Bristol Centaurus
| Bristol Centaurus | |
|---|---|
.jpg) Bristol Centaurus on display in the Science Museum, London |
|
| Type: | Radial engine |
| Design country: | |
| Manufacturer: | |
| Production time: |
1942– |
| Number of pieces: |
approx. 2,500 |
The Centaurus was the culmination of the development of radial slide engines by the Bristol Aircraft Company . It was an 18-cylinder double radial engine that ultimately delivered over 3000 hp.
Like most Bristol developments, the design was based on previous designs. The cylinder bore was the same as that of Jupiter's 1918 at 5.75 in (146 mm). This measure was also used in the fourteen- cylinder Hercules . In the Centaurus , the stars were expanded by two cylinders each compared to the Hercules , resulting in a two-tier multiple radial engine with two nine-cylinder stars in a row and a displacement of 53.64 liters (3270 cui.) Instead of the 38.7 liters (2364 cui.) Hercules . This made it one of the largest British engines. To ensure sufficient air cooling , the two stars were arranged one behind the other, rotated by 20 degrees. The nine cylinders of the rear star - seen from the front - were located behind the free spaces of the front cylinders and thus received sufficient airflow for cooling. Thanks to the valveless Burt-McCollum slide control, the engine was also very speed-resistant.
Although the development was in principle already completed in 1938, production could not begin until 1942. The production of the Hercules used the capacities to the full and the war conditions did not allow any endangerment of the deliveries of the older engine. This extra time was spent improving the Centaurus' performance and reliability . In addition, there was no need for a 2000 hp engine in these early war times, as the aircraft types of that time were not yet designed for that much propulsion power.
In fact, the Centaurus was n't used until the end of the war. It was first installed in the Warwick developed from the Vickers Wellington . It was mainly used in later war and post-war developments such as the Bristol Brigand and Buckmaster , Blackburn Firebrand or the Hawker Tempest Mk 2 and Hawker Sea Fury . The engine was also used in civil aviation, for example in the failed Bristol Brabazon or in the Airspeed AS.57 Ambassador . The Bristol Britannia was originally designed for the use of the engine.
Comparable large double radial engines have been developed in the USA , for example the Pratt & Whitney R-4360 Wasp Major , Pratt & Whitney R-2800 Double Wasp and the Wright R-3350 Duplex Cyclone . However, the R-4360 Wasp Major could no longer be made operational during the war and the R-3350 Duplex Cyclone in the Boeing B-29 tended to overheat when taking off. The Centaurus actually had better starting conditions due to the early start of development, but the larger US aircraft engine industry was better able to assert itself on the world market after the war, especially since the era of large piston engines came to an end because of the superior jet engines .
Technical data (Centaurus VII, 1942)
- Type: air-cooled 18-cylinder four-stroke double radial engine
- Valve control: slide control, "Burt-McCollum" design
- Bore: 146 mm (5.75 in )
- Stroke: 178 mm (7 in)
- Displacement: 53,640 cm 3 (3270 cui. )
- Compression: 7.2: 1
- Power 2555 hp (1880 kw) at 2700 min -1
- specific power: 47.6 hp / liter (35.0 kW / liter)
- Dry weight: 1223 kg (2695 lb)
- Power-to-weight ratio : 0.479 kg / PS or 0.651 kg / kW (0.948 PS / lb)
literature
- Robert J. Raymond: Comparison of Sleeve and Poppet Valve Aircraft Piston Engines. (PDF; 2.0 MB), April 2005, technical article published on the website of the Aircraft Engine Historical Society
