{{Short description|Aircraft engine family by BMW}} {{Nofootnotes|date=April 2018}} <!-- This article is a part of Wikipedia:WikiProject Aircraft. Please see Wikipedia:WikiProject Aircraft/page content for recommended layout. --> {{infobox aero engine |name = BMW VI |image = File:BMW VI Berlin 02.jpg |caption = BMW VI at the Technik-Museum Berlin |engine_type=V12 engine |manufacturer=BMW |national_origin= |first_run= 1926 |major_applications= {{ubl | Heinkel He 51 | Kawasaki Ki-10 }} |number_built = |developed_from = BMW IV |variants_with_their_own_articles = |developed_into = {{ubl | BMW VII | Mikulin M-17 }} }}
The '''BMW VI''' was a water-cooled V12 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== thumb|left|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== '''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).
thumb|BMW VI at the Technik-Museum Berlin ;BMW VI 5.5 : Compression ratio 5.5:1, {{convert|600-650|PS|hp|abbr=on|sigfig=3}} at up to 1600 rpm at sea level ;BMW VI 6.0 : Compression ratio 6:1, {{convert|630-660|PS|hp|abbr=on|sigfig=3}} at up to 1650 rpm at sea level, 80 Octane fuel ;BMW VI 7.3 : Compression ratio 7.3:1 {{convert|680-750|PS|hp|abbr=on|sigfig=3}} at up to 1700 rpm at sea level, 87 Octane fuel ;Mikulin M-17: {{Main|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== thumb|BMW VI head detail {{div col|colwidth=30em}} * Albatros L 77v * Arado Ar 64 * Arado Ar 65 * Arado Ar 68 * Arado SSD I * Brutus (car) * Dornier Do 10 * Dornier Do 14 * Dornier Do 17 * Focke-Wulf Fw 42 * Heinkel He 45 * Heinkel He 51 * Heinkel He 59 * Heinkel He 60 * Heinkel He 70 * Heinkel He 111 prototype and civilian versions * Junkers F.24ko * Kawasaki Type 92 * Kawasaki Ki-10 * Messerschmitt M.20 * Polikarpov R-5 prototype * Schienenzeppelin * Tupolev TB-3 {{col div end}}
==Specifications (BMW VI 7.3z)== thumb|Side view of the BMW VI {{pistonspecs| <!-- If you do not understand how to use this template, please ask at Wikipedia talk:WikiProject Aircraft --> <!-- Please include units where appropriate (main comes first, alt in parentheses). If data are missing, leave the parameter blank (do not delete it). For additional lines, end your alt units with )</li> and start a new, fully formatted line with <li> --> |ref=''Flugzeug-Typenbuch. Handbuch der deutschen Luftfahrt- und Zubehör-Industrie 1944'' <ref name=schneider>{{cite book |last=Schneider |first=Helmut (Dipl.Ing.) |title=Flugzeug-Typenbuch. Handbuch der deutschen Luftfahrt- und Zubehör-Industrie 1944 |date=1944 |publisher=Herm. Beyer Verlag |location=Leipzig |isbn=381120484X |edition=Facsimile reprint 1986 |language=German |page=365}}</ref> |type= V12, 60° water-cooled piston engine |bore={{convert|160|mm|in|2|abbr=on}} |stroke={{convert|190|mm|in|2|abbr=on}} / {{convert|199|mm|in|2|abbr=on}} (different between right and left cylinder bank due to articulated connecting rods). |displacement={{cvt|46.9|L|cuin|2}} |length={{convert|1810|mm|in|2|abbr=on}} |diameter= |width={{convert|859|mm|in|2|abbr=on}} |height={{convert|1103|mm|in|2|abbr=on}} |weight={{convert|510|kg|lb|0|abbr=on}} |valvetrain=1 inlet + 1 exhaust valve per cylinder operated by a shaft driven overhead camshaft via rockers |supercharger= |turbocharger= |fuelsystem=2 x Zenith 60 DCL |fueltype=min. 87 octane gasoline |oilsystem= |coolingsystem=Liquid-cooled |power=<br> :*{{cvt|750|PS|hp kW|0}} for takeoff at 1,700 rpm (1 minute) at sea level :*{{cvt|690|PS|hp kW|0}} at 1,650 rpm (5 minutes) at sea level :*{{cvt|620|PS|hp kW|0}} at 1,590 rpm (30 minutes) at sea level :*{{cvt|550|PS|hp kW|0}} at 1,530 rpm (max. duration) at sea level |specpower={{cvt|16|PS/L|hp/cuin kW/L|2}} |compression=7.3 |fuelcon= |specfuelcon=<br> :*{{cvt|0.23|kg/PSh|lb/hph kg/kWh|3}} at 1,590 rpm :*{{cvt|0.225|kg/PSh|lb/hph kg/kWh|3}} at 1,530 rpm |oilcon={{cvt|0.003|-|0.01|kg/PSh|lb/hph kg/kWh|3}} at 1,530 rpm |power/weight={{cvt|1.47|PS/kg|hp/lb kW/kg}} *'''B.M.E.P.:''' {{cvt|6.9|atm|bar psi}} |designer= |reduction_gear=none
|general_other= |components_other= |performance_other= }}
==See also== {{aircontent <!-- other related articles that have not already linked: --> |see also=
<!-- designs which were developed into or from this aircraft: --> |related= * BMW IV * BMW VII * Mikulin M-17 <!-- aircraft that are of similar role, era, and capability this design: --> |similar aircraft=
<!-- relevant lists that this aircraft appears in: --> |lists= * List of aircraft engines <!-- For aircraft engine articles. Engines that are of similar to this design: --> |similar engines= * Liberty L-12 <!-- See WP:Air/PC for more explanation of these fields. --> }}
==References== {{reflist}}
==Further reading== {{commons category|BMW VI}} * {{cite book |last= Gunston |first= Bill |title=World Encyclopedia of Aero Engines |year=1986 |publisher=Patrick Stephens |location= Wellingborough |page=25 |ref=Gunston, Encyc. Aero Engines }}
{{BMW aeroengines}} {{Japanese Imperial Army aeroengines}}
Category:BMW aircraft engines Category:1920s aircraft piston engines Category:V12 aircraft engines Category:Liquid-cooled aircraft piston engines