B39 or B-39 may refer to:
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Bundesstraße 39, a German road
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B39 nuclear bomb
The Mark 39 nuclear bomb and W39 nuclear warhead were versions of an American thermonuclear weapon, which were in service from 1957 to 1966.
The Mark 39 design was a thermonuclear bomb (see Teller-Ulam design) and had a yield of 3.8 megatons. ...
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XB-39 Superfortress
The Boeing XB-39 Superfortress was a United States prototype bomber aircraft, a single example of the B-29 Superfortress converted to fly with alternative powerplants. It was intended to demonstrate that the B-29 could still be put into service ...
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Soviet submarine B-39
''B-39'' was a Project 641 () diesel-electric attack submarine of the Soviet Navy. The "B" (actually " Б") in her designation stands for большая (''bolshaya'', "large")—Foxtrots were the Soviet Navy's largest non-nuclear submarines.
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, a Foxtrot class submarine
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HLA-B39, an HLA-B serotype
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B39 (New York City bus)
The Metropolitan Transportation Authority (MTA) operates a number of bus routes in Brooklyn, New York (state), New York, United States; one minor route is privately operated under a city government-granted monopoly, franchise. Many of them are th ...
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