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BMW VI
BMW VI
BMW VI
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BMW VI
BMW VI at the Technik-Museum Berlin
Type V engine
Manufacturer BMW
First run 1926
Major applications Heinkel He 51
Kawasaki Ki-10
Developed from BMW IV
Developed into BMW VII
Mikulin M-17

The BMW VI was a water-cooled V-12 aircraft engine built in Germany in the 1920s. It was one of the most important German aero engines in the years leading up to World War II, with thousands built. It was further developed as the BMW VII and BMW IX, although these saw considerably less use. It was also produced in the Soviet Union as the M-17 and Japan as the Kawasaki Ha-9.

Design and development

[edit]
Front view of the BMW VI

The BMW VI was the first twelve-cylinder engine built by the BMW. It essentially consisted of two cylinder banks from the six-cylinder BMW IV bolted to a common cast aluminium crankcase at a 60-degree included angle between the cylinder banks. Series production commenced in 1926 after type approval had been granted. From 1930 on, after 1000 engines of the BMW VI type had already been delivered, Germany was again permitted to construct military aircraft. The sudden additional demand resulted in the production figures increasing rapidly. In 1933 the BMW VI was used for BMW's first experiments with direct fuel injection.

The BMW VI was the chosen source of power for numerous record-breaking and long-distance flights, including an east-to-west crossing of the Atlantic in 1930 and a round-the world flight in 1932, both by Wolfgang von Gronau in an open Dornier Wal flying boat powered by two BMW VI engines.

The BMW VI was put to unusual use as a power unit for the "Rail Zeppelin" high-speed railcar. Many versions of the BMW VI engine were developed, and it was built under license in Japan and the Soviet Union. This was further evidence of the reliability of an engine with which BMW made a fundamental contribution to the build-up of German air transport. At least 9,200 were built between 1926 and 1938. The engine was license-built in the Soviet Union under the supervision of Mikulin, who then further developed it as the M-17. More license built engines were produced by Kawasaki Heavy Industries in Japan as the Kawasaki Ha9 (long designation:- Army Type 98 850hp Liquid Cooled In-line).

Variants

[edit]

5.5, 6 or 7.3 denotes compression ratio. No additional letter denotes BMW carburetor and direct-drive propeller (7.3), u denotes a propeller reduction gear (7.3u), z denotes Zenith carburetor (7.3z), zu denotes Zenith carburetor and propeller reduction gear (7.3zu).

BMW VI at the Technik-Museum Berlin
BMW VI 5.5
Compression ratio 5.5:1, 600–650 PS (592–641 hp) at up to 1600 rpm at sea level
BMW VI 6.0
Compression ratio 6:1, 630–660 PS (621–651 hp) at up to 1650 rpm at sea level, 80 Octane fuel
BMW VI 7.3
Compression ratio 7.3:1 680–750 PS (671–740 hp) at up to 1700 rpm at sea level, 87 Octane fuel
Mikulin M-17
Main article: Mikulin M-17
Licence production in the USSR
Kawasaki Ha9
(long designation:- Army Type 98 850hp Liquid Cooled In-line) licence production in Japan by Kawasaki

Applications

[edit]
BMW VI head detail

Specifications (BMW VI 7.3z)

[edit]
Side view of the BMW VI

Data from Flugzeug-Typenbuch. Handbuch der deutschen Luftfahrt- und Zubehör-Industrie 1944 [1]

General characteristics

  • Type: V-12, 60° water-cooled piston engine
  • Bore: 160 mm (6.30 in)
  • Stroke: 190 mm (7.48 in) / 199 mm (7.83 in) (different between right and left cylinder bank due to articulated connecting rods).
  • Displacement: 46.9 L (2,862.01 cu in)
  • Length: 1,810 mm (71.26 in)
  • Width: 859 mm (33.82 in)
  • Height: 1,103 mm (43.43 in)
  • Dry weight: 510 kg (1,124 lb)

