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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.

This propeller was thought to be used on the Army's first airship, a Curtiss-Baldwin of 1908.

 Display Status

This object is on display in Early Flight at the National Air and Space Museum in Washington, DC.

Early Flight
Object Details
Date 1908 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: 335.3 cm (132 in.) Chord: 35.6 cm (14 in.) Engine Application: Curtiss, 17.9 kw (24-hp), 4-cyclinder, water-cooled Dimensions Rotor/Propeller: 335.3 x 35.6 x 17.1 x 1cm (11 ft. x 14 in. x 6 3/4 in. x 3/8 in.)
 Materials Wood
 Inventory Number A19490047000 Credit Line Gift of Mr. Gould Dietz Data Source National Air and Space Museum Restrictions & Rights Open Access (CCO)
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