THE SHOKAKU DESTRUCTION 1944: 1,272 Japanese Dead INSIDE Her

[00:00:03]At 11:18 in the morning of June 19th, 1944, Commander Herman J. Kosler of the American submarine USS Cavala fired six torpedoes at the Japanese aircraft carrier Shukaku from a range of approximately 1,200 yd. Three of them struck the carrier's starboard side at 11:22 as she was recovering and refueling the aircraft returning from her strike against the American fleet.

[00:00:28]The aviation fuel in the refueling lines ignited. The fires spread through the hangar deck. 1,272 of the Shokaku's crew of approximately 2,000 were dead before the ship sank at approximately 1,400 hours that afternoon. The Shokaku had been at Pearl Harbor when the Pacific War began. She had launched the aircraft that attacked battleship Row on December 7th, 1941.

[00:00:54]She was sunk 2 years, 6 months, and 12 days later while recovering the aircraft of a battle Japan had already lost.

[00:01:01]1,272 dead, 2,000 crew, three torpedoes, 2 hours and 38 minutes from the first hit to the bottom. The carrier that launched aircraft at Pearl Harbor was sunk while recovering aircraft from the battle that ended Japanese carrier aviation. If this story matters to you, subscribe to the channel. Just subscribe, that is all.

[00:01:23]Thank you. The Shukaku was commissioned into the Imperial Japanese Navy on August 8th, 1941, 4 months before Pearl Harbor. She was the lead ship of her class and among the most capable fleet carriers Japan had built to that point in its naval construction program. Her full load displacement was 25,675 tons. Her flight deck extended 242 m in length. She was designed to operate approximately 72 combat aircraft in normal operations. She was powered by eight campon boilers driving four sets of turbines producing 160,000 shaft horsepower, giving her a maximum speed of approximately 34 knots. She was faster than any American fleet carrier then in commission when the Pacific War began in December of 1941. When she departed Hitokapu Bay at Torfu Island on November 26th, 1941, she was one of the six carriers of the Kido Bhai, the strike force that Vice Admiral Chuichi Nagumo commanded against Pearl Harbor. The six carriers of the Kido Bhutai were the Akagi, Kaga, Soryu, Hiryu, Zuikaku, and the Shokaku.

[00:02:39]Together they carried approximately 430 combat aircraft for the Pearl Harbor operation. The attack on Pearl Harbor on December 7th, 1941 was the direct product of that combined carrier air power. The Shukaku was among the newest and alongside her sister ship, the Zuikaku, among the most capable of the six. Her aircraft participated in both the first and second waves of the Pearl Harbor attack. She launched torpedo bombers that attacked the battleships morowed in Pearl Harbor and dive bombers that attacked parked aircraft on the ground at the American airfields. She departed from the waters north of Oahu on December 8th as part of the returning fleet and sailed back toward Japan with the rest of the Kido Bhai. She had been one of the carriers central to the attack that sank or disabled eight American battleships and killed 2,43 American servicemen. By June of 1944, four of the original six Pearl Harbor carriers had been sunk. The Akagi, Kaga, Soryu, and Hiryu had all been sunk at the Battle of Midway in June of 1942.

[00:03:47]The Shukaku had not participated in Midway. She had been at the Battle of Coral Sea in May of 1942, where she had been badly damaged by American dive bombers and was forced to withdraw before the battle's conclusion. Because she was undergoing repairs from the Coral Sea damage, she was not available for the Midway operation. The four carriers that did go to Midway died there. The Shukaku survived because she had been too damaged at Coral Sea to be ready for Midway in time. The Shukaku's record between Coral Sea and June of 1944 included three significant engagements. At the Battle of the Eastern Solomons in August of 1942, her aircraft helped score hits on the American fleet carrier USS Enterprise, forcing her out of action for repairs.

