The Pratt & Whitney Hornet series occupies a significant place in the development of reliable and powerful engines for both commercial and military operators. The series began with the 1926 development of the air-cooled R-1690 for the U.S. military, and was Pratt & Whitney’s second major engine, following the Wasp, another 1926 development. This early version of the Hornet allowed the first practical torpedo plane, the Martin T4M which carried a 909 kg (2000 lb) torpedo for a range of 1079 km (665 miles).
First certificated in 1929, the R-1860-B was a larger version for use in civil and military aircraft in the United States and abroad. Pratt & Whitney manufactured this particular R-1860-B Hornet for the U.S. Army Air Corps in 1932. The engine is most closely associated with the Sikorsky S-40 and S-41B flying boats. Subsequently, Pratt & Whitney engines powered nearly every flying boat built by Sikorsky.
Display Status
This object is on display in Boeing Aviation Hangar at the Steven F. Udvar-Hazy Center in Chantilly, VA.
Object Details
Date
1932
Country of Origin
United States of America
Type
PROPULSION-Reciprocating & Rotary
Designer
George Willgoos
Manufacturer
Pratt & Whitney
Physical Description
Type: Reciprocating, 9 cylinders, radial, air-cooled
Power rating: 429 kW (575 hp) at 1,950 rpm
Displacement: 30.5 L (1,860 cu in.)
Bore and Stroke: 159 mm (6.3 in.) x 171 mm (6.8 in.)
Weight: 377 kg (831 lb)
Dimensions
Diameter 144.6 cm (56.93 in.), Length 113.7 cm (44.78 in.)
Inventory Number
A19660390000
Credit Line
Found in the collection
Data Source
National Air and Space Museum
Restrictions & Rights
Usage conditions apply
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