The Lycoming O-235 is a family of four-cylinder, air-cooled, horizontally opposed, piston aircraft engines that produce 100 to 135 hp, derived from the earlier O-233 engine.
The Lycoming O-320 is a large family of naturally aspirated, 320 cu in (5.2 L) air-cooled, horizontally-opposed four-cylinder, direct-drive engines produced by Lycoming Engines. Introduced in 1953, it is commonly used on light aircraft such as the Cessna 172 and Piper Cherokee, and remains in production as of 2024. Different variants are rated for 150 or 160 horsepower.
The Lycoming O-540 is a family of air-cooled six-cylinder, horizontally opposed fixed-wing aircraft and helicopter engines of 541.5 cubic inches (8,874 cc) displacement, manufactured by Lycoming Engines. The engine is a six-cylinder version of the four-cylinder Lycoming O-360.
The Lycoming IO-720 engine is a large displacement, horizontally opposed, eight-cylinder aircraft engine featuring four cylinders per side, manufactured by Lycoming Engines.
The Continental O-240 engine is a four-cylinder, horizontally opposed, air-cooled aircraft engine that was developed in the late 1960s for use in light aircraft by Continental Motors, Inc. The first O-240 was certified on 7 July 1971.
The Lycoming O-145 is a family of small, low-horsepower, four-cylinder, air-cooled engines. It was Lycoming Engines' first horizontally opposed aircraft engine and was produced from 1938 until the late 1940s. The family includes the reduction-geared GO-145. The O-145 received its Approved Type Certificate on 13 Jun 1938.
The Continental IO-360 is a family of fuel-injected air-cooled, horizontally opposed six-cylinder aircraft engines manufactured by Continental Motors in the United States of America, now part of AVIC International since 2010.
The Continental O-470 engine is a family of carbureted and fuel-injected six-cylinder, horizontally opposed, air-cooled aircraft engines that was developed especially for use in light aircraft by Continental Motors. Engines designated "IO" are fuel-injected.
The Continental IO-550 engine is a large family of 9 liter fuel injected six-cylinder, horizontally opposed, air-cooled aircraft engines that were developed for use in light aircraft by Teledyne Continental Motors. The first IO-550 was delivered in 1983 and the type remains in production.
The Lycoming IO-580 engine is a horizontally opposed, six-cylinder aircraft engine featuring three cylinders per side, manufactured by Lycoming Engines.
The Lycoming GSO-580 is a family of eight-cylinder horizontally opposed, supercharged, carburetor-equipped aircraft engines for both airplanes and helicopters, manufactured by Lycoming Engines in the late 1950s and early 1960s.
The Lycoming TIO-541 engine is a turbocharged, fuel-injected, horizontally opposed, six-cylinder aircraft engine featuring three cylinders per side, manufactured by Lycoming Engines.
The Lycoming O-435 is an American six-cylinder, horizontally opposed fixed-wing aircraft and helicopter engine made by Lycoming Engines. The engine is a six-cylinder version of the four-cylinder Lycoming O-290.
The Lycoming IO-233 is a non-certified four-cylinder, air-cooled, horizontally opposed piston aircraft engine that produces between 100 hp (75 kW) and 116 hp (87 kW).
The Lycoming O-340 is a family of four-cylinder horizontally opposed, carburetor-equipped aircraft engines, that was manufactured by Lycoming Engines in the mid-1950s.
The Packard X-2775 was an American experimental liquid-cooled aircraft engine. The engine was constructed as a single crankcase with four banks of six cylinders in what is close to an X-configuration. The engine consisted of two 60° V12 engines, one upright and one inverted, sharing a common crankcase. Although technically incorrect, the engine has been characterized as two Packard 1A-1500 V-12 engines coupled with a mutual crankcase.
The D-Motor LF26 is a lightweight liquid cooled side-valve four-stroke flat four, 2.7 litre petrol aircraft engine, produced by D-Motor in Deerlijk, Belgium.
The Superior Air Parts Vantage is a type certified piston aircraft engine developed by Superior Air Parts of Coppell, Texas, United States and based upon the non-certified Superior Air Parts XP-360. The design is officially designated the Superior Air Parts O-360 and IO-360. Vantage is a marketing name.
The Lycoming DEL-120 is an aircraft diesel engine produced by Lycoming Engines using automotive technology and initially powering unmanned aircraft. Because the DEL-120 is a non-certified engine and is meant for military use only, there is no civil application of this engine.
The Continental IO-370 engine is a family of fuel injected four-cylinder, horizontally opposed, air-cooled aircraft engines that were developed for use in light aircraft by Continental Aerospace Technologies. There is no carbureted version of this engine, which would have been designation O-370, therefore the base model is the IO-370.