[00:04:33]At the Battle of Santa Cruz Islands in October of 1942, her aircraft helped sink the American fleet carrier USS Hornet. The Shaku was again damaged by American dive bombs and forced to withdraw. The Hornet sinking was the most significant Japanese carrier aviation achievement of the late 1942 campaign. Through most of 1943, she was kept in reserve, waiting for the anticipated decisive fleet engagement the Japanese command expected would eventually come. By the spring of 1944, she was the most combat experienced carrier remaining in the Japanese fleet.

[00:05:11]Operation Ago was Vice Admiral Jizaburo Azawa's operational plan for the decisive battle that Japanese strategic naval doctrine had always anticipated.

[00:05:21]The American invasion of Saipan beginning June 15th of 1944 triggered its execution. Ozawa's mobile fleet would sorty from its anchorage at Tawittowi in the Philippines and engage the American fleet supporting the Saipan landings in a carrier battle designed to destroy American naval power in the central Pacific. The plan called for Azawa's aircraft to attack from distances beyond the range of American carrier aircraft, exploiting the longer combat radius of Japanese carrier planes and the favorable situation that Ozawa believed land-based aircraft operating from the Marana's airfields would create. The plan was internally coherent. The premises on which it rested had already been eliminated. By June of 1944, Japanese carrier air groupoups had been rebuilt numerically after Midway, but with replacement pilots who had not had the training time that had been available to the experienced men who died at Midway, Coral Sea, and Santa Cruz. American anti-aircraft improvements, including the top secret proximity fuse that detonated shells when they came near aircraft rather than requiring a direct hit, had fundamentally changed the tactical balance over carrier task forces. The Grumman F6F Hellcat had replaced older American carrier fighters and consistently outperformed the Mitsubishi Zero in most combat situations. The Japanese command understood some of these disadvantages and expected to offset them through the range advantage of their aircraft and through land-based aircraft operating from the Marana's Island airfields. When Azawa's aircraft launched their strikes on June 19th, the land-based aircraft on the Marana's airfields had already been substantially destroyed by American carrier strikes conducted in the preceding days. Hosawa launched four separate strike waves against Task Force 58 on the morning of June 19th. The waves were intercepted by American fighters well before most of them reached the American fleet. American anti-aircraft fire and fighter interception destroyed the Japanese aircraft at a rate that the American pilots who flew those interception missions described informally as a turkey shoot. Of the approximately 350 carrier aircraft that Ozawa launched in the morning strikes, fewer than 130 returned to the carriers. The aircraft that did return were the survivors of an operational catastrophe that had been decided before they landed.

[00:07:49]They were among the planes that were landing on and being struck below the Shukaku when Kler's torpedoes arrived.

[00:07:55]Commander Herman J. Kler was on his first war patrol in command of the USS Cavala, a Gateau class submarine, when he found the Japanese mobile fleet on June 17th. He tracked the fleet for several hours and made the decision to report its position rather than attack immediately. The intelligence he transmitted, providing the position, course, and speed of the Japanese fleet, contributed directly to the American tactical decisions that shaped the battle of the Philippine Sea. After transmitting the intelligence report, he received orders to proceed to his assigned patrol area. 2 days later, on June 19th, the Cavala encountered the Shokaku recovering her aircraft. Kler identified the Shukaku through his periscope at approximately 11 in the morning with her flight deck busy recovering aircraft from the returning strike waves. The carrier's flight deck was active with aircraft landing continuously and being struck below to the hanger for refueling and rearming before the next operation. The carrier was the largest target Kostler had ever observed through a periscope. He maneuvered the Cavala to within 12,200 yds of the Shokaku's starboard beam and ordered firing at 11:18 a.m. He fired all six torpedoes from the Cavala's forward tubes at 8second intervals. He began diving the Cavala deeper immediately after the last torpedo left the tube. Three of the six torpedoes struck the carrier starboard hull between 1120 and 1122.

