Westland Wessex The Westland Wessex is a British turbine - powered version of the Sikorsky S - 58 " Choctaw " , developed under license by Westland Aircraft ( later Westland Helicopters ) , initially for the Royal Navy , and later for the Royal Air Force ( RAF ) . The Wessex operated as an anti - submarine warfare and utility helicopter in multiple nations , it is perhaps most well known in Britain for its service as a search and rescue ( SAR ) helicopter . The type first entered service in 1961 . Design and development . An American - built Sikorsky HSS - 1 was shipped to Westland in 1956 to act as a pattern aircraft . It was re - engined with a Napier Gazelle turboshaft engine , and first flew in that configuration on 17 May 1957 . The first Westland - built Wessex " XL727 " , designated a " Wessex HAS . 1 " , first flew on 20 June 1958 . The type first began performing anti - submarine duties in 1961 , operated by the Royal Navy Fleet Air Arm . As an anti - submarine helicopter , the Wessex could track targets but not engage them with either depth charge s or torpedo s as this was beyond its carrying capacity ; this limitation led to Westand and the Royal Navy quickly seeking a helicopter that could provide that capability , resulting in the acquisition and adaption of another Sikorsky - designed aircraft to produce the Westland Sea King . The Wessex helicopter was successfully adapted in the early 1960s as a general - purpose helicopter for the RAF , capable of performing troop - carrying , air ambulance and ground support roles . In contrast with the HAS . 1 , it used twin Rolls - Royce Gnome engines . These marks ( HC . 2 , HCC . 4 , HU . 5 ) had a single large exhaust on each side of the nose , the Gazelle - powered examples having a pair of smaller exhausts on either side . Operational history . Britain . Overview . The Wessex was first used by the Royal Navy , introducing the " HAS . 1 " to meet the service ' s growing need to counter the expanding capabilities and numbers of submarines . The Navy would quickly press the development of the HAS . 1 into the improved " HAS . 3 " , which came into service in 1967 . It saw embarked service on the County class destroyer s . The HAS . 3 could be identified by a dorsal radome and strake extending behind the " hump " . 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 . Wessex helicopters were also used by the Queen ' s Flight of the RAF to transport VIP s 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 . 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 operated as a large 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 . Civilian operations . Twenty Wessex 60 helicopters powered by the Bristol Siddeley Gnome H1200 engine were supplied to civilian operators including Bristow Helicopters of Redhill in Surrey . 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 . 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 . 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 . The RAN formally accepted the first two of 27 Wessex helicopters in September 1963 ; 817 Squadron was the first to operate the type . By 1980 , the Wessex was no longer being used for anti - submarine operations , instead performing the personnel transport mission as a utility helicopter instead .