Frank Piasecki

American aerospace engineer (1919–2008)

Frank Piasecki ( pee-ə-SEK-ee; Polish: [pjaˈsɛtski]; October 24, 1919 – February 11, 2008) was an American engineer and helicopter aviation pioneer. Piasecki pioneered tandem rotor helicopter designs and created the compound helicopter concept of vectored thrust using a ducted propeller.