Back Westland "Wessex"

Westland "Wessex"

After acquiring a licence in 1956 to manufacture the Sikorsky S-58 helicopter, Westland imported one of these aircraft in HSS-1 configuration. Given the British serial number XL.722, this aircraft was test-flown for a time with its original 1525hp Wright R-1820-84 engine before being modified to accept a 1100shp Napier Gazelle NGa.11 gas turbine. In its new form it was flown for the first time on 17 May 1957, and was later joined by two pre-production Wessex HAS Mk.1's for Naval trials; the first of these flew on 20 June 1958. The HAS Mk.1 went into production in 1959 for the Royal Navy as a submarine search and strike helicopter equipped with dipping Asdic and provision for one or two homing torpedoes. Powered by a 1450shp Gazelle Mk.161 engine, it began service trials with No.700H Flight in April 1960 and has since been delivered to Nos. 706, 737, 771, 815, 819 and 848 Squadrons. The first of these to commission, in July 1961, was No.815; the Wessexes of No.848 Squadron were for commando assault duties aboard H.M.S. Albion, having the ASW gear removed to make room for 16 troops or 8 stretchers and a medical attendant in the main cabin. Alternatively, a slung load of 1814kg can be suspended from an under-fuselage hook. From January 1967 the Wessex Mk.1's have been joined in service by the HAS Mk.3, which is powered by a 1600shp Gazelle Mk.122, and has an extended rotor head fairing and large dorsal radome. Twenty-seven HAS Mk.31's supplied to Royal Australian Navy since August 1962 are similar to the HAS Mk.1 apart from their 1540shp Gazelle Mk.162 engines.

All other Wessex variants so far announced have two coupled Gnome engines in place of the single Gazelle. These include the RAF's HC Mk.2, flown for the first time in production form on 5 October 1962 and entering service with No.38 Group in February 1964; the Navy's HU Mk.5, for which two orders have been placed and which entered service in summer 1964 as a commando-carrier assault transport; twelve Mk.52's for the Iraqi Air Force, three Mk.53's for the Ghana Air Force, and one Mk.54 for the Brunei government. Seven Wessex Mk.60's have been built for Bristow Helicopters Ltd. These are 10-passenger commercial equivalents of the Mk.2 and operate in support of the oil and gas drilling rigs in the North Sea.

K.Munson "Helicopters And Other Rotorcraft Since 1907", 1968

Westland "Wessex"

In 1956, Westland, who held the license to build the Sikorsky S-55, acquired the license for the more modern S-58. The powerplant of the latter was considered unsatisfactory and the British firm began a partial redesigning of the American aircraft to enable a 1100shp Napier Gazelle NGa. 11 turbine to be installed instead of the original 1525hp Wright R-1820-84 radial. Thus transformed, one might have assumed that the helicopter was underpowered, but the nature of turbine engines is such that- it was in fact ideal. The slight loss of power was offset by greater reliability, a reduction in vibration and weight, easier maintenance and a lowering of specific fuel consumption.

The Royal Navy immediately ordered the new helicopter as the Wessex HAS Mk.1, to replace the older Whirlwind HAS Mk.7. The aircraft was basically similar to the Sikorsky S-58, but the nose profile was altered as a result of the installation of the turbine which, in the first production version, was a 1450shp Gazelle NGa.13. Later Wessex (Mk.2 and 5) were powered by twin Rolls-Royce Gnome engines and employed as troop transports. Westland built 356 Wessex in all (including those for the civil market): the HAS Mk.1 version for the Royal Navy; the HC Mk.2 tactical transport version for the RAF; the HAS Mk.3 antisubmarine version with 1550shp Gazelle NGa.18 turbine; the HU. Mk.5 for various roles on the Navy's commando carriers; the HAS Mk.31 for the Royal Australian Navy; the Wessex Mk.52 for the Iraqui Navy (12); the Wessex Mk.53 for Ghana (3); the Wessex Mk.54 for Borneo and the Wessex Mk.60 commercial version.

G.Apostolo "The Illustrated Encyclopedia of Helicopters", 1984

Westland "Wessex"

The company's success with the Whirlwind led to licence negotiations with Sikorsky to build the S-58, for Westland considered that this somewhat larger helicopter had excellent development potential with the introduction of turbine powerplant. A single example was imported and modified initially by the installation of an 820kW Napier Gazelle NGa.11 turboshaft engine, but the prototype and pre-production examples of the Westland Wessex had as powerplant the 1081kW Napier Gazelle Mk 161. The initial production version for the Royal Navy began to enter service on 4 July 1961, and the type was subsequently built in several variants. In 1993 the Wessex is in service only with No. 22 Sqn, RAF, on SAR duties, and The Queens' Flight at RAF Benson.