[00:09:28]Costler did not know which specific ship he had struck until after he surfaced hours later and his crew could make a fuller assessment. The three torpedo hits on the Shukaku struck a carrier that was in the most operationally vulnerable position a carrier can occupy. She was actively refueling aircraft with aviation fuel flowing through the transfer lines into the tanks aboard the returned aircraft. One torpedo struck the starboard hull near the forward aviation fuel tanks and the forward bomb magazine. The explosion that followed this first hit was not simply the detonation of a standard torpedo warhead. It ignited the aviation fuel in the nearby tanks and in the transfer lines. The fire moved through the refueling transfer lines, through the connected fuel tanks, and across the hanger deck where aircraft were loaded with ordinance that had not been safely secured before the attack. The ordinance that had not been safely secured detonated. The aircraft themselves burned with their remaining fuel. The hanger deck became a continuous source of secondary explosions from ordinance and aircraft fuel that the crew could not control with the available firefighting capacity. Japanese fleet carriers of the pre-war design, including the Shokaku, had aviation fuel tanks constructed as integral structural components of the ship's hull. British fleet carriers of the same period stored aviation fuel in separate isolated tanks, insulated from the main structure by surrounding seawater. The Japanese design made the aviation fuel a loadbearing structural element of the ship's internal structure. After the catastrophic losses at Midway, the spaces around the Shukaku's aviation fuel tanks had been filled with concrete rather than the inert gas that had previously been used for fire protection. The concrete reinforcement did not prevent volatile aviation fuel vapors from spreading through the ship when the fuel tanks were damaged or compromised. Under normal peacetime operating conditions, the tanks were sealed and the vapors were contained within the sealed compartments. Under active combat operational conditions with fuel flowing through open transfer lines to aircraft waiting on the hanger deck, that seal was effectively broken before the torpedoes arrived. The Shukaku took approximately 2 hours and 38 minutes to sink from the time of the first torpedo impact. The damage control crew fought the fires continuously for the entire period. They could not suppress them. The bow went under first as water flooded through the damaged forward aircraft elevator shaft into the hanger below. Sailors on the flight deck slid uncontrollably down the tilting surface as the bow dropped into the sea.

[00:12:14]The open elevator shafts were burning from the fires below the flight deck.

[00:12:18]The sailors who slid into those open elevator shafts died in the fires below.

[00:12:23]The Shukaku went completely under at approximately 1,400 hours on June 19th, 1944.

[00:12:31]570 survivors were eventually pulled from the oil covered water by the Japanese destroyers that had been escorting the carrier. 1272 of her crew were not recovered by any rescue operation. The Japanese destroyers that conducted the rescue operation did so under the threat from American submarines that were still operating in those waters.

[00:12:52]The depth charge attack they had initiated against the Cavala immediately following the torpedo strikes had failed to locate the submarine. The Cavala had dived to depths that placed her below the effective detonation range of most of the Japanese depth charges. 106 depth charges in total were dropped in the 3 hours following Costa's attack. The Cavala sustained minor damage but remained fully operational. Costler brought the Cavala to the surface when the area was clear of Japanese destroyers, assessed the damage, and continued his first war patrol to its scheduled conclusion. The specific vulnerability of the Shokaku during Kosler's attack in June of 1944 had a direct parallel in every major Japanese carrier loss of the Pacific War. The Akagi, Kaga, Soryu, and Hiryu at Midway had all been caught in the process of rearming aircraft with bomb-loadaded planes on the hanger deck and aviation fuel in the transfer lines. Those four carriers at Midway sank within hours of the American dive bomber attacks for the same fundamental reason the Shukaku sank in the Philippine Sea. The ordinance and aviation fuel aboard the aircraft on the hangar deck multiplied the destructive effect of the initial hits. The Shokaku had survived Coral Sea partly because the bomb hits she sustained were on the flight deck rather than penetrating into the hangar and the hanger was not in active refueling status when she was struck. She survived the Santa Cruz engagement for similar structural reasons at the Philippine Sea on June 19th of 1944. She was in the worst possible operational condition when Costa found her through his periscope.

[00:14:34]The full scale of the Japanese air losses on June 19th was not known to Azawa as the battle was occurring. The mobile fleet was operating under radio silence and beyond visual observation range of the carrier air battles happening above the American fleet. His aircraft launched their four strike waves and the operational information that returned with the survivors was fragmentaryary. When the surviving aircraft came back to the carriers, they brought the news of the disaster with them in the simplest possible way. Not all of the aircraft that had launched returned. Not even most of them returned. Of those 350 aircraft launched in the morning strikes. Approximately 220 did not come back to the carriers.

