The battleship USS Mississippi was a veteran of both world wars but is perhaps more important for technological contributions to modern naval warfare after WWII.
(USS Mississippi during WWI as built, during WWII after a complete rebuild, and during the Cold War as a missile test ship.)
As built, USS Mississippi (BB-41) was the second of three New Mexico class battleships. USS Mississippi was launched at Newport News on 25 January 1917 and commissioned on 18 December 1918. As built, USS Mississippi displaced 32,500 tons and measured 624’x97’5″x30′.
The original design was typical of the WWI era. The battleship was armed with twelve Mk11 14″ guns in four heavily-armored triple turrets. These guns fired 1,500 lbs shells out to 20 ½ NM. The secondary armament was fourteen Mk7 5″ guns on deck and eight more in casemate mounts. These guns had a range of 9 NM. Finally, there were two 21″ torpedo tubes which were basically useless and soon plated over.
USS Mississippi was heavily armored, with a 13 ½” belt, 3 ½” deck, 9″-18″ on the turrets, and 11 ½” on the superstructure. The battleship was powered by four geared steam turbines turning four shafts, and had a top speed of 21 kts. The original crew was 55 officers and 1,026 enlisted. USS Mississippi had the “wastepaper baskets” characteristic of American warship design of the time; these hyperboloid lattice structures were topped with crew’s nests for spotters to visually range shell splashes in the pre-radar era.
Modernization and WWII
In 1931-1933, USS Mississippi was almost completely redesigned from the weather deck up. A completely new superstructure was added, and the wastepaper baskets were replaced by pole masts to support radars. The ship’s appearance radically changed. The armament was retained but the nearly-useless casemate mounts were plated over, and quadruple Mk1 1.1″ anti-aircraft guns were added. A seaplane catapult and handling crane was installed on the stern. The changes added about 1,000 tons to the displacement and knocked a half-knot off the top speed.
USS Mississippi was in the Atlantic Ocean when Pearl Harbor was attacked and thus was undamaged. Additional 20mm anti-aircraft guns were added and the battleship was sent to the Pacific, participating in some of the early battles there. In 1944, USS Mississippi underwent a refit at Puget Sound Naval Shipyard. Newer radars were installed, and the anti-aircraft fit was massively increased with 3″, 40mm, and 20mm guns replacing the 1.1″ weapons.
The following year, USS Mississippi had another refit, this time at Pearl Harbor, with twin Mk38 5″ turrets replacing the open WWI-era 5″ guns. These guns were without question the best dual-purpose naval weapons of WWII. The added weight knocked another half-knot off USS Mississippi‘s speed. This was the final configuration of USS Mississippi in the battleship role.
USS Mississippi‘s most famous engagement was in the Suriago Straits during the October 1944 Battle of Leyte Gulf. In a night duel, USS Mississippi and five other American battleships faced off against the Japanese battleships IJN Yamashiro and IJN Fuso, three cruisers, and nine destroyers. The American battleships used the age-of-sail “Crossing The T” maneuver (the last time it was used) and annihilated the Japanese flotilla. Using only radar, the American battleships pounded the Japanese force before they could turn to engage. The battle started at 03:53 local time, when USS West Virginia (BB-48) opened fire on the Japanese battleships, soon joined by the other battleships. USS Mississippi was the last ship in the battle line to open fire as her radars were masked by the rest of the battle line. At 04:06 local time, USS Mississippi fired one full broadside (all twelve 14″ guns) at IJN Yamashiro. Most or all of USS Mississippi‘s armor-piercing rounds hit; although it barely mattered as the Japanese battleship was literally being ripped apart by repeated heavy-caliber hits. A few seconds later, a cease-fire order was given as the American commander was concerned that the ranges were closing so fast that there was a friendly-fire danger. The obliterated wreck of IJN Yamashiro sank shortly thereafter.
(After WWII ended, the captain of USS Mississippi presented the 48-star flag flown during the Suriago Strait engagement to the state of Mississippi. In the lower photo, then-Governor Thomas Bailey is raising the flag at the Mississippi Statehouse.)
USS Mississippi after WWII
The US Navy had already decided to retire the whole New Mexico class at the conclusion of hostilities, whenever that might be. However when Japan surrendered, it was decided to retain USS Mississippi for conversion into a gunnery training vessel, to relieve the elderly USS Wyoming (AG-17), itself a converted ex-battleship. During the war, USS Wyoming had proven to be a great asset as new gunnery technology and tactics could be practiced on a sea-going ship, and gun crews being sent to the Pacific arrived already trained.
(USS Mississippi on the Mississippi River in October 1945. The vessel is still numbered as a battleship (BB-41) and is unaltered from the war which had ended two months previous. This was one of the last times a battleship was on the river.)
In November 1945, USS Mississippi arrived at Norfolk Naval Shipyard, VA, to begin the conversion from battleship to gunnery training ship. The conversion lasted until July 1947, at which time USS Mississippi was placed back in service, now classified as an “experimental auxiliary”, hull number EAG-128 (the “E” was later dropped).