Wessex HAS.Mk 1: Royal Navy ASW version with Napier Gazelle Mk 161 powerplant

Wessex HC.Mk 2: high-performance development of Wessex HAS.Mk 1 for the RAF with two coupled Bristol Siddeley Gnome Mk 110/Mk 111 turboshafts, each rated at 1007kW; used primarily as transports (16 troops) or air ambulance (eight stretchers)

Wessex HAS.Mk 3: advanced Royal Navy ASW version with 1193kW Napier Gazelle Mk 165 and a comprehensive automatic flight-control system

Wessex HC.Mk 4: two aircraft as Wessex HC.Mk 2 but with VIP interiors for service with The Queen's Flight

Wessex HU.Mk 5: troop-carrying assault helicopter for the Royal Marine Commandos; similar to Wessex HC.Mk 2

Wessex HAS.Mk 31: 27 built for Royal Australian Navy, similar to Wessex HAS.Mk 1 but with 1174kW Napier Gazelle Mk 162 flat-rated to 1148kW; delivery began in August 1962 and when later given updated ASW systems became redesignated Wessex HAS.Mk 31B

Wessex Mk 52: 12 similar to Wessex HC.Mk 2 for Iraqi air force

Wessex Mk 53: three similar to Wessex HC.Mk 2 for Ghana air force

Wessex Mk 54: one similar to Wessex HC.Mk 2 for service in Brunei

Wessex Mk 60: civil version seating 10 to 16 passengers according to role, 15 survivors in rescue operations, or as an air ambulance can carry eight stretchers, two sitting casualties and a medical attendant

D.Donald "The Complete Encyclopedia of World Aircraft", 1997

Westland "Wessex"

The Westland Wessex is a turbine-powered development of the Sikorsky S-58.


Wessex HAS. Mk 1: Initial production version, developed for the Royal Navy, with one 1,450shp Napier Gazelle 161 turboshaft engine. Re-engined with a 1,100shp Gazelle NGa.11, flew for the first time 17 May 1957. Withdrawn from service.

Wessex HC. Mk 2: High-performance development of the Mk 1 with two coupled 1,350shp Bristol Siddeley Gnome Mk 110/111 turboshaft engines. Power limitation of 1,550shp at rotor head. Prototype converted from Wessex 1, flew for the first time 18 January 1962, and the first production model (XR588) 5 October 1962. Still in service.

Wessex Mk 3: Similar to Mk 1, but with 1,850shp Gazelle NGa.18 165 turboshaft engine. Not in service.

Wessex HCC. Mk 4: Queen's Royal Flight helicopter.

Wessex HC. Mk 5: SAR helicopter of the Royal Air Force based in Cyprus.

Wessex HU. Mk 5: Similar to Mk 2, for Commando assault duties from carriers of the Royal Navy. Design work began in April 1962 and construction of the prototype was started in May 1962. In service with A&EE (1) and 84 Squadron Akrotiri Cyprus (5).

Wessex HAS. Mk 31: Generally similar to Mk 1, but with a 1,540shp Gazelle Mk 162 engine. Ordered for the Royal Australian Navy for anti-submarine duties from HMAS Melbourne. Withdrawn from service.

Wessex Mk 52: Similar to Mk 2, for Iraqi Air Force. Withdrawn from service.

Wessex Mk 53: Similar to Mk 2, for Ghana Air Force. Withdrawn from service.

Wessex Mk 60: Civil version in service with Uruguayan Navy.

DESIGN FEATURES: Main and tail rotor each have four blades. Blades attached to hub by taper bolts. Main rotor blades fold manually. Rotor brake fitted. Shaft drive to main rotor through double epicyclic gear. Shaft drive to tail rotor through intermediate and tail gearboxes. Tail end folds to port and forward for stowage. Tail rotor carried at tip of vertical stabilising fin. Small horizontal stabiliser inset in leading-edge of fin.

STRUCTURE: All blades of light-alloy extruded spar and light-alloy bonded trailing-edge structure. The fuselage is a light-alloy semi-monocoque structure, with steel tube support structure for main rotor gearbox.

