Lycoming O-360

O-360
Lycoming IO-360-A1B6
Type Piston aircraft engine
National origin United States
Manufacturer Lycoming Engines
First run 1952
1963 (injected version)
Major applications Cessna 172 R & S
Cessna 177 Cardinal
Mooney M20
Produced 1955–present
Developed into Lycoming IO-390
Lycoming O-540
Lycoming IO-720

The Lycoming O-360 is a family of four-cylinder, direct-drive, horizontally opposed, air-cooled, piston aircraft engines. Engines in the O-360 series produce between 145 and 225 hp (110 and 170 kW), with the basic O-360 producing 180 hp (130 kW).

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 or twelve years. 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.

The first O-360 certified was the A1A model, certified on 20 July 1955 to United States CAR 13 effective March 5, 1952 as amended by 13-1 and 13-2. The Lycoming IO-390 is an O-360 which has had its cylinder bore increased by 316 inch (4.8 mm), developing 210 hp (160 kW).