Public domain
Production. Airplane propellers. Frank Geary uses an electro-limit gauge at a Hartford, Connecticut, plant to make final inspections of a three-way hydromatic spider that form part of the mechanism which varies the pitch of airplane propeller blades while planes are in action. At this plant propelle
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Credit lineProduction. Airplane propellers. Frank Geary uses an electro-limit gauge at a Hartford, Connecticut, plant to make final inspections of a three-way hydromatic spider that form part of the mechanism wh. 1942-01-01. United States. Office Of War Information, Feininger, Andreas. Farm Security Administration/Office of War Information Collection, Library of Congress. Public domain.