U.S. Military Battleships

U.S. Atlantic Fleet


One of our P-3Bs overflying the Admiral Ushakov, the lead unit of four nuclear-powered 24,500 ton Kirov class battlecruisers completed by the Soviets between 1980 and 1996. Our four Iowa class battleships were taken out of mothballs, modernized, and recommissioned between 1982 and 1988 in response to these behemoths.


Aerial oblique view of the New Jersey firing three of her 16 inch guns (one from each turret) simultaneously, after being recommissioned for an unprecedented fourth time in December 1982. Every Naval officer wanted to get a closer look at the old battleships. I was fortunate to have actually gotten aboard the Missouri for a short stint.


The business end of the Iowa firing three of her 16-inch rifles at targets in a firepower demonstration for visiting dignitaries from Guatemala in August 1984. As I recall, the Iowa had been dispatched to Guatemala to render medical and dental assistance. Simultaneous firings did so much vibration damage to the computers aboard ship, they began firing one rifle at a time, with some interval between.


This view shows the New Jersey firing a Tomahawk cruise missile. The Iowa class battleships were reconfigured to carry 32 Tomahawk and 16 Harpoon missiles, as well as four Phalanx CWIS gatling guns. Three of four were decommissioned in the fall of 1991, following the first Gulf War. The Missouri was retained for a few more months with a reduced crew so she could attend the 50th anniversary of the Pearl Harbor attack ceremonies in December 1991. The Missouri had hosted the Japanese surrender in Sagami Bay near Tokyo on September 2, 1945.


I am the officer in the leather flight jacket on the bridge of the USS Missouri while the crew mans the rails as we depart San Francisco Bay following the ship’s first port call in July 1987. The Missouri's coning tower armor was 17 inches thick, making it pleasantly cool inside during most days at sea. The belt armor protecting the hull was over 12 inches thick and inclined at 19 degrees from vertical, to protect the ships from armor piercing shells.


Propulsion on an Iowa Class battleship, as revealed in drydock. The five-bladed inboard screws were 17 feet in diameter while the 4 bladed wing screws were 18’-3” in diameter. The design power output was 212,000 shaft horsepower (shp), with a 20% overload (up to 254,000 shp). During the New Jersey’s sea trials in December 1943 the engine room generated 221,000 shp, clocking 31.9 kts with a displacement of 56,928 tons. The Iowas were the fastest battleships ever built, by a wide margin. Their design speed was about 33.5 kts (38 mph), but a lightly loaded hull (51,000 tons) would have been capable of achieving 35.4 kts (40.25 mph). That's fast enough for waterskiing!


The Need for Speed. My sketch depicting the equations used to determine the optimal waterline length for maximum speed, presenting examples for 12 meter racing yachts (used in the America Cup races) and World War II era destroyers and cruisers/battleships. These values were empirically derived from model hull studies at the David Taylor Ship Basin in Cabin John, MD in the 1930s and 40s. The length-to-beam ratio for the Iowa Class battleships was 7.96.


In the post World War II-era naval architects established a hydrodynamic order or merit that eliminated the effect of displacement. The most common comparison was this graph comparing the "power coefficient" (shaft horsepower divided by the displacement and multiplied by the speed) against the speed divided by the square root of length ratio. Measured data for Iowa Class battleship sea trials plotted very close to the line shown for cruisers.


The width of the Iowa Class battleships was limited by the dimensions of the Panama Canal locks. The maximum beam that could transit the Canal was 108-1/6 feet because the locks are 110 feet wide. This beam dimension was then multiplied by 7.96 to determine the waterline length of 860 feet. This shows the battleship Iowa transiting the Pedro Miguel Locks on June 6, 1984. Looks like a tight fit!


The Iowa Class battleships were designed to be immune from 18-inch armor piercing naval gunfire at ranges between 18,000 and 30,000 yards. Below 18,000 yards the lower trajectories of incoming shells could conceivably pierce the inclined hull armor package.