CLEARANCE: Above Top Secret
- Mar 11, 2006
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i have that book, but i don't remember seeing these illustrations, what edition are they from?, i have the one with the painting on the dust jacket.Jemiba said:Just two 3-views, the W.80 and the W.90 Goliath from
"Westland Aircraft since 1915" by Derek N.James, Putnam :
With Britain setting the pace in turbine engine production, it was natural that Westland should study the possible application of shaft-turbine power to helicopter design. One outcome of these studies was the twin-engined W-81 project of 1951. It was highly ambitious, with a payload of 32 fully-armed troops or four tons of cargo, loaded weight of 19,000 lb., estimated maximum cruising speed of 180 m.p.h. and maximum range of 950 nautical miles. Even the standard large helicopters if 1965 hardly exceed such a performance, but this is not the primary reason why the W-81 deserves to be remembered. So far as is known, it was the first helicopter design produced anywhere in the world in which the engines (Armstrong Siddeley Double Mamba) were mounted in the now-conventional position, above the cabin. Westland was, thus, the first company to realise that the comparatively small size and weight of turbine engines would enable them to be removed from inside the fuselage, giving much greater room for payload and facilitating loading and unloading, as well as reducing the complexity and weight of the transmission system.
The W-81 came to nothing because there was no current requirement for such a large machine. So Westland began examining the possibility of adapting standard Sikorsky airframes to turbine power.
NOTE: Bold type is mine.In addition to the effort expended in Anglicising and developing the Sikorsky designs and selecting British equivalents for the original U.S. materials on the Dragonfly and Whirlwind helicopters, the Westland design office initiated a number of interesting original helicopter projects of its own.
Three such projects, undertaken in the early nineteen-fifties, were the W-80, W-85 and W-90.
The W-80 was a 36-seat, 24,500 lb. machine intended for inter-city work. Drawings prepared at the time show a machine of relatively fine lines, powered by two Bristol Hercules engines, mounted in outboard nacelles. The driveshafts from the engines were mounted at right-angles to the line of flight and inclined in a vertical plane towards the main gearbox above the cabin roof. Considerable development work was undertaken on the design of the gearbox units required for this type of twin-engined drive to a single rotor.
The W-85 was a projected 100-seat military helicopter powered by six Armstrong Siddeley Adder turbojet engines mounted in pairs on each blade-tip. The machine had nose-loading doors, with a small passenger-sized ventral exit at the rear. The crew compartment was located high in the fuselage, above the nose doors. With a rotor diameter of 104 ft., this machine had an all-up weight in the 60,000 lb. class.
Most impressive project of all was the W-90. This design for a 450-seat military helicopter was powered by three large Armstrong Siddeley turbojet engines mounted one on each blade of the 196 ft. diameter main rotor. It looked like a scaled-up version of W-80, with nose-loading doors and a ventral entrance. The troops were carried on three separate decks, the lower one of which could be used for the carriage of army vehicles or artillery. All-up weight of this huge machine was over 200,000 lb.
Projects for a number of Navy spotter helicopters were also undertaken during this period.