(USS Mississippi (AG-128) in 1947, very shortly after the completion of the conversion in Norfolk. The “A”, “B”, and “X” Mk11 14″ main turrets have all been deleted. The aftermost “Y” turret was left aboard to maintain a stable center-of-gravity, but it was deactivated and carried no ammunition. The Mk38 twin 5″ turrets are still aboard on the starboard side, as seen here. All the 20mm guns are removed, as were most of the 3″ and 40mm guns. The prototype SX is on the aft pole mast. The catapult is still aboard however USS Mississippi’s Kingfisher planes had already been assigned elsewhere.)
One of the first systems tested was the radar designated SX, which had originated late in WWII as the US Navy’s project CXHR. This long-range, three-dimension air search radar was successful and was introduced to the fleet as AN/SPS-8, which was installed on WWII-veteran aircraft carriers.
(USS Mississippi in 1948. Barrels of the single Mk30 turrets can be seen protruding from the port side, while the starbord side still has the Mk38 twin guns. Unusually, the ship is still using the wartime low-visibility (small-sized) hull number.)
The Mk38 twin 5″ turrets on the port side were removed and replaced by Mk30 single 5″ turrets. This allowed the ship to train crews on both designs at the same time. It was no longer important to maintain symmetry of the gun fit as the ship would never see actual combat again anyways.
(Taken during a 1949 visit to New York City, this photo shows USS Mississippi’s radar fit at the time. On the aft mast is the SX radar. The platform on the stack holds a WWII-era SO radar. The platform on the stub mainmast holds the prototype SR-3 radar. Atop the conning tower is a manned Mk37 gunfire control station with a Mk25 radar dish. A second, “loose” training Mk25 dish is on the small balcony next to the forward Mk38 twin 5″ gun. Also note three WWII-era liferafts stacked on the empty barbette where the “B” 14″ gun turret had once been.)
(USS Mississippi at Norfolk, VA in 1950; before the SAM modifications. The catapult had already been removed by this time however the seaplane crane was still onboard as it was useful for other tasks.)
The Mk16 6″ gun
USS Mississippi served as the trials ship for this twin cruiser gun, which was installed on the Worcester class cruisers; the US Navy’s first post-WWII cruiser class and final gun cruiser design. The twin Mk16 was intended to be equally effective against ships and aircraft, and to give light cruisers an AA weapon with longer range than the 5″ guns on destroyers.
The complete turret weighed 209 tons. The Mk16 6″ gun had a range of 11 ½ NM and a rate of fire of 12rpm. Operations aboard USS Mississippi went well, however, in fleet service the design had a number of problems related to jamming and oil leaks. It was not liked by it’s crews and was out of frontline service by 1959.
Project Bumblebee and USS Mississippi
The US Navy had originated “Project Bumblebee” during WWII, after the Luftwaffe began using the world’s first primitive air-to-surface anti-ship missiles. The objective was to design some sort of weapon and/or tactics to shoot down the German planes before they could launch and target the guided weapons.
The project took on great urgency after the Japanese kamikaze attacks started. Traditional anti-aircraft gunnery was no longer effective as there was only a brief window between the kamikaze coming into gun range and impacting the ship. Additionally, it was no longer enough to seriously damage the targeted plane, now it needed to be completely blown out of the sky before it reached the fleet. It was determined that a guided missile would be the best method of defending against kamikazes outside of gun range.
The initial operational date was scheduled to be early 1946, when the invasion of Japan was scheduled. Of course WWII ended in 1945 and in any case, designing the world’s first shipboard surface-to-air missile (SAM) was much more difficult than imagined and the main research efforts did not even begin until July 1946.
The project goals were split into long-range and medium-range missiles, of which (initially) it was thought that the long-range would enter service first. A developmental test rocket, called CTV-N-8, was built by the Applied Physics Lab of John Hopkins University. It was so successful that the US Navy decided that it would itself become the medium-range weapon, and that it would have priority over the longer-ranged missile.
USS Mississippi was selected as the test ship for the world’s first naval SAM, which had by now been named Terrier. In 1952 the ship underwent another modification for the role. The remaining 14″ turret, long since deactivated, was removed along with the WWII seaplane crane and the whole aft deck was rebuilt to hold two twin Mk10 launchers and Terrier magazines below deck. Additional electronics were installed to operate the missiles, as were a pair of pierside reloading cranes.
The missile magazines were accompanied by below-decks diagnostic shops to test and maintain the Terrier missiles. Early in the program, this was uncharted technological territory and each one had to be “pre-flighted” like a jet fighter.
(The starboard door of the upper mount on USS Mississippi opens to reload the launcher. The earliest versions of the Terrier missile loaded the missiles horizontally as shown. This required the launcher to come to 360° bearing and 0° elevation after each shot. Later, an inclined system was developed. Even more into the future, the US Navy switched to vertical loading for later SAMs.)
The first shipboard test-firing of RIM-2 Terrier was on 28 January 1953, with more the following day. The Terrier was 27’1″ long and was a two-part missile. The rear portion was simply a solid-fuel rocket which boosted the missile off the launcher and accelerated it.
