The Bristol Jupiter is a British nine-cylinder single-row piston radial engine that was built by the Bristol Aeroplane Company. Originally designed late in World War I and known as the Cosmos Jupiter, a lengthy series of upgrades and developments turned it into one of the finest engines of its era.
The Bristol Pegasus is a British nine-cylinder, single-row, air-cooled radial aero engine. Designed by Roy Fedden of the Bristol Aeroplane Company, it was used to power both civil and military aircraft of the 1930s and 1940s. Developed from the earlier Mercury and Jupiter engines, later variants could produce 1,000 horsepower from its capacity of 1,750 cubic inches by use of a geared supercharger.
The Phoenix was an experimental version of the Bristol Aeroplane Company's Pegasus engine, adapted to run on the Diesel cycle. Only a few were built between 1928 and 1932, although samples fitted to a Westland Wapiti held the altitude record for diesel-powered aircraft at 27,453 ft from 11 May 1934 until World War II. The primary advantage of the Phoenix was better fuel efficiency at cruise, by up to 35%.
The Bristol Perseus was a British nine-cylinder, single-row, air-cooled radial aircraft engine produced by the Bristol Engine Company starting in 1932. It was the first production sleeve valve aero engine.
The Aquila was a nine-cylinder single-row radial aircraft engine designed by the Bristol Engine Company starting in 1934. A sleeve valve engine, its basic design was developed from the Bristol Perseus. The Aquila was never used in production, but further developments led to the Bristol Hercules, Bristol Taurus, and Bristol Centaurus.
The Bristol Hercules is a 14-cylinder two-row radial aircraft engine designed by Sir Roy Fedden and produced by the Bristol Engine Company starting in 1939. It was the most numerous of their single sleeve valve designs, powering many aircraft in the mid-World War II timeframe.
The Centaurus was the final development of the Bristol Engine Company's series of sleeve valve radial aircraft engines. The Centaurus is an 18-cylinder, two-row design that eventually delivered over 3,000 hp (2,200 kW). The engine was introduced into service late in the Second World War and was one of the most powerful aircraft piston engines to see service.
The de Havilland Gipsy Major or Gipsy IIIA is a four-cylinder, air-cooled, inverted inline engine used in a variety of light aircraft produced in the 1930s, including the famous Tiger Moth biplane. Many Gipsy Major engines still power vintage aircraft types.
The Pratt & Whitney R-1830 Twin Wasp is an American air-cooled radial aircraft engine. It displaces 1,830 cu in (30.0 L) and its bore and stroke are both 5.5 in (140 mm). The design traces its history to 1929 experiments at Pratt & Whitney on twin-row designs. Production began in 1932 and it was widely used during the 1930s.
The Pratt & Whitney R-1535 Twin Wasp Junior was an engine used in American aircraft in the 1930s. The engine was introduced in 1932 as a 14-cylinder version of the 9-cylinder R-985. It was a two-row, air-cooled radial design. Displacement was 1,535 cu in (25.2 L); bore and stroke were both 5+3⁄16 in (132 mm).
The Rolls-Royce Kestrel is a 21.25 litre V-12 aircraft engine from Rolls-Royce. It was their first cast-block engine, and used as the pattern for most of their future piston-engine designs. Used during the interwar period, it was fitted to a number of British fighters and bombers of the era, including the Hawker Fury and Hawker Hart family, and the Handley Page Heyford. The Kestrel engine was also sold to international air force customers; in this role it was used to power prototypes of the German Messerschmitt Bf 109 and the Junkers Ju 87 "Stuka" dive-bomber, as the Junkers Jumo 210 engines were not ready to be fitted. Several examples of the Kestrel engine remain airworthy today.
The Rolls-Royce Falcon is an aero engine developed in 1915. It was a smaller version of the Rolls-Royce Eagle, a liquid-cooled V-12 of 867 cu in capacity. Fitted to many British World War I-era aircraft, production ceased in 1927. The Falcon was designed by R.W. Harvey-Bailey.
The Armstrong Siddeley Leopard was a British 14-cylinder twin-row air-cooled radial aero engine developed in 1927 by Armstrong Siddeley. It was the most powerful radial engine in the world when introduced.
The Armstrong Siddeley Jaguar is an aircraft engine developed by Armstrong Siddeley. The Jaguar was a petrol-fuelled air-cooled 14-cylinder two-row radial engine design. The Jaguar III was first used in 1923, followed in 1925 by the Jaguar IV and in 1927 by the Jaguar VI. In 1925 the Jaguar became the first production aero engine incorporating a geared supercharger.
The Armstrong Siddeley Panther was a 27-litre 14-cylinder twin-row air-cooled radial aero engine developed by Armstrong Siddeley. It was originally named the Jaguar Major.
The Alvis Leonides Major is a British air-cooled 14-cylinder radial aero engine developed by Alvis from the earlier nine-cylinder Leonides.
The Bristol Hydra was an experimental 16-cylinder, twin-row radial aircraft engine built by the Bristol Engine Company. It is a relatively rare example of a radial with an even number of cylinders per row – it is often claimed that radial engines require an odd number of cylinders, but this is simply easier, not physically required. Only two Hydras were built, the type never entered production.
The Rolls-Royce Exe, or Boreas, was a 24-cylinder air-cooled X block sleeve valve aircraft engine intended primarily for the new Fairey Fleet Air Arm aircraft, particularly the Fairey Barracuda. The Exe was relatively powerful for its era, producing about 1,100 hp (820 kW). This is notable given the relatively small 1,300 cubic inches (22 L) displacement, the Merlin requiring 1,600 cubic inches (27 L) for approximately the same power level. The X-24 layout made this quite a compact engine.
The Armstrong Siddeley Tiger was a British 14-cylinder air-cooled aircraft radial engine developed by Armstrong Siddeley in the 1930s from their Jaguar engine. The engine was built in a number of different versions but performance and dimensions stayed relatively unchanged. The Tiger VIII was the first British aircraft engine to use a two-speed supercharger.
The Napier Rapier was a British 16-cylinder H pattern air-cooled aero engine designed by Frank Halford and built by Napier & Son shortly before World War II.
