The Gazelle helicopter (SA 341 / SA 342) is a multi-purpose, lightweight utility / attack helicopter manufactured by Aerospatiale Helicopter Corporation, France. It is one of the fastest helicopters and serves several branches of the British Armed Forces including the Royal Air Force, Royal Navy, Army and Royal Marines in various applications.
The helicopter is used in approximately 23 countries, primarily for surveillance and reconnaissance. It is also used for military applications such as attack, anti-tank, anti-helicopter, transport and training. It can accommodate one pilot and four passengers.
Fenestron / fantail tail rotor
The SA 341 is the first helicopter to be fitted with a fenestron or fantail. The fenestron is a shrouded tail-rotor that enhances flight characteristics at high speed and reduces noise. The helicopter also features a round, glassed-in cockpit, three main rotor blades and 13 fenestron blades in the tail rotor.
The three main rotor blades are mounted on top of the fuselage at the back of the cabin and are made from composite materials.
The Gazelle proved unsuitable for operations in Afghanistan because of the hot and dry climate. In Afghanistan SA341s cannot fly between 11am to 11pm during summer because heat can damage the engines.
British interest in a utility helicopter led to the development of the Gazelle. In February 1967 the British Army signed a contract with Westland Helicopters for the Gazelle’s development.
Westland and Aerospatiale formed a joint venture in 1968 to develop the helicopter. The Gazelle made its maiden flight on 7 April 1967. Westland completed the final assembly of SA 341 in 1970.
The SA 342M, SA 341F and Gazelle Viviane were developed for surveillance and reconnaissance.
The SA 342 series made its first flight in 1976. A state-of-the-art anti-tank helicopter, Gazelle Viviane is equipped with a Viviane thermal imagery system, designed to capture images on battlefields.
The SA 341’s avionics include general instruments, standby magnetic artificial horizon, slip indicator, Bendix / King SM-4001 moving map, global positioning systems (GPS), King KI-825 EHSI Kit, King KRA-10A radar altimeter kit and Garmin GNS-430 NAV / COMM / GPS.
It is also equipped with King KX-165A NAV / COMM, a Bendix / King KT-76C transponder and a Garmin GMA-340H audio panel.
The Gazelle has direct voice input (DVI) systems that control avionics instruments through aircrew helmet microphones and an intercom. The DVI system is manufactured by QinetiQ. It also has an infrared signature suppressor.
The SA 341 is equipped with a GIAT M621 20mm cannon, four AT-3 ATGMs and two SA-7, 128mm or 57mm rockets and a 7.62mm machine gun in cabin.
The GIAT M621 is an automatic 20mm cannon manufactured by Nexter for helicopters and armoured vehicles. The length and width of the M621 cannon are 2,207mm and 202mm respectively. The height and weight are 245mm and 45.5kg respectively.
The AT-3 ATGM is an anti-tank guided missile used to demolish heavily armoured tanks and fighting vehicles. The SA-7 is a low-altitude surface-to-air missile system. The length and diameter of the SA-7 are 1.44m and 72mm respectively.
The Gazelle is powered by a Turbomeca Astazou IIIA turboshaft engine. The engine generates about 440kW of output power. The Astazou IIIA engine is primarily used for civil and military applications.
The Gazelle can climb at a rate of 12.2m/s. The helicopter has a cruise speed of 264km/h and can fly at a maximum speed of 310km/h. The range and service ceiling of the helicopter are 500 miles and 20,000ft respectively. The maximum take-off weight of the helicopter is 1,800kg, while the endurance is 3.5h.
- SA 340: First prototype, first flown on 7 April 1967 with a conventional Alouette type tail rotor.
- SA 341: Four pre-production machines. First flown on 2 August 1968. The third was equipped to British Army requirements and assembled in France as the prototype Gazelle AH.1. This was first flown on 28 April 1970.
- SA 341.1001: First French production machine. Initial test flight 6 August 1971. Featured a longer cabin, an enlarged tail unit and an uprated Turbomeca Astazou IIIA engine.
