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Rex W. Maneval

Photograph of Rex Maneval's helicopter

Inventor.  Born: April 30, 1890, Centralia, Kansas.  Died: December 1974, Frankfort, Kansas.

Rex W. Maneval of Frankfort was a man ahead of his time, among his projects was a helicopter that was designed in 1939.

As a child in Centralia, Maneval dreamed of becoming a mechanical engineer, but his parents preferred a business career and enrolled him in a business school in Kansas City to learn the fundamentals of banking. His banking career took him to banks in Centralia and Topeka and to the First National Bank in Frankfort which he managed. Engineering remained an obsession, however, and he found an outlet for his mechanical interests by extensive reading on the subject, and by endless experimenting with machines.

In the early 1920s he developed a highly successful chick hatching machine. He subsequently resigned his bank position in 1926 and opened his own hatchery in Frankfort, Kansas. Maneval Chickeries became one of the largest hatcheries in the state. In the early 1940s he acquired a locker plant and ice-cream store.

Tragedy struck Maneval in 1935 when his wife and son died of carbon monoxide poisoning. As a means of coping with his grief, he immersed himself in a new-found interest--aviation.  Among Maneval's projects was a helicopter which he designed in 1939, the same year Igor Sikorsky designed the VS-300 which eventually became the first successful commercial helicopter.

Several innovations were incorporated into Maneval's design. To neutralize torque, he used a pair of counter-rotating blades on a single shaft. The counter-rotating blades rendered unnecessary the single tail rotor, the conventional method of controlling torque. Eliminating the tail rotor results in a reduction in drag. A clever coaxial gearbox designed by Maneval made his counter-rotating blade system possible. Completed in 1941, Maneval's helicopter was flown several times over the years while tethered to the ground, but due to problems with excessive vibration, Maneval eventually scrapped the idea and stored the helicopter in one of his old hatcheries in 1974, when he donated it to the Kansas Historical Society.

Retiring from his hatchery firm in 1947, Maneval sold the locker plant and ice-cream store six years later to devote all of his time to the helicopter and other projects. In 1957 he designed, built, and tested a vertical-takeoff-and-landing (VTOL) craft which later was destroyed by fire. In the mid-1960s he turned his attention to a high-speed passenger train, and by 1967 he had designed a low-slung, streamlined train with innovative flanges, couplings, and brakes. He included in his plans the provision for substituting a jet-turbine engine as future technology increased the feasibility of a non-piston engine. Although he attempted to secure a patent and acceptance of his proposal by railroads and manufacturers, he was rejected by both the Patent Office and the rail industry. He then invented a jet-powered helicopter and completed drawings and a jet engine prior to his death in December, 1974.

In the 1980s, the Sikorsky Aircraft Company, the world's leading helicopter manufacturer, worked to develop the ultimate helicopter. Ironically, the company's design relied on counter-rotating blades using a system very similar to the one employed by Maneval in 1939. This is fitting testimony to the genius of a man, who with a staff of one and nothing but a converted hatchery for a shop, produced an idea that 40 years later would be incorporated into the most sophisticated aircraft design.

Entry: Maneval, Rex W.

Author: Kansas Historical Society

Author information: The Kansas Historical Society is a state agency charged with actively safeguarding and sharing the state's history.

Date Created: June 2003

Date Modified: January 2013

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