Collection Item Summary:
Vereinigte Deutsche Metallwerke, or United German Metalworks, was a society of medium-sized family firms formed in 1930. One of VDM’s member companies, the Heddernheimer Metal Company, initiated the development of metal propellers in Germany by introducing a ground-adjustable propeller in the late 1920s, similar in construction to the American Standard Steel propeller.
VDM’s Dr. Hans Ebert later developed an ingenious method of pitch actuation using a reversible electric motor mounted on the engine crankcase. Actuation was via a flexible shaft connected to a small primary drive reduction gearbox, which was in turn attached to a large annular gearbox fitted to the rear of the propeller hub.
VDM constant-speed propellers appeared during the spring of 1937, and full-scale production was up and running a year later. VDM became the leading German manufacturer of metal propellers before and during World War II, utilized by approximately 90 percent of the Luftwaffe's front-line aircraft.