Westland Aircraft Westland Aircraft was a British aircraft manufacturer located in Yeovil in Somerset . Formed as a separate company by separation from Petters Ltd just before the start of the Second World War , Westland had been building aircraft since 1915 . During the war the company produced a number of generally unsuccessful designs , but their Lysander would serve as an important liaison aircraft with the Royal Air Force . After the war the company focused on helicopter s , and was merged with several other British firms to create Westland Helicopters in 1961 . History . Foundation . In 1915 the Westland Aircraft Works was founded as a division of Petters Limited in response to government orders for the construction under licence of initially 12 Short Type 184 seaplanes , followed by 20 Short Type 166 aircraft . Orders for other aircraft followed during the First World War , including the Sopwith 1½ Strutter , the de Havilland designed Airco DH . 4 , Airco DH . 9 and Airco DH . 9A and the Vickers Vimy . The name " Westland " was chosen by Mrs Petter as new land purchased as part of an expansion in 1913 at West Hendford which had been earmarked for a new foundry , but ended up becoming the centre for aircraft production . As a result of the experience gained in manufacturing aircraft under licence , Westland began to design and build its own aircraft , starting with the Westland N . 1B in 1917 , which was followed in 1918 by the Wagtail and the Weasel . Following the end of war , Westland produced the Limousine and Woodpigeon light aircraft for the civilian market , but most successful was the Wapiti close support aircraft . In 1935 Petters split its aircraft manufacturing from its aircraft engine concerns to form Westland Aircraft Limited , based in Yeovil , Somerset . World War Two . The Whirlwind was the UK ' s first cannon - armed fighter and faster than many other British aircraft at the time but was troubled by the inability of Rolls - Royce to produce the engines . The Lysander army co - operation aircraft was displaced for reconnaissance as too vulnerable but found favour for specialist missions into occupied Europe carrying agents . Westland tendered designs for new aircraft during the war but only the Welkin was accepted . The Welkin was a twin - engine high altitude design to intercept attempts by high - flying German bombers to attack Britain . When the threat never appeared production was limited . For much of the war their factories were used to build Supermarine Spitfire s , after the Supermarine factory in Southampton was bombed out of action during the Battle of Britain ; indeed Westlands built more Spitfires than any other manufacturer . Westland would then go on to be the major designers of the Supermarine Seafire , a navalised conversion of the Spitfire . Post War success . The Westland Wyvern was a post - war design of carrier - based strike - fighter for the Fleet Air Arm serving up to 1958 . Post - war the company decided to get out of fixed - wing aircraft and concentrate solely on helicopters under a licensing agreement with Sikorsky . This upset W . E . W . Petter , the chief designer , who left to form a new aircraft division at English Electric that would go on to be very successful . Production started with the Sikorsky S - 51 flying for the first time in 1948 and as the Westland - Sikorksy Dragonfly entering service with the Royal Navy and RAF from 1950 . Westland developed an improved version the Widgeon which was not a great success . Success with the Dragonfly was repeated with the Sikorsky S - 55 which became the Whirlwind , and a re - engined Sikorsky S - 58 in both turboshaft and turbine engine powered designs as the Wessex . In 1952 Westland decided on three helicopter designs for possible development : None of the three Westland helicopter , nor the even larger ( rotor diameter ) W - 90 suggested for development in 1952 advanced further than the paper study . Westland did progress as a private venture a large space - frame cargo helicopter design using a Sikorksy rotor head - the Westland Westminster - but this was dropped later in favour of the government funded Fairey Rotodyne . Forced mergers . The chairmanship of Eric Mensforth from 1953 – 1968 marked the start of the transition . From 1959 – 1961 the British government forced the consolidation of 20 or so British aviation firms into three larger groups with the threat of withheld contracts and the lure of project funding . While the majority of fixed - wing aircraft design and construction lie in the British Aircraft Corporation and the Hawker Siddeley Group the helicopter divisions of Bristol , Fairey and Saunders - Roe ( with their hovercraft ) were merged with Westland to form Westland Helicopters in 1961 . Subsidiaries . Normalair was created to continue the development and marketing of the pressure relief valves used in the Welkin project .