MW 50 was a 50-50 mixture of methanol and water (thus the name) that was sprayed into the supercharger of German aircraft engines primarily for its anti-detonant effect, allowing the use of increased boost pressures. Secondary effects were cooling of the engine and charge cooling. Higher boost was only effective at altitudes below the full throttle height where the supercharger could provide additional boost pressure, while the smaller secondary effects were useful even above that altitude. Methanol, also known as methyl alcohol or wood alcohol, is a chemical compound with chemical formula CH3OH. It is the simplest alcohol, and is a light, volatile, colourless, flammable, poisonous liquid that is used as an antifreeze, solvent, fuel, and as a denaturant for ethyl alcohol. ... Water (from the Old English word wæter; c. ... A supercharger (also known as a blower, a positive displacement pump or a centrifugal pumper) is a gas compressor used to pump air into the cylinders of an internal combustion engine. ... The term aircraft engine, for the purposes of this article, refers to aircraft reciprocating, or rotary, internal combustion engines as opposed to jet engines or turboprops. ...

MW 50 is something of a misnomer, as it is actually a mixture of three fluids; 50% methanol acting primarily to achieve optimum anti-detonant effect, secondarily as an anti-freeze, 49.5% water, and 0.5% Schutzöl 39, an anti-corrosion additive. The similar MW 30 increased the water to 69.5 and decreased methanol to 30%. This increased the cooling performance but made it easier to freeze, intended to be used for lower-altitude missions.

The effect of MW 50 injection could be dramatic. Simply turning on the system allowed the engine to pull in more air, boosting performance about 100 hp on the BMW 801. However the MW 50 also allowed the supercharger to be run at much higher boost levels as well, for a combined increase of 500hp. MW 50 was fully effective up to about 6,000 m, above which it added only about 4% extra power. The BMW 801 was a powerful German air-cooled radial aircraft engine built by BMW and used in a number of German military aircraft of World War II. The engine’s cylinders were in two rows of seven cylinders each, the bore and stroke were both 156 mm, giving a...

Aircraft generally carried enough MW 50 for about 10 minutes of use, allowing them to increase their climb rate for interception missions. Fittings for MW 50 first appeared on the BMW 801D in 1942, but it never went into production for this engine because the cylinder heads developed micro-cracks when MW 50 was used. Instead, the DB 605-engined Messerschmitt Bf 109 was fitted with an MW 50 injection system. Later engines designs all included the fittings as well, notably the Junkers Jumo 213, which relied on it in order to reduce non-boosted performance and tune the supercharger for higher altitudes. Interceptor has several meanings: Bearcat interceptor Interceptor was a TV series that ran in the UK during 1989. ... (Bf 109 was the official Reichsluftfahrtministerium designation, since the design was sent in by the Bayerische Flugzeugwerke company. ... The Jumo 213 was a World War II-era V-12 liquid cooled aircraft engine, a development of Junkers Motorens earlier design, the Jumo 211. ...

MW 50 was not the only charge cooling system to be used by the Germans. Some engines dedicated to high altitude included an intercooler instead, as they would be needing the cooling for longer periods of time. The 801D also included the ability to spray gasoline into the supercharger, in place of the MW 50, and while this was not as effective it did increase boost without the complexity of the additional tanking and plumbing. Additionally many of the late-war engines also included a system for high-altitude boost, GM 1, which was intended to add oxygen instead of improve boost levels. GM-1 was a system for injecting nitrous oxide into aircraft engines that was used by the Luftwaffe in World War II to boost the high-altitude performance of their aircraft. ...