Piasecki Aircraft Corporation (PiAC) was founded by American vertical flight pioneer Frank Piasecki to develop compound helicopters and other advanced rotorcraft after he was ousted from the leadership of his first company, Piasecki Helicopter which was renamed Vertol Corporation and later acquired by Boeing.
In 2005, the company was selected as prime contractor for two United States ArmyFCSUAV systems. The FCS Class III UAV system contract was awarded to the company in late 2006 following a competitive downselect of four competing technologies. As part of that effort, the company flew the world's first autonomous autogyro. The company has been developing and flight-testing the X-49 experimental compound helicopter since the mid-2000s.