An early predominant manufacturer in the United States, Spencer Heath's American Propeller and Manufacturing Company was first to use machines for mass production of aircraft propellers, and, under the Paragon trademark, these were widely used in World War I. Construction was a wood laminate because of light weight, strength, fabrication ease, and resistance to fatigue in a vibrating and flexing environment.
Heath demonstrated the first "engine-powered, engine-controlled, variable and reversible pitch propeller" in 1919, but was unsuccessful in convincing the Army of the practicality of the concept. He sold the company to the Bendix Corporation in 1929 and retired from aeronautics two years later.
The artifact's shape indicates it is a Flexible Variable Pitch propeller. The manufacturer's brochure states: "These propellers are designed on the principle that the blade should constantly bend . . . accompanied by a torsional or twisting action by which the pitch would automatically change . . ."
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.
1914-1939
United States of America
PROPULSION-Propellers & Impellers
American Propeller and Manufacturing Company
Spencer Heath
Type: Two-Blade, Fixed-Pitch, Wood
Diameter: 251.5 cm (99 in.)
Chord: 24.1 cm (9.5 in.)
Engine Application: Curtiss OX-5, V-8, liquid cooled, 67 kW (90 hp)
Rotor/Propeller: 251.5 x 24.1 x 15.9 x 10.5cm (99 x 9 1/2 x 6 1/4 x 4 1/8 in.)
3-D: 251.5 x 22.4 x 10.8cm (99 x 8 13/16 x 4 1/4 in.)
Wood
Varnish
Paint
A19300032000
Gift of American Propeller & Manufacturing Co.
National Air and Space Museum
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