De Havilland Hydromatic Propellers: Notes for Pilots and Ground Staff
Middlesex: The De Havilland Aircraft Company. 2nd Edition. Hardcover. 16mo. [no date]. Navy buckram, 67pp. Illustrated, with [5] foldout sketches of propellers. Fine. Fast facts for instillation and adjustment, ground and flight operation, governing and pitch change for irregularities and maintenance. More
