Several former engineers of the failed Franklin Automobile Company formed Air Cooled Motors in 1935. By 1938 a range of flat-4 and 6 aircraft engines was being produced, retaining the Franklin name. This post-war product was the largest model. 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.
The Aircooled Motors (Franklin) XO-425-3 was a horizontally-opposed airplane engine with a reduction gear propeller shaft and a geared supercharger. Similar to the Aircooled Motors 0-405-9, it was a larger but lighter engine, with higher compression. While the specific airframe application of the experimental XO-425-3 is not known, the O-425-5 model powered the Convair L-13/A/B.
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 late 1940s
Country of Origin
United States of America
Type
PROPULSION-Reciprocating & Rotary
Manufacturer
Aircooled Motors Corporation (Franklin)
Physical Description
Type: Reciprocating, horizontally-opposed, 6 cylinders, Air-cooled
Power rating: 186 kW (250 hp) at 3,200 rpm
Displacement: 6.8 L (425 cu. in.)
Bore and Stroke: 121 mm (4.75 in) x 102 mm (4.00 in)
Weight: 213.2 kg (470 lb)
Dimensions
Storage (Rehoused on metal pallet and stand): 165.1 × 116.8 × 124.5cm, 371.9kg (5 ft. 5 in. × 3 ft. 10 in. × 4 ft. 1 in., 820lb.)
Materials
HAZMAT: Cadmium Plating
Aluminum
Paint
Steel
Plastic
Copper Alloy
Synthetic Fabric
Paper
Ink
Adhesive
Inventory Number
A19600106000
Credit Line
Transferred from the U.S. Air Force Central Museum
Data Source
National Air and Space Museum
Restrictions & Rights
Usage conditions apply
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