- Westland Dragonfly
Infobox Aircraft
name= WS-51 Dragonfly
caption=Dragonfly HR5
type=rescue or communicationshelicopter
manufacturer=Westland
designer=
first flight=
introduced= 1950
retired=
status=
primary user=Royal Navy
more users=Royal Air Force
produced= 1950-
number built= 133
unit cost=
developed from =Sikorsky H-5
variants with their own articles = Westland WidgeonThe Westland WS-51 Dragonfly helicopter was built by Westland and was a license-built version of the American Sikorsky S-51. Apart from military use, it was sold into civilian use. A development, the Widgeon did not make it into equally large scale production.
Design and development
In December 1946 an agreement was signed between Westland and Sikorsky to allow an Anglicized version of the S-51 to be manufactured under license in Britain. These would be powered by the 500 hp
Alvis Leonides radial engine. A modified version was also developed by Westland as the Westland Widgeon.Operational history
The Dragonfly entered service with the
Royal Navy in 1950 in the air-sea rescue role. A number were also used by the Royal Air Force for casualty evacuation. It was replaced by the Westland Whirlwind, another derivative of a Sikorsky design, in British service in the late 1950s. fifty-one of the civilan version were produced.Variants
;Dragonfly HR.1:Air-sea search and rescue helicopter for the Royal Navy powered by a 540 hp (403 kW) Alvis 50 radial piston engine. 13 built, some modified later as HR.5s.;Dragonfly HC.2:Casualty evacuation helicopter for the
Royal Air Force similar to the commercial Mark 1A, three built.;Dragonfly HR.3:Air-sea search and rescue helicopter for the Royal Navy. Similar to the Dragonfly HR.1, but fitted with all-metal rotor blades, 58 built some later modifed as HR.5s.;Dragonfly HC.4:Casualty evacuation helicopter for the RAF similar to the Dragonfly HR.3 with all-metal rotor blades, 12 built.;Dragonfly HR.5:Air-sea search and rescue helicopter for the Royal Navy similar to the Dragonfly HR.3. Modifed from HR.1 and HR.3.;Westland-Sikorsky WS-51 Mk 1A:Civil transport helicopter powered by a 520 hp (388 kW)Alvis Leonides 521/1 radial piston engine. Built by Westland in the United Kingdom.;Westland-Sikorsky WS-51 Mk 1B:Civil transport helicopter powered by a 450 hp (336 kW)Pratt & Whitney R-985 -134 Wasp Junior radial piston engine.;Westland/Sikorsky WS-51:Prototype.Operators
;BEL
*Sabena - Three helicopters;flag|Egypt|1952
*Royal Egyptian Air Force - Two helicopters as VIP transports.;FRA
*French Air Force - Nine helicopters initially for use inIndo-China .;flag|Iraq|1924
*Royal Iraqi Air Force - Two helicopters;ITA
*Italian Air Force - Three helicopters;flagicon|Sri LankaCeylon
*Royal Ceylon Air Force - Two helicopters;JPN
*Japan Air Self Defence Force - Three helicopters
** 153rd Rescue Squadron
* Tohuku Electrics - Two helicopters for power line inspection.;THA
*Royal Thai Air Force - Four helicopters;UK
*Empire Test Pilot's School
*Royal Air Force
** Central Flying School
**No. 194 Squadron RAF
*Fleet Air Arm
**No. 705 Squadron FAA
**No. 771 Squadron FAA ;YUG
*SFR Yugoslav Air Force - Ten helicoptersurvivors
* Dragonfly HR3 "WG751" on display at the
Chatham Historic Dockyard , Chatham, United Kingdom.
* Dragonfly HR5 "WN403" on display at theFleet Air Arm Museum atRNAS Yeovilton inSomerset ,United Kingdom
* Dragonfly HR3 "G-AJOV" on display at theRoyal Air Force Museum atRAF Cosford , Shropshire, United Kingdom
* WS-51 Mk 1B "11503" on display at theYugoslav Aeronautical Museum atNikola Tesla Airport ,Belgrade ,Serbia .pecifications (Dragonfly HR1)
aerospecs
ref= [Orbis 1985, page 3080]
met or eng?= engcrew=1 (pilot)
capacity=3 (passengers)
length m=17.54
length ft=57
length in=6½
span m=
span ft=
span in=
swept m=
swept ft=
swept in=
rot number=
rot dia m= 14.63
rot dia ft= 48
rot dia in= 0
dia m=
dia ft=
dia in=
width m=
width ft=
width in=
height m=3.95
height ft=12
height in=11½
wing area sqm=
wing area sqft=
swept area sqm=
swept area sqft=
rot area sqm= 168.11
rot area sqft= 1809.56
volume m3=
volume ft3=
aspect ratio=
empty weight kg=1987
empty weight lb=4380
gross weight kg=2663
gross weight lb=5870
lift kg=
lift lb=eng1 number=1
eng1 type=Alvis Leonides 50 radial piston
eng1 kw= 403
eng1 hp= 540
eng1 kn=
eng1 lbf=
eng1 kn-ab=
eng1 lbf-ab=
eng2 number=
eng2 type=
eng2 kw=
eng2 hp=
eng2 kn=
eng2 lbf=
eng2 kn-ab=
eng2 lbf-ab=max speed kmh=153
max speed mph=95
max speed mach=
cruise speed kmh=
cruise speed mph=
range km=483
range miles=300
endurance h=
endurance min=
ceiling m=3780
ceiling ft=12,400
glide ratio=
climb rate ms=
climb rate ftmin=
sink rate ms=
sink rate ftmin=armament1=
armament2=
armament3=
armament4=
armament5=
armament6=ee also
aircontent
related=
*Sikorsky H-5
*Sikorsky R-4
* Westland Widgeonsimilar aircraft=
lists=
*List of helicopter models
see also=
*List of aircraft of the Royal Air Force
*List of aircraft of the Fleet Air Arm References
*cite book |last= |first= |authorlink= |coauthors= |title= The Illustrated Encyclopedia of Aircraft (Part Work 1982-1985)|year= |publisher= Orbis Publishing|location= |issn=|pages=
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