Shinano: The World’s Largest Warship Sunk in 17 Hours (WW2)

Added: 2026-05-06

[00:00:00]On the 29th of November 1944, the largest warship ever built sank to the bottom of the Pacific Ocean. She had been at sea for exactly 17 hours, six torpedoes, one American submarine, 2,515 men lost. The most expensive, most powerful naval construction project in Japanese history gone before she fired a single shot in anger.

[00:00:26]This is how it happened.

[00:00:29]Shinano had started life as the third Yamato-class battleship.

[00:00:34]She was the largest ship ever constructed at 870 ft in length and 72,000 tons.

[00:00:41]She also had many gun emplacements in a mostly anti-aircraft role, but could be used against surface ships also. She also had advanced for its time command and control [music] and radar. In June 1942, four Japanese fleet carriers were destroyed in a single afternoon. The decision was made almost immediately.

[00:01:01]The third Yamato hull would become a carrier, not a strike carrier, a support ship.

[00:01:08]The same class as Yamato and Musashi, the largest, most heavily armed battleships ever constructed. On the 28th of November 1944, she left Yokosuka naval base on her delivery voyage south to Kure escorted by three destroyers. She was not ready.

[00:01:25]There were civilian workers still completing fitting out tasks below decks. Her captain, Rear Admiral Toshio Abe, knew all of this. He pressed on regardless. The orders were clear and the need was urgent. Shinano would make the voyage and complete her fitting out at Kure. It was a decision that would cost 2,515 men their lives.

[00:01:48]USS Archerfish was a Balao-class fleet submarine on lifeguard patrol off the Japanese coast. Stationed to recover American airmen who ditched in the sea after raids on Japanese targets.

[00:02:03]On the evening of November 28th, Archerfish's radar picked up a massive contact at 20 mi bearing northeast. The contact was enormous.

[00:02:13]It was making 20 knots on a southwest heading. And it was escorted by multiple smaller contacts, destroyers screening in formation.

[00:02:24]The legendary chase between the United States submarine and the Japanese super carrier was about to begin.

[00:02:32]Shinano was faster on the surface than Archerfish was submerged. If he dived to attack, he would lose the contact entirely in boat. The target would simply drive away from him.

[00:02:43]He had one option, chase her on the surface. He rang up full speed on the diesels and began the pursuit.

[00:02:50]For 6 hours, Enright chased. Then, Shinano's captain made the decision that sealed his ship's fate.

[00:02:58]Admiral Abe ordered zigzagging.

[00:03:01]It was the correct anti-submarine procedure. A ship that maintains a predictable course is easy to intercept, and Abe's lookouts had almost certainly detected Archerfish's radar transmissions. The zigzag was tactically sound, but every course change reduced Shinano's effective speed over the ground. Every turn shortened the distance between hunter and hunted.

[00:03:23]Enright watched the pattern. He plotted each leg. He calculated the interval, the turn angle, the next heading. The next leg would bring her directly across Archerfish's bow at firing range. He gave the order to dive. He set his firing solution. He waited. The Archerfish held position and speed, and a Japanese destroyer passed almost directly overhead. The Archerfish's crew held their breaths and did not move a muscle.

[00:03:50]The destroyer passed over without dropping depth charges.

[00:03:54]At 0300 on November 29th, Shinano's zigzag brought her across Archerfish's bow at 1,400 yd.

[00:04:04]Enright had his window. He fired six Mark 14 torpedoes in a spread and immediately began his escape.

[00:04:12]Four hit. The first at 0317.

[00:04:17]Three more in rapid succession, each 292 kg torpex warhead punching through Shinano's hull below the armored waterline belt. Flooding began in multiple compartments simultaneously.

[00:04:29]The three escorting destroyers immediately turned toward Archerfish's last known position and began dropping depth charges.

[00:04:37]Enright drove Archerfish deep and ran.

[00:04:41]And far above her in the dark Pacific waters, Shinano sailed on.

[00:04:47]Admiral Abe was told by his damage control [music] teams that the flooding was serious but manageable.

[00:04:53]The pumps could handle it. The ship could make Kure.

[00:04:57]Abe believed them. He maintained speed and continued south. It was the last fatal decision of the voyage. Four torpedo hits should not have sunk Shinano. A properly prepared ship of Shinano's size, displacement, and armor protection should have survived four torpedo hits and made port with damage.

[00:05:18]The designers had accounted for far worse, but Shinano was not properly prepared. Her watertight integrity system was unfinished.

[00:05:27]When the water entered through the four torpedo holes, it did not stay in the damaged sections. It moved through unsealed pipes, through improperly fitted doors, through gaps that a finished ship would not have had. By dawn, Shinano was visibly settling.

[00:05:45]At 10:57 on November 29th, 1944, 7 hours and 40 minutes after the first torpedo struck, Shinano capsized and sank in 1,400 m of Pacific water.

[00:06:00]2,515 men went down with her.