Aviation Pioneer. One of the three principal developers, along with Igor Sikorsky and Arthur Young, of rotary aviation. He is best remembered for his invention of the world's first twin rotor helicopter. The child of Polish immigrants, he was raised in Philadelphia and built model planes from early childhood. In his teens he worked for a company making the 'autogyro', a fixed wing craft with a rotor on top, then studied engineering at the University of Pennsylvania before transferring to New York University from which he graduated in 1940. That same year he partnered with Harold Venzie to found PV Engineering Forum and began designing the PV-2, an early single seat helicopter which he piloted on its maiden flight April 11, 1943. Mr. Piasecki sold his creation to the government then initiated work on the XHRP-X, the 48 foot tandem rotor craft that first flew in 1945. Called the "Flying Banana", it was capable of carrying 10 soldiers or 6,000 pounds of cargo and paved the way for the modern Chinook, long the work horse of military aviation. After the war he started Piasecki Helicopter then in 1955 Piasecki Aircraft and over the years made several developments, notably the PA-59K/VZ-8P Flying Geep, an Army troop transport that first flew in 1962 but was ultimately not deployed and the high speed 16H-1 Pathfinder, the first shaft-driven compound helicopter which was developed for the Army in the early 1960s. In the early 1980s he was responsible for creating the PA 97 Helistat, a hybrid craft built for the U.S. Forestry Service which consisted of four H-34J helicopters mounted beneath the million cubic foot bag of a ZPG-2W Navy Blimp. Constructed under the day-to-day supervision of legendary Naval Aviator Charlie Mills in a World War II era hangar at Lakehurst, New Jersey, site of the 1937 Hindenburg crash, the Heilstat flew for the first time on April 26, 1986, and crashed on July 1st. of that year killing one of the pilots. Mr. Piasecki received many honors including the Franklin Institute's 1979 Philip H. Ward Medal, the National Medal of Technology which was presented to him by President Reagan in 1986, and in 2005 the Smithsonian National Air and Space Museum Lifetime Achievement Award. He flew his own plane until he was well along in years, lived out his days in the Philadelphia suburbs, and died of cardiovascular disease. Explaining the need for his innovations he said: "An airplane must have landing fields, a truck needs roads, a train has to have tracks. Even a ship needs wharves and channels. But a helicopter, all a helicopter needs is a clearing."