Lycoming began as a subsidiary of the Auburn Auto Company, and the R-680 was a development version of its first 138 kW (185 hp) aircraft engine. It was one of a number of engines designed to replace the ubiquitous Curtiss OX-5 following World War I. The R-680 was type certificated in early-1930, and originally rated at 157 kW (210 shp). Considered a very reliable engine, more than 26,000 were built before production ended following World War II.

The R-680 powered the Stearman PT-13 primary American military trainer during the 1930s and 1940s, for which more than 2,000 engines were built. This model R-680-9 was an Army Air Forces engine that powered the Stinson L-1 and L-12, Curtiss AT-9/A, Beech AT-10, Stearman PT-9B, and Stinson CQ-2 aircraft.

Display Status

This object is not on display at the National Air and Space Museum. It is either on loan or in storage.

Object Details

Date

Circa 1940

Country of Origin

United States of America

Type

PROPULSION-Reciprocating & Rotary

Manufacturer

Lycoming (Williamsport, Pennsylvania)

Physical Description

Type: Reciprocating, 9 cylinders, radial, air-cooled
Power rating: 220 kW (295 hp) at 2,300 rpm
Displacement: 11.1 L (680 cu in)
Bore and Stroke: 117 mm (4.6 in.) X 114 mm (4.5 in.)
Weight: 248 kg (547 lb)

Dimensions

Approximate: 99.1 × 109.2 × 109.2cm (39 × 43 × 43 in.)
Storage: 134.6 × 132.7 × 162.6cm (53 in. × 52 1/4 in. × 64 in.)
Overall: 547lb. (248.1kg)
Other: 43 1/4 x 37 1/2in. (109.9 x 95.3cm)

Materials

Magnesium Alloy
Steel
Aluminum
Stainless Steel
Copper Alloy
Rubber
Paint
Phenolic Resin
Natural Fabric
Paper

Inventory Number

A19860279000

Credit Line

Gift of San Jose State University

Data Source

National Air and Space Museum

Restrictions & Rights

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