The Curtiss OX-5 was an early V-8 American liquid-cooled aircraft engine built by Curtiss. It was the first American-designed aircraft engine to enter mass production, although it was considered obsolete when it did so in 1917. It nevertheless found widespread use on a number of aircraft, perhaps the most famous being the JN-4 "Jenny". Some 12,600 units were built through early 1919. The wide availability of the engine in the surplus market made it common until the 1930s, although it was considered unreliable for most of its service life.
The Hispano-Suiza 8 is a water-cooled V8 SOHC aero engine introduced by Hispano-Suiza in 1914 that went on to become the most commonly used liquid-cooled engine in the aircraft of the Entente Powers during the First World War. The original Hispano-Suiza 8A was rated at 140 hp (100 kW) and the later, larger displacement Hispano-Suiza 8F reached 330 hp (250 kW).
The Lycoming XR-7755 was the largest piston aircraft engine ever built in the United States, with 36 cylinders totaling about 7,750 in3 (127 L) of displacement and a power output of 5,000 horsepower (3,700 kilowatts). It was originally intended to be used in the "European bomber" that eventually emerged as the Convair B-36. Only two examples were built before the project was terminated in 1946.
The Klimov M-105 was a V12 liquid-cooled piston aircraft engine used by Soviet aircraft during World War II.
The Klimov VK-107 was a V-12 liquid-cooled piston aircraft engine used by Soviet aircraft during World War II.
The Mercedes D.IVa was a German six-cylinder, water-cooled, inline engine developed in 1917 for use in aircraft and built by Daimler Motoren Gesellschaft (DMG).
The Klimov M-103 is a V12 liquid-cooled piston aircraft engine used by Soviet aircraft during World War II.
The Hispano-Suiza 12X was an aircraft piston engine designed in France by Hispano-Suiza during the early 1930s. A 12-cylinder Vee, liquid-cooled design, the 12X was used on several aircraft types, some of them being used in limited numbers during World War II. Due to the 12X's limited power output, its derivative the more powerful Hispano-Suiza 12Y had a longer career.
The Hirth HM 512 was a 12-cylinder development of the earlier, 6-cylinder HM 506, produced in the late 1930s. Both were supercharged, inverted V, air-cooled engines.
The Green D.4 was a four-cylinder watercooled inline piston engine produced by the Green Engine Co in the UK in 1909. It produced about 60 hp (45 kW) and played an important role in the development of British aviation before World War I.
The Lorraine 12H Pétrel was a French V-12 supercharged, geared piston aeroengine initially rated at 370 kW (500 hp), but later developed to give 640 kW (860 hp). It powered a variety of mostly French aircraft in the mid-1930s, several on an experimental basis.
The Asso XI was a family of water-cooled, supercharged V12 piston aeroengines produced in the 1930s by Italian manufacturer Isotta Fraschini, and fitted on a number of aircraft types built by CANT, Caproni and others.
The Fiat A.25 was an Italian water-cooled aircraft engine from the 1920s. It produced 708 kW (950 hp) and was used by the Regia Aeronautica for fifteen years to power their Fiat BR.2 and BR.3 bombers.
The Hispano-Suiza 18R was an eighteen cylinder high performance water-cooled piston engine, in an 80° W or broad arrow layout, for use in racing aircraft, built in France during the latter half of the 1920s.
The SNECMA-Régnier 4L is a French four cylinder air-cooled inverted inline piston engine, introduced shortly after the end of World War II.
The Caffort 12Aa was a 12-cylinder, horizontally-opposed, piston aircraft engine designed and built in France during the latter half of the 1920s.
The Isotta Fraschini Asso Caccia, a.k.a. Isotta Fraschini Asso-450 Caccia, was an air-cooled, supercharged V12 piston aero engine produced in the late 1920s and early 1930s by Italian manufacturer Isotta Fraschini.
The De Dion-Bouton 130 hp aircraft engine, also referred to as De Dion-Bouton 12B, was a twelve-cylinder, air cooled vee aircraft engine that has been built by De Dion-Bouton.
The Renault 12Fe, or 300 CV, is a water-cooled V12 aero engine. The 12Fe was the most produced Renault aircraft engine and powered many French aircraft during WW1 and the 1920s.
The Galloway Atlantic is a 500 hp V12 aero engine that was ordered into production towards the end of WW1. The Atlantic saw postwar service in Handley Page V/1500 bombers built by Galloway’s parent company, William Beardmore & Co. In contemporary publications the type is often referred to as the Beardmore, or BHP, Atlantic or 500 hp.
