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 horsepower (109 to 168 kW), with the basic O-360 producing 180.
The engine family has been installed in thousands of aircraft, including the Cessna 172, Piper Cherokee/Archer, Grumman Tiger, and many home-built craft. It has a factory rated time between overhaul (TBO) of 2000 hours or twelve years.
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 3⁄16 inch (4.76 mm), developing 210 hp (157 kW) .
The O-360 family of engines comprise 167 different models with 12 different prefixes. All have a 361-cubic-inch (5.92-liter) displacement and 5.125 and 4.375 in (130.2 and 111.1 mm) bore and stroke.
O-360 carbureted series
HO-360 horizontally mounted series for helicopter installation
LO-360 same as O-360, but with left-hand rotating crankshaft, for use in pairs on twin-engined aircraft
TO-360 turbocharged series
LTO-360 turbocharged left-hand rotation series
IO-360 fuel-injected series
LIO-360 same as IO-360, but with left-hand rotating crankshaft
AIO-360 inverted mount (dry sump aerobatic) fuel-injected series
AEIO-360 aerobatic fuel-injected series
HIO-360 horizontally mounted fuel-injected series for helicopters
LHIO-360 left-hand rotation, fuel-injected, horizontally mounted for helicopters
TIO-360 turbocharged and fuel-injected series
O-360
LO-360
Beechcraft Duchess
Piper PA-44-180 Seminole
IO-360
LIO-360
Piper PA-34 Seneca I
Diamond DA42
AIO-360
Stephens Akro
AEIO-360
Aero-Cam Slick 360
Aviat Eagle II
American Champion Super Decathlon
Extra EA-200
FFA AS-202 Bravo
Grob G 115E
Mudry CAP 10
Peña Capeña
Pitts Special
Tech Aero TR 200
Valmet L-70 Vinka
HIO-360
Enstrom F-28
OH-23 Raven
Schweizer 300
LHIO-360
Silvercraft SH-3
Silvercraft SH-4
Data from Type Certificate Data Sheet E-286
Type: Four-cylinder, dual magneto, horizontally opposed, four-stroke aircraft engine
Bore: 5.125 in (130 mm)
Stroke: 4.375 in (111 mm)
Displacement: 361 cu in (5,916 cc)
Dry weight: 258 lb (117 kg)
Fuel type: 91/96 avgas minimum grade
Oil system: 8 US qt (8 l) dry sump
Cooling system: air-cooled
Power output: 180 hp (134 kW) at 2700 rpm
Compression ratio: 8.5:1
