Tennessee and her sister ship California were the first American battleships built to a "post-Jutland" hull design. As a result of extensive experimentation and testing, her underwater hull protection was much greater than that of previous battleships; and both her main and secondary batteries had fire-control systems. The Tennessee class, and the three ships of the Colorado class which followed, were identified by two heavy cage masts supporting large fire-control tops. This feature was to distinguish the "Big Five" from the rest of the battleship force until World War II. Since Tennessee's 14-inch turret guns could be elevated to 30 degrees - rather than to the 15 degrees of earlier battleships - her heavy guns could reach out an additional 10,000 yards. Because battleships were then beginning to carry airplanes to spot long-range gunfire, Tennessee's ability to shoot "over the horizon" had a practical value.