Westland Wessex

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This article is about the helicopter. For the fixed-wing aircraft, see Westland IV.
Wessex
Wessex 1982.JPG
A Royal Navy Wessex HU.5 at Ascension Island in 1982
Role Helicopter
National origin United Kingdom
Manufacturer Westland Aircraft
Westland Helicopters
First flight 20 June 1958
Introduction 1961
Retired 2003 (Royal Air Force)
Primary users Royal Navy
Royal Air Force
Royal Australian Navy
Uruguayan Naval Aviation
Produced 1958-1970
Number built 356
Developed from Sikorsky H-34

The Westland Wessex is a British-built turbine-powered development of the Sikorsky S-58 "Choctaw", it was developed and produced under license by Westland Aircraft (later Westland Helicopters). One of the main changes from Sikorsky's S-58 was the replacement of the piston-engine powerplant with a turboshaft engine; the Wessex was the first helicopter in the world to be produced in large numbers that made use of a gas turbine propulsion system.[1] Early models were powered by a single Napier Gazelle engine, later builds used a pair of Rolls-Royce Gnome engines.

The Wessex was initially produced for the Royal Navy (RN) and later for the Royal Air Force (RAF); a limited number of civilian aircraft were also produced, as well as some export sales. The Wessex operated as an anti-submarine warfare and utility helicopter; it is perhaps best recognised for its use as a search and rescue (SAR) helicopter. The type entered operational service in 1961, and had a service life in excess of 40 years before being retired in Britain.

Design and development[edit]

In 1956, an American-built Sikorsky HSS-1 was shipped to Britain for Westland to use as a pattern aircraft. It was re-engined with a single Napier Gazelle turboshaft engine, and first flew in that configuration on 17 May 1957.[2] The first Westland-built Wessex XL727, designated a Wessex HAS.1, first flew on 20 June 1958.[2] The first production Wessex HAS1 were delivered to Royal Navy's Fleet Air Arm (FAA) in early 1960; the Wessex was the first helicopter operated by the FAA to be purpose-designed from scratch as an anti-submarine platform.[1]

In service, the Wessex was found to be a major improvement over the older Westland Whirlwind. The revolutionary turbine propulsion, in addition to giving the Wessex a larger load capacity, was quieter and generated less vibration, the latter quality was highly beneficial when treating casualties during flight; the Gazelle engine allowed for rapid starting and thus faster response times.[1] The Wessex could also operate in a wide range of weather conditions as well as at night, partly due to its use of an automatic pilot system. These same qualities that made the Wessex well-suited to the anti-submarine role also lent themselves to the search and rescue (SAR) mission, which the type would become heavily used for.[1]

A pair of Royal Navy Wessex helicopters in the flight deck of the HMS Intrepid, 1968

An improved variant, the Wessex HAS3, succeeded HAS1 in the anti-submarine role; it featured a more capable radar and better avionics, greater engine power, improved navigational features and a more advanced weapon system; the original HAS1 were hence re-tasked for SAR duties.[1] A 'commando assault' variant, the Wessex HU5, was also developed as a battlefield transportation helicopter; it was typically deployed upon on the navy's amphibious assault ships, such as the commando carrier HMS Albion, and heavily used to transport the Royal Marines.[3] The Wessex HU5 was powered by twin Rolls-Royce Gnome engines, which provided nearly double the power of the original HAS1 model and hugely expanded the aircraft's range and allowed for operations in a wider range of conditions; during the 1970s, the HU5 also started to be used for the SAR mission.[1]

As an anti-submarine helicopter, the Wessex could be alternatively equipped with a dipping sonar array to detect and track underwater targets or armed with either depth charges or torpedos; a single Wessex could not be equipped to simultaneously detect and attack submarines as this was beyond its carrying capacity. It was this limitation that soon led the Royal Navy to search for a more-capable helicopter that could provide this capability; which would ultimately result in Westland proceeding with the adaptation and production of another Sikorsky-designed helicopter in the form of the Westland Sea King.[4][5]

The Wessex was also successfully employed as a general-purpose helicopter for the RAF, capable of performing troop-carrying, air ambulance and ground support roles. The Wessex was the first of the RAF's helicopters upon which instrument flying, and thus night time operations, were realistically viable.[6] Unlike the Navy's Wessex fleet, which was largely composed of early single-engine, the RAF mandated that its Wessex helicopters should be all twin-engined; this was a major factor in the RAF's decision to reject the adoption of ex-FAA Wessex helicopters as they migrated to the newer Sea King.[7]

Operational history[edit]

United Kingdom[edit]

Overview[edit]

