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An early predominant manufacturer in the United States, Spencer Heath's American Propeller and Manufacturing Company opened in Baltimore in 1909. Heath was first to use machines for mass production of aircraft propellers and, under the Paragon trademark, these were widely used in World War I. Like most propellers of that era, 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.

 Display Status This object is on display in the Early Flight at the National Air and Space Museum in Washington, DC Early Flight
Object Details
Date 1911 Country of Origin United States of America Type PROPULSION-Propellers & Impellers Manufacturer American Propeller and Manufacturing Company Physical Description Type: Two-Blade, Fixed-Pitch, Wood Diameter: 182.9 cm (72 in.) Chord: 28.6 cm (11.25 in.) Engine Application: Unknown Dimensions Rotor/Propeller: 182.9 x 28.6 x 15.2 x 1.1 x 0.5cm (72 x 11 1/4 x 6 x 7/16 x 3/16 in.)
 Materials Overall: Wood
 Inventory Number A19300067000 Credit Line Gift of Alden Hydraulic Laboratory, Worchester Polytechnic Institute Data Source National Air and Space Museum Restrictions & Rights Usage conditions apply
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