Tag Archives: Societe nationale industrielle aérospatiale

27 June 1974

Aérospatiale AS 350 C Nº. 001, F-WVKH. during a test flight. (Airbus)

27 June 1974: Societe nationale industrielle aérospatiale (SNIAS) test pilot Daniel Bauchart and flight test engineer Bernard Certain took the first prototype Aérospatiale AS 350, F-WVKH, for a 40 minute first flight at at Marignane, France.

The AS 350 C, Nº. 001, was powered by a Lycoming LTS101-600A-1 turboshaft engine rated at 592 shaft horsepower. A second prototype, AS 350 B, F-WTNB, powered by a Turboméca Arriel engine, flew for the first time 14 February 1975.

Initially known internally as the “Business Allouette” after another SNIAS helicopter, the company eventually named the new helicopter Écureuil, which means “squirrel” in English. The name was announced publicly 9 March 1976. Helicopters for the North American market were called the “A-Star.”

Aérospatiale AS 350 C  F-WVKH. (Airbus)

The Aérospatiale AS 350 Écureuil is a  6–7 place, single-engine light helicopter, operated by a crew of one or two pilots. Introduced by Aérospatiale in 1978, it remains in production today and is one of the most popular civil helicopters, with more than 5,000 built. The manufacturer is now known as Airbus Helicopters. The current model is the Airbus H125 (previously named the Eurocopter AS 350 B3e)

The Lycoming LTS101-600A engine that powered the AS 350 C prototype and U.S.-production A-Stars is a turboshaft engine with a single stage axial-flow, single stage centrifugal-flow compressor section, and annular combustor, a single stage gas generator turbine and single stage free power turbine. The gas generator section (N1) turned 49,638 r.p.m, 5-minute limit for takeoff, and the power turbine (N2), 6,085 r.p.m. The -600A-2 is 0.786 meters (2 feet, 6.95 inches) long, 0.492 meters (1 foot, 7.37 inches) wide and 0.600 meters (1 foot, 11.62 inches)high. It weighs 115 kilograms (253.5 pounds).

The second prototype, the Turbomeca-powered AS 350 B, F-WTNB. (Airbus)

The AS 350 B3 is a high-performance variant, specially configured for high density altitude operations (“hot and high”). The overall length with rotors turning is 12.94 meters (42 feet, 5.4 inches). The fuselage is 10.93 meters (35 feet, 10.3 inches) long and the cabin is 1.87 meters (6 feet, 1.6 inches) wide. The helicopter’s overall height is 3.14 meters (10 feet, 3.6 inches).

In keeping with standard French practice, the Écureuil/A-Star’s main rotor system turns clockwise as seen from above. (The advancing blade is on the helicopter’s left side.) The composite hingeless three-blade rotor has a diameter of 10.69 meters (35 feet, 0.9 inch). The normal operating range is 385–394 r.p.m. (320–430 r.p.m. in autorotation). A two-bladed tail rotor is mounted on the right side of the tail boom in a pusher configuration. It rotates clockwise, as seen from the helicopter’s left. (The advancing blade is below the axis of rotation.) Its diameter is 1.86 meters (6 feet, 1.2 inches.)

The AS 350 B3 has an empty weight of approximately 1,174 kilograms (2,588 pounds), depending on installed equipment, and maximum gross weight of 2,250 kilograms (4,961 pounds).

AS 350 B3 three-view illustration with dimensions. (Eurocopter)

The AS 350 B3 variant is powered by a single Turboméca Arriel 2B turboshaft engine. The Arriel 2B is a free turbine turboshaft engine which uses an electronic engine control system (EECU). The engine has a two-stage compressor section (single-stage low-pressure axial flow, single-stage high-pressure centrifugal flow); an annular combustion chamber; and two-stage turbine section (single-stage gas generator and single-stage power turbine). The compressor section turns 52,110 r.p.m. at 100% N1; The power turbine, N2, turns 39,095 r.p.m. at 100%. A gear reduction unit reduces the engine’s output shaft speed to 5,990 r.p.m.

The Arriel 2B produces 847 shaft horsepower, but is de-rated to the helicopter’s main transmission limit. Installed, the Arriel 2B is rated at 536 horsepower for cruise; 700 horsepower, Maximum Continuous Power; and 733 horsepower for take off (5 minute limit).

The Arriel 2B is 118.0 centimeters (3 feet, 10.46 inches) long, 50.0 cm (1 foot, 6.69 inches) wide, 62.0 cm (2 feet, 0.41 inches) high. It weighs 134 kilograms (295.4 pounds), dry. The Arriel series engines are now produced by Safran Helicopter Engines.

The AS 350 B3 has a cruise speed of 132 knots (152 miles per hour/245 kilometers per hour) and maximum speed of 155 knots (178 miles per hour/287 kilometers per hour). It carries over four hours of fuel and has a maximum range of 357 nautical miles (411 statute miles/662 kilometers). The maximum allowable altitude is 7,010 meters (23,000 feet).

