Westland Westminster

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Westminster
Type	Heavy-lift helicopter
Manufacturer	Westland Aircraft
Maiden flight	15 June 1958
Status	Cancelled project
Number built	2

The Westland Westminster was a British helicopter of the 1950s. It was powered by two turboshaft engines driving a single, five-bladed rotor. Initially unclad, the all-metal airframe was later enclosed in a Terylene covering.

1 Development
2 Specifications (Westminster)
3 References
4 External links
5 Related content

[edit] Development

The Westminster was the first tangible result of efforts that Westland had been making throughout the 1950s to produce a gas-turbine-powered heavy-lift helicopter. Projects ranged up to the remarkable W.90, a 450-seat troopship with three Sapphire turbojets mounted on its rotor-tips.^[1]

In 1954, Westland investigated licenced manufacture of the Sikorsky S-56 for the civil market with turboshaft power. The company sought Ministry of Supply support for the proposal but this was not forthcoming. In June 1958, Westland obtained an extension to their licence agreement with Sikorsky to cover the main-rotor, gearbox, tail-rotor, transmission and control systems of the S-56. Faced with continuing government indifference, Westland decided to press ahead with a private-venture design for a heavy-lift transport, built around the S-56 systems but powered by a pair of Napier Eland turboshafts. At the time, Westland was heavily committed to development of the Wessex and the Westminster project had to be run on a shoestring.^[1]

Two variants were initially envisioned: a 40-seat, short-range civil transport and a flying crane with a 15,000 lb capacity. In March 1956, Westland decided to build the first prototype as a flying test rig with a tubular steel space frame in place of the main fuselage; cockpit power-train and undercarriage attached to this. With economy a priority, off-the-shelf components were used as far as possible, with donors such as the Westland Whirlwind helicopter and the Bristol Freighter aeroplane. This prototype was completed in February 1958; after the usual static and systems testing, engine runs and nearly 20 hours of "tied-down" engine testing, the first flight took place on 15 June. Flight testing showed up significant vibration. As a result, a number of changes in the design of the second prototype, including replacement of the main-rotor with the six-blade unit from the Sikorsky S-64. Once the statutory ten hours had been flown, this first Westminster was registered G-APLE and work started on constructing the second prototype.

Around this time, the Admiralty began to feel that the Westminster project was delaying development of the Wessex. Although this was mere fancy, it bided ill for the larger aircraft.^[1]. For the moment, work continued; G-APLE's space frame was covered with a streamlined shell of wood covered with Terylene fabric and the rotor was replaced with an experimental six-blade unit.

The second prototype flew on 4 September 1959, being registered G-APTX, and flight testing continued but the British helicopter industry was in a state of flux; the entire industry was being consolidted under Westland with the company's purchase of the helicopter divisions of Saunders-Roe, Bristol and Fairey. In the process, Westland acquired two potential rivals to the Westminster: the Bristol 194 and Fairey Rotodyne (a gyrodyne). Rationalisation was necessary and since the Rotodyne was a more advanced concept, work on the Westminster ceased in September 1960.

The two aircraft were broken up; the components supplied by Sikorsky were stripped out and shipped back to the USA to avoid paying import duty and the airframes were sold as scrap^[1].

[edit] Specifications (Westminster)

Data from Westland Aircraft since 1915^[1]

General characteristics

Crew: 2 (+2 observers projected)
Capacity: (Projected: 40 passengers
Length: (27.4 m ^[2])
Rotor diameter: 72 ft (21.95 m<refname="Avia"/>)
Height: 21 ft 1 in ()
Disc area: 4,069 ft² ()
Max takeoff weight: 14,965 kg^[2] ()
Powerplant: 2× Napier Eland E220 turboshaft, 2,920 hp () each

Performance

Maximum speed: 135 knots (155 mph)
Cruise speed: 100 knots (estimate for production machines: 130 knots) (115 mph)
Range: (estimate for production machines) 104 nm (120 mi)
Rate of climb: 1,750 ft/min (estimate for production machines: 2,000 ft/min ()