Aeromarine Plane & Motor Co. Ground-Adjustable-Pitch Propeller

Type: Two-Blade, Ground Adjustable, Metal

Diameter: 246 cm (97 in.)

Chord: 20 cm (7.9 in.)

Engine Application: Unknown

During 1908, New York entrepreneur Inglis M. Uppercu made an investment in New Jersey's Boland Aeroplane and Motor Co., eventually becoming its president and chairman. When its founder, Frank E. Boland, died in a 1913 aviation accident, Uppercu reorganized the firm in 1914, renaming it the Aeromarine Plane and Motor Co. He further developed the Boland designs and later contributed to the flying-boat design, with a military order enabling Aeromarine to begin mass production.

This ground-adjustable-pitch propeller was built by Uppercu in 1914. A pilot or mechanic could change the blade angle on the ground before a flight. It is an indirect precursor of the successful detachable-blade ground-adjustable pitch propellers of the mid-1920s pioneered by the U.S. Army and the Standard Steel Propeller Company. The particular cast aluminum design proved to be too weak for the stresses inflicted upon aerial propellers, with the fatigue strength being too low. There is no record if Uppercu continued experimentation with this type of propeller.