- SA 341B (Westland Gazelle AH.1): Version built for the British Army; Featured the Astazou IIIN2 engine, capable of operating a nightsun searchlight, later fitted with radio location via ARC 340 radio and modified to fire 68mm SNEB rockets. First Westland-assembled version flown on 31 January 1972, this variant entered service on 6 July 1974. A total of 158 were produced. A small number were also operated by the Fleet Air Arm in support of the Royal Marines.
- SA 341C (Westland Gazelle HT.2): Training helicopter version built for British Fleet Air Arm; Features included the Astazou IIIN2 engine, a stability augmentation system and a hoist. First flown on 6 July 1972, this variant entered operational service on 10 December 1974. A total of 30 were produced.
- SA 341D (Westland Gazelle HT.3): Training helicopter version built for British Royal Air Force; Featuring the same engine and stability system as the 341C, this version was first delivered on 16 July 1973. A total of 14 were produced.
- SA 341E (Westland Gazelle HCC.4): Communications helicopter version built for British Royal Air Force; Only one example of this variant was produced.
- SA 341F: Version built for the French Army; Featuring the Astazou IIIC engine, 166 of these were produced. Some of these were fitted with an M621 20-mm cannon.
- SA 341G: Civil variant, powered by an Astazou IIIA engine. Officially certificated on 7 June 1972; subsequently became first helicopter to obtain single-pilot IFR Cat 1 approval in the US. Also developed into “Stretched Gazelle” with the cabin modified to allow an additional 8 inches (20cm) legroom for the rear passengers.
- SA 341H: Military export variant, powered by an Astazou IIIB engine. Built under licence agreement signed on 1 October 1971 by SOKO in Yugoslavia.
- SA 342J: Civil version of SA 342L. This was fitted with the more powerful 649 kW (870 shp) Astazou XIV engine and an improved Fenestron tail rotor. With an increased take-off weight, this variant was approved on 24 April 1976, and entered service in 1977.
- SA 342K: Military export version for “hot and dry areas”. Fitted with the more powerful 649-kW (870-shp) Astazou XIV engine and shrouds over the air intakes. First flown on 11 May 1973; initially sold to Kuwait.
- SA 342L: Military companion of the SA 342J. fitted with the Astazou XIV engine. Adaptable for many armaments and equipment, including six Euromissile HOT anti-tank missiles.
- SA 342M: French Army anti-tank version fitted with the Astazou XIV engine. Armed with four Euromissile HOT missiles and a SFIM APX M397 stabilised sight.
- SA 342M1: SA 342M retrofitted with three Ecureuil main blades to improve performance.
- SA 349: Experimental aircraft, outfitted with stub wings.
|Capacity||up to 3 or 4 passengers|
||11.97 m (39 ft 3 in) including rotor|
|Height||3.15 m (10 ft 4 in) overall; 2.72 m (8 ft 11 in) to top of rotor hub|
|Main rotor diameter||10.5 m (34 ft 5 in)|
|Empty weight||917 kg (2,022 lb)|
|Max take off weight||1,800 kg (3,968 lb)|
|Maximum speed (Vne)||310 km/h (190 mph, 170 kn) at sea level|
|Cruising speed at sea level||264 km/h (164 mph, 143 kn) max cruise at sea level|
|Ascent speed at sea level||9 m/s (1,800 ft/min) max at sea level|
|Ceiling in service||5,000 m (16,000 ft)|
|Passable distance at sea level with standard reserve||233 km (145 mi; 126 nmi)|
|Powerplant||1 × Turbomeca Astazou IIIA turboshaft, 440 kW (590 hp)|
|Armament||Guns: 2x forward-firing 7.62 mm (0.300 in) machine-guns (optional)
Rockets: Matra or Brandt 2.75 in (70 mm) or 68 mm (2.7 in) rocket pods (optional)
Missiles: 4x AS.11 or 2x AS.12 wire-guided missiles; 4x or 6x Euromissile HOT (optional)
- UK Army – 26 in active.