Turboméca-powered AS 350 B F-WTNB. Note the single horizontal stabilizer. (Airbus)

© 2019, Bryan R. Swopes

7 April 1967

SA 340 F-WOFH (Airbus Helicopters)
Jean Boulet hovers the prototype Sud-Aviation SA 340 Gazelle, 340.001, F-WOFH, at Marignane, France, 7 April 1967. (Airbus Helicopters)

7 April 1967: The prototype Sud-Aviation SA 340 Gazelle, c/n 340.001, F-WOFH, made its first flight at Marseille–Marignane Airport with test pilot Jean Boulet. The SA 340 was a five-place, light turboshaft-powered helicopter, flown by a single pilot. It was intended as a replacement for the SA 313B/318C Alouette II and SA 316/319 Alouette III.

The prototype used the engine, drive train, tail rotor and landing skids of an Alouette II, and a new three-bladed, composite, semi-rigid main rotor, based on the four-bladed rigid rotor of the Messerschmitt-Bölkow-Blohm (MBB) Bo-105.

Sud-Aviation test pilot Jean Boulet in the cockpit of the SA 349, an experimental variant of the SA 340 Gazelle.
Sud-Aviation test pilot Jean Boulet in the cockpit of the SA 349, an experimental modification of the prototype SA 340 Gazelle, 340.001. (Airbus Helicopters)

Société nationale des constructions aéronautiques du sud-ouest (Sud-Aviation) was a French government-owned aircraft manufacturer, resulting from the merger of Société nationale des constructions aéronautiques du sud-est (SNCASE) and Société nationale des constructions aéronautiques du sud-ouest (SNCASO) in 1957. In 1970, following another merger, the company would become Société nationale industrielle aérospatiale, or SNIAS, better known as Aérospatiale. This company combined several other manufacturers such as Matra and Messerschmitt-Bölkow-Blohm to become Eurocopter, then EADS. It is now Airbus Helicopters.

The SA 340 was powered by a Turboméca Astazou IIN turboshaft which turns 42,500 r.p.m. (± 200 r.p.m.). The output shaft speed is reduced through a 7.34728:1 gear reduction.  The engine rated at 353 kW (473 shaft horsepower) continuous, or 390 kW (523 shaft horsepower) for takeoff. It is temperature-limited to 500 °C. for continuous operation, or 525 °C. for takeoff.

The main rotor assembly, mast, transmission and Turbomeca Astazou engine of the prototype SA 340 Gazelle. (Airbus Helicopters)
The main rotor assembly, mast, swash plate and pitch control links, transmission, main driveshaft and Turboméca Astazou turboshaft engine of the prototype Sud-Aviation SA 340 Gazelle, F-WOFH. (Airbus Helicopters)

F-WOFH was used to test the new fenestron anti-torque system. The conventional tail rotor was replaced with a smaller 13-bladed ducted fan contained within a large vertical fin. The fenestron had several advantages: It was safer, as it was protected from ground strikes or from ground personnel walking into it. It was more effective in producing thrust for anti-torque, though it required more engine power at a hover. It reduced the aerodynamic drag of the helicopter in forward flight, and was not subject to large displacements resulting from dissymmetry of lift. The large fin was cambered and relieved the anti-torque system during forward flight. This meant that the  helicopter could be flown following an anti-torque failure, rather than requiring an immediate emergency autorotation.

Sud-Aviation fenestron on an early production SA 341 Gazelle, c/n 1006, F-WTNV
Sud-Aviation fenestron on an early production SA 341 Gazelle, c/n 1006, F-WTNV. (Airbus Helicopters)

The Aérospatiale SA 341 Gazelle entered production in 1971, as both a military and civil helicopter. The aircraft was also produced in England by Westland.

The Gazelle the first helicopter to be certified for instrument flight with a single pilot.

The SA 341 had an overall length, with rotors turning, of 11.972 meters (39 feet, 3.34 inches). The fuselage was 9.533 meters (31 feet, 3.31 inches) long and the top of its fin was 3.192 meters (10 feet, 5.67 inches) high. The three-bladed main rotor was 10,500 meters (34 feet, 5.39 inches) in diameter, and turned clockwise as seen from above. (The advancing blade is on the left.) The rotor has a normal operating speed of  378 r.p.m., ± 12 r.p.m. (310–430 r.p.m. in autorotation. The 13-blade fenestron is enclosed in a duct in the vertical fin. The rotor has a diameter of 0.695 meters (2 feet, 3. 36 inches) and turns counter-clockwise as seen from the left. (The advancing blades are above the axis of rotation.)

The helicopter’s certified maximum gross weight is 1,800 kilograms, or 3,970 pounds.

Aérospatiale SA 341 Gazelle three-view illustration with dimensions. (Aérospatiale)

The Gazelle is powered by a Turboméca Astazou III.

Teh SA 341 has a maximum speed (Vne ) of 310 kilometers per hour (168 knots ) at Sea Level, making it the fastest light helicopter produced at the time. The helicopter is limited to a pressure altitude of 20,000 feet (6,096 meters). It can operate in temperatures from -50  to +45 °C. (-58 to 113 °F.)