The Wessex was first used by the Royal Navy, which introduced the Wessex HAS.1 to operational service in 1961. Having been satisfied by the favorable initial performance of the Wessex but seeking to improve its avionics and equipment, the Navy soon pressed for the development of the improved HAS.3, which came into service in 1967. Operationally, younger models would be assigned to perform the key anti-submarine warfare and commando transport missions, while older and less capable models would be typically be assigned to land bases for search and rescue (SAR).[1]

The RAF became an operator of the Wessex in 1962; those helicopters used for air-sea or mountain rescue duties helped make the Wessex a particularly well known aircraft of the service and contributed to the saving of many lives during its time in service. As one of the RAF's standing duties, multiple Wessex helicopters were permanently kept on standby to respond to an emergency located anywhere within 40 miles of the British coastline within 15 minutes during daytime, at night hours this response time was decreased to 60 minutes.[8] SAR-tasked Wessex helicopters were also stationed abroad, such as at Cyprus.[9] The qualities of the Wessex were described as being "ideal for mountain flying".[10]

Troops embarking on a Westland Wessex during a training exercise

The Wessex often found itself being used on the battlefield as a utility transport; as well as delivering supplies and equipment, the Wessex could also transport small groups of troops.[11] Operationally the Wessex could lift less than the RAF's Bristol Belvedere helicopters but was more robust and required less maintenance; thus when the Belvedere was retired at the end of the 1960s, Wessex squadrons were often tasked with their former duties in support of the British Army on an ad-hoc basis.[12] In large-scale helicopter assault operations, the type could be escorted by the RAF's Hawker Siddeley Harriers.[13] The HC.4 variant of the Westland Sea King began to replace the Wessex in this capacity from the late 1970s onwards, although troop-carrying missions would continue into the late 1990s.[14]

The Wessex's service career featured long-term deployments to both Hong Kong and Northern Ireland to support internal security operations, performing transport and surveillance missions.[15] In Northern Ireland, the use of helicopters for supply missions proved a viable alternative to vulnerable road convoys; operations in this theatre led to the employment of various defensive equipment and countermeasures against the threat posed by small arms and man-portable air-defense systems (MANPADS).[16]

Wessex helicopters were also used by the Queen's Flight of the RAF to transport VIPs including members of the British Royal Family;[9] in this role, the helicopters were designated HCC.4 and were essentially similar to the HC.2, differences included an upgraded interior, additional navigation equipment and enhanced maintenance programmes.[17] Both Prince Philip and Prince Charles were trained Wessex pilots, occasionally they would perform as flying crew members in addition to being passengers on board the VIP services.[18] The Wessex was replaced in this role by a privately leased Sikorsky S-76 in 1998.[19]

Wartime operations[edit]

In 1962, an international crisis arose as Indonesia threatened confrontation over the issue of Brunei, which was not in the newly formed Federation of Malaya. By February 1964, a large number of RAF and RN helicopters, including Westland Wessex, were operating from bases in Sarawak and Sabah to assist Army and Marine detachments fighting guerilla forces infiltrated by Indonesia over its one thousand mile frontier with Malaysia. Having removed much of the anti-submarine equipment to lighten the aircraft, during the Borneo Campaign the Wessex was typically operated as a transport helicopter, capable of ferrying up to 16 troops or a 4,000 pound payload of supplies directly to the front lines.[20] Alongside the Westland Scout, the Wessex emerged as one of the main workhorses of the campaign, roughly half were operated directly from land bases and would regularly rotate with those stationed on RN vessels stationed off shore.[21][22]

Around 55 Westland Wessex HU.5s participated in the Falklands War, fighting in the South Atlantic in 1982. Their prime role was the landing, and moving forward, of Rapier missile systems, fuel, artillery and ammunition.[citation needed] On 21 May 1982, 845 Squadron's Wessex HU.5s supported British landings on East Falkland. The type was heavily used throughout the conflict for the transportation and insertion of British special forces, including members of the Special Air Service (SAS) and the Special Boat Service (SBS).[9] A total of nine Wessex (eight HU.5s and one HAS.3) were lost during the Falklands campaign.[23] Two HU.5s of 845 Squadron crashed on the Fortuna Glacier in South Georgia during an attempt to extricate members of the SAS, six of 848 Squadron's Wessex HU.5s were lost when the container ship Atlantic Conveyor was sunk[24] and the HAS.3 aboard HMS Glamorgan (D19) was destroyed when the ship was struck by an Exocet missile.[25]

Civilian operations[edit]

Wessex 60 of Bristow Helicopters at North Denes airfield, Norfolk, in 1970 during support flights to the growing North Sea Oil industry

A civilian version of the helicopter, the Wessex 60, was also manufactured and supplied to a number of civilian operators, including Bristow Helicopters, one of the biggest rotary-wing operators in the world.[26] Bristows flew them from various UK airfields and helicopter pads to support the growing North Sea Oil industry until they were withdrawn in 1982.

