The Buhl "Pusher" Autogiro of 1931: A Critical Reappraisal

The first "pusher" Autogiro was created by Buhl Aircraft, the third licensee of the Autogiro Company of America (ACA)1 (the first was Pitcairn Aviation, a licensee of ACA's predecessor in interest the Pitcairn-Cierva Autogiro Company and the second was the Kellett brothers of Philadephia2) in March 1931. Buhl was a successful fixedwing manufacturer3 and part of a large financial, manufacturing and real estate organization headquartered in Detroit. The company was founded as the Buhl-Verville Aircraft Company in 1925 with Lawrence D. Buhl as President and A. H. Buhl as Vice President. Buhl was apparently well-financed and described itself in a letter of Geoffrey S. Childs of the ACA on March 23, 1931, as consisting of "members of the Buhl family [who] are all extremely wealthy individuals in addition to their holdings in the above mentioned [family] companies. This aircraft, briefly described by Peter W. Brooks, George Townson,4 et. al.5 as having been designed by the Buhl Autogiro design team consisting of chief engineer Etienne Dormoy, assistant chief engineer R. V. Doorn and nine other engineers in consultation with ACA engineers. While it has been asserted that the Buhl "pusher" design was influenced by Cierva's unbuilt patented6 design study for the C.21 of 1930,7 newly discovered evidence in the Pitcairn Archives clearly points to a more direct and earlier contribution by both Pitcairn and Cierva and strongly suggests that the "pusher" configuration had been conceived by November 16, 1929 and there is additional evidence of significant contributions of Pitcairn engineers, primarily Paul Stanley.1