Pratt & Whitney R-2060
R-2060 Yellow Jacket from Pratt & Whitney (P & W) is the name of an experimental aircraft engine with 2060 cubic inch ( cubic inch ) capacity (33.78 liters), 1000 HP power and water cooling . It was developed for the US Army Air Corps in the early 1930s , but was never tested in aircraft or built in series.
The R-2060 was a four-stroke 20-cylinder in-line star engine with five cylinder banks of four cylinders each around the crankshaft . In contrast to the conventional single and multiple star motors from P & W, it was not air-cooled, but water-cooled. The one-piece, five- bearing crankshaft was bent four times. As with the in-line four - cylinder engine, the offset angles of the individual cranks were 0 °, 180 °, 180 °, 0 °. In this way, even ignition intervals were achieved (one ignition per 36 ° crankshaft revolution). In each cylinder bank an overhead ( OHC ) droveCamshaft on the valves. Each of the five camshafts was driven by a separate vertical shaft. All in all, the engine was a progressive design for the time.
Technical specifications
- water-cooled 20-cylinder in-line four-stroke engine (five cylinder banks of four cylinders each)
- Stroke: 5 inch (127 mm)
- Bore: 5.25 in (133.4 mm)
- Displacement: 2061.7 cubic inches ( cubic inches ) (33.78 liters)
- Achieved power: 735 kW (1000 PS ) at 3000 rpm without charging
- Projected power: 1103 kW (1500 PS) at 3300 rpm with charging
- specific power : 22 kW / l or 30 PS / l (without charging)
- Length: 1.78 m
- Diameter: 1.07 m
- Mass: 544 kg