Public domain
Mitchell Field. "Plumbing system" of a fighting plane. The rear end of an air-cooled aviation engine with cowling removed, showing fuel lines, ignition leads, instrument leads and other intimate portions of the anatomy of a mighty flying power plant
From the collection of Library of Congress. Free to download, adapt and use — no permission needed.
Credit lineMitchell Field. "Plumbing system" of a fighting plane. The rear end of an air-cooled aviation engine with cowling removed, showing fuel lines, ignition leads, instrument leads and other intimate porti. 1942-01-01. United States. Office For Emergency Management, Palmer, Alfred T.. Farm Security Administration/Office of War Information Collection, Library of Congress. Public domain.