The Lycoming O-360 is a family of four-cylinder, direct-drive, horizontally opposed, air-cooled, piston aircraft engines.

[1] The engine family has been installed in thousands of aircraft, including the Cessna 172, Piper Cherokee/Archer, Grumman Tiger, and many home-built types.

It has a factory rated time between overhaul (TBO) of 2000 hours[1] or twelve years.

[2] O-360 family engines are also widely used in airboats, most notably in the Hurricane Aircats used by the US Army during the Vietnam War.

[4] The Lycoming IO-390 is an O-360 which has had its cylinder bore increased by 3⁄16 inch (4.8 mm), developing 210 hp (160 kW).