Approximately 1,775 Gazelles were built between 1967 and 1996, when production ended.

Sud-Aviation SA 340.001, F-WOFH. (Airbus Helicopters)
Sud-Aviation SA 340.001, F-WOFH. (Airbus Helicopters)

© 2019, Bryan R. Swopes

17 March 1969

SNCASE SA 315A 001 (Airbus Helicopters)

17 March 1969: First flight, Société nationale des constructions aéronautiques du Sud-Est test pilot Roland Coffignot and flight engineer Gérard Boutin made the first flight of the prototype SA 315A Lama, serial number 315-001. The new helicopter combined the airframe of the SNCASE Alouette II with the drive train and rotors of the Alouette III.

The helicopter was built to meet the specific needs of the Indian Air Force for operations in the Himalayan Mountains. It was required to take off and land at an altitude of 6,000 meters (19,685 feet) while carrying a pilot, one passenger and 200 kilograms (441 pounds) of cargo. The SA 315A was able to exceed this, landing and taking off in the Karakoram Mountains at 6,858 meters (22,500 feet).

315-001 was later upgraded to the SA 315 B configuration. It was registered F-BPXS. On 19 June 1972, Aérospatiale Chief Test Pilot Jean Boulet with Gérard Boutin set a Fédération Aéronautique Internationale (FAI) World Record for Altitude Without Payload at 10,836 meters (35,551 feet).¹ Three days later, 21 June, Boulet set another three World Records by flying 315-001 to an altitude of 12,442 meters (40,820 feet).²

SNCASE SA 315 B 001. (Airbus Helicopters)

The SA 315 B Lama is a 5-place light helicopter powered by a turboshaft engine. It is operated by a single pilot. The fuselage is 10.236 meters (33 feet, 7.0 inches) long. With rotors turning, the helicopter has an overall length of 12.919 meters (42 feet, 4.6 inches) and height of 3.090 meters (10 feet, 1.7 inches). The SA 315 B has an empty weight of 1,021 kilograms (2,251 pounds) and a maximum gross weight of 1,950 kilograms (4,300 pounds). With an external load carried on its cargo hook, the allowable maximum gross weight is 2,300 kilograms (5,070 pounds).

Aérospatiale SA 315 B Lama three-view illustration with dimensions. (Aérospatiale Hélicoptères)

The three-bladed, fully-articulated main rotor has a diameter of 11.020 meters (36 feet, 1.9 inches). It turns clockwise, as seen from above. (The advancing blade is on the left side of the helicopter.) Normal main rotor speed, NR, is 350–360 r.p.m. The range in autorotation ins 270–420 r.p.m. The three-bladed anti-torque tail rotor is mounted on the left side of the tail boom in pusher configuration. It is 1.912 meters (6 feet, 3.3 inches) in diameter and turns clockwise, as seen from the helicopter’s left side. (The advancing blade is below the axis of rotation.) It turns at 2,020 r.p.m.

Aérospatiale SA 315 B Lama F-BPXS, s/n 315-001, lifting an external load on its cargo hook, 1980. (Kenneth Swartz)

The Lama was initially powered by a Societé Anonyme Turboméca Artouste III B (later aircraft, Artouste III B1) turboshaft engine. This is a single-shaft engine with a single-stage axial-flow, single-stage centrifugal flow, compressor section and a three-stage turbine. The engine turns 33,500 r.p.m. and the output drive shaft turns 5,773 r.p.m. The Artouste III B1 produces a maximum 870 horsepower, but is derated to 570 horsepower for installation in the Lama. The engine is 1.815 meters (5 feet, 11.5 inches) long, 0.667 meters (2 feet, 2.3 inches) high and 0.520 meters (1 foot, 8.5 inches) wide. It weighs 178 kilograms (392 pounds).

The helicopter has a cruise speed 98 knots (113 miles per hour/181 kilometers per hour) and a maximum speed (VNE) of 113 knots (130 miles per hour/209 kilometers per hour) at Sea Level. Sideward or rearward flight (or operations in crosswinds or tailwinds) are restricted to 18 knots. The maximum operating altitude is 7,000 meters (22,966 feet). At 1,950 kilograms (4,299 pounds), the Lama has a hover ceiling in ground effect (HIGE) of 5,050 meters (16,568 feet), and out of ground effect (HOGE), 4,600 meters (15,092 feet).

Société nationale des constructions aéronautiques du Sud-Est became Societe nationale industrielle aérospatiale (SNIAS) in 1970. The company produced the SA 315 B Lama beginning in 1971. It was also built under license by Hindustan Aeronautics in India and Helibras in Brazil.

The total number of SA 315 Bs and its variants built is uncertain. In 2010, Eurocopter, the successor to Aérospatiale, announced that it will withdraw the Lama’s Type Certificate in 2020.

An Aérospatiale SA 315 B Lama “On Top of the World” ( © Phillipe Fragnol)

¹ FAI Record File Number 788.

² FAI Record File Numbers 753, 754 and 11657.

© 2019 Bryan R. Swopes