Avro C-102 Jetliner
The Canadian branch of the Avro company and the Canadian Government together produced what was one of the first airliner designed specifically for turbojets. The Jetliner was designed to meet a Trans-Canada Air Lines requirement. It was the first jet transport to fly in North America and the second to fly in the world, on August 10, 1949, 13 days after the flight of the de Havilland 106 Comet. The Canadian C-102 Jetliner was the second to carry revenue payload (mail). The Avro Jetliner was years ahead of the Boeing 707, and the Jetliner did not have the problems of the Comet.
The C-102 had been designed to the Trans Canada Airline requirment agreed in 1946, which called for a 36 seat aircraft with a cruising speed of 425 miles per hour, a "still-air" range of 1,200 miles, an average distance between stops of 250 miles, with 500 miles as the longest let requiement. The 40-seater Avro C.102 T.C.A. was a medium-range four-jet transport in advance of any other in the world. This aircraft was expected to cruise at 430 m.p.h. at 35,000 ft on the power of four Rolls-Royce Derwents (4 by 3,500lb thrust). The span is 98 ft and the weight 52,500 lb. By virtue of its good, relatively uncongested airports, wide choice of stage length and accurately predictable weather, Canada could have been the first country to introduce pure-jet transport to regular to airline service.
The C-102 Jetliner was the world's first pure-jet transport aircraft intended specifically for short/medium-range operation. The power units are four Rolls-Royce Derwent V centrifugal-flow turbojets and the normal range with 50 passengers and baggage, and allowing for taxying and takeoff, stacking, fuel for diversion to an alternate airfield, instrument approach, etc., was approximately 500 miles. Notwithstanding its exceptionally high speed, the Jetliner has been designed to operate from runways of 4,000-5,000ft length, under I.C.A.N. conditions.
This unique 50-passenger machine was designed for a maximum cruising speed of 427 m.p.h. at 30,000-35,000ft. Of circular cross-section, the fuselage measures 10ft in diameter and comprises four main components - nose, center-section (including the center wing), rear centersection, and rear section (including the lower fin). In order to achieve the highest strength in the former rings, the stringers are external to the outside former-flanges, thus avoiding the need for cut-outs. The forward pressure bulkhead is immediately ahead of the main instrument panel and isolates the nosewheel compartment from the pressurized region; the rear pressure-bulkhead is clamped between the angles of the after transport-joint. There were four escape-hatches in the cabin and one in the flight deck.
The windscreen structure is an aluminium-alloy casting, with three center panels of special sandwich construction, incorporating electrical de-icing; a vinyl interlaver ensures retention of pressure in the cabin in the event of windscreen damage. The two direct-vision windows and two after windows are of Plexiglass. Pressure-sealed entrance doors are located in the port fuselage-side at each end of the main cabin, and an additional door can be provided on the starboard side for the rear baggage compartment.
The mainplane is built in three sections and has detachable tips. Conventional two-spar construction, with heavy-gauge skin, is used for the center-section, which carries the four turbojets. In the outer wings, which are attached to the centre-section by continuous butt-strap joints, the two-spar arrangement is retained, but heavygauge skin and stringers take the place of concentrated spar booms to provide the high torsional stiffness necessary for the speeds attainable. Between the spars of the inner portions of the outer wing are the four integral fuel-tanks. The ailerons, which extend over more than half the outer wing span, are unbalanced aerodynamically and power assisted hydraulically in the ratio of 5:1. Piano hinges on the upper surface allow complete sealing and internal massbalancing and a manual trimmer are incorporated. Split flaps, hydraulically operated, extend from the outer wing roots to the ailerons, and additional split-type dive brakes are fitted on the center-wing and the aft section of the nacelle. Those on the centre wing can also be used as landing flaps.
The empennage consists of an upper and lower fin section with a high-set tailplane, double rudder and double elevator surfaces. The rear surface of the elevator is operated manually, but power operation is provided for the forward auxiliary surface. Electrical trimmers, which can be manually operated if desired, are fitted. Of the two unbalanced rudder surfaces, the rearmost is manually operated and, as in the case of the elevator, the forward auxiliary surface has power operation. Normally the manual surface only is required, the auxiliary surface being brought into play in the event of engine failure at low speeds.
Main and nose units of the undercarriage have twin wheels; all wheels retract forwards, the main wheels, when raised, lying between the jet pipes. Retraction time is approximately 8 sec. The nosewheel shock-absorber unit is ot the Dowty liquid-spring lever-suspension type, and each main undercarriage unit consists of a telescopic leg. likewise utilizing liquid springing. Undercarriage operation and nosewheel steering are electro-hydraulic.
The four Derwent 5 turbojets are mounted in pairs in two underslung nacelles. Welded chromium-molybdenum steel tubing is used for the mountings, and accessories are grouped in each nacelle on gear box located between the turbojets and attached to the front spar. The upper half of the cowling is a permanent structure, provided with small doors for slinging and a larger door to permit access to the upper part of the accessory gear box; the lower half consists of two large doors swinging to the sides of the nacelle and one door swinging to the rear. By uncoupling the jet pipe, drive shaft, connectors, and detaching the unit from the mounting and lowering it directly on to an engine trolley, a Derwent can be replaced in a very short time.
By June 1951 more than 100 hours' test-flying had been completed. Level speeds of more than 500 m.p.h. had been attained during the year, and the cruising speed has been established as 450 m.p.h. A height of 39,500ft - 9,500ft higher than the normal cruising height - had been attained. Many three-engined take-offs had been made at various speeds and at maximum gross weight. On a number of occasions the aircraft has been flown, with only one of its four Rolls-Royce Derwents operating, at about 200 mph, with no loss of height observed. Several test flights were made over a triangular course of about 800 miles, and the average time was about two hours. These flights were made at normal cruising height and showed that about 1,600 Imperial gallons of fuel had been used.
Although somewhat short in range, the design's great potential was never realized. Avro encountered difficulty in dealing with TCA and the Department of Transport and, despite considerable interest from Howard Hughes, owner of TransWorld Airlines, and the United States Air Force (USAF), no Jetliners were sold. With the outbreak of the Korean War Howe ordered work on the project discontinued so that Avro could concentrate on military aircraft. Further development was stopped by the federal government in 1951 in order to force the company to concentrate on the CF-100 jet fighter. Only one Jetliner was built.
The Jetliner never did go into comercial use, as orders were never placed, construction on the partially built second prototype was abandoned. On 10 December 1956 the Jetliner was ordered destroyed, and after contacting the National Aviation Museum turned up no interest in obtaining the aircraft due to a lack of space, the Jetliner was cut up on the 13th of December 1956 with only the cockpit section surviving (in the Canadian Aviation Museum in Ottawa).
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