Forest Edwards builds and flies scale model airplanes and engineers miniature engines.  He has won numerous awards for his scale airplanes, engines and flying skills. In the early 1980s, Edwards designed and developed this 5-cylinder radial engine to power his 1/4-scale Fleet model airplane, based on the 1930 Fleet Biplane. He received many requests to manufacture the engine, so between 1982 and 1994, Edwards produced 30 engines. Many were installed into model airplanes and some are still being flown today.

The 5-cylinder radial burns regular gasoline, incorporates a dry sump lubrication system and produces more than six horsepower. In his last few engines, Edwards added a centrifugal advance in the distributor and a crankshaft-driven supercharger for maximum performance.  Edwards’ engines are completely machined from 7075 aircraft-grade aluminum and are perhaps the most reliable model radial engines built to date.

Watch a video below showing how a radial engine works. The video was generated in a 3D drawing program called Autodesk Inventor. The cutaway view shows the pistons in action on a 7-cylinder radial engine so you can see how all the internal movements are related.

Exhibit added: May 1, 2008 - Last modified: June 14, 2023

Presented by The Joe Martin Foundation for Exceptional Craftsmanship