[00:15:18]The carrier air groupoups that had been rebuilt over 2 years after Midway at great cost and positioned for this decisive engagement had been essentially destroyed in less than a single day of fighting. Ozawa did not have another set of air groupoups to rebuild from. The Cavala's decision to report the Japanese fleet position on June 17th before attacking was one of the more consequential individual command decisions of the Pacific War submarine campaign in the central Pacific. Costler had two options when he encountered the mobile fleet on June 17th. Attack immediately, which might have produced immediate results, or track and report, which would give the American fleet command the information they needed to plan for the larger engagement. Costler chose to report rather than attack. The position, course, and speed data he transmitted allowed Admiral Raymond Spruent and Vice Admiral Mark Mitchell to make tactical decisions with specific knowledge of where the Japanese fleet was and where it was heading. The intelligence Costler provided made the battle of the Philippine Sea more thoroughly one-sided than it would have been if the Japanese fleet's position had not been accurately transmitted before the battle began. The Cavala did not sink any ships when she found the mobile fleet on June 17th. The intelligence she transmitted on June 17th was worth more to the outcome of the battle than the ships she might have sunk with an immediate attack. The Shukaku's crew conducted damage control operations for 2 hours and 38 minutes in conditions that were progressively and irreversibly worsening. The fires on the hanger deck, fed by burning aircraft and aviation fuel that had not been secured when the torpedoes hit, could not be isolated from the rest of the ship. The flooding in the forward sections created an increasing list that complicated every damage control operation aboard.

[00:17:11]The ship was simultaneously flooding forward and burning in the hanger. Two separate and serious problems that required different damage control responses and that consumed the attention of the same crew. The available pump capacity was insufficient to keep pace with the rate of flooding.

[00:17:28]The available firefighting capacity was insufficient to suppress fires that were being fed by actively burning aviation fuel from the open transfer lines. Every damage control measure that might have worked under normal conditions was complicated by the simultaneous and mutually reinforcing presence of uncontrolled flooding and uncontrolled fire in a ship that could not stop either one.

[00:17:52]The 570 survivors pulled from the water after the Shukaku sank represented approximately 28% of her total crew of approximately 2,000. The others had died in the fires in the flooding compartments below deck in the secondary explosions or went under with the ship when she finally capsized.

[00:18:12]The water immediately around the Shukaku was covered in aviation fuel that had leaked from the damaged and ruptured fuel tanks. Some of the survivors were pulled from this fuel-covered water by rescue ships from the escorting destroyers. Those destroyers remained under threat of additional American submarine attack throughout the recovery. They could not safely stop in one location for extended recovery periods. They recovered the survivors they could locate and then moved. The survivors they were unable to locate or left behind were not recovered by any subsequent operation. The battle of the Philippine Sea continued on June 20th with an American carrier strike against the westward retreating Japanese fleet.

[00:18:53]The strike caught the remaining Japanese carriers at extreme range, approaching the absolute limit of the American aircraft's fuel capacity for a return flight. The American aircraft sank one additional Japanese carrier, the Hyo, and damaged several other ships in the retreating fleet. When they returned to the American fleet after dark with barely enough fuel remaining to attempt a landing, many crashed into the sea.

[00:19:19]Mitcher ordered the carrier fleet to turn on all its lights and illuminate the fleet to guide the returning aircraft home, accepting the risk of Japanese submarine attack to save his aviators. The night recovery produced additional aircraft losses from fuel exhaustion and accidents. The total American aircraft losses across the two-day battle, including the night recovery crashes, were approximately 130 aircraft. Japan lost well over 400 aircraft. Japan also lost two fleet carriers to submarines on June 19th and a 3rd to American carrier aircraft on June 20th. The pilots who flew the interception missions on June 19th, 1944 gave the aerial engagement over Task Force 58 a name that has remained in historical use for 80 years. They called it the Mariana's Turkey Shoot and the name has remained.

