Westland WS-51 Dragonfly

Westland Aircraft

Company type	Company
Industry	Aerospace
Headquarters	Yeovil , United Kingdom
Products	Helicopters, including Westland WS-51 Dragonfly

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The Westland WS-51 Dragonfly was a helicopter produced by Westland Aircraft as a British-licensed adaptation of the American Sikorsky S-51 model.

Design and development

An agreement was finalized on 19 January 1947 between Westland Aircraft and Sikorsky permitting the manufacture of a British version of the S-51 under licence. This version was equipped with a 500 hp Alvis Leonides radial engine. Westland also created a modified variant known as the Westland Widgeon, which ultimately did not achieve commercial success.

Development experienced delays due to the necessity of adapting American blueprints to incorporate British components and substituting the original engine with the domestically produced Alvis Leonides 50. The prototype, bearing registration G-AKTW, completed its maiden flight at Yeovil on 5 October 1948, piloted by Alan Bristow, only sixteen months after construction commenced.

Following evaluation, initial procurement orders were placed for the UK armed forces, consisting of thirteen Dragonfly HR.1s for the Royal Navy and three Dragonfly HC.2s for the Royal Air Force.

Operational history

A fleet of seventy-two Dragonfly helicopters served within the Fleet Air Arm of the Royal Navy, fulfilling roles including training, air-sea rescue, and communications. The first squadron to receive these helicopters was 705 Naval Air Squadron, recognized as likely the earliest all-helicopter squadron established outside the United States. The Dragonfly holds distinction as the first helicopter constructed in Britain to be adopted by the navy and to operate from a British vessel during trials aboard RFA Fort Duquesne in 1951.

In 1953, a Dragonfly led the helicopter formation during the flypast at the Coronation Review of the Fleet.

Plans to upgrade naval Dragonflies to the Widgeon configuration featuring an expanded cabin—designated as Dragonfly HR.7—were abandoned in 1957 due to reductions in defence spending. The type was succeeded by the Westland Whirlwind, another Sikorsky derivative, during the late 1950s. Dragonflies were deployed in humanitarian relief efforts following the North Sea flood of 1953 and several units were utilized by the Royal Air Force for casualty evacuation missions amid the Malayan Emergency.

A total of fifty-one civilian WS-51 units were manufactured. These were employed by Pest Control Ltd for agricultural spraying, while others served as executive transport for organisations such as Silver City Airways, Evening Standard Newspapers, and Fairey Aviation. Exported examples operated in countries including Japan, Belgian Congo, Mexico, and Norway.

Variants

Westland/Sikorsky WS-51

Initial prototype model.

Dragonfly HR.1

A Royal Navy helicopter designed for air-sea search and rescue missions, equipped with a 540 hp Alvis 50 radial piston engine. A total of 13 units were produced, with some later upgraded to HR.5 standards.

Dragonfly HC.2

Designed for casualty evacuation by the Royal Air Force, this variant closely resembles the commercial Mark 1A. Two were built, and an additional unit was converted from a civilian Mark 1A.

Dragonfly HR.3

An air-sea search and rescue helicopter serving the Royal Navy, similar to the HR.1 but featuring all-metal rotor blades. Seventy-one units were manufactured, with some subsequently converted to HR.5 configuration.

Dragonfly HC.4

A casualty evacuation helicopter variant for the RAF, comparable to the HR.3 with all-metal rotor blades, with a production total of twelve aircraft.

Dragonfly HR.5

Royal Navy air-sea search and rescue helicopter fitted with an Alvis Leonides 23/1 engine and modernized instrumentation and avionics. Twenty-five units were upgraded from earlier HR.1 and HR.3 models.

Westland-Sikorsky WS-51 Mk.1A

Civilian transport helicopter powered by a 520 hp (388 kW) Alvis Leonides 521/1 radial piston engine, with 36 produced.

Westland-Sikorsky WS-51 Mk.1B

Civil transport version equipped with a 450 hp (336 kW) Pratt & Whitney R-985 Wasp Junior B4 radial piston engine, totaling 15 built.

H.1

WS-51 designation used by the Royal Thai Armed Forces (Thai: ฮ.๑).

Military and government users

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• Royal Ceylon Air Force - operated two Mk 1As.

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• Egyptian Air Force - received two Mk 1Bs.