LANDING GEAR: Non-retractable tailwheel type. All three units fitted with Westland oleo-pneumatic shock-absorber. Dunlop wheels, tyres and hydraulic disc brakes. Tubeless treaded mainwheel tyres, size 6.00 x 11. Tailwheel tyre size 6.00 x 6.

POWER PLANT: (Mk 2): One Bristol Siddeley Gnome Mk 110 and one Gnome Mk 111 turboshaft engines, with Type 10 coupling gearbox. Rated at 1,350 shp per engine; 1,550shp at rotor head. Two flexible fuel tanks under cabin floor, total capacity 1,409 litres. Provision for carrying two 500 litre auxiliary tanks in cabin for ferry purposes. Refuelling point in starboard side of fuselage. Oil capacity 9 litres per engine, 19 litres in main gearbox.

POWER PLANT: (Mk 5): One Bristol Siddeley Gnome Mk 112 and one Gnome Mk 113 turboshaft engines, with Type 11 coupling gearbox. Otherwise as for Mk 2.

ACCOMMODATION: (Mk 2): Crew of one to three according to role. Up to 16 passengers in main cabin, on folding troop seats, or up to eight stretchers in banks of four. Doors on each side of flight deck and on starboard side of cabin.

ACCOMMODATION: (Mk 5): Crew of one to three according to role. Three fixed troop seats, and either 13 removable folding seats or eight stretchers, or 1,814kg of freight.

SYSTEMS: Compressor bleed air for heating. Ambient air circulation by fan. High-pressure hydraulic system for powered flying controls and 272kg capacity hoist. 24V DC electrical system, with two 6kW generators.

Jane's Helicopter Markets and Systems


- Australia's navy flew 27 Wessex helicopters on anti-submarine duties starting in August 1962.

- Westland's first prototype, a rebuilt Sikorsky S-58, flew on 17 May 1957.

- Users of the versatile Wessex include Australia, Brunei, Ghana and Iraq.

- The Wessex had top priority and in 1960 Westland halted work on a larger 'heavylift' helicopter.

- A Wessex fired AS.12 missiles at an Argentine commander in the Falklands.

- Australia's Wessexes used Gazelle engines instead of coupled Gnomes.

Technical data for Westland "Wessex" HC.Mk.2

Engine: 2 x Bristol Siddeley "Gnome" Mk.110 or Mk.111 turboshaft, rated at 1007kW, main rotor diameter: 17.07m, length with rotors turning: 20.04m, height: 4.93m, take-off weight: 6123kg, empty weight: 3767kg, max speed: 212km/h, range with max fuel: 769km

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Martyn Taylor, e-mail, 02.02.2022reply

How did the crew of the Wessex get in /out of the cockpit?

geoff elliott, e-mail, 13.09.2023 Martyn Taylor

Both pilot (STBD side)and co-pilot (Port Side) climbed up the outside steps into the opening cockpit sliding windows.

reply, 13.04.2021reply

Saved a few lives as well.

Nicia, e-mail, 05.03.2021reply

Sud-Aviation in France had developed its SA300 design as a medium transport helicopter in 1965 and this formed the basis of the SA330 Puma, to be built on production lines in France (by Sud-Aviation, and Aerospatiale from 1970) and the UK (by Westland). The other types involved were the Aerospatiale Gazelle and Westland Lynx.

Stewart William FORBES, e-mail, 17.05.2020reply

I was in Sharjah in 1970 (JT rigger) not sure which squadron, 72, 78. we had a Wessex return from an opp one day with his RH undercarriage brace sheared off and the wheel up by the jet pipe and burnt out. we had to build a platform out of bits and piece with old tyres on top. it took a while, 3 or 4 attempts and one in flight refuelling operation and a couple of crew changes as the captain had to hover 6 feet off the ground for a long time. the flight crews kept us in beer for a week after that anyone out there remember this

IAN SOMERS, e-mail, 24.11.2017reply

My Dads' last years in the FAA were at Culdrose. He had been on HMS Eagle one year. He was LEM (air) on the Wessex 1's. I can not remember which squadron he was with. He came home one afternoon with two photographs.

From the ground looking up at one of the Wessex coming down to touch down. The next photo showed the chopper on the ground right side collapsed and crumpled with right side undercarriage missing. Apparently as the aircraft was coming down the right side wheel fell off and bounced through the blades leaving the hapless pilot to just drop into the ground heavily before the thing had change to enter into a torque spin. He left all his photos when he passed away but I have not been able to find those of the wounded wessex. Is there anyone else still alive who remembers said incident.?

