For the last F3D World Chamionships we all rushed out and purchased Henry's latest F3D engine. It was a front intake, rear exhaust. all of our engine installations were inverted. We could not always practice on paved runways. We soon realised that this engine with the huge venturi was a very efficient vacuum cleaner. For sucking up dirt it had hoover beaten by miles.

Don, do not do it.

Ed S