Westland Wessex Helicopter (1961-1998) (RN & RAF)

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SKB
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Westland Wessex Helicopter (1961-1998) (RN & RAF)

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Image
^ A Wessex in 1982

Introduction
The Westland Wessex is a British-built turbine-powered development of the Sikorsky H-34, it was developed and produced under license by Westland Aircraft (later Westland Helicopters). One of the main changes from Sikorsky's H-34 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. 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
In 1956, an American-built S-58 was shipped to Britain for Westland to use as a pattern aircraft. Initially assembled with its Wright Cyclone, it was demonstrated to the British armed services leading to a preliminary order for the Royal Navy. For British production, it was re-engined with a single Napier Gazelle turboshaft engine, first flying in that configuration on 17 May 1957. The lighter (by 600 lb) Gazelle engine meant some redistribution of weight. The first Westland-built Wessex serial XL727, designated a Wessex HAS.1, first flew on 20 June 1958. 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.

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. 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.

An improved variant, the Wessex HAS3, succeeded the 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. 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. 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.

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.

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 in which instrument flying, and thus night time operations, were realistically viable. Unlike the Navy's Wessex fleet, which was largely composed of early single-engine models, 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 the navy migrated to the newer Sea King.


Operational History (UK)
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).

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. SAR-tasked Wessex helicopters were also stationed abroad, such as at Cyprus. The qualities of the Wessex were described as being "ideal for mountain flying".

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. 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. In large-scale helicopter assault operations, the type could be escorted by the RAF's Hawker Siddeley Harriers. 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.

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. 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).

Wessex helicopters were also used by the Queen's Flight of the RAF to transport VIPs including members of the British Royal Family; 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. 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. The Wessex was replaced in this role by a privately leased Sikorsky S-76 in 1998.


Wartime Operations (UK)
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 campaign in Borneo 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. 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.

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. 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). A total of nine Wessex (eight HU.5s and one HAS.3) were lost during the Falklands campaign. 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 and the HAS.3 aboard HMS Glamorgan (D19) was destroyed when the ship was struck by an Exocet missile.


Variants
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.


Specifications (Wessex HC.2)
Crew: Two pilots (civilian type 60 Wessex cleared for single pilot operation)
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) each
Maximum speed: 132 mph (115 knots, 213 km/h)
Cruise speed: 122 mph (106 knots, 196 km/h)
Range: 310 mi (270 nmi, 499 km) with standard fuel
Service ceiling: 12,000 ft (3,660 m)
Rate of climb: 1,650 ft/min (8.4 m/s)

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SKB
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Re: Westland Wessex Helicopter (1961-1998) (RN/RAF)

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marktigger
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Re: Westland Wessex Helicopter (1961-1998) (RN & RAF)

Post by marktigger »

remember seeing the wessex for many years in Northern Ireland, along with the Beaver, Scout, gazelle and Lynx was some of the background noise of my childhood

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