By the end of the 1970s, the Kheil HaAvir's Fouga CM.170 Magister jet trainers were beginning to reveal structural fatigue - with cracks appearing in the wings and fuselage. Israeli Aircraft Industries embarked upon a thorough rebuild programme resulting in the IAI Tzukit (Thrush) trainer. The first Tzukit was handed over to the air force in May 1981, with serial re-deliveries running 1983-1986. This was to be an interim programme, filling a gap until the arrival of a new Advanced Jet Trainer (AJT). [1]
With the IAI trainer group absorbed by the AJT project, the Tzukit Life-Extension Group turned to alternative roles for the aged Fougas airframes. Since the cramped Tzukit airframe could not accommodate ejection seats, it was perhaps inevitable that unmanned variants began to dominate. First were simple, remotely-controlled target aircraft. However, the IAF was satisfied with its US-supplied Firebee target drones.
The next development - with what would now be called a 'pilot optional' aircraft - began with a prototype Tzukit with an enormous satellite uplink antenna fitted above its former rear cockpit. This aircraft demonstrated the potential for RPVs with pre-programmed flightpaths adjusted by satellite commands while airborne. The success of this demonstration led to yet another Fouga rebuild programme - that of the IAI Yanshuf (Owl) UAVs. This aircraft had their cockpits entirely removed. The satlink antenna was moved forward - the former rear cockpit area now housing a retractable electro-optical turret by Elron/Elbit.
Yanshuf-M - The Maritime Patrol Owl
IAI also saw a potential market for an extended-range reconnaissance UAV capable of filling the Maritime Patrol role. To that end, the basic Tzukit/Yanshuf conversion was updated an redesigned. The most obvious change was substituting a comparatively large IAI SAR surface search radar antenna under the belly (with a smaller Elbit E/O turret place forward under the nose). To accommodate the bulging SAR radome, the stumpy Fouga undercarriage had to be completely redesigned to provide adequate clearance. Extensively tested by the Israeli Defence Forces, this revised Yanshuf-M variant was judged a success. However, IDF orders were not forthcoming and no foreign interest was expressed. With that, the Yanshuf-M project was quietly dropped and IAI moved on to original MALE UAV designs.
_____________________________________
[1] For this Advanced Jet Trainer project, IAI joined forces with an American firm - Aviation Technology Group Inc - in an attempt to produce a completely new, twin-engined, jet trainer. However, this ambitious programme faltered and no Javelin AJT was ever completed.