s lower drag and the better fuel consumption of the PW1120 (the Pratt & Whitney PW-1120, a development of the F-100 which was in service with both the F-15 Eagle and the original F-16A and B Fighting Falcons).

Like the F-16 the Lavi had a blown, wraparound bubble canopy. The cockpit itself dispensed with the F-16’s sidestick controller, as IAI wanted a more traditional, centrally mounted one. It’s thought that feedback from pilots in combat led to a worry about what would happen to a Lavi or F-16 pilot if their right arm or hand was injured. With a right-hand-side sidestick controller fitted, the left hand could not easily take control and fly the aircraft hack to base.

A sidestick controller also meant less console space on the right-hand console. The Lavi also had an upright seat, rather than the raked F-16’s ejection seat, due to Israeli Air Force (IAF) pilots often complaining of neck strain while scanning the sky in an F-16. Otherwise the Lavi cockpit was of the time benefitting from HOTAS or ‘hands on throttle and stick’ controls, a Hughes wide-angle HUD or head-up-display and colour and black and white head-down displays.

In the nose of the Lavi would be the Elta EL/M-2035 multi -mode pulse Doppler radar. Developed from that in the Kfir-C2, it was an advanced set for the day, which could track several targets at once with boresight, look-up and track while scan modes. It had two air-to-ground modes and ground mapping and terrain avoidance. Also as part of a standard fit was the Elta/Elistra Electronic Warning System which could work in both passive and active modes. Carried internally, this could be backed up with podded electronic counter measure pods and jammers.

The weapons to be carried on the Lavi were standard for the IAF of the time. As well as underwing fuel tanks, the internal cannon was from the trusted DEFA company of 30mm calibre, capable of up to 1500 rounds per minute and housed in the right wing-root. Israeli pilots had come to trust the DEFA cannons from the Dassault Mystere of the 1950s, through to the Mirage and even had them fitted on American A-4 Skyhawks rather than the 20mm Colt Mk.12s. Air-to-air armament was to be the Rafael Python 3 infrared homing short-range dogfight missile. Air-to-ground weapons would include the dumb Mk.80- series freefall bombs, the Hughes AGM-65 Maverick family of missiles, the IAI Gabriel anti-ship missile and the IAI Popeye air-to-ground missile.

Some experts feel that the performance of the IAI Lavi would be broadly comparable to today’s F-16C/D in most departments and superior in some. Like the canard foreplanes fitted to the likes of the Eurnfighter Typhoon and the SAAB Gripen, control authority of unstable aircraft is better than that of a conventional tailed machine, meaning that the Lavi would supposedly be quicker into a turn than an F-16. Those that flew the Lavi heaped praise on its agility and power.

Today the Lavi is almost a memory. Prototypes B-01, 04 and 05 were sold for scrap. B-02 is on display at the IAF Museum in Hatzerim. B-03 was flying into the 1990s as a demonstrator in support of IAI’s advanced fighter aircraft and cockpit technology programmes. There were also rumours that one aircraft was delivered to South Africa in the early 1990s or that design cues were used on the Chinese Chengdu J-10 after technology was sold by Israel to China. This has been denied by both countries.

F-16 Fighting Falcon is published by Mortons Books and is available to order here.

Photo credit: Israeli Air Force photographer and U.S. Air Force photo by Master Sgt. Lee Osberry