[00:20:13]The name captured the experience from the perspective of the American fighter pilots who intercepted the Japanese strike waves, targets that were numerous, relatively slow, and not effectively defended against the aircraft being used to intercept them.

[00:20:27]An American pilot flying a Grumman F6F Hellcat in June of 1944 had advantages that did not exist in December of 1941.

[00:20:37]He had a faster, heavier aircraft with more firepower. He had been trained for significantly longer. He had considerably more accumulated combat experience. He had coordination with the fleet air defense system that included proximity fuse anti-aircraft shells and radar directed fighter direction officers who could vector him onto the incoming Japanese formations before they reached the American fleet. The Japanese pilots had the disadvantage of significantly fewer training hours, earlier generation aircraft, and no equivalent fleet air defense system to protect their carriers while their air groupoups were away. The turkey shoot result was not a coincidence. It was the accumulated operational difference between the two sides across 3 years of a carrier war that one side had been winning. Hit subscribe right now because coming up is what happened to the Taiho on the same day as the Shokaku. Why the Battle of the Philippine Sea ended Japanese carrier aviation as an operational force. What the Shukaku's history from Pearl Harbor through four major engagements tells us about what she was before she sank and why the Cavala that sank her is sitting in a park in Galveastston, Texas today where anyone can walk through her. Do not go anywhere. The Taihaho was Ozawa's flagship and the most modern fleet carrier Japan possessed in June of 1944.

[00:22:00]And she was sunk on the same day as the Shokaku by a different American submarine. The USS Albakor struck the Taihaho at 8:10 in the morning of June 19th with a single torpedo. The Taiho was the newest Japanese carrier. She had been commissioned 3 months before the Battle of the Philippine Sea in March of 1944. She had armor plating on her flight deck, a design feature specifically intended to protect the carrier from bomb damage of the type that had destroyed the four carriers at midway. The single torpedo hit caused a structural crack in one of the aviation gasoline storage tanks below deck. The gasoline began leaking. What happened next aboard the Tahoe was the result of a decision by an inexperienced damage control officer. The leaking gasoline produced vapors that needed to be controlled and vented carefully. The damage control officer, not understanding the correct emergency procedure, opened all of the ship's ventilation systems to clear the vapors.

[00:22:59]This action distributed the vapors throughout the entire Tahoe rather than safely removing them. By mid-after afternoon, the concentration of aviation fuel vapors throughout the ship had reached an explosive concentration level. At 1532, the vapors detonated.

[00:23:17]The Taiho was destroyed from the inside in a series of explosions that observers on other ships described as a simultaneous eruption across the entire ship. She sank at 1628 hours on June 19th. Ozawa had been evacuated to a destroyer before the final catastrophic explosions. The Taiho had been in commission for 3 months. She had been the largest and most modern carrier Japan possessed. A single torpedo hit and one wrong damage control decision had destroyed the largest and most modern carrier Japan possessed. The combined loss of the Shokaku and the Taiho on June 19th left Japan with only the Zuikaku as a fully operational fleet carrier. The Zuiaku was the Shokaku's sister ship and the surviving half of the pair that had participated in Pearl Harbor, Coral Sea, Eastern Solomon's and Santa Cruz. She had survived every carrier engagement of the Pacific War to that point. By the end of June 19th, 1944, she was the only Japanese fleet carrier that remained. Japan had entered the Battle of the Philippine Sea with nine carriers of various sizes and types. It ended the first day with one fleet carrier and a substantially reduced number of light carriers. The American carrier force that Japan had engaged was fundamentally intact. The Zuikaku's final engagement came in October of 1944 at the Battle of Lady Gulf. She served as a decoy in Vice Admiral Ozawa's northern force, specifically designed to draw the American carrier fleet away from the invasion beaches at Lee. She had virtually no operational aircraft to launch. Her assigned role was to be found and attacked not to fight effectively. The American carrier aircraft found her and attacked on October 25th, 1944. She absorbed multiple bomb and torpedo hits and began to sink rapidly. As she was going under, her surviving crew assembled in ranks on the tilting flight deck and saluted the battle flag as it was lowered for the last time. The last of the original Pearl Harbor carriers was gone. The Shoku had already been gone since June 19th. Together, the two ships had carried the aircraft that attacked Pearl Harbor in 1941.

