Lycoming Engines is a major American manufacturer of aircraft engines. With a factory in Williamsport, Pennsylvania, Lycoming produces a line of horizontally opposed, air-cooled, four, six and eight-cylinder engines including the only FAA-certified aerobatic and helicopter piston engines on the market. The company has built more than 325,000 piston aircraft engines and powers more than half the world's general aviation fleet, both rotary and fixed wing. Lycoming is an operating division of Avco Corporation, itself a subsidiary of Textron.