Components

Performance

  • Power output:
  • 750 PS (740 hp; 552 kW) for takeoff at 1,700 rpm (1 minute) at sea level
  • 690 PS (681 hp; 507 kW) at 1,650 rpm (5 minutes) at sea level
  • 620 PS (612 hp; 456 kW) at 1,590 rpm (30 minutes) at sea level
  • 550 PS (542 hp; 405 kW) at 1,530 rpm (max. duration) at sea level
  • 0.23 kg/PSh (0.514 lb/(hp⋅h); 0.313 kg/kWh) at 1,590 rpm
  • 0.225 kg/PSh (0.503 lb/(hp⋅h); 0.306 kg/kWh) at 1,530 rpm
  • Oil consumption: 0.003–0.01 kg/PSh (0.007–0.022 lb/(hp⋅h); 0.004–0.014 kg/kWh) at 1,530 rpm
  • Power-to-weight ratio: 1.47 PS/kg (0.66 hp/lb; 1.08 kW/kg)
  • B.M.E.P.: 6.9 atm (7.0 bar; 101 psi)

See also

[edit]

Related development

Comparable engines

Related lists

References

[edit]

Further reading

[edit]
Revisions and contributorsEdit on WikipediaRead on Wikipedia

BMW VI

View on Grokipedia
from Grokipedia
The BMW VI was a water-cooled, 60-degree V-12 engine developed and produced by in , entering the market in 1926 as the company's first twelve-cylinder aero engine. Featuring a bore of 160 mm and stroke of 190 mm (right bank) / 199 mm (left bank) for a total displacement of 46.9 liters, it was available in direct-drive and 1.6:1 reduction-geared variants, with typical outputs ranging from 600 to 750 horsepower at 1,600 rpm depending on the model and configuration. The engine's robust design, including aluminum crankcase construction in geared versions and a dry weight of approximately 544 kg, made it a benchmark for reliability and performance in interwar . Derived from BMW's earlier inline-six IV series with shared cylinder technology, the VI was designed starting in 1925 to meet growing demands for higher power in commercial and military aircraft, passing type approval tests in 1926 and entering serial production shortly thereafter. Production continued until 1937 at BMW facilities, with licensed manufacturing extending into the early 1940s; its success led to extensive licensed production abroad, with tens of thousands of units built worldwide in total, including foreign copies such as the Soviet Mikulin M-17 and Japanese Kawasaki Ha-9 (Army Type 98). The engine powered a wide array of notable aircraft, including the Dornier Do J Wal flying boat, Junkers W.33 mail plane, early prototypes of the Junkers Ju 52 airliner, and the Heinkel He 111 bomber, contributing to numerous speed records, long-distance flights, and the Rail Zeppelin experimental high-speed train that achieved 230 km/h in 1931. Beyond , the BMW VI's versatility influenced experimental land vehicles like the Brutus project, where a 750 hp variant was mounted on a 1908 for demonstration purposes. Its liquid-cooled configuration and master-slave system (six main and six auxiliary rods) provided smooth operation and adaptability, cementing BMW's reputation in aero-engine manufacturing during the and before the shift to radial and inverted inline designs.

Design and development

Origins from BMW IV

The BMW VI engine originated from the BMW IV, a water-cooled inline-six developed during the post-World War I era, by adapting its cylinder design into a more powerful V-12 configuration. In , BMW engineers began work on this evolution, essentially combining two modified cylinder banks from the BMW IV into a 60° V-12 layout to meet the growing demand for higher-output powerplants suitable for larger, multi-engine . The primary design goals centered on achieving substantially greater power—targeting outputs in the 600-750 PS range—while preserving the reliability and liquid-cooling efficiency of the IV, which had proven effective in earlier applications. This shift addressed the limitations of inline engines for emerging heavy , emphasizing scalability without compromising operational dependability. Early prototypes retained key IV features, such as the water-cooled cylinders, but incorporated a new 60° V arrangement with a bore of 160 mm and strokes of 190 mm (one bank) and 199 mm (other bank) due to the articulated system, resulting in a displacement of 46.9 liters. The first bench tests occurred in 1925, validating the core design under various compression ratios to optimize performance. Key engineering challenges included transitioning from the inline to V configuration, which required a robust new crankshaft supported by seven plain bearings to handle increased loads and vibrations. Cooling system adaptations were also critical, involving an aluminum or Elektron alloy crankcase to enhance heat dissipation in the larger V-12 setup while maintaining the liquid-cooling principles of the BMW IV.