[00:25:35]Together, by October of 1944, they were both gone. The Cavala returned to Pearl Harbor after completing her first war patrol and submitted her formal report on the sinking. She had been awarded a presidential unit citation for the combined intelligence and combat results of the mission. Commander Kler received the individual Navy Cross. The Cavala went on to complete five more war patrols before the war ended. During her third patrol, she sank the Japanese super destroyer Shimutsuki. After the war, she was converted to a Hunter Killer submarine and updated with new sonar technology. She was decommissioned in 1969 and transferred to the Texas submarine Veterans of World War II. She is currently preserved at the Galveistston Naval Museum in Seawolf Park on Pelican Island, Galveastston, Texas, where she is open for self-guided tours. She is the only submarine in the American fleet to have sunk one of the carriers that had participated in the Pearl Harbor attack of December 1941.

[00:26:38]August 8th, 1941, Shokaku commissioned 4 months before Pearl Harbor. November 26th, 1941. Kided Bhutai departs Hitokapu Bay. Six carriers. December 7th, 1941. Pearl Harbor. Shukaku launches aircraft in both waves. May 8th, 1942. Coral Sea.

[00:27:01]Shukaku damaged by bombs. Withdraws.

[00:27:04]Mrs. Midway. June 4th to 7th, 1942.

[00:27:08]Midway. Akagi Kaga Syu. Hiu sunk.

[00:27:12]Shukaku not there. August 24th, 1942.

[00:27:17]Eastern Solomon's Shukaku aircraft damage USS Enterprise. October 26th, 1942, Santa Cruz. Shukaku aircraft helped sink USS Hornet. Shukaku damaged again. June 15th, 1944. American invasion of Saipan. Operation Ago triggered. June 17th, 1944. Cavala detects mobile fleet. transmits position, course, speed. June 19th, 8:10 a.m. USS Albaore hits Taiho with one torpedo. June 19th, 11:18 a.m. Cavala fires six torpedoes at Shokaku. Three hit. June 19th, morning strikes.

[00:27:58]Approximately 220 of 350 Japanese aircraft lost. June 19th, 1532.

[00:28:06]Taihaho's vapors detonate. She sinks at 1628. June 19th,400 hours, Shokaku sinks. 1272 dead. June 20th, American strike on retreating Japanese fleet. Hio sunk. October 25th, 1944, Zuikaku sunk at Lady Gulf. Last Pearl Harbor carrier.

[00:28:28]Four factors explain the destruction of the Shokaku. The structural vulnerability of Japanese carrier design to aviation fuel fires. Her operational condition when attacked. Costler's tactical execution and the battle context that allowed him to approach undetected. The first factor was structural vulnerability.

[00:28:48]Japanese pre-war fleet carriers, including the Shukaku, stored aviation fuel in tanks built integrally into the ship's structure. American and British carriers, used isolated fuel storage systems. The integral design was adequate when the fuel tanks were sealed and undamaged. It was catastrophically inadequate when the tanks were hit by torpedoes. While aviation fuel was actively moving through transfer lines during refueling operations, this design flaw had destroyed four Japanese carriers at Midway in the same pattern.

[00:29:18]The Shukaku had survived Coral Sea and Santa Cruz because the hits she took struck the flight deck rather than penetrating to the hanger and fuel system.

[00:29:28]In June of 1944, in refueling configuration during active operations, she was in the configuration that made the design floor lethal. The second factor was operational timing. The Shokaku was recovering and refueling aircraft when Kosler found her. She was not in a protected or defensive configuration. She was in the most operationally active and therefore most vulnerable configuration possible.

[00:29:54]Aircraft on the hanger deck, fuel in the transfer lines, ordinance being loaded.

