In Naval Aviaton, the post war Essex class carriers, heavily modified from their original design, were often colloquially referred to as 27C, pronounced “twenty seven charlie.”
The term came from the Ship Characteristics Board, or SCB, which not surprisingly, laid out the characteristics for Navy ships. Each series of designs would have a numerical designation, often with a letter suffix.
Though the Essex class carriers were often called 27C, in fact, there were a wide variety of modifications applied to the class postwar. The last Essex carrier in service was USS Oriskany, decommissioned in 1976.
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