Cycloidal Propulsion Applied to Aircraft

After reporting observations on the flight of gulls which indicated that the wing top moves with a cycloidal motion, the author proceeds to an analysis of this type of motion as it might be applied to the propulsion of aircraft. Various aspects of cycloidal propellers, including their efficiency, are discussed, and their application to heavier-than-air and lighter-than-air craft is urged. The advantages of this method of propulsion are discussed. Tests of model and full-size propellers are referred to, but are not included in the paper.