The BK 27 (also BK27 or BK-27) (German acronym for "Bordkanone": transported cannon) is a 27mm automatic cannon manufactured by Mauser (now part of Rheinmetall). It was developed in the late 1960s for the MRCA (Multi-Role combat Aircraft) program that would eventually become the Panavia Tornado. Mauser BK-27 in International Aerospace Exhibition (ILA) of 2006.
The Mauser BK 27 is used in the Panavia Tornado, the Alpha Jet, the Saab 39 Gripen and the Eurofighter Typhoon. Initially the Air Force of the United States wanted to produce this weapon under license for the F-35 but those plans seem to have been canceled in favor of the GAU-12.
There are naval versions, MN 27 GS and MLG 27, used on many ships of the German Navy.
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