The Aerospatiale SA 341 Gazelle all-purpose lightweight helicopter originated as Aerospatiale project X 300 to meet a French army requirement for a light observation helicopter. The designation was changed to SA 340 soon afterwards. The finished design showed close affinity to the SA 318.C Alouette II, and eventually used the same Astazou II powerplant and transmission system. Unlike the Alouette II, however, the new helicopter features a fully-enclosed fuselage structure and has two pilots side by side, with full dual controls. It also introduced two innovations: the fenestron, or shrouded tail rotor, and a rigid modified Bolkow-type main rotor. And it showed every sign of sharing its predecessor's sales success and popularity.

While still in the final design stages the SA 340 attracted British interest, leading to a joint development and production share-out agreement signed on 22 February 1967 and officially confirmed on 2 April 1968. The first prototype, designated SA 340.001, was flown on 7 April 1967, and the second on 12 April 1968. These were followed by four pre-production SA 341 Gazelles (first flown on 2 August 1968), of which the third was equipped to British Army requirements, assembled in France, and then re-assembled by Westland in the UK as the prototype Gazelle AH.1. It was first flown on 28 April 1970.

On 14 May 1970 the first Aerospatiale-built SA 341 pre-production aircraft, in slightly modified form, establishing three new speed records for helicopters of its class, arousing even more foreign interest.

The first French production Gazelle, SA 341.1001, was cleared for its initial test flight on 6 August 1971; it had a longer cabin than its predecessors, an enlarged tail unit and an uprated Astazou IIIA engine. The initial Westland-assembled Gazelles followed early in 1972 (first flown on 31 January 1972).

Variants

SA 341B Gazelle AH.1: British Army version; Astazou IIIN engine; Nightsun searchlight, Decca Doppler 80 radar and automatic chart display; first Westland-assembled example flown on 31. January 1972; entered operational service on 6 July 1974 (total 158)

SA 341C Gazelle HT.2: Fleet Air Arm training versions; Astazou IIIN engine; stability-augmentation system and a hoist incorporated; first flown on 6 July 1972 and first entered service on 10 December 1974 (total 30)

SA 341D Gazelle HT.3: RAF training version; Astazou IIIN engine; stability-augmentation system; Schermuly flares installation; first deliveries to service on 16 July 1973 (total 14)

SA 341E Gazelle HCC.4: RAF communications version; Astazou IIIN engine (total 1)

SA 341F Gazelle: basic French army version; Astazou IIIC engine (total 166)

SA 341G Gazelle: civil commercial version; Astazou IIIA engine; officially certificated for passenger service on 7 June 1972; subsequently became the first helicopter to obtain US approval for operations under IFR Cat.1 conditions with a single pilot; also developed into a so-called 'Stretched Gazelle', with rear section of the cabin modified to provide additional 20cm legroom for the rear passengers

SA 341H Gazelle: military export version; Astazou IIIB engine; subject to licence-production agreement signed on 1 October 1971 with SOKO in Yugoslavia (total 112)

SA 342J Gazelle: civil version of SA 342L; 649kW Astazou XIV engine, improved fenestron tail rotor, increased take-off weight; approved for service on 24 April 1976; deliveries commenced in 1977

SA 342K Gazelle: military export version for 'hot and dry' areas; 649kW Astazou XIVH engine with momentum-separation shrouds over air intakes; first flown on 11 May 1973; initial sales to Kuwait.

SA 342L Gazelle: military counterpart of SA 342J; 649kW Astazou XIV engine; adaptable for wide range of armaments and equipment, including six Euromissile HOT anti-tank missiles

SA 342M Gazelle: French army antitank version with four Euromissile HOT missiles, SFIM APX M397 stabilised sight