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Hub AI
BMW 801 AI simulator
(@BMW 801_simulator)
Hub AI
BMW 801 AI simulator
(@BMW 801_simulator)
BMW 801
The BMW 801 was a powerful German 41.8-litre (2,550 cu in) air-cooled 14-cylinder-radial aircraft engine built by BMW and used in a number of German Luftwaffe aircraft of World War II. Production versions of the twin-row engine generated between 1,560 and 2,000 PS (1,540–1,970 hp, or 1,150–1,470 kW). It was the most produced radial engine of Germany in World War II with more than 61,000 built.
The 801 was originally intended to replace existing radial types in German transport and utility aircraft. At the time, it was widely agreed among European designers[citation needed] that an inline engine was a requirement for high performance designs due to its smaller frontal area and resulting lower drag. Kurt Tank successfully fitted a BMW 801 to a new fighter design he was working on, and as a result the 801 became best known as the power plant for the famous Focke-Wulf Fw 190. The BMW 801 radial also pioneered the use of what would today be designated an engine control unit: its Kommandogerät engine management system took over the operation of several aviation engine management control parameters of the era, allowing proper operation of the engine with just one throttle lever.
In the 1930s, BMW took out a license to build the Pratt & Whitney Hornet engines. By the mid-30s they had introduced an improved version, the BMW 132. The BMW 132 was widely used, most notably on the Junkers Ju 52, which it powered for much of that design's lifetime.
In 1935 the RLM funded prototypes of two much larger radial designs, one from Bramo, the Bramo 329, and another from BMW, the BMW 139. BMW's design used many components from the BMW 132 to create a two-row engine with 14 cylinders,[citation needed] supplying 1,550 PS (1,529 hp, 1,140 kW). After BMW bought Bramo in 1939 both projects were merged into the BMW 801, learning from the problems encountered in both projects.
The BMW 139 was originally intended to be used in roles similar to those of the other German radials, namely bombers and transport aircraft, but midway through the program the Focke-Wulf firm's chief designer, Kurt Tank suggested it for use in the Focke-Wulf Fw 190 fighter project. Radial engines were rare in European designs as they were considered to have too large a frontal area for good streamlining and would not be suitable for high speed aircraft. They were most popular on naval aircraft, where their easier maintenance and improved reliability were highly valued. Efforts to improve these designs led to new cowling designs that reduced the concerns about drag. Tank felt that attention to detail could result in a streamlined radial that would not suffer undue drag, and would be competitive with inlines.
The main concern was providing cooling air over the cylinder heads, which generally required a very large opening at the front of the aircraft. Tank's solution for the BMW 139 was to use an engine-driven fan behind an oversized, flow-through hollow prop-spinner open at the extreme front, blowing air past the engine cylinders, with some of it being drawn through S-shaped ducts over a radiator for oil cooling. However this system proved almost impossible to operate properly with the BMW 139; early prototypes of the Fw 190 demonstrated terrible cooling problems. Although the problems appeared to be fixable, since the engine was already fairly dated in terms of design, in 1938 BMW proposed an entirely new engine designed specifically for fan-cooling that could be brought to production quickly.
The new design was given the name BMW 801 after BMW was given a new block of "109-800" engine numbers by the RLM to use after their merger with Bramo. The 801 retained the 139's older-style single-valve intake and exhaust, while most in-line engines of the era had moved to either three (as Junkers had done) or four valves per cylinder, or in British use for their own radials, sleeve valves. Several minor advances were worked into the design, including the use of sodium-cooled valves and a direct fuel injection system, manufactured by Friedrich Deckel AG of Munich.
The supercharger was rather basic in the early models, using a single-stage two-speed design directly geared to the engine (unlike the DB 601's hydraulically clutched version) which led to rather limited altitude performance, in keeping with its intended medium-altitude usage. One key advancement for the 801 was the Kommandogerät (command-device), a mechanical-hydraulic unit that automatically adjusted engine fuel flow, propeller pitch, supercharger setting, mixture and ignition timing in response to a single throttle lever, dramatically simplifying engine control. The Kommandogerät could be considered to be a precursor to the engine control units used for many vehicles' internal combustion engines of the late 20th and early 21st centuries.