[00:29:58]Ka carrier in this state cannot maneuver aggressively, cannot effectively use her own weapons, and has the maximum concentration of flammable material in the most exposed spaces of the ship.

[00:30:10]Kler's attack arrived at the worst possible moment for the Shukaku's survival. The third factor was Costler's tactical execution. His decision to report rather than attack on June 17th was sound judgment about where the greatest military value lay. His approach and attack on June 19th was technically competent. He maneuvered to,200 yards, which gave his torpedoes a high probability of hitting a target the size of the Shikaku. He fired the correct number of torpedoes for the engagement geometry, and he executed his escape dive correctly. He survived the subsequent depth charge attack by going deep enough to be below the effective detonation depth of most of the Japanese charges. The attack succeeded because it was well executed at the right moment against a target that was structurally vulnerable and operationally exposed.

[00:31:02]The fourth factor was the battle context. The Shokaku was sunk while the air crews who might have provided some notice of an approaching submarine were returning from a failed strike. And while the Japanese air defense systems were fully occupied with managing the disaster happening in the air above the fleet, there was no effective Japanese anti-ubmarine coverage of the carriers at the moment Costler approached. The destroyers that should have been screening against submarine attack were occupied with other tasks. The battle of the Philippine Sea created the conditions that allowed the cavaler to approach the Shokaku undetected. The paradox at the center of the sinking of the Shukaku is not subtle, but it is worth stating precisely. The Shukaku launched aircraft at Pearl Harbor in December of 1941 and participated in the attack that began the Pacific War for the United States. She survived four major engagements over 2 and a half years while every other carrier from the Pearl Harbor Strike Force was sunk. She was sunk on June 19th, 1944 while recovering the aircraft of the strike that Operation Ago had sent against the American fleet. That strike had failed.

[00:32:12]The aircraft recovering aboard the Shokaku were the survivors of the force that had been destroyed by the same accumulated American advantages in training, aircraft, and tactics that had been building since December of 1941.

[00:32:26]The aviation fuel being pumped into those aircraft when Kosler's torpedoes arrived was the fuel of the strike that was supposed to change the course of the war. The carrier that helped begin the Pacific War was sunk by the fuel of the battle that ended the carrier war at sea. The Shukaku did not sink because the Americans were lucky. She sank because the Americans had been winning the carrier war consistently for 2 years and had built the advantages that made June 19th, 1944 inevitable. The Cavala sits in Galveastston, Texas, where she has been since 1971.

[00:32:59]She is open to visitors. Herman Kler lived to the age of 91 and died in 2002.

[00:33:06]He had risen to Rear Admiral. He is the commander who made the decision on June 17th not to attack when he found the mobile fleet and who attacked on June 19th when he found the Shokaku in active refueling configuration. Both decisions were operationally correct given what Kosler knew at each moment. The Shokaku is on the floor of the Philippine Sea at approximately 11° 50 minutes north latitude, 137° 57 minutes east longitude north of Yap Island. She has been resting there since June 19th, 1944, 80 years ago.

[00:33:42]1,272 people who sailed on her are resting there with her now. Subscribe to this channel right now and turn on notifications because every week we bring you the stories. The naval history is reduced to a casualty number and a battle date without telling you that the Pearl Harbor carrier survived Coral Sea and Eastern Solomons and Santa Cruz for 2 and 1/2 years before being sunk by a submarine on its first war patrol. that the submarine that sank her first chose to report the Japanese fleet rather than attack, and that this decision proved worth more than any ship she could have sunk, that the Taihaho, the most modern carrier Japan possessed, was sunk that same day by one torpedo and one wrong damage control decision, or that the Zuikaku, the Shukaku's sister ship and the last surviving Pearl Harbor carrier, assembled her crew in ranks on her tilting flight deck to salute the flag as she went under at Lady Gulf 4 months later. Hit subscribe then like. So this reaches the people who should understand what 1,272 dead inside a Pearl Harbor carrier means about what 2 and 1/2 years of war produces when one side is winning it.