Key milestones and testing

The BMW VI's refinement phase spanned 1925 to 1926, culminating in type approval in June 1926 after comprehensive ground and flight testing to validate its performance and reliability. These evaluations addressed key engineering hurdles, such as ensuring consistent power output under varying conditions, before advancing to series production. The core V-12 layout, derived from the BMW IV, underwent iterative enhancements during this period to meet aviation demands. Testing encompassed endurance runs surpassing 100 hours to confirm durability, altitude simulations that tested the engine's efficacy at reduced air pressures, and integration trials with prototype aircraft including the to verify seamless installation and operational harmony. These trials highlighted initial limitations in sustained operation and high-altitude efficiency, prompting targeted refinements. Notable improvements included bolstering the supercharging system for sustained power at elevation, elevating the progressively from 5.5:1 to 7.3:1 across iterations to boost efficiency, and refining the fuel delivery mechanisms to mitigate risks under load. Such modifications extended the engine's from an initial 100 hours and enhanced overall robustness without compromising the water-cooled V-12 architecture. The inaugural series production unit was delivered later that year, initiating widespread adoption in German .

Record-setting achievements

The BMW VI engine demonstrated exceptional reliability in extreme conditions during pioneering long-distance flights, particularly through its use in Dornier Wal flying boats led by Wolfgang von Gronau, which helped validate northern transatlantic routes via and . In August 1930, von Gronau completed the first east-to-west in a flying boat, piloting the Dornier Wal D-1422—equipped with two BMW VI engines—from Lake Müllersee near to New York, covering approximately 6,000 km over five days with stops in and for refueling and exploration. This feat, conducted under the auspices of the German aviation organization, highlighted the engine's sustained power output during prolonged overwater operations in harsh weather. The following year, in 1931, BMW VI-powered Dornier Wals contributed to polar expedition flights, including von Gronau's route from , , to Labrador via , where the engines enabled detailed aerial surveys of ice fields and potential air corridors, advancing scientific understanding of navigation challenges. BMW VI engines also supported speed-oriented achievements, for example the Heinkel HE 9 set a of 222 km/h over 1,000 km in 1929, underscoring the engine's versatility beyond endurance roles. The pinnacle came in 1932 with von Gronau's circumnavigation of the globe—the first by a flying boat—aboard the Dornier Wal D-2053 "Grönland Wal," fitted with two BMW VI 7.3z variants. Departing , the 44,000 km journey spanned 146 flying hours over four months, routing through the , , , , and the before returning to , proving the engine's durability across diverse climates and altitudes.

Production and licensing

German manufacturing

Series production of the BMW VI engine commenced in 1926 following its type approval, establishing it as a cornerstone of BMW's output at the company's primary facility in . The engine powered both commercial airliners and while achieving export success, which bolstered BMW's position in the interwar sector. Approximately 9,200 units were produced in between 1926 and 1938. Production continued steadily through the early , with the company's workforce expanding from 6,514 employees in 1933 to over 26,000 by 1939 amid rising demand driven by 's rearmament efforts. To meet escalating production needs, opened a dedicated plant in Munich-Allach in 1936, funded in part by government initiatives through the Luftfahrtkontor ; this facility was designed with features as a "shadow factory" to enhance security. An additional site in Eisenach-Dürrerhof followed in 1937, further scaling output for components, though the itself was phased out that year in favor of newer air-cooled designs like the and BMW 801. Manufacturing emphasized precision engineering typical of the era, including robust construction for the water-cooled V-12 configuration derived from the earlier BMW IV, with each unit undergoing rigorous testing to ensure reliability for demanding flight applications. The BMW VI's success played a pivotal role in BMW's economic stability and diversification, with revenues from aviation engine production rising from 35.56 million Reichsmarks in 1933 to 275.5 million by 1939, enabling the company to enter automobile production in 1928 and expand beyond . This shift was crucial during the , as engine sales provided the financial foundation for BMW's transition into a multifaceted mobility manufacturer, sustaining operations through economic challenges and positioning the firm for postwar recovery.

