Oriskany, which had been left unfinished at the end of the war, was completed to an improved design between August 1948 and September 1950, with a much stronger (straight) flight deck and a reconfigured island. Eight earlier ships were thoroughly rebuilt to the Oriskany design under the SCB-27A program in the early 1950s. Six more of the earlier ships were rebuilt to an improved 27C design as the last stage of the SCB-27 program; these ships received steam catapults instead of the less powerful hydraulic units. The otherwise unmodified Antietam received an experimental 10.5-degree angled deck in 1952. An angled flight deck and enclosed hurricane bow became the distinctive features of the SCB-125 program, which was undertaken concurrently with the last three 27C conversions and later applied to all 27A and 27C ships except Lake Champlain. Shangri-La became the first operational United States angled deck aircraft carrier in 1955.
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