The Béarn 6 was a six cylinder air-cooled piston aircraft engine produced in France in the late 1930s, 1940s and early 1950s.
Design and development
The Béarn 6 suffered from lack of development and was not a commercial success, most production engines had been removed from service by 1950 due to poor reliability.
6C
6D
6D-07
Dassault MD-303
Nord 2101 Norazur
Dewoitine HD.731
SFCA Lignel 16
S.C.A.N. 20
SNCASO SO.90
SNCASE SE-700A
S.N.C.A.C. NC.420
Data from Aircraft Engines of the World 1946
Type: 6 cylinder, air-cooled, inverted, in-line, geared, super-charged, 4-stroke piston engine
Bore: 130 mm (5.12 in)
Stroke: 135 mm (5.31 in)
Displacement: 10.7 l (653 cu in)
Length: 1,500 mm (59.06 in)
Width: 450 mm (17.72 in)
Height: 825 mm (32.48 in)
Dry weight: 290 kg (639.3 lb)
Frontal Area: 0.33 m2 (3.6 sq ft)
Valvetrain: 2 overhead valves per cylinder, pushrod actuated.
Supercharger: Gear driven 1-speed supercharger at 11.15:1 gear ratio.
Fuel system: 1x Zenith 80RGSL-05 updraught carburettor with automatic boost control
Fuel type: 87 Octane gasoline
Oil system: Pressure fed at 482.6 kPa (70 psi), dry sump
Cooling system: Air baffled
Reduction gear: Planetary reduction gear, 0.67:1 ratio adapted for Ratier or Chauvière variable-pitch propellers
Starter: Air Equipment 51020 electric inertia starter
Ignition: 2 x R.B. GPBA magnetos, 2 x spark plugs per cylinder fed by a shielded ignition harness.
Power output: Take-off:305.74 kW (410 hp) at 2,800rpm, 1,160 mm (45.67 in) / +3.58 kg (7.9 lb) boost with 100/130 octane gasoline
Normal:260.99 kW (350 hp) at 2,700rpm at 2,000 m (6,561.68 ft)
Cruising:193.88 kW (260 hp) at 2,200rpm at 2,000 m (6,561.68 ft)
Specific power: 27.89 kW/l (0.63 hp/cu.in)
Compression ratio: 7.2:1
Specific fuel consumption: 0.322 kg/kW/hr (0.53 lb/hp/hr)
Oil consumption: 0.00669 kg/kW/hr (0.011 lb/hp/hr)
Power-to-weight ratio: 0.968 kW/kg (0.585 hp/lb)