Licensed production abroad

The BMW VI engine was licensed to the through an agreement signed on October 14, 1927, between General Director F. Popp and Aviatrust Chairman M. G. Urivayev, for a lump sum of $50,000 plus 7.5% royalties per engine. Production of the licensed version, designated , began in 1930 at State Aviation Plant No. 26 in , following initial assembly efforts at Factory No. 24 in , where three engines were completed that year. By the end of 1930, 165 M-17 engines had been produced at , rising to 679 in 1931, with the plant modernized for an annual output of 500 units in peacetime and up to 1,000 during wartime. In total, 27,534 M-17 engines across various modifications were manufactured until 1942, making it one of the most prolific licensed derivatives of the BMW VI. Technical transfers under the Soviet license included blueprints and expertise for key components such as superchargers and carburetors, along with on-site support from German engineers and suppliers like Bosch and for casting methods and parts. These enabled local innovations, including the M-17F variant, which achieved 750 PS output through enhanced supercharging and improved fuel systems. In , acquired the license for the VI in , initiating production of the Ha-9 ( Type 98 850 hp Liquid-Cooled Inline) in 1930 at their factory. Approximately 2,000 Ha-9 engines were built, serving primarily in Imperial Japanese Army Air Service aircraft during the 1930s. Limited licensing efforts occurred in other European countries during the 1930s. In Czechoslovakia, the Walter company produced BMW VI engines under license from the early 1920s onward, though output remained modest and focused on integration into local airframes amid shifting political conditions.

Variants

Standard BMW VI variants

The standard variants of the BMW VI engine were baseline configurations optimized for low- to medium-altitude operations in civil and military aircraft during the interwar period. These models differed mainly in compression ratios, which directly influenced power output, fuel efficiency, and suitability for specific roles, while sharing core design elements such as a 45.8-liter displacement from a 160 mm bore and 190 mm stroke, a two-speed supercharger with gear ratios of 7.8:1 (low) and 11.2:1 (high) for manual engagement above 2,500 meters, and Zenith carburetors for fuel delivery. Geared models like the BMW VI U featured 1.6:1 reduction for propeller speeds, with dry weights around 544 kg. The BMW VI 5.5 featured a 5.5:1 , delivering 600–650 PS (approximately 592–641 hp) at 1,500 rpm, with a dry weight of 495 kg. It was primarily employed in early civil transports, offering reliable performance for and cargo operations at without specialized high-altitude tuning. Introduced in 1928, the BMW VI 6.0 had a 6:1 and produced 630–660 PS (621–651 hp), providing improved over the 5.5 variant while maintaining similar operational characteristics. This model found application in medium bombers, balancing power and economy for tactical missions. The BMW VI 7.3u served as the base high-compression model with a 7.3:1 ratio, rated at 680 PS takeoff power and a specific consumption of 240 g/PS/h. It became the standard powerplant for transports like the , emphasizing durability and efficiency in multi-role .

High-altitude and special variants

The BMW VI 7.3z variant featured a 7.3:1 and a gear-driven high-altitude designed to sustain performance in thin air, delivering 750 horsepower at takeoff. The engine powered early fighters such as the He 51B-3 high-altitude reconnaissance model and early prototypes of the , where it provided reliable output for operations above 4,000 meters. Integration with variable-pitch propellers, such as three-bladed units on installations, optimized thrust vectoring and climb rates. These adaptations underscored the engine's versatility for specialized roles beyond standard atmospheric conditions.

