The Jumo 205 aircraft engine was the most famous of a series of aircraft diesel engines produced by Junkers. The Jumo 204 first entered service in 1932. Later engines of this type comprised the experimental Jumo 206 and Jumo 208, with the Jumo 207 produced in some quantity for the Junkers Ju 86P and -R high-altitude reconnaissance aircraft, and the 46-meter wingspan, six-engined Blohm & Voss BV 222 Wiking flying boat. All three of these variants differed in stroke and bore and supercharging arrangements. In all, more than 900 of these engines were produced, in the 1930s and through most of World War II.
The Monosoupape, was a rotary engine design first introduced in 1913 by Gnome Engine Company. It used a clever arrangement of internal transfer ports and a single pushrod-operated exhaust valve to replace the many moving parts found on more conventional rotary engines, and made the Monosoupape engines some of the most reliable of the era. British aircraft designer Thomas Sopwith described the Monosoupape as "one of the greatest single advances in aviation".
The Jumo 210 was Junkers Motoren's first production inverted V12 gasoline aircraft engine, first produced in the early 1930s. Depending on the version it produced between 610 and 730 PS and can be considered a counterpart of the Rolls-Royce Kestrel in many ways. Although originally intended to be used in almost all pre-war designs, rapid progress in aircraft design quickly relegated it to the small end of the power scale by the late 1930s. Almost all aircraft designs switched to the much larger Daimler-Benz DB 600, so the 210 was produced only for a short time before Junkers responded with a larger engine of their own, the Junkers Jumo 211.
The Junkers L 5 was a six-cylinder, water-cooled, inline engine for aircraft built in Germany during the 1920s. First run in 1925, it was a much enlarged development of the Junkers L2.
The Alfa Romeo 115 was an Italian six-cylinder air-cooled inverted inline engine for aircraft use, mainly for training and light planes, based on the de Havilland Gipsy Six engine. Production totalled approximately 1,600 units. Derivatives of the 115 include the -1, bis, ter and Alfa Romeo 116.
The Alfa Romeo 110 was an Italian four cylinder air-cooled inverted inline engine for aircraft use, mainly for trainers and light aircraft. The Alfa Romeo 110 was based on the de Havilland Gipsy Major, with approximately 500 units produced. Derivatives of the 110 include the -1, ter and Alfa Romeo 111.
The Walter Venus was a seven-cylinder, air-cooled, radial engine for aircraft use, built in Czechoslovakia in the late 1920s.
In 1914 Otto Hieronimus manufactured the six-cylinder Hiero E, also known as the Hiero 6 engine which was derived from earlier 4-cylinder engines. The Hiero engine like the Austro-Daimler powered many of Austria's World War I aircraft. Hiero aircraft engines were designed by Otto Hieronimus, a famous Austrian auto racer of the early 1900s. His initial designs were liquid-cooled inline engines built by the Laurin & Klement Automobile Works of Austria.
The Anzani 10 was a 1913 10-cylinder air-cooled radial aircraft engine. It powered several experimental aircraft and also the later production versions of the Caudron G.3 reconnaissance aircraft, the Caudron G.4 bomber/trainer and the first production Cessna, the Model AA.
The ADC Cirrus is a series of British aero engines manufactured using surplus Renault parts by the Aircraft Disposal Company (ADC) in the 1920s.
The Sunbeam Matabele was a British 12-cylinder aero engine that was first flown in 1918. The Matabele was the last iteration of one of Sunbeam's most successful aero engines, the Cossack.
The Armstrong Siddeley Hyena was a British aero engine developed by Armstrong Siddeley. Designed in the 1930s, it was an unusual experimental radial engine with inline cylinder banks. It was flown using an Armstrong Whitworth A.W.16 fighter aircraft as a test bed. Unresolved problems with cooling of the rear cylinders prevented the engine from going into production. Few details of this engine survive as company records were lost.
The de Havilland Ghost was a British V-8 aero engine that first ran in 1928.
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 Junkers L2 was Junkers' first water-cooled four-stroke engine and the first to be built on a production line, though only 58 were made. It was a six-cylinder inline engine and powered many Junkers aircraft until replaced by the more powerful L5.
The Junkers L55 was Junkers' first V-12 engine, appearing in 1927 and based on a pair of six-cylinder L5s. In 1928 a supercharger was added. It was used in one or two Junkers aircraft in their early development but was replaced by the geared L88 geared V-12 of 1929.
The Junkers L88 was Junkers' first geared V-12 engine, appearing c.1930 and based on a pair of 6-cylinder L8s. In 1932 a supercharger was added. It was used in the world's second working pressurised aircraft, the Junkers Ju 49 and, for a while, in the large G 38 airliner and its Japanese built military version.
One of Avia's own designs, the 1930s Avia Rk.12 was a seven-cylinder radial engine with a rated output of 150 kW (200 hp), built in Czechoslovakia.
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 Fiat AN.1 was an experimental Italian water-cooled diesel straight six cylinder aircraft engine from the late 1920s.
