The Lycoming O-320 is a large family of naturally aspirated, air-cooled, four-cylinder, direct-drive engines produced by Lycoming Engines. They are commonly used on light aircraft such as the Cessna 172 and Piper Cherokee. Different variants are rated for 150 or 160 horsepower. As implied by the engine's name, its cylinders are arranged in horizontally opposed configuration and a displacement of 320 cubic inches (5.24 L).
The Warner Scarab is an American seven-cylinder radial aircraft engine, that was manufactured by the Warner Aircraft Corporation of Detroit, Michigan in 1928 through to the early 1940s. In military service the engine was designated R-420.
The Continental R-670 was a seven-cylinder four-cycle radial aircraft engine produced by Continental displacing 668 cubic inches and a dry weight of 465 lb (211 kg). Horsepower varied from 210 to 240 at 2,200 rpm. The engine was the successor to Continental's first radial engine, the 170 hp Continental A-70. This engine was used on many aircraft in the 1930s and 1940s. The R-670 was widely used in the PT-17 Stearman primary training aircraft of the U.S. military.
The Franklin O-335 was an American air-cooled aircraft engine of the 1940s. The engine was of six-cylinder, horizontally-opposed layout and displaced 335 cu in (5.5 L). The power output of later variants was 225 hp (168 kW).
The Franklin O-175 was an American air-cooled aircraft engine of the 1940s. The engine was of horizontally-opposed four-cylinder and displaced 175 cu in (2.9 L). The power output was nominally 80 hp (60 kW). A later variant was designated O-180, despite sharing the same displacement.
The Agusta GA.140/V is a 4-cylinder, air-cooled, horizontally opposed engine mounted vertically, developed in Italy for helicopter use and produced from 1962 to 1969.
The Lycoming O-290 is a dual ignition, four-cylinder, air-cooled, horizontally opposed aircraft engine. It was first run in 1939, and entered production three years later.
The Gnome-Rhône 14M was a small 14-cylinder two-row air-cooled radial engine that was used on several French and German aircraft of World War II. While having the same appearance, number of pistons (14) and two-row layout typical of Gnome-Rhône radial engines, the 14M was built to a smaller frame intended to power a lighter class of aircraft. It was designed with lower displacement and power, smaller in size and with less weight compared to the larger, heavier Gnome-Rhône 14N and its well-known predecessor.
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 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 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 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 HKS 700E is a twin-cylinder, horizontally opposed, four stroke, carburetted aircraft engine, designed for use on ultralight aircraft, powered parachutes and ultralight trikes. The engine is manufactured by HKS, a Japanese company noted for its automotive racing engines.
The KFM 112M is a four-cylinder, four-stroke, dual ignition, horizontally opposed aircraft engine designed for ultralight aircraft and motor gliders.
The Nelson H-63, known in the US military designation system as the YO-65, is an American dual ignition, four-cylinder, horizontally opposed, two-stroke aircraft engine that was developed by the Nelson Engine Company for use in helicopters and light aircraft. The engine designation means horizontally opposed 63 cubic inch displacement.
The Franklin O-500 was an American air-cooled aircraft engine that first ran in the mid-1940s. The engine was of six-cylinder, horizontally-opposed layout and displaced 500 cu in (8 L). The power output was 215 hp (160 kW).
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 Hirth HM 501 was a 6-cylinder air-cooled inverted in-line engine that was developed by Hirth Motoren GmbH in the late 1930s, from the 4-cylinder HM 500 and used principally on the submarine-born Arado Ar 231.
