| Aquila | |
|---|---|
 | |
| Type | Piston aircraft engine |
| Manufacturer | Bristol Aeroplane Company |
| First run | 1934 |
| Major applications | Bristol Bulldog Bristol Bullpup |
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 Aquila was developed two years after the somewhat larger Perseus, both being sleeve valve designs. The primary difference was in size, the Perseus being based on the 5.75 by 6.5 in (146 by 165 mm) cylinder used in the Mercury engine, while the Aquila used a new and smaller 5 by 5.375 in (127.0 by 136.5 mm) sized cylinder. The result was a reduction in displacement from 1520 to 950 cubic inches (24.9 to 15.6 L).
The first Aquila engine delivered a modest 365 horsepower (272 kW ), which was unspectacular for an engine of this size. It soon developed into more powerful versions as improvements were worked into the line (as well as similar changes to the Perseus), and by 1936 it had improved to 500 hp (370 kW). This would have made it an excellent replacement for the Bristol Jupiter, which ended production at 590 hp (440 kW) three years earlier, but by this time almost all interest was on ever-larger engines.
Note: [1]
Data fromLumsden. [2]
Related development
Related lists
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 radial engine is a reciprocating type internal combustion engine configuration in which the cylinders "radiate" outward from a central crankcase like the spokes of a wheel. It resembles a stylized star when viewed from the front, and is called a "star engine" in some other languages.
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 Bristol Mercury is a British nine-cylinder, air-cooled, single-row, piston radial 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 Jupiter engine, later variants could produce 800 horsepower (600 kW) from its capacity of 1,500 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 Napier Sabre is a British H-24-cylinder, liquid-cooled, sleeve valve, piston aero engine, designed by Major Frank Halford and built by D. Napier & Son during World War II. The engine evolved to become one of the most powerful inline piston aircraft engines in the world, developing from 2,200 hp (1,600 kW) in its earlier versions to 3,500 hp (2,600 kW) in late-model prototypes.
The Taurus is a British 14-cylinder two-row radial aircraft engine, produced by the Bristol Engine Company starting in 1936. The Taurus was developed by adding cylinders to the existing single-row Aquila design and transforming it into a twin-row radial engine, creating a powerplant that produced just over 1,000 horsepower with very low weight.
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 Armstrong Siddeley Cheetah is a seven-cylinder British air-cooled aircraft radial engine of 834 cu in capacity introduced in 1935 and produced until 1948. Early variants of the Cheetah were initially known as the Lynx Major.
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 Bristol Draco was an air-cooled nine-cylinder radial engine from the British manufacturer Bristol Aeroplane Company. It was essentially a version of their famous Pegasus converted to use a fuel injection system.
The Bristol Lucifer was a British three-cylinder, air-cooled, radial engine for aircraft. Built in the UK in the 1920s by the Bristol Aeroplane Company, it produced 100 horsepower (75 kW).
The Bristol Titan was a British five-cylinder air-cooled radial engine, designed and built by the Bristol Aeroplane Company in the late 1920s. It had the same size cylinders as the earlier Bristol Mercury engine, 5.75 in × 6.5 in, and produced between 200–240 hp (150–180 kW). Later versions of the Bristol Titan also used a Farman-style reduction gear produced by Gnome-Rhône.
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 Armstrong Siddeley Ounce was a small two-cylinder aero engine developed by Armstrong Siddeley in 1920. The engine was originally conceived as a test piece but ran very well and was put into production for early ultralight aircraft and use in target drones. The Ounce used two cylinders from the preceding Jaguar I radial engine.
The Bristol Neptune was a seven-cylinder air-cooled radial engine developed in 1930. It had the same size cylinders as the earlier Mercury and Titan engines, 5.75 in (146 mm) x 6.5 in (165 mm) which gave a displacement of 1,182 cu in and produced a maximum of 320 horsepower (239 kW). The Neptune was effectively a seven-cylinder version of the Titan.
The Cosmos Mercury was a fourteen-cylinder twin-row air-cooled radial aeroengine. Designed by Roy Fedden of Cosmos Engineering, it was built in the United Kingdom in 1917. It produced 347 horsepower (259 kW). It did not enter production; a large order was cancelled due to the Armistice.
The Wolseley Aquarius I or A.R.7 was a British seven-cylinder, air-cooled radial aero engine that first ran in 1933, it was designed and built by Wolseley Motors. Intended for the military trainer aircraft market few were produced, as Wolseley withdrew from the aero engine market in 1936.