Frank N. Piasecki.

Rotary-wing aircraft technology was still in its infancy during World War II. One of the few development contracts issued during the war went to Piasecki Helicopter Corp., led by Frank N. Piasecki. However, the aircraft wouldn 't become ubiquitous on battlefields until long after the war ended. In this article in the May-June 1949 issue of Ordnance, "What about the Helicopter? It Brings New Concepts to Old Problems of Flight," Piasecki makes a case for the technology.

In 1939, Igor Sikorsky flew the VS-300. Powered by a 70-horsepower engine with a single main rotor and tail antitorque rotor, this was the first American helicopter to fly successfully in the United States.

From then on the entire American rotary-wing field began to "sprout its blades" and many different design configurations began to appear--and fly successfully. The laterally displaced double-rotored Platt-Lepage helicopter flew in 1941; the Kellett "Syncopter" incorporating intermeshing blades flew in 1944; Piasecki's twin tandem-rotored transport helicopter, capable of transporting a ton of useful load or 12 persons, was demonstrated successfully in 1945--his second successful helicopter design; Bendix's coaxially designed helicopter flew in 1946; and McDonnell's jet-powered "flying bike" performed satisfactorily for the U.S. Air Force in 1947.

Other American helicopters using various configurations include the Bell, Firestone, Hiller, Landgraf, De Lackner, Pentecost, Brantly, Kaman, Seibel, and Teicher-Hunt. Some of the more prominent foreign makes at present are the Bristol, Fairey, Cierva-Weir, Francais du Gyroplane, Breguet, Doblhoff, Focke-Achgelis, and the Russian Omega helicopter.

Few people are able to appreciate fully the great scientific achievement of controlled flight with a speed range from zero to 125 miles an hour. But many people are beginning to realize the growing list of uses, both military and civilian, for the helicopter. Much is expected from this rotary-wing machine that flies backward and sideward...