The battle of the Sibuyan Sea (23-24 October 1944) was the opening phase of the battle of Leyte Gulf and saw American submarines and carrier aircraft attack Admiral Kurita's I Striking Force, sinking the massive battleship Musashi.
The Japanese plan at Leyte Gulf involved four fleets which were to attack from three directions. Admiral Ozawa's carriers were to attack from the north and try and draw the main American fleets away from the landings at Leyte Gulf. Admiral Kurita had overall command of the forces attacking from the west. Their role was to break into Leyte Gulf from the west and try and devastate the American shipping found there. Kurita split his force into two. He led the larger part, which was to pass through the Philippines, emerge from the San Bernardino Strait and attack Leyte Gulf from the north. The smaller part of his force was to attack Leyte Gulf from the south, supported by the fourth and smallest of the fleets.
Kurita commanded one of the most powerful battleship forces of the Second World War. He may have only had five battleships but amongst them were the Musashi and Yamato, the largest and most powerful battleships of the war, each armed with nine 18.1in guns. He also had the Kongo and Haruna, two pre First World War battle cruisers that had been turned into battleships in the late 1920s partly by doubling the amount of armour they carried. Finally he had the Nagato, a 16in battleship launched in 1919. He also had twelve cruisers, including his flagship III and fifteen destroyers.
Kurita's fleet was based at Lingga, south of Singapore, where it was close to its sources of fuel. From there it sailed east, reaching Brunei (Borneo) on 20 October. Early on 22 October Kurita sailed from Borneo. His route would take him to the north of the long narrow island of Palawan. He would then sail south of Mindoro into the Sibuyan Sea in the centre of the Philippines. He would then sail east, with Luzon to his north, eventually passing through the San Bernardino Strait, which separated Luzon and Samar. Finally he was to turn south, sail down the coast of Samar and reach Leyte Gulf from the north.
Things began to go wrong well before Kurita reached the Sibuyan Sea. Two American submarines, Dace and Darter, were patrolling the waters to the north of Palawan. Just after midnight on 23 October the Japanese fleet was detected by Darter's radar. The two submarines moved to intercept the incoming fleet. By 5am they were in position to attack.
Their attack was devastating. Kurita's flagship, the cruiser Atago, was hit and sank so quickly that the admiral had to swim for safety. A second cruiser, the Maya, was also sunk, and a third, the Takao, had to turn back to Borneo. Two destroyers returned with her to act as a screen.
Despite these losses I Striking Force was still a very powerful force, but worse was to come. The fleet entered the Sibuyan Sea early on 24 October, where at around 8am it was detected by an American search plane. Halsey took direct command and ordered three of his carrier task forces to attack the incoming Japanese fleet. Aware that he was likely to be attacked Kurita requested air support from the Philippines, but most Japanese aircraft remaining on the Philippines were engaged in the battle around Leyte. On 24 October both the naval and army air services launched attacks on the American fleets. The navy aircraft sank the carrier Princeton but at heavy cost, and Kurita was left unprotected.
The American attacks began in mid-morning. Musashi appears to have been their main target. She was hit by a bomb and a torpedo in the first attack, three torpedoes in a second attack at around noon and four bombs and a torpedo in a third attack at around 1.30. This third attack finally did some serious damage. Her speed dropped and she began to fall behind. Kurita slowed the rest of the fleet to allow the Musashi to keep pace.
The fourth attack began to threaten the survival of the ship. Three torpedoes hit, as did several bombs. The first hit the main bridge killing everyone there, but not the captain, who by chance had moved to a higher observation position. More bombs quickly followed. This time her speed was reduced to 15kts and she was listing to port. Electrical power was out.
The fifth attack left Musashi only capable of 6kts. Kurita ordered her to turn back and try and reach Borneo. At the same time another cruiser was forced to turn back. Kurita still had four battleships and eight cruisers, and he was approaching the western end of the San Bernardino Strait. He was now seriously worried about the danger to his fleet if he entered the strait in daylight and so at 4pm he ordered his fleet to turn back to the west to try and get out of range of American aircraft. About an hour and a half later he felt safe enough to turn back east and begin the passage of the straits. The next morning he would emerge from the straits, surprise the Americans and nearly win a significant victory (battle of Samar, 25 October 1944).
In the meantime the Musashi was slowly plodding west with an escort of two destroyers. Despite the very heavy damage she had suffered the giant battleship didn't sink until after 7pm, after a long struggle to correct her list to port had failed.