New Mexico - class battleship The " New Mexico " - class battleships of the United States Navy , all three of whose construction began in 1915 , were improvements on the design introduced three years earlier with the . The twelve - gun main battery of the preceding was retained , but with longer 50 caliber guns in improved triple turrets . Hull design was also upgraded with a ' clipper ' bow for better seakeeping and a sleeker look . One ship , the , was fitted with turbo - electric propulsion . Though eight secondary batteries were located in extremely wet bow and stern positions and were soon removed , the rest of the ships ' guns were mounted in the superstructure , a great improvement over earlier U . S . Navy battleships ' arrangements . Class history . Completed during and soon after World War I , the " New Mexico " s were active members of the Battle Fleet during the decades between the World Wars . All were rebuilt between 1931 and 1934 , receiving entirely new superstructures , modern controls for their guns , new engines and improved protection against air and surface attack . Anti - torpedo bulge s increased their width to and displacement went up by a thousand tons or more . The " New Mexico " class was part of the standard - type battleship concept of the U . S . Navy , a design concept which gave the Navy a homogeneous line of battle ( it allowed planning maneuvers for the whole line of battle rather than detaching " fast " and " slow " wings ) . The standard - type battleship concept included long - range gunnery , moderate speed of , a tight tactical radius of and improved damage control . The other standard - type battleships were the , , , and es . In order to counter the German threat , these ships — operating together as Battleship Division 3 — were transferred from the Pacific to the Atlantic in 1941 , leaving the U . S . Pacific Fleet inferior in battleship strength to the Japanese Navy . Sent back to the Pacific after the Pearl Harbor raid devastated the Pacific Fleet ' s powerful battle line , they were active in the war with Japan until final victory was achieved in August 1945 . Their heavy guns provided vital assistance to the many amphibious invasion s that marked the Pacific conflict , and " Mississippi " took part in the Battle of Surigao Strait , the last time in history that battleships fought each other . " New Mexico " and " Idaho " were disposed of soon after the war ended , but " Mississippi " was converted to a training and weapons trials ship and served for another decade . The U . S . Navy ' s first generation of ship - launched guided missile s went to sea aboard this old former battleship . Design history . Designated as Battleship 1916 , the design history is marked by the incipient test firing of the 16 " U . S . naval gun . The gun promised to deliver twice the energy of a 12 " gun and 1 . 5 times the energy of a 14 " gun . The problem was that the 16 " gun was not tested . If the gun failed then the design would have to wait for new 14 " turrets to be fabricated . The first design offered to C & R was no less than 10 16 " guns and 8 torpedos . The design also included upgrading the armor as well as extending it . A secondary battery of 6 " guns was incorporated into the design . The General Board arguing that the increasing range of torpedos required the increase of caliber . In August 1914 the 16 " gun was successfully test fired silencing that question but that would happen after the design was in front of SecNav . The rise in displacement and the rise in the cost of the new design presented issues . The General board pushed for the advancement with C & R wanting to repeat the Pennsylvania Class . Both the Secretary of the Navy Josephus Daniels and the House of Representatives rose up against the cost . The General Board was convinced that the major sea powers would jump to 15 " or 16 " naval guns as a main armament and asked for designs based on the 16 " gun . A series of designs was laid out with the last being a design with 8 16 " guns on the 31 , 000 ton design of the earlier Pennsylvania design . No one reviewing the design was at all happy with it . Strangely enough , it would except in small details , become the blueprint of the Maryland Class Battleships . On July 30 , the Secretary of the Navy ordered that , except for the inclusion of individual slides for the main guns , the Tennessee Class would be a reproduction of the preceding Pennsylvania Class . References . Initially based on the public domain article published by the Department of the Navy ' s Naval Historical Center