Pratt & Whitney is a U.S. -based aerospace manufacturer with global service operations. It is a subsidiary of United Technologies Corporation (UTC). Pratt & Whitney's aircraft engines are widely used in both civil aviation and military aviation. Its headquarters are in East Hartford, Connecticut, USA. As one of the "big three" aero-engine manufacturers, it competes with General Electric and Rolls-Royce, although it has also formed joint ventures with both of these companies.