Charles M. Olmsted, a European trained physicist from Upstate New York, had an interest in flight from his early years. His success with gliders in the 1890's led to the formation of the Buffalo-Pitts-Olmsted Syndicate in 1910 to develop aircraft. Following failure of the related agricultural equipment manufacturing company, Olmsted formed the CMO Physical Laboratory, continuing to manufacture and sell his ultra-efficient propellers. Olmsted designs differed from other propellers, having a large surface near the blade base and very little surface at the tip. Olmsted's propellers represented a fundamental difference in design philosophy that has not been duplicated by any other designer.
This left-turning pusher propeller won a test against a Curtiss propeller on a Curtiss Flying Boat owned by famous industrialist Harold McCormick of International Harvester. The Olmsted propelled aircraft broke 1914 records for worldwide hydroplane airspeed, as well as for payloads of worldwide hydroplanes and all US planes, lifting 999 kg (2200 lbs), including six passengers.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.