| R-680 | |
|---|---|
| |
| Lycoming R-680 | |
| Type | Piston aero-engine |
| National origin | United States |
| Manufacturer | Lycoming Engines |
| First run | 1929 |
| Major applications | Beechcraft AT-10 Wichita Stinson Reliant Curtiss-Wright AT-9 Stinson Airliner |
| Produced | 1930-1945 out of production |
| Number built | over 26.000 |
The Lycoming R-680 is a nine-cylinder air-cooled radial engine, the first aero engine produced by Lycoming. The engine was produced in two types, the E and B series; both are essentially the same. The B4E was available in a trainer version with a front exhaust collector "ring" for use without cylinder air baffles. R-680 received Approved Type Certificate No. 42 on 4 Feb 1930.
Variants
- R-680
- Rated at 210 hp (160 kW) at 2,000 rpm.
- R-680B4Erpm
- Rated at 225 hp (168 kW) at 2,100 rpm.
- R-680BA
- Rated at 240 hp (180 kW)
- R-680E3A
- Rated at 285 hp (213 kW) at 2,200 rpm.
- R-680-6
- Rated at 245 hp (183 kW)
- R-680-9
- Rated at 300 hp (220 kW) at 2,200 rpm.
- R-680-13
- Rated at 300 hp (220 kW) at 2,200 rpm.
Applications
- Beech AT-10 Wichita
- Boeing-Stearman PT-13
- Cessna AT-8/AT-17
- Curtiss-Wright AT-9
- Fleetwings BQ-2
- Spartan NP-1
- Stinson Airliner
- Stinson Reliant
- Stinson L-1 Vigilant
- Waco S Series
Specifications (R-680-E3A)
Data from Jane's Fighting Aircraft of World War II.
General characteristics
- Type: Nine cylinder air-cooled radial
- Bore: 4 5⁄8 in (117 mm)
- Stroke: 4 1⁄2 in (114 mm)
- Displacement: 680 in³ (11.15 litres)
- Length: 37.5 in (953.1 mm)
- Diameter: 43.5 in (1104 mm)
- Dry weight: 515.46 lb (233.9 kg)
Components
- Valvetrain: One inlet and one exhaust valve per cylinder at 30 degrees.
- Fuel system: single-barrel carburetor
- Fuel type: 87 octane rating gasoline
- Oil system: Full pressure type
- Cooling system: Air-cooled
Performance
- Power output: 330 hp (246 kW) at 2,300 rpm at sea level
- Compression ratio: 7:1
- Power-to-weight ratio: 0.64 hp/lb (1.05 kW/kg)
See also
Comparable engines
Related lists
References
Notes
Bibliography
- Bridgman, Leonard (1988). Jane's Fighting Aircraft of World War II. New York: Crescent Books. ISBN 0-517-67964-7.
| Lycoming aircraft engines | |
|---|---|
| Opposed piston engines | |
| Radial engines and H engines | |
| Aircraft diesel engines | |
| Turbofans | |
| Turboprops/Turboshafts | |
| Aero-derivative marine gas turbines | |
| Joint development | Avco (Lycoming)/Pratt & Whitney: T800-APW (Turboshaft) |
| See also | |