(USS Mississippi firing a Terrier during a mid-1950s exercise in the Atlantic Ocean.)
After several seconds, the booster exhausted and dropped away, at which time the “front end” part of the missile ignited and carried the weapon to the target aircraft.
(A small camera mounted to the rear booster captures the exact instant when the exhausted first stage separated, before the front end of the missile ignited. The bracket on the falling booster locked into a rail on the shipboard launcher holding the Terrier in place after loading.)
The earliest version of the Terrier, as carried by USS Mississippi, used the beam-riding technique. An aircraft detected by other means was passed to the firing team. A radar then cast two (inner and outer) corkscrew-like “beams” of radar waves, one of which captured the inflight missile and the other the target. This was then calculated into a trajectory. USS Mississippi then radioed commands to the missile to adjust it’s flight so that the two would meet up. The Terrier’s 218 lb HE-Frag warhead was then detonated by radio command at the precise best moment, showering the target plane with shrapnel and destroying it. Of course, if the missile happened to physically strike the plane, the impact alone would destroy it.
(USS Mississippi fires a Terrier in 1954. The beam-riding radar is the one which looks like a searchlight being held up by two arms. This radar on USS Mississippi was a jury-rigged X-band system which used bits and pieces of other existing radars. The production model for fleet use was the C-band AN/SPQ-5, which was later replaced by AN/SPG-55 after the beam-riding concept was abandoned.)
As might be expected with a technology leap this big, there were problems with Terrier. Most of them were related to the beam-riding concept. The dish had to be pointed at the target at all times. If the plane was at low altitude, the radar beam sometimes locked onto the surface of the ocean and crashed the missile. After USS Mississippi had left service, the US Navy abandoned the beam-rider concept and switched to semi-active radar homing, which it continues to use to the present day.
(The targets for USS Mississippi’s SAM tests were usually WWII-surplus F6F Hellcat fighters, converted into radio-controlled drones. These were often controlled by nearby F8F Bearcat fighters, another WWII design. In the above photo, the missile command-detonates near the Hellcat, showering it with hot shrapnel.)
Project Bumblebee was a tremendous success, and was a revolution in naval weaponry similar to the introduction of guns and radio. Besides the medium-range RIM-2 Terrier, the project yielded the long-range RIM-8 Talos, and a third SAM, the short-range RIM-24 Tartar, which was basically the front end of a Terrier without the booster. Together, the “Three T’s” were the backbone of shipboard anti-aircraft defenses for the US Navy and other NATO navies during the first part of the Cold War. Later shipboard SAMs (including the RIM-174 Standard currently in use in 2015) directly descended from Project Bumblebee, so USS Mississippi‘s contribution was important.
(USS Mississippi (AG-128) in the mid-1950s, inport after a missile test. This photo shows the single-barrel 5″ turrets on the port side and the twin mounts to starboard, with the twin Mk16 turret in the old “A” position.)
The Petrel project and final years
The last ordnance project that USS Mississippi was involved with was the AQM-41 Petrel missile. This dated back to the WWII Project Kingfisher, which sought a way for warplanes to drop torpedoes outside the range of AA guns. The Petrel was simply a Mk21 torpedo attached to a wooden fuselage with a J44 jet engine inside.
The Petrel was supposed to be fired from a launch plane (the P-2 Neptune is the only one which ever carried it) about 17 to 18 nautical miles from the target, flying at 200′ altitude. When it had closed to 4,500′ range, it broke apart and the torpedo dropped into the water to finish the attack.
The Petrel had a number of problems. To begin with, it was overall unreliable. It was discovered that it could only be used against surface ships or submarines on the surface. By the 1950s, most submarines patrolled non-stop underwater and against a surface ship, Petrel was a complicated and expensive way of mounting an attack. In flight, it was slow and could be shot down with WWII-era guns. The weapon never entered frontline use and the US Navy eventually expended them as AA target drones.
The Petrel project concluded at the end of February 1956. By then, USS Mississippi was no longer attractive as a trials ship. The vessel was very fuel-thirsty as it had to lug around the weight of it’s armor from the battleship years. The boilers were wearing out and the ship could no longer even make 20 kts. The test ship USS Norton Sound (AVM-1) relieved USS Mississippi in the weapons development role.
On 30 July 1956, USS Mississippi finished her last training mission and began deactivation. The US Navy formally decommissioned the old former battleship on 17 September 1956. There was no desire to retain the vessel in reserve and the ship was immediately put up for scrap sale. The Bethlehem Steel Company purchased it on 28 November 1956. On 7 December 1956, the 15th anniversary of the Pearl Harbor attack, tugboats retrieved the ship and towed it to Baltimore, MD where it was broken apart in 1957.
Some of the ship’s wardroom silverware was inherited by the next USS Mississippi (CGN-40) in 1978, and then again by USS Mississippi (SSN-782) in 2012. The ship’s bell is preserved at Rosalie Mansion in Mississippi.