[00:34:54]Drop a comment below telling us where you are watching from. We will see you in the next one. The specific conditions that allowed Costa to approach the Shokaku undetected require explanation.

[00:35:06]The Shokaku was in the center of a carrier formation protected by an escort screen of destroyers whose job was to detect and intercept exactly the kind of attack Costler executed. The screen failed for the same reason the Japanese air defense system failed on June 19th.

[00:35:23]The Battle of the Philippine Sea placed every Japanese defensive resource under extreme pressure simultaneously.

[00:35:30]The destroyers were managing the aftermath of the air attacks, coordinating with the carriers, and dealing with the general operational confusion of a major fleet engagement.

[00:35:40]The specific sector of the screen that should have been between the Cavala and the Shukaku was not maintained with the attention it would have received under normal operating conditions. Kler passed through it undetected and reached his firing position at,200 yd. The prominence of the June 19th date in Pacific War history has consistently overshadowed what happened on June 20th.

[00:36:04]Ozawa, having lost two fleet carriers the previous day and most of his aircraft to American fighters, chose to retreat westward on June 20th. The American fleet under the constraint that Spruent did not want to expose the Saipan invasion beaches to a Japanese surface attack did not pursue aggressively. On the afternoon of June 20th, Miter launched an air strike against the retreating Japanese fleet at extreme range, approximately 440 km. The strike found the Japanese fleet, sank the light carrier Hio, damaged other ships, and lost many aircraft to fuel exhaustion on the return flight. The decision to launch the strike at that range and Mitch's subsequent decision to illuminate the fleet for the night recovery were the two most consequential command decisions of June 20th. Both were necessary. Both were costly. The Shukaku's survival through four major engagements before her sinking is worth examining as a specific historical fact.

[00:37:03]At Coral Sea, she was hit by three bombs and badly damaged but survived. In the Eastern Solomon's engagements, she participated without being seriously damaged. At Santa Cruz in October of 1942, she was again hit by bombs, again badly damaged, but again not sunk. She returned to Japan each time for repairs and refitting. She was a durable ship that had demonstrated the capacity to absorb significant battle damage and return. The difference between those three survivals and her sinking in June of 1944 was not the number of hits she took or the skill of her damage control crew. It was the state she was in when the hits arrived. Three bomb hits while the hanger was in normal operating condition produced survivable damage.

[00:37:52]Three torpedo hits while aviation fuel was flowing through open transfer lines produced fire that her crew could not control. The recognition that the Cavala received for her first war patrol eventually became one of the most significant sets of awards given to any American submarine crew of the war. The presidential unit citation was the highest unit decoration available and was awarded for the combined intelligence contribution of June 17th and the sinking of the Shukaku on June 19th. Kler's individual Navy cross recognized what the citation described as exceptional heroism and outstanding skill. The submarine that had no confirmed sinkings on its first three patrols produced one of the most important single patrol results of the war on her first patrol. She also went on to sink the Japanese destroyer Shimatsuki on [clears throat] her third patrol, adding to a record that would have been remarkable even without the Shukaku sinking. The combination of the intelligence report and the carrier sinking represented exactly what the American submarine campaign was designed to produce information that could shape the broader battle and direct destructive power against the most valuable targets. The specific question of what the battle of the Philippine Sea settled was not fully apparent until the autumn of 1944 made it explicit. After the Philippine Sea, Japan had the Zuikaku and a reduced number of light carriers. It also had a much smaller number of trained pilots. The carriers could theoretically still operate, and they did operate at Laty Gulf in October of 1944. But the Laty Gulf operation revealed that Japan no longer had a carrier force in any meaningful tactical sense. The carriers at Late Gulf under Ozawa had barely enough aircraft to make a credible decoy force. They were there to be seen and attacked, not to fight.

[00:39:48]The loss at the Philippine Sea had reduced Japanese carrier aviation from a strategic offensive weapon to a sacrificial decoy. The Shukaku was one of the ships whose loss had produced that reduction. When she went under on June 19th, she took with her not only the dead, but also whatever Japanese carrier capacity she had represented.