31st of July 1951
It was on this day in aviation history that the experimental SNCASE SE.3120 Alouette helicopter made its first flight.
SNCASE SE.3120 Alouette
The SE.3120 was developed at the same time as the SE.3110 helicopter. Although they didn't look the same they shared a large commonality in the dynamic components. An obvious difference was the tail rotor configuration. The SE3110 had a complicated angeled dual tail rotor, while the SE.3120 had a more 'conventional' single tail rotor. SE.3110
The SE.3120 had a bubble-like canopy with place for a pilot and two passengers. Aft of the cockpit the fuselage was an open framework structure. It was powered by a Salmson 9NH air-cooled 9 cylinder radial engine, delivering 200 hp (150 kW) During the different test flights, the helicopter was tested with a tricycle landing gear and a skid undercarriage.
Two prototypes were built and tested. It was during one of the test flights that one of the test pilots (Jean Boulet) set a closed-circuit distance record for this class of helicopter, 675 nm (1250 km). This impressive record could not save the project. The aircraft proved to require a lot of maintenance and the progress made in the development of the (unrelated) jet engine powered Alouette II resulted in the SE.3120 program being abandoned.
General specifications of the SE.3120
Capacity: 2 passengers
Length: 10.45 m (34 ft 3 in)
Height: 2.90 m (9 ft 6 in)
Empty weight: 750 kg (1,653 lb)
Gross weight: 1,250 kg (2,756 lb)
Powerplant: 1 × Salmson 9NH 9-cylinder air-cooled radial engine, 150 kW (200 hp)
Main rotor diameter: 11.60 m (38 ft 1 in)
Main rotor area: 105.7 m2 (1,138 sq ft)
Maximum speed: 201 km/h (125 mph, 109 kn)
Endurance: 2 1⁄4 hr
Service ceiling: 4,000 m (13,000 ft)
Rate of climb: 4.50 m/s (885 ft/min)