The Enfield Cycle Company manufactured during World War II an 80 watt generator powered by a 15cc engine. The idea was that the generator could be dropped by airplane to charge batteries of stranded vehicles with dead batteries. It was designed by Edgar Westbury, a pioneer of the use of internal combustion engines for model use. This page has photos of a surviving unit and links to an article by Westbury. In it he claims the engine was top secret and even 14 years after the war he was not allowed to discuss in detail applications of the engine. Check the badge on the engine it reads "Manufactured by the E.C.C." (Enfield Cycle Co.).