File:Westland Wessex HAS.1 ‘XM330’.jpg

English: c/n WA.11

Built 1959 and used for trials and test work for her entire career. She served with the Aeroplane & Armament Experimental Establishment (A&AEE), the Royal Aircraft Establishment (RAE) at Farnborough, the Empire Test Pilots School (ETPS) at Boscombe Down and the Air Torpedo Development Unit. She was retired in 1983 and joined the museum here in 1994. The Helicopter Museum Weston-super-Mare, North Somerset, UK 2nd October 2020

The following information is from The Helicopter Museum website:-

“In 1956 Westland took a piston-engined Sikorsky S-58 and replaced the 1525hp radial engine in the nose with the British Napier Gazelle turboshaft, an early example of the now common use in helicopters of a turbojet engine adapted to drive a shaft connected to a gearbox and rotor system In its initial version as the Wessex Mk.1, the anglicised WS-58 was developed for the Royal Navy for the anti-submarine warfare role with an electronic flight control system and auto-stabilisation to permit night operations. The new 1450shp turboshaft not only offered valuable power reserves and greater reliability, but was smaller and half the weight of the piston engine allowing the helicopter to carry more. It also ran on kerosene, eliminating the need to store high octane petrol aboard ships. Entering service in 1961, the last Wessex Mk.1 was retired in 1979, by which time its roles had expanded to include commando assault and search and rescue operations.

This example (XM 330) was a pre-production aircraft used for trials work, initially at Boscombe Down from whence it carried out tropical trials in Libya and Malta in 1961, and anti-tank missile firing tests on Salisbury Plain in 1962. The aircraft was then transferred to the Royal Aircraft Establishment at Farnborough for experimental test work.”