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• Royal Iraqi Air Force - acquired three helicopters in 1951.

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• Italian Air Force - operated two Mk 1As.

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File:Westland-Sikorsky WS-51.jpg

Japan Maritime Self Defence Force S-51

• Japan Maritime Self Defence Force - three Mk 1As designated as S-51s were in service.

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• Royal Thai Air Force - utilized three Mk 1As known as Type 1 helicopters.

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File:BEA Sikorsky S-51 in 1953.jpg

British European Airways Sikorsky S-51 in 1953

• Royal Air Force - operated a total of fifteen HC.2 and HC.4 variants, including units assigned to Far East CASEVAC Flight RAF and No. 194 Squadron RAF.
• Royal Navy - multiple squadrons employed these helicopters, including Britannia Royal Naval College, and Naval Air Squadrons numbered 700, 701, 705, 727, 728, 744, and 771.

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• SFR Yugoslav Air Force - fleet included ten Mk 1Bs helicopters.

Civil operators

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• Sabena

• Record TV

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• Tohoku Electric Power

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• British European Airways
• Silver City Airways
• Fleet Requirements Unit, a civilian-managed unit operated by Airwork Ltd on behalf of the Fleet Air Arm

Surviving aircraft

File:WestlandDragonflyInBangkok.jpg

WS-51 Mk.1A displayed at the Royal Thai Air Force Museum, December 2014

Australia

• WG725 – HR.3 currently undergoing restoration at the Fleet Air Arm Museum located in Nowra, New South Wales.

Brazil

• PT-HAL (formerly G-AMHB) – Civil WS-51 helicopter utilized by the Record TV network and involved in the rescue during the Andraus building fire, exhibited at the Museu Eduardo André Matarazzo in Bebedouro, São Paulo.

Japan

• JA7014 "Kitakami" – Used by Tohoku Electric Power, preserved at the Misawa Aviation & Science Museum in Misawa, Aomori.

Malta

• VZ962 – HR.1 undergoing restoration at the Malta Aviation Museum situated in Ta'Qali, Attard.

Netherlands

File:Westland Dragonfly at Lelystad Flugsimulatorwochenende 20091107 129.jpg

HR.5 exhibited statically at the Aviodrome in Lelystad, Netherlands.

• WG752 – HR.5 displayed permanently at the Aviodrome museum in Lelystad, Flevoland.

Serbia

• 11503 – Mk.1B preserved on static display at the Aeronautical Museum Belgrade located in Surčin, Belgrade.

Sri Lanka

• CH501 – Mk.1A on permanent static display at the Sri Lanka Air Force Museum in Ratmalana, Western Province.

Thailand

• H1-4/96 – Mk.1A exhibited statically at the Royal Thai Air Force Museum in Don Mueang, Bangkok.

United Kingdom

File:Westland Dragonfly HR1 VX595 (6859029049).jpg

HR.1 displayed at the Fleet Air Arm Museum in Yeovilton, England.

• VX595 – HR.5 presented on static display at the Fleet Air Arm Museum in Yeovil, Somerset.
• WG719 – HR.5 shown statically at The Helicopter Museum located in Weston-super-Mare, Somerset.
• WG724 – HR.5 displayed statically at the North East Land, Sea and Air Museums situated in Sunderland, Tyne and Wear.
• WG751 – HR.5 preserved for static exhibition at the Chatham Historic Dockyard in Chatham, Kent.
• WH991 – HR.5 available for viewing on static display at the Yorkshire Air Museum located in Elvington, York.
• WN493 – HR.5 exhibited statically at the Fleet Air Arm Museum in Yeovilton, Somerset.
• WN499 – HR.5 currently undergoing restoration at the South Yorkshire Aircraft Museum based in Doncaster, South Yorkshire.
• WP495 – HR.5 presented for static exhibition at Morayvia in Kinloss, Moray.

Venezuela

• HR.3 displayed statically at the Museo Aeronáutico de Maracay located in Maracay, Aragua.

Specifications (WS-51 Mk.1A)

File:Westland WS-51 Dragonfly orthographical image.svg

Westland Dragonfly HR3

External links

• Westland Dragonfly profile on helis.com
• Photographic documentation of a Westland Dragonfly restoration. Archived 19 April 2023 at the Wayback Machine