|Aerospatiale SA-341/342 "Gazelle"|
The SA 341 Gazelle all-purpose lightweight helicopter began as a proposal for a new observation helicopter for the French army. It was re-named the SA 340 soon afterwards. The finished design looked like the well-known Alouette and initially used the same engine. Unlike the Alouette, the Gazelle features a fully enclosed fuselage structure and, while it can be flown by a single pilot, has provision for two pilots with side-by-side seating.
In 1967, Britain joined a production-sharing agreement and began its long association with the Gazelle as a military helicopter. Westland performed final assembly of the first British military version in 1970.
The SA 341 designation reappeared in 1970, when the Gazelle established three world helicopter speed records. The upgraded SA 342 first flew in 1976. About a dozen versions of the Gazelle are in wide use, including military variants employed by 27 countries, and are performing with distinction. France has nearly 300 heavily-armed Gazelles.
R.Jackson "Helicopters. Military, Civilian, and Rescue Rotorcraft", 2005
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).
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
D.Donald "The Complete Encyclopedia of World Aircraft", 1997
First flown in July 1969 after many alterations including a trial rigid-rotor system, developed by MBB of Germany, the SA.341 Gazelle went into joint production with the UK and France. The Gazelle featured a semi-rigid rotor and composite blades, together with a newly designed 'Fenestron' tail rotor. The Fenestron is a shrouded tail-rotor with a high fin to improve flight characteristics at high speed. It gives an added safety factor by guarding against tail rotor-blade strikes during landings. Under another Anglo-French agreement the Gazelle was built under licence by Westland Helicopters for the British Army, Air Force and Royal Navy. These first entered service in 1973 in the training role, but later the Gazelle was chosen by the Army as a light observation/liaison helicopter joining the Army Air Corps. Powered by a single Turbomeca Astazou IIIA engine developing around 440kW, the Gazelle has a maximum speed of 264kph and a range of 670km. The French Army use the Gazelle in the armed anti-tank role fitted with up to six HOT missiles. This version, the SA.342M/L1, is powered by an uprated Turbomeca Astazou XIVM turbine developing 650kW. The Gazelle has proved successful with overseas customers, being used in the armed/anti-tank/observation/civilian and training roles. As well as the UK, the Gazelle has been built under licence by Egypt and Yugoslavia.
P.Allen "The Helicopter", 1996
The SA.341, whose SA.340 prototype F-WOFH flew for the first time on 7 April 1967, is a light observation and general purpose helicopter in the tradition of the ubiquitous Alouette, which it is intended to supersede in the early 1970s. It is also one of the types specified in the January 1967 Anglo-French helicopter agreement for large-scale production for the British and French armed forces (six hundred and one hundred respectively). Following the first flight, development continued throughout 1967 at Sud-Aviation's factory at Marignane, near Marseille. This first aircraft utilises the tail rotor and skid of the Alouette II and the engine and transmission system of the Alouette II Astazou, but the second prototype (F-ZWRA, first flown on 17 April 1968) was representative of production SA.341's in having the Astazou IIN2 and a 'solid' vertical fin with a circular cut-out in its centre, within which its small tail rotor rotates, so reducing the risk of injury from this feature when the aircraft is on or near the ground. The main rotor blades, made of laminated glassfibre, are of the type developed by Bolkow of Germany in collaboration with Sud-Aviation. The cabin, whose shape is much superior aerodynamically to the Alouette, will seat 5 occupants and their baggage and will contribute to a useful increase in performance.
K.Munson "Helicopters And Other Rotorcraft Since 1907", 1968
Sud-Aviation began working on a modern replacement for its Alouette II as long ago as 1966. The aim was to develop a light observation helicopter with accommodation for five, which would use some of the main components of the Alouette II but be technically less complex. Sud-Aviation produced the SA.340 prototype at the beginning of 1967, with an Astazou UN turbine and the same transmission, landing skids, anti-torque rotor and tail plane as the Alouette.The rotor was of the rigid type with three blades of reinforced plastic designed by Bolkow, but in the original project it was planned to replace the two-blade tail rotor by a 13-blade fan shrouded in a type of vertical fin known as a "fenestron". This was applied to the second prototype which closely resembled the production SA.341 and flew a year later, on 17 April 1968.
The SA.341, named Gazelle, was also included in the joint production agreement with Westland in the UK.
G.Apostolo "The Illustrated Encyclopedia of Helicopters", 1984
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Technical data for Aerospatiale SA-341 "Gazelle"
Engine: 1 x Turbomeca Astazou IIIA turboshaft, rated at 440kW, main rotor diameter: 10.50m, overall length: 11.97m, height: 3.15m, take-off weight: 1800kg, empty weight: 908kg, max speed: 310km/h, cruising speed: 233km/h, rate of climb: 9.0m/s, service ceiling: 5000m, range with max fuel: 670km, range with 500kg payload: 360km