Douglas Light Aero Engines: From Kingswood to Cathcart

摘要

Douglas engines will be well known among motorcycle enthusiasts, but the use of converted Douglas engines in light and ultralight aircraft has been rather less trumpeted. While those with a specific interest in such aircraft will certainly be aware of the Douglas contribution, I suspect that even they will be surprised by the number and extraordinary variety of aircraft so powered, as revealed in these pages. In his introduction the author exposes the myth that "all 'thirties flat-twin Douglases must be Sprites". He also clarifies the understanding of the term "horsepower" in the inter-war years, "when it was a classification of engine capacity for taxation purposes, as opposed to a measure of power output", and a "4 h.p. engine" was one of 600 c.c. displacement.