Licensed foreign variants

The was the primary Soviet adaptation of the BMW VI under license, initiated in 1927 and entering production in 1930 at the plant, where over 27,000 units were manufactured through 1942. This V-12 liquid-cooled engine retained the original's core architecture but incorporated Soviet techniques to suit local materials and operational demands, evolving into a family of variants with power outputs ranging from 500 to 730 horsepower depending on configuration. The base M-17 delivered approximately 600 horsepower at sea level, while the M-17B variant achieved 680 horsepower through refined tuning. Further developments included the M-17R at 730 horsepower with a 7.3:1 , emphasizing reliability for extended service in diverse conditions. Subsequent Soviet variants built on the M-17 foundation for specialized roles. The M-17F, produced into the 1940s, enhanced durability to 300 hours of service life compared to the original's 100 hours, maintaining around 730 horsepower for sustained wartime applications. The M-17A targeted use with optimizations for reduced complexity, outputting 500 horsepower at takeoff and weighing 540 kilograms dry. In , produced the Ha-9 series as a licensed derivative of the BMW VI starting in 1927, manufacturing over 2,000 units by 1940 to meet and Navy requirements. This 45.8-liter V-12 liquid-cooled engine was adapted with modifications for regional fuel availability and environmental factors, including sea-level tuning in early models. The Ha-9-I and Ha-9-II variants delivered 600 horsepower, optimized for low-altitude operations in naval and roles. The Ha-9-IIa advanced this with 850 horsepower at takeoff, incorporating supercharging for 950 horsepower at 3,800 meters to enhance climb rates in fighter prototypes. Later Japanese iterations of the Ha-9 emphasized experimental enhancements for power and durability. The Ha-9-III maintained the series' displacement while refining metallurgy for better heat dissipation, achieving consistent 800-horsepower outputs in production applications. These adaptations highlighted Kawasaki's focus on integrating the BMW VI design with indigenous alloys to resist corrosion in humid, maritime environments.

Applications

Military aircraft

The BMW VI engine played a significant role in powering early Luftwaffe combat aircraft during the rearmament period of the 1930s, particularly in medium and fast bombers where its reliable 660–750 hp output supported rapid development of tactical platforms. Its liquid-cooled V-12 design allowed for compact nacelles, contributing to streamlined fuselages that enhanced aerodynamic performance in high-speed designs. Although production emphasized versatility for both military and civil roles, the engine's adoption in frontline units underscored Germany's push toward modern air forces under treaty restrictions. One key application was the "Flying Pencil," a renowned for its slender profile and speed. Early variants, such as the Do 17E-1, were fitted with two BMW VI 7.3 V-12 engines, each delivering 750 hp, which propelled the aircraft to a top speed exceeding 350 km/h at altitude while carrying up to 750 kg of bombs. This performance made the Do 17 a cornerstone of the Luftwaffe's doctrine, emphasizing evasion through velocity rather than heavy armor, with over 300 such aircraft entering service by the late 1930s. The engine's integration here highlighted its suitability for narrow fuselages, though cooling challenges in tropical climates later prompted shifts to radial alternatives. The also relied on the BMW VI in its formative stages, with the initial V1 prototype and early A-series production models equipped with two BMW VI 6.0Z units rated at 660 hp each. These powered the to operational speeds suitable for roles, influencing the design's evolution into a versatile platform used in and adaptations. A batch of 10 early He 111A incorporated the engine before production transitioned, reflecting its transitional importance in bridging pre-war prototypes to wartime standards. Beyond , the BMW VI's licensed production as the Kawasaki Ha-9 extended its military footprint in Axis-aligned forces. The Imperial Japanese Army's fighter, introduced in 1935, utilized the Ha-9-IIa variant, a direct adaptation providing 850 hp for takeoff, which enabled agile dogfighting in early Sino-Japanese conflicts. This upright V-12 configuration armed with synchronized machine guns marked the Ki-10 as Japan's last fighter, with around 300 units produced before successors rendered it obsolete. The Soviet-licensed variant powered numerous Red Army aircraft, including the Polikarpov I-3 fighter and heavy bomber, with production exceeding 27,000 units supporting interwar . In operational service, the BMW VI facilitated speeds over 300 km/h in platforms like the Do 17, proving effective for in the early war years, though its installations in military aircraft are estimated in the thousands amid total global production exceeding 9,000 units by 1938. By the mid-1930s, however, escalating demands for greater power output led to its phasing out in favor of advanced inverted V-12s like the , which offered 1,000+ hp for evolving bomber requirements in designs such as later He 111 variants.

