 Like most battleships in World War II, the Montana class would have been equipped with a fire control computer, in this case the Ford Mk 1A Ballistic Computer, a 3,150 lb (1,430 kg) rangekeeper designed to direct gunfire on land, sea, and in the air. This analog computer would have been used to direct the fire from the battleship's big guns, taking into account several factors such as the speed of the targeted ship, the time it takes for a projectile to travel, and air resistance to the shells fired at a target. At the time the Montana class was set to begin construction, the rangekeepers had gained the ability to use radar data to help target enemy ships and land-based targets. The results of this advance were telling: the rangekeeper was able to track and fire at targets at a greater range and with increased accuracy, as was demonstrated in November 1942 when the battleship Washington engaged the Imperial Japanese Navy battleship Kirishima at a range of 18,500 yd (16.9 km) at night; the Washington scored at least nine heavy caliber hits that critically damaged the Kirishima and led to her loss. This gave the US Navy a major advantage in World War II, as the Japanese did not develop radar or automated fire control to the level of the US Navy.
