From the day the Panama Canal opened in 1914, America has relied upon the Canal to quickly shift military vessels from one coast to the other. But the Canal also imposed an unalterable rule in U.S. naval vessel design. Most naval ships simply had to fit through the canal. The original Panama Canal dimensions were immutable; Navy ships were built to comply with the canal’s original 320 meter length, 33.53 meter width, and 12.56 meter depth limitations, as well as meet a height constraint imposed by the Bridge of the Americas at Balboa.
From the early 1900’s, U.S. Navy ship designers toiled to cram as much combat power as possible through the Panama Canal’s locks. America’s massive, 45,000-ton Iowa-class battleships, built at the height of World War II, were so big they they had only mere inches of clearance on either side of the canal. America didn’t dare to defy the Panama Canal restrictions until until 1945, with the commissioning of the first Midway-class aircraft carriers.
Today, only America’s biggest and most valuable surface combatants (aircraft carriers and big-deck amphibious vessels) are permitted to exceed the design constraints imposed by the Panama Canal.
In mid-2016, new locks opened the canal to ships as large as 427 meters in length, 55 meters in width and 18.3 meters in depth. Today, supersized container ships, tankers and passenger ships use the new locks to move between the Pacific and the Atlantic Oceans.