Civil and experimental uses

The BMW VI engine powered several civil , notably the flying boat, which served on commercial passenger and mail routes across , , and during the 1920s and 1930s. Variants such as the Do J IIa Bos Wal and Do J IIaK Bos Wal, equipped with two BMW VI engines each producing around 600 hp, enabled long-range operations, including Deutsche Luft Hansa's South Atlantic airmail service from 1934 to 1938, where they completed over 300 crossings between Bathurst, , and , , carrying up to 1,000 kg of mail over distances of 3,600 km. These aircraft, operated by airlines like SANA (), Aero Espresso (), and (), demonstrated the engine's reliability for non-military maritime aviation, with a service ceiling of 3,500 m supporting safe overwater flights. The W.33 also utilized the BMW VI in select configurations for exploratory missions, including polar expeditions that tested the engine's performance in extreme cold, contributing to advancements in long-distance civil during the late . Beyond aviation, the BMW VI saw innovative experimental applications, most prominently in the , a propeller-driven developed by Franz Kruckenberg, which in reached a world railway speed record of 230 km/h (143 mph) on the Berlin-Hamburg line using a single BMW VI 12.0z variant delivering 600 hp. This non-aerodynamic experiment highlighted the engine's adaptability to ground-based propulsion, achieving the feat between Karstädt and Dergenthin without conventional rail wheels for traction. In automotive experiments, the BMW VI powered the Brutus, a custom built on a pre-World War I American LaFrance fire truck chassis in the late 1920s and tested through for land speed attempts, where its 750 hp output enabled high-velocity runs on closed courses, influencing early aero-engine-to-automotive concepts. The licensed Soviet M-17 derivative of the BMW VI supported post-war civilian operations, including mail services in remote regions through the . Early record flights further showcased the engine's endurance in exploratory .

Specifications

General characteristics (BMW VI 7.3z)

The BMW VI 7.3z is a 60° V-12, four-stroke, liquid-cooled piston engine designed for applications. It features 12 arranged in two banks of six, with a single overhead per bank driving two valves per . Key dimensional specifications include a bore of 160 mm and a stroke of 190 mm, though some late-production models incorporated a longer stroke of 199 mm on one bank to optimize . The resulting displacement is 46,882 cm³ (46.9 L). Overall dimensions are a length of 1,810 mm, width of 859 mm, and height of 1,100 mm. The dry weight is 510 kg, increasing to 590 kg when filled with fluids. It operates on 87-octane supplied via dual carburetors.

Components

The BMW VI 7.3z employed an aluminum to support its V-12 layout, providing a lightweight yet robust structure for the engine's internal components. The cylinders were constructed from with integrated wet liners, allowing for efficient heat transfer to the surrounding and contributing to the engine's overall under high-load conditions. These material choices balanced weight reduction with the mechanical stresses of use, as seen in licensed productions and applications. The cooling system was liquid-based, relying on a driven by the to circulate water through the jackets and . This setup ensured consistent thermal management, with the accommodating approximately 120 L of to handle the heat generated during operation at temperatures ranging from 80 to 90°C. Such design prevented overheating in demanding flight profiles while minimizing drag through optimized over the radiator surfaces. Fuel delivery was managed by dual 60 DCL carburetors, which mixed air and for optimal efficiency across varying altitudes and throttle settings. The utilized dual magnetos—one from Bosch and one from Scintilla—for redundancy and reliability, with a separate injection mechanism facilitating cold starts by directly introducing into the cylinders. This combination enhanced starting reliability and reduced the risk of ignition failure in operational environments. The incorporated sodium-filled exhaust valves to aid in heat dissipation from the , paired with valves operated via a single overhead per bank for precise timing and reduced valvetrain mass. was provided by a oil system with a 40 L capacity, where a circulated oil under 4-6 bar pressure to critical components like bearings and gears, ensuring and minimizing oil starvation during maneuvers.

Performance

The BMW VI 7.3z produced a maximum takeoff power of 750 PS (552 kW) at 1,700 rpm, enabling strong initial acceleration in equipped . For sustained operation, it delivered 690 PS in maximum continuous mode at 1,650 rpm, with power dropping at altitude due to atmospheric conditions as a . Specific consumption varied by operating condition, reaching approximately 300 g/kWh during takeoff for high-power demands, while 313 g/kWh in cruise settings for better . Operational limits encompassed a peak RPM of 1,700 for short durations and 1,650 for continuous use, supporting service ceilings up to 7,000 m through reliable high-altitude performance. Key efficiency metrics highlighted the engine's engineering balance, with a power-to-weight ratio of 1.47 PS/kg based on its 510 kg dry mass and takeoff rating. approximated 30% under takeoff loads, achieved via the 7.3:1 that optimized without excessive knock on period fuels.

