Several former engineers of the failed Franklin Automobile Company formed Air Cooled Motors Corporation of Syracuse, New York in 1935. Retaining the Franklin name, the new company produced a range of flat-4 and 6 cylinder aircraft engines. Head engineers Carl T. Doman and Edward S. Marks supervised the design of the Model 4AC-150 air-cooled, four-cylinder, horizontally-opposed engine that was announced early in 1938. Several models of this engine, rated at 30 and 37 kW (40 and 50 shp), were produced. The need for additional power to meet higher aircraft gross weight requirements, as well as faster climb and more speed, resulted in the higher powered Franklin 4AC-171. Certificated on August 1939, it powered the Piper J3F-65 and Taylorcraft BF-60 aircraft.
In 1975, the company disbanded and sold all rights to the Polish government, becoming part of PZL, an association of Polish aero and engine manufacturers. Following the 1989 fall of Communism, the firm became WSK PZL – Rzeszów.
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 1939
Country of Origin
United States of America
Type
PROPULSION-Reciprocating & Rotary
Manufacturer
Aircooled Motors Corporation (Franklin)
Physical Description
Type: Reciprocating, Horizontally-opposed, 4 cylinders, Air-cooled
Power rating: 45 kW (60 hp) at 2,350 rpm
Displacement: 2.8 L (171 cu in)
Bore and Stroke: 98 mm (3.875 in.) x 92 mm (3.625 in.)
Weight: 72.2 kg (159 lb)
Dimensions
Storage (Rehoused on metal pallet and stand): 127 × 119.4 × 94cm, 174.6kg (4 ft. 2 in. × 3 ft. 11 in. × 3 ft. 1 in., 385lb.)
Materials
HAZMAT: Cadmium Plating
Steel
Copper Alloy
Magnesium Alloy
Aluminum
Rubber
Ceramic
Plastic
Paint
Inventory Number
A19880409000
Credit Line
Exchange with the Cradle of Aviation Museum
Data Source
National Air and Space Museum
Restrictions & Rights
Usage conditions apply
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