Begun in 1925 by former Wright Aeronautical employees as a spinoff from a machine tool company, Pratt & Whitney became one of the world’s largest manufacturers of aircraft engines, and the Wasp Jr. is one of the most successful reciprocating engines ever built. Pratt & Whitney introduced it as a complement to the highly successful Wasp and Hornet families of engines in 1930. The Wasp Jr. was essentially a Wasp of reduced dimensions. Pratt & Whitney and its licensees manufactured over 39,000 versions of the R-985 until 1953 for a wide variety of military and commercial aircraft, including light transports, trainers, sport aircraft, and helicopters.

The R-985-AN-14B powered the McDonnell XHJH-1 and XHJD-1 Whirlaway helicopters and the Avro Anson V trainer. This Wasp Jr.-aptly nicknamed "The Dancing Engine"- has been sectionalized and motorized to demonstrate the movements of its internal components.

Display Status

This object is on display in Boeing Aviation Hangar at the Steven F. Udvar-Hazy Center in Chantilly, VA.

Boeing Aviation Hangar

Object Details

Date

1942

Country of Origin

United States of America

Type

PROPULSION-Reciprocating & Rotary

Manufacturer

Pratt & Whitney

Physical Description

Type: Reciprocating, Radial, 9 cylinders, air cooled
Power rating: 336 kW (450 hp) at 2,300 rpm
Displacement: 16.1 L (985 cu in)
Bore and Stroke: 132 mm (5.2in.) x 132 mm (5.2 in.)
Weight: 309 kg (682 lb)

Dimensions

Height: 117.5 cm (46.25 in.), Width: 117.5 cm (46.25 in.), Depth: 109.4 cm (43.06 in.)

Materials

Overall - aluminum and steel.

Inventory Number

A19761858000

Credit Line

Transferred from the Naval Aviation Museum

Data Source

National Air and Space Museum

Restrictions & Rights

Open Access (CCO)
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