References

  1. https://www.enginehistory.org/Piston/Before1925/EarlyEngines/B/B.shtml
  2. http://airpages.ru/eng/ru/m17.shtml
  3. http://pwencycl.kgbudge.com/H/a/Ha-9_aircraft_engine.htm
  4. https://www.uniquecarsandparts.com/history_bmw_aero.htm
  5. https://www.press.bmwgroup.com/global/photo/detail/P0034943/%25C2%25BFrail-zeppelin%25C2%25BF-with-bmw-vi-aero-engine-which-reached-a-speed-of-230-km/h-on-the-berlin-hamburg-route-in-1931-03/2007?language=en
  6. https://sinsheim.technik-museum.de/en/brutus
  7. https://www.press.bmwgroup.com/global/article/detail/T0257819EN/bmw-group-classic-presents-bmw-100-years-of-engine-and-motorsport-excellence?language=en
  8. https://aeroenginesaz.com/en/brand_bmw-part-1
  9. https://www.youtube.com/watch?v=6GyEtepuNDo
  10. https://www.press.bmwgroup.com/asia/article/detail/T0257936EN/the-history-of-the-bmw-group:-100-years-of-fascination-for-mobility?language=en
  11. https://airandspace.si.edu/stories/editorial/wolfgang-von-gronau-and-his-greenland-whales
  12. https://time.com/archive/6749688/aeronautics-again-von-gronau/
  13. https://www.cambridge.org/core/journals/polar-record/article/commander-von-gronaus-flight-1931-a-photographic-record/AB56B69B827AEE07FF73CF9CC84DAE2B
  14. https://www.emerald.com/insight/content/doi/10.1108/eb029248/full/pdf
  15. https://www.press.bmwgroup.com/canada/article/attachment/T0135207EN/204671
  16. https://www.press.bmwgroup.com/global/article/detail/T0257819EN/the-history-of-the-bmw-group:-100-years-of-fascination-for-mobility?language=en
  17. https://www.bmwgroup.com/en/company/history/BMW-during-the-era-of-national-socialism.html
  18. https://ww2aircraft.net/forum/threads/bmw-vii-viii-successors-of-bmw-vi.36852/
  19. https://www.warbirdsresourcegroup.org/LRG/luftwaffe_heinkel_he51.html
  20. https://histaviation.com/do-17-e.html
  21. https://aeroenginesaz.com/en/brand_mikulin
  22. https://www.aircraftinvestigation.info/airplanes/Mikulin_M.17.html
  23. https://www.armedconflicts.com/Mikulin-M-17-t125734
  24. https://www.redstar.gr/en/russian-aerial-means/aero-engines/mikulin-m-17a-piston-engine.html
  25. https://aeroenginesaz.com/en/brand_kawasaki
  26. https://www.classicwarbirds.co.uk/german-aircraft/heinkel-he-111.php
  27. https://battleofbritain1940.com/german-aircraft-of-the-battle-of-britain/dornier-do-17/
  28. https://www.militaryfactory.com/aircraft/detail.php?aircraft_id=292
  29. https://airpages.ru/eng/lw/do17e.shtml
  30. https://rwebs.net/ghostsqd/He111.htm
  31. https://www.gruppofalchi.com/files/Profile-Publications-Aircraft-015---Heinkel-He111H.pdf
  32. https://airpages.ru/eng/jp/ki10.shtml
  33. https://www.military-history.fandom.com/wiki/BMW_VI
  34. https://encyclopedia.pub/entry/28783
  35. https://oldmachinepress.com/2021/03/05/rail-zeppelin-propeller-driven-railcar-schienenzeppelin/
  36. https://vintageaviationnews.com/aviation-museum-news/brutus-bmw-vi-aero-engine-car-to-feature-at-brazzeltag.html
  37. https://www.aircraftinvestigation.info/airplanes/BMW_VI_7.3z_info.html
  38. https://military-history.fandom.com/wiki/BMW_VI
  39. https://www.press.bmwgroup.com/global/article/attachment/T0257819EN/354550
  40. https://www.hemmings.com/stories/schiene-zeppelin/
  41. https://www.quora.com/What-led-to-the-decision-to-re-engine-Japanese-aircraft-like-the-Ki-61-and-D4Y-with-radial-engines-and-how-did-this-affect-their-performance
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