Australia[edit]

In April 1961, the Royal Australian Navy (RAN) announced that they had selected the Westland Wessex to become the standard service helicopter from their ships and its intention to purchase roughly 30 for anti-submarine patrols, casualty evacuations, and fleet communications duties.[27] The RAN formally accepted the first two of 27 Wessex helicopters in September 1963;[28] 817 Squadron was the first to operate the type; the Wessex and its dunking sonar array quickly proved to be the most effective anti-submarine platform as yet seen in the RAN.[29][30]

The Wessex was a major operational shift for the Fleet Air Arm, enabling the RAN to proceed with the conversion of the aircraft carrier HMAS Melbourne as an anti-submarine platform.[31] In typical carrier operations, a Wessex would be deployed during the launch and recovery of fixed-wing aircraft as a guard helicopter; during anti-submarine patrols, routine procedure was to have one Wessex airborne to actively screen the ship while a second would be fully armed and prepared for operations, such an arrangement was used during troop transport deployments to Vietnam during the 1960s.[30] Performing Search and Rescue sorties became another valued role of the type; in 1974, multiple Wessex helicopters participated in the relief effort in Darwin in the aftermath of Cyclone Tracy.[30]

While the Wessex proved to be too large to reasonably operate from most of the RAN's destroyers, it was found to be well suited as a troop-transport helicopter from heavy landing ships and larger vessels.[32] By 1980, the Wessex was no longer being used for anti-submarine operations, having been replaced by the more advanced and capable Westland Sea King in this capacity, instead remaining Wessex helicopters were retained to perform its secondary roles as a plane guard, search and rescue platform, and as a utility transport helicopter.[30][33]

Variants[edit]

A Wessex HAS.1 at the Imperial War Museum at Duxford (UK)
A Wessex at the Australian National Maritime Museum
Wessex HAS.1
RN utility, anti-submarine warfare, later air-sea rescue only, 140 built, some later converted to HAS.3.
Wessex HC.2
RAF Troop carrier for up to 16 troops, One prototype converted from HAS1 and 73 built.
Wessex HAR.2
RAF search and rescue conversions.
Wessex HAS.3
RN anti-submarine version with improved avionics with a radome on the rear fuselage, 3 new-build development aircraft and 43 converted from HAS.1
Wessex HCC.4
VVIP transport for the Queens Flight, two built
Wessex HU.5
RN service troop transporter, carried 16 Royal Marines, 101 built
Wessex HAS31
Royal Australian Navy anti-submarine warfare model, 27 built.
Wessex HAS31B
Updated anti-submarine warfare model for the Royal Australian Navy.
Wessex 52
military transport version of the HC.2 for the Iraqi Air Force, 12 built.
Wessex 53
Military transport version of the HC.2 for the Ghana Air Force, two built.
Wessex 54
Military transport version of the HC.2 for the Brunei Air Wing, two built
Wessex 60
Civilian version of the Wessex HC.2, 20 built.

Notable accidents[edit]

Operators[edit]

Military operators[edit]

An Australian Wessex helicopter in flight, behind is the HMAS Melbourne (R21). Five additional Wessexs line the flight deck
External video
Westland Wessex from RAF Aldergrove on exercise with Mourne mountain rescue team
Wessex performing various maneuvers during public display
 Australia
 Bangladesh
 Brunei
 Ghana
 Iraq
 Oman
 United Kingdom
 Uruguay

Civil Operators[edit]

 United Kingdom

Specifications (Wessex HC.2)[edit]

Data from Westland Aircraft since 1915[59]

General characteristics

  • Crew: Two pilots (civilian type 60 Wessex cleared for single pilot operation[60])
  • Capacity: 16 troops or 8 stretchers
  • Length: 65 ft 10 in (20.07 m)
  • Rotor diameter: 56 ft 0 in (17.07 m)
  • Height: 15 ft 10 in (4.83 m)
  • Disc area: 2,463 ft² (229 m²)
  • Empty weight: 8,340 lb (3,767 kg)
  • Loaded weight: 13,500 lb (6,136 kg)
  • Powerplant: 2 × Rolls-Royce Gnome H.1200 Mk.110/111 turboshaft, 1,350 shp (1,007 kW) (limited to 1,550 shp (1,156 kW) total[2]) each

Performance

Notable appearances in media[edit]

See also[edit]

Related development
Aircraft of comparable role, configuration and era

References[edit]