George Haloulakos, e-mail, 23.06.2017reply

One of the most famous aircraft in the Falkland Islands War was the Wessex HAS.3 (XP142) helicopter – affectionately known as “Humphrey” – stationed aboard the destroyer HMS Antrim. The Smithsonian Channel's Helicopter series has an episode titled "White Out" that presents a detailed first-hand account of how this helicopter was flown in the midst of icy blizzard conditions to complete what started as a special forces deployment, then became an evacuation when the weather worsened but turned into a rescue mission when two other helicopters crashed while trying to take off from Fortuna Glacier (islands of South Georgia). "Humphrey" was able to rescue all the special forces troops plus the downed helicopter crews! A few days later, this same Wessex helicopter was back in action, this time dropping depth charges on an enemy submarine. “Humphrey” is a testimony to a great aircraft handled with skill and uncommon valor!

Marcus Peake, e-mail, 25.08.2016reply

The Wessex 31A built for the Royal Australian Navy were not, strictly speaking, withdrawn from service. Twenty six of the twenty seven aircraft were converted to the 31B model, with upgraded engines and a better weapons system. The 31Bs were finally withdrawn from service in 1989, after some 36 years in service.

J Gwynfor Jones, e-mail, 13.01.2013reply

I was the killick S.E. on 848 sqd from 11 /69- 01 /72 and we lost an aircrewman who was a Sikh by the name of Jerry Vilku in a Wessex 5 in Culdrose in 1970. It crashed into the sea

Neil Chandler, e-mail, 17.05.2020 J Gwynfor Jones

Hi Only just come across this and I was very good friends with Jerry as was with him on 848 and remember one time on way back from Sembawang with the Albion we stopped in Durban and it was aparthied times and going ashore was a real problem. He was a great guy and my WREN wife Sue, who worked in the Flying Clothing Store, knew him just well. If you read this please get in touch Many thanks Neil (The Noo)


Crash Evsns, e-mail, 06.02.2022 Neil Chandler

I was messmates with Jerry at Culdrose when we were both rems on 707 before he went aircrew. I used help him fold his freshly washed turbans (memory fades but they must have been 10 feet long). I also have a publicity photo of him at Daedalus Club. My now wife Sylvia (Sifty Watson) is also in the photo.

Crash Evans - 848 sqdn 1970 - 72


Crash Evsns, e-mail, 06.02.2022 Neil Chandler

I was messmates with Jerry at Culdrose when we were both rems on 707 before he went aircrew. I used help him fold his freshly washed turbans (memory fades but they must have been 10 feet long). I also have a publicity photo of him at Daedalus Club. My now wife Sylvia (Sifty Watson) is also in the photo.

Crash Evans - 848 sqdn 1970 - 72


Bob Lunn, e-mail, 08.09.2023 Crash Evsns

I was in the mess with Jerry and also helped with his turban. We also tied his hair to the bed frame when asleep. I believe his younger brother was our newspaper boy in Blackheath, London. Jerry was a great guy.


Tim Watkin, e-mail, 24.02.2013reply

I was a pinky Tiff on both 707 NAS and then on a reformed 848 as part of a detached flight during the Falklands in '82. I always wondered if Bristow's or the FAA supplied the cabs for 'Full Metal Jacket'

anthony cooper, e-mail, 03.10.2010reply

What a lovely helicopter we used g-aync in the film full metal jacket in all 43 flying hours she was showing her age though and needed some tlc however that and the whirlwind series 3 take some beating

alan thompson, e-mail, 03.11.2010reply

The only two squadrons on hms albion 1962-64 was 845 with Wessex and 846 with Whirlwinds. I was on 845 for the whole of that commission as a Armourer. The Wessex were armed with four .303 browning machine guns, two each side on platforms over the wheels. Also a gpmg mounted in the doorway. We also had in the last year SS 11 missiles one each side The above version is wrong

Phil Williams, e-mail, 24.09.2013reply

I was an ABATA with RAN working on Wessex 31Bs .1971 to 1977.Does anyone know the main rotor blade weight? Would appreciate any answers.

geoff, e-mail, 28.03.2024 Phil Williams

Hi Phil,
Just came across this post.
If you are still interested:
I work at the RAF Tangmere Military Aircraft Museum and I am the crew chief in charge of a Wessex Mk 5 restoration there.
I have details from AP101C-0102 /4-1A (Mk2 and 4) Sect 2, Page 21 but the basic weights are still the same.
Length 26 Ft x 1Ft 5in. (Chord) Total weight 4 Blades 665Lb (166.25Lb each)
If you want any more information just let me know as I have all the Volumes 1-5 and Gnome engines Vols.


