Australia’s Avon Sabre Trainer’

The Americans had encountered this problem some years before and their solution was almost complete. On 14th December, 1953, the prototype two-seat TF-86 flew for the first time. By coincidence, the following day details of the new aircraft were sent to CAC, in response to an earlier request.

The TF-86 project was initiated at North American Aviation in February, 1953. The prototype was a converted F-86F, a model similar to the F-86E. The nose intake, rear fuselage and empennage were left unchanged. The wing was equipped with a slatted leading edge to provide good low-speed handling characteristics for landing. The forward section was modified and extended by some 1. 6 metres (5ft 3in) to fit a second cockpit behind the first. The wing was moved forward 20cm (Bin), with the relocation of the rear spar resulting in a slight reduction in the fuel cell volume.

The forward cockpit was to be occupied by the student, with the instructor in the rear. A single ‘clamshell’ canopy covered both cockpits, replacing the single-seat sliding canopy. Both cockpits were fitted with all the normal F-86 instruments and controls, except for the gunsight was provided in the forward cockpit only. However, guns were not fitted; the extra room allowed the incorporation of a baggage compartment in the nose.

Surprisingly, performance was not degraded by the conversion; in fact, the two-seat machine had a faster rate of climb, higher service ceiling, lower stalling speed and similar maximum speed.

The first TF-86, 52-5016, crashed on only its ninth flight in March 1954, killing pilot J. Lynch. A second F-86F was converted to become the second TF-86 prototype (53-1228). This machine differed from the first by carrying the two 0. 50 in. machine gun armament and having provision for drop-tanks or practice bombs. Quantity production was planned, but the arrival of the F-100 Super Sabre changed everything. The prototype YF-100 had flown earlier in May 1953. This aeroplane was to give the USAF supersonic capability; in fact, the F-100 was the first turbojet production aircraft to exceed the speed of sound in level flight. Its forebear, the F-86, was to be virtually obsolete within a year. Two-seat versions of the F-100 were already planned and there seemed no future for the TF-86 and the concept was dropped. The second TF-86 was to be the last and ended its days as a chase plane at Edwards Air Base.

CAC’s first task was to evaluate the cost and feasibility of producing a two-seat Avon Sabre. It was estimated that the engineering task would take some 65,000 hours. The changes to the standard Avon-Sabre were to be virtually the same as those made to the F-86F. The North American drawings for the forward extension were to be purchased and little change was anticipated. The balance problems caused by the longer nose meant that the Aden cannons carried by the fighter version could not be fitted. (The Avon Sabre was fitted with two 30mm cannons in place of the six 0. 5in machine guns of the F-86. ) The Avon-Sabre Trainer would have weighed 14,360lbs (about 1,000lbs lighter than the fighter), giving it similar perform- ance advantages to the TF-86.

It is not known why the Trainer was not proceeded with; in any case, the Vampire Trainer did prove to be adequate and no real difficulties were encountered by the RAAF in converting pilots onto the Avon-Sabre. The Trainer moved from the drawing board to the filing cabinet.