Walter Sagitta
The Walter Sagitta was a Czechoslovakian, air-cooled, inverted V-12 engine that first ran in 1937. With a displacement of 18.4 litres (1,123 cu in), it produced up to 373 kW (550 hp) at 2,500 rpm.[1]
Variants
- Sagitta I-MR
- 550 hp (410 kW) at 2,500rpm at 2,500 m (8,202 ft) - rated height[2]
- Sagitta I-SR
- 535 hp (399 kW) at 2,500rpm at 3,800 m (12,467 ft) - rated height[2]
- Sagitta II R.C.
- Fully supercharged, 388 kW (520 hp).[3]
Applications
Specifications (Sagitta I-SR & I-MR)
Data from [2]
General characteristics
- Type: 12-cylinder inverted vee piston engine
- Bore: 118 mm (4.65 in)
- Stroke: 140 mm (5.51 in)
- Displacement: 18.372 l (1,121.1 cu in)
- Length: 1,914 mm (75.35 in)
- Width: 725 mm (28.54 in)
- Height: 796 mm (31.34 in)
- Dry weight: 372 kg (820 lb) - Direct drive, 385 kg (849 lb) - Geared 2:3
Components
- Valvetrain: enclosed push-rod operated rockers, two valves per cylinder closed by triple springs
- Supercharger: 8.7 times crankshaft speed - I-MR. 10.2 times crankshaft speed - I-SR
- Fuel system: Automatic boost and mixture control by a horizontal carburrettor
- Fuel type: 85 Octane Aviation Gasoline
- Oil system: Dry sump, one pressure pump and two scavenge pumps
- Cooling system: Air-cooled
Performance
- Power output:
- Take-off: 460 hp (343 kW) at 2,500rpm - I-SR, 560 hp (418 kW) at 2,500rpm - I-MR.
- Rated power: 535 hp (399 kW) at 2,500rpm at 3,800 m (12,467 ft) - I-SR, 550 hp (410 kW) at 2,500rpm at 2,300 m (7,546 ft) - I-MR
- Maximum power: 540 hp (403 kW) at 2,600rpm at 4,000 m (13,123 ft) - I-SR, 600 hp (447 kW) at 2,500rpm at 1,750 m (5,741 ft) - I-MR.
- Specific power: 24.29 kW/l (0.534 hp/in³)
- Compression ratio: 6.25:1
- Specific fuel consumption: 0.315 - 0.328 kg/kW/hr (0.525 - 0.548 lb/hp/hr)
- Oil consumption: 0.004 - 0.0067 kg/kW hr (0.0067 - 0.11 lb/hp hour)
- Power-to-weight ratio: 1.046 kW/kg (0.636 hp/lb)
See also
- Comparable engines
- Related lists
References
- Notes
- Bibliography
- Gunston, Bill. World Encyclopedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9