Post-Panamax

Post-Panamax and Post-Neopanamax ships

Post-Panamax or over-Panamax denote ships larger than Panamax that do not fit in the original canal locks, such as supertankers and the largest modern container and passenger ships. The first post-Panamax ship was the RMS Queen Mary, launched in 1934, built with a 36 m (118 ft) beam as she was intended solely for North Atlantic passenger runs. When she was moved to Long Beach, California, as a tourist attraction in 1967, a lengthy voyage around Cape Horn was necessary. The first post-Panamax warships were the Japanese Yamato-class battleships, launched in 1940. Until World War II, the United States Navy required that all of their warships be capable of transiting the Panama Canal. The first US Navy warship design to exceed Panamax limits was the Montana-classbattleship, designed circa 1940 but never built. The limit was specifically removed by the Secretary of the Navy on 12 February 1940, with the (never-realized) prospect of a new set of 43 m (140 ft) wide locks to be built for the Canal. The Essex-classaircraft carriers were designed with a folding deck-edge elevator to meet Panamax limits; the limit did not apply to subsequent US aircraft carriers.