BMW 801
The BMW 801 was a powerful German 41.8-litre (2,550 cu in) air-cooled 14-cylinder-radial aircraft engine built by BMW and used in a number of German Luftwaffe aircraft of World War II. Production versions of the twin-row engine generated between 1,560 and 2,000 PS (1,540–1,970 hp, or 1,150–1,470 kW). It was the most produced radial engine of Germany in World War II with more than 61,000 built.
The 801 was originally intended to replace existing radial types in German transport and utility aircraft. At the time, it was widely agreed among European designers[citation needed] that an inline engine was a requirement for high performance designs due to its smaller frontal area and resulting lower drag. Kurt Tank successfully fitted a BMW 801 to a new fighter design he was working on, and as a result the 801 became best known as the power plant for the famous Focke-Wulf Fw 190. The BMW 801 radial also pioneered the use of what would today be designated an engine control unit: its Kommandogerät engine management system took over the operation of several aviation engine management control parameters of the era, allowing proper operation of the engine with just one throttle lever.
In the 1930s, BMW took out a license to build the Pratt & Whitney Hornet engines. By the mid-30s they had introduced an improved version, the BMW 132. The BMW 132 was widely used, most notably on the Junkers Ju 52, which it powered for much of that design's lifetime.
In 1935 the RLM funded prototypes of two much larger radial designs, one from Bramo, the Bramo 329, and another from BMW, the BMW 139. BMW's design used many components from the BMW 132 to create a two-row engine with 14 cylinders,[citation needed] supplying 1,550 PS (1,529 hp, 1,140 kW). After BMW bought Bramo in 1939 both projects were merged into the BMW 801, learning from the problems encountered in both projects.
The BMW 139 was originally intended to be used in roles similar to those of the other German radials, namely bombers and transport aircraft, but midway through the program the Focke-Wulf firm's chief designer, Kurt Tank suggested it for use in the Focke-Wulf Fw 190 fighter project. Radial engines were rare in European designs as they were considered to have too large a frontal area for good streamlining and would not be suitable for high speed aircraft. They were most popular on naval aircraft, where their easier maintenance and improved reliability were highly valued. Efforts to improve these designs led to new cowling designs that reduced the concerns about drag. Tank felt that attention to detail could result in a streamlined radial that would not suffer undue drag, and would be competitive with inlines.
The main concern was providing cooling air over the cylinder heads, which generally required a very large opening at the front of the aircraft. Tank's solution for the BMW 139 was to use an engine-driven fan behind an oversized, flow-through hollow prop-spinner open at the extreme front, blowing air past the engine cylinders, with some of it being drawn through S-shaped ducts over a radiator for oil cooling. However this system proved almost impossible to operate properly with the BMW 139; early prototypes of the Fw 190 demonstrated terrible cooling problems. Although the problems appeared to be fixable, since the engine was already fairly dated in terms of design, in 1938 BMW proposed an entirely new engine designed specifically for fan-cooling that could be brought to production quickly.
The new design was given the name BMW 801 after BMW was given a new block of "109-800" engine numbers by the RLM to use after their merger with Bramo. The 801 retained the 139's older-style single-valve intake and exhaust, while most in-line engines of the era had moved to either three (as Junkers had done) or four valves per cylinder, or in British use for their own radials, sleeve valves. Several minor advances were worked into the design, including the use of sodium-cooled valves and a direct fuel injection system, manufactured by Friedrich Deckel AG of Munich.
The supercharger was rather basic in the early models, using a single-stage two-speed design directly geared to the engine (unlike the DB 601's hydraulically clutched version) which led to rather limited altitude performance, in keeping with its intended medium-altitude usage. One key advancement for the 801 was the Kommandogerät (command-device), a mechanical-hydraulic unit that automatically adjusted engine fuel flow, propeller pitch, supercharger setting, mixture and ignition timing in response to a single throttle lever, dramatically simplifying engine control. The Kommandogerät could be considered to be a precursor to the engine control units used for many vehicles' internal combustion engines of the late 20th and early 21st centuries.