Phil Williams, e-mail, 24.09.2013reply

I was an ABATA with RAN working on Wessex 31Bs .1971 to 1977.Does anyone know the main rotor blade weight? Would appreciate any answers.

Jamie Bauld, e-mail, 23.11.2010reply

I had about 4 thousand hours flying in this aircraft on 814.826 sqdns royal navy and Ark Royal SAR Flight until the ship returned to Devonport to be scrapped and the last remaining Sqdn of wessex1 ,771 at Culdrose changed over to the twin engined version they had remained with the wessex1 as back up for Ark Royal SAR Flight very happy days
and fond memories of ths lovely aircraft

Neil "The Noo" Chandler, e-mail, 01.03.2022 Jamie Bauld

Hi Jamie,
Hope this finds you still with us mow we are men of senior years. Just wondered if you Knew Vic Warrington who I am still in touch with in Australia is not in best of health. Am am based at Exeter Airport now and just sent marines of to Bardufoss for Clockwork which I did the first ever one and the second over 50 years ago now!!! Hope to hear from you
Very kind regards Neil The Noo!!


ALLAN MORTON, e-mail, 27.09.2013reply

I remember the old Wessex helicopters that were used by the RAF Search and Rescue squadrons at Lossiemouth or Kinloss in the 80s and 90s when I was a member of Tayside Police MRT that operated in the Angus and Perthshire glens in Scotland.We flew in the Wessex on a few occasions up until,I think it was 1992,when they were withdrawn to be replaced by the Sea King.One memorable rescue would have been in the late 80s in the Angus glen of Glen Clova when we were asked to search a path called the Kilbo path ,in the middle of winter, for two 10 year dold boys and one of their fathers .This took pace in the middle of the night and we were helped halfway up the mountain along the path by a fantastic Wessex crew. There was some marvellous flying that night but as the aircraft could not enter the cloud we were obliged to jump from the hovering aircraft as it toughed ground with on front wheel onto a large rock and hovered,on what sounded like full power,whils we took the ten foot drop onto what was thankfully soft snow.
Prior to that we had been flying about for a few minutes in a wonderful moonlit night ,a great memory.We found the missing climbers but they had to be taken out by a Sea King as the Wessex was away refuelling. The Wessex was a rudimentery workhorse but it did the job that night and I am sure there are three persons walking about Scotland this day that would not be alive without the actions of the Wessex that night.

Nigel Toms, e-mail, 03.03.2011reply

i trained and worked on mk 1 /3 /and 5s as a smelly then transferred to aircrewman and again flew mk1 /3 and 5s before moving onto seakings /wasp etc . lovely aircraft and great fun climbing out onto the outside and climbing up to direct the pilot when speechless winching , health and safety would never allow that now

Sue Hobbs, e-mail, 24.03.2011reply

I belong to an ATC sqn that has a wessex hu mk5. We need new wheels and tyres. Anyone know where we can get some?

Neil "The Noo" Chandler, e-mail, 26.05.2011reply

Flew in the "5" as an aircrewman like Jamie above and was never let down. From Korea, Australia and South Africa to Norway (who could ever forget Clockwork!!) and the Med. Even Florida, Virgin Islands and Rockall. An amazing aircraft which has left many happy memories

Clive Hollins, e-mail, 21.11.2011reply

My apologies, A slip of the finger. Of course it was 845 Sqdn on the Albion. My confusion was that I was on the Albion twice. Once when it was a fixed wing carrier with 849C flight. At that time Albion carried Venoms,Seahawks, ASR Whirlwinds and Skyraiders. I believe that was the last fixed wing commission. After that I was posted to Boscombe down, Lee-on-Solent on courses then Brawdy. From there I went down to Culdrose again to the Wessex 845 Sqdn and back on the Albion for that little "Police Action" in the Far East. I was led to believe we would be doing anti submarine duties, but almost as soon as we formed up the ground crew personnel were asked to become aircrew as well as normal duties. The rest you know.

Peter Behenna, e-mail, 18.12.2011reply

What type of helicoptor was used in the film "FULL METAL JACKET" where Marines being dropped off in the field in
Viet Nam. Did Marine helicopter squardrons ever operate
this type of aircraft?

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