Citations
  1. ^ a b c d e f g "The Wessex Helicopter". royalnavy.mod.uk, Retrieved: 14 January 2014.
  2. ^ a b c Taylor 1965, p.169.
  3. ^ McGowen 2005, p. 84.
  4. ^ Plamondon 2010, p. 74.
  5. ^ McGowen 2005, pp. 84-85.
  6. ^ Royal Air Force Historical Society 2000, p. 83.
  7. ^ Royal Air Force Historical Society 2000, pp. 95-96.
  8. ^ Motum 1991, p. 201.
  9. ^ a b c Crawford 2003, p. 38
  10. ^ Royal Air Force Historical Society 2000, pp. 72-73.
  11. ^ Royal Air Force Historical Society 2000, pp. 37-38.
  12. ^ Ripley 2008, pp. 42-43.
  13. ^ Royal Air Force Historical Society 2000, p. 42.
  14. ^ Ripley 2008, pp. 43, 51.
  15. ^ Royal Air Force Historical Society 2000, pp. 44-48.
  16. ^ Ripley 2008, p. 44.
  17. ^ Piggott 2005, pp. 174-175.
  18. ^ Piggott 2005, p. 179.
  19. ^ Piggott 2005, pp. 180, 188.
  20. ^ Dunstan 2003, pp. 14-15.
  21. ^ Fowler 2006, pp. 18, 39.
  22. ^ Ripley 2008, p. 42.
  23. ^ Burden et al. p. 188.
  24. ^ Burden et al. 1986, p. 287.
  25. ^ Benson, p.305
  26. ^ Harrison, Neil. "World's Biggest VTOL Carrier." Flight International, 1 May 1969, p. 725.
  27. ^ "Navy Chooses U.K. Helicopters." The Age, 21 April 1961. p. 5.
  28. ^ "Helicopters for the Navy." The Age, 13 September 1963. p. 4.
  29. ^ "Navy forms Squadron of Helicopters." The Age, 13 June 1963. p. 6.
  30. ^ a b c d "817 Squadron History." navy.gov.au, Retrieved: 15 February 2014.
  31. ^ Grey 2008, p. 229.
  32. ^ "723 Squadron History." navy.gov.au, Retrieved: 15 February 2014.
  33. ^ "Helicopters: Demanding common role required." Sydney Morning Herald, 14 October 1980. p. 6.
  34. ^ "Helicopter World Market 1968 pg. 48". flightglobal.com. Retrieved 10 March 2013. 
  35. ^ Robertson 1987, p.221
  36. ^ Hansard 1803-2005 - 15 January 1975 - Written Answers (Commonm) - Overseas Development - Bangaladesh
  37. ^ "Helicopter World Market 1968 pg. 49". flightglobal.com. Retrieved 10 March 2013. 
  38. ^ a b "Helicopter World Market 1968 pg. 52". Retrieved 2013-03-10. 
  39. ^ a b c Halley 2001, p. 82
  40. ^ Westland Wessex XR525
  41. ^ "Westland Wessex RAF". Retrieved 10 March 2013. 
  42. ^ a b c d e Halley 1980, p. 355.
  43. ^ a b Donald, David. "Westland Wessex HCC.4: Queen's Flight helicopters retire". World Air Power Journal Volume 34, Autumn/Fall 1998. London:Aerospace Publishing. p. 29. ISBN 1-86184-019-5. ISSN 0959-7050.
  44. ^ 60 Squadron. Royal Air Force. Retrieved 2 April 2013.
  45. ^ Ashworth 1989, p. 162.
  46. ^ Halley 1980, p. 140.
  47. ^ a b Halley 2001, p. 84
  48. ^ "Westland Wessex Fleet Air Arm". Retrieved 10 March 2013. 
  49. ^ a b c d e f g Thetford 1982, p. 355.
  50. ^ a b Burden et al. 1986, p. 283.
  51. ^ Burden et al. 1986, p. 267.
  52. ^ a b Burden et al. 1986, p. 280.
  53. ^ Burden et al. 1986, p. 271.
  54. ^ Thetford 1982, p. 359.
  55. ^ Burden et al. 1986, p. 279.
  56. ^ "Fuerza Aerea Uruguaya Wessex". Retrieved 10 March 2013. 
  57. ^ "Aviación Naval Uruguaya Wessex". Retrieved 10 March 2013. 
  58. ^ "Bristow Helicopters Westland Wessex Series 60". hmfriends.org.uk. Retrieved 10 March 2013. 
  59. ^ James 1991, pp. 362, 364.
  60. ^ Harrison Flight International 1 May 1969, p. 727.
Bibliography
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  • Crawford, Stephen. Twenty First Century Military Helicopters: Today's Fighting Gunships. Zenith Imprint, 2003. ISBN 0-76031-504-3.
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External links[edit]