The son of a Polish immigrant tailor, Piasecki was born in Philadelphia in 1919, he studied mechanical engineering at Pennsylvania University and by the age of 20 had gained an engineering degree from the Guggenheim school of aeronautics at New York University. With help from a few friends he then started a small company, the PV Engineering Forum, in the Philadelphia suburbs, which enabled him to build and, in April 1943, test-fly a single-person, single-rotor helicopter, designated the PV-2. At that stage, he had it in mind to satisfy what he thought would become a growing market of rich, individual customers.
Soon, however, he was exploring the twin-rotor concept, most successfully in 1945 with the PV-3 Dogship, which had 10 seats. The US navy, under wartime pressure from Congress to develop this new technology, gave Piasecki a contract, and within 13 months he had built and flown the navy's first helicopter, designated the HRP-1. These aircraft were nicknamed "flying bananas" because of the upward angle of the aft fuselage, designed to ensure that the forward and rear rotors did not collide.
When the second world war ended, Piasecki formed the Piasecki Helicopter Corporation, designating himself chief executive, chief engineer and chief test pilot. In addition to building helicopters for the US navy, air force and marine corps, he exported the models to the Royal Canadian air force, the French navy and the West German defence force. In 1953 he designed the world's first twin-turbine helicopter, the YH-16, capable of carrying a payload of 40 passengers. His tandem rotor technology led to the development of the CH-46 Sea Knight and the CH-40 Chinook, which played a critical role in Vietnam and all major conflicts after it.
In 1955, preferring to continue research and development, Piasecki left his own company, which was renamed the Vertol Aircraft Corporation - taking its title from the acronym for Vertical Take-Off and Landing. In its turn, this company was bought by Boeing in 1960 and became the Boeing helicopter division in 1987. Meanwhile, Piasecki reformed his company as the Piasecki Aircraft Corporation, "pioneers in vertical flight", which has continued to work on advanced helicopter technology, improved survivability and reduced operational costs. One of its most ambitious projects was what Piasecki called the "world's largest aircraft", which aimed to use four modified helicopters and a helium airship to carry exceptionally heavy loads.
In 1986 President Ronald Reagan awarded Piasecki the US's highest technical honour, the National Medal of Technology, and when the Berlin wall fell in 1989, President George Bush Sr asked him to return to his country of origin to help Poland re-establish its aircraft industry. In 2005, he received the Smithsonian National Air and Space Museum lifetime achievement award. Some of his early helicopter designs are displayed in the museum.
Known as Pi to his friends and staff, Piasecki was a demanding and occasionally table-thumping boss, but knew all his staff personally, and admired those who stood up to him. He had continued as chief executive, his mental abilities undiminished despite several disabling strokes.
