Tag Archives: Turboméca Arriel 1A

24 January 1975

Aérospatiale SA 365 C Dauphin 2, F-WVKE. (Vertical Flight Society)

24 January 1975: First flight Aérospatiale SA 365 C Dauphin 2 prototype, F-WVKE, s/n 004. This prototype was built from a single engine SA 360 C Dauphin.

The SA 365 C is a single main rotor/fenestron twin-engine medium helicopter. It is operated by a single pilot seated in the right seat, and can carry a maximum of 13 passengers. The four-bladed articulated main rotor has a diameter of 11.68 meters (38.31 feet) and turns clockwise as seen from above. (The advancing blade is on the left.) A 0.89 meter (2.95 feet), 13-bladed fenestron provides anti-torque and yaw control.¹ In 1977, a Star Flex rigid rotor hub replaced the articulated main rotor.

The fuselage is 10.98 meters (36.02 feet) long, 3.17 meters (10.40 feet) wide and 3.27 meters (10.72 feet) high. In the original configuration, the Dauphin 2 had fixed wheeled landing gear. The second prototype was used to experiment with retractable tricycle gear, which was adopted with the SA 365 N.

Aérospatiale SA 365 C Dauphin 2, F-WVKE. (Vertical Flight Society)

The SA 365 C was powered by two Turboméca Arriel 1A turboshaft engines. These had a maximum continuous power rating of 430 kW (577 h.p.) @ 50,764 r.p.m.; 466 kW (625 h.p.) for take off (5-minute limit) @ 52,007 r.p.m./or one engine inoperative (30-minute limit); and 486 kW (652 h.p.) @ 52,680 r.p.m., one engine inoperative,  2½-minute limit.

The main rotor turns 350 r.p.m. (+/- 10) in normal operation. The minimum transient speed to 285 r.p.m., is allowed in case of engine failure, and 320–420 r.p.m. during autorotation.

The helicopter’s maximum mass is 3,400 kilograms (7,496 pounds, maximum gross weight). Its maximum speed (VNE)  is 315 kilometers per hour (170 knots), and maximum operating altitude, 4,572 meters (15,000 feet). Fuel capacity is 640 liters (3 liters are unusable).

Fifty SA 365 C and C1 helicopters were built before being replaced by the SA 365 N Dauphin.

¹ The ducted fenestron is more effective than a conventional tail rotor, provides less drag in forward flight, and is safer when operating near the ground.

© 2022, Bryan R. Swopes