USS Samuel B. Roberts (DE-413) photographed in the beginning of summer 1944. It is the deepest lying shipwreck known currently in the world. Photo: U.S. Naval History and Heritage Command

Shipwrecks in the greatest depths

 Text: Miro Barič

In this last installement of searching for the lost ships with Paul Alled we will talk about the shipwrecks lying in the greatest depths of the world. They sank to the bottom of the ocean during the Battle of Samar. These are the American destroyers which, heavily outnumbered, bravely faced the enemy for whom this battle was a swan song.

The Battle of Santa Cruz, during which the aircraft carrier USS Hornet (CV-8) was sunk in October 1942, was for a long time the last carriers encounter. While the Allies gradually took over the strategic initiative, the Japanese carriers were recovering from the losses. The damaged ships needed repairs but above all the lost aircraft had to be replenished and new pilots trained. During the whole 1943 no further aircraft carriers battle took place. The Japanese Navy was saving the resources and preparing for the so-called decisive battle. The opportunity arrived in June 1944 when the US carriers attacked the Mariana Islands. The Japanese threw all they had into the counter attack – 1st Mobile Fleet formed by total of 83 vessels, including 3 large aircraft carriers, 6 light aircraft carriers and 5 battleships. They faced the American 5th Fleet composed of 139 ships. The backbone of the US fleet was formed by 7 large aircraft carriers, 8 light aircraft carriers and 7 battleships. The American dominance was to be compensated by deployment of further 300 Japanese aircraft operating from the land bases.

The result of the Battle of Philippine Sea doesn’t need a detailed description, its first day went down in the history as a Great Mariana Turkey Shoot. The great lack of quality in Japanese aircraft and pilots‘ training was aparent and the Japanese aircraft were falling of the skies in hundreds. One of the American pilots described the combat after landing as shooting turkeys back home in old times. The greatest American fighter aces increased their scores thanks to it. Cdr. David McCampbell, who up until then was credited with two kills (out of total 34), on June 19, 1944, during his first sortie, shot down fine D4Y Judy dive bombers and during the next sortie added two A6M fighters. Lt. Alexander Vraciu, whose score stood at 12 kills at that time (out of total 19), on the same day during one sortie shot down six D4Y Judy bombers. It took him eight minutes and he spent 360 12.7 mm caliber rounds.

While the American pilots fought the Japanese aircraft, on that day the Japanese ships were only attacked by the American submarines. They fared very well indeed. USS Cavalla hit Shokaku with three torpedoes and sank her. USS Albacore hit the new carrier Taiho with only a single torpedo but a poor execution of the rescue operations caused the fuel fumes to accumulate under the deck which later caused a series of explosions and Taiho sank as well. The aircraft from the American carriers attacked the Japanese vessels on June 20, 1944, at the limit of their range and almost at night. They sank light carrier Hiyo and two tankers. They also damaged several other ships. However, they paid the price by loosing 100 aircraft, only 20 were shot down in combat tough. The remaining 80 had to crash land due to the lack of fuel and the crews were mostly rescued. The Japanese losses were significantly higher. The air forces they had gathered during the whole previous year, were lost in two days. The remaining Japanese aircraft carriers without airplanes could not longer play an active role and in the following battle they were used as decoy.

L.(jg) Alexander Vraciu shows his six fingers for the aerial kills he scored on June 19, 1944. Photo: National Archives

Cdr. David McCampbell in the cockpit of his Hellcat on board of USS Essex in the beginning of October 1944. At that time his score stood at 21 kills. Foto: U.S. Navy

 McCampbell is posing in the cockpit of his Hellcat for a propaganda photograph in the end of October 1944. By scoring additional 9 kills in a day, he raised his score to 30 victories. Foto: U.S. Navy

Four battles in one

It took place during the Philippines landing in October 1944. Actually there was a series of several naval battles which became to be known under the common name, the Battle of Leyte Gulf. The Japanese Navy did not recover from the preceding defeats but had to react to the Allied invasion. The Japanese deployed the old samurai tactics of the feign attack. The Northern Force, commanded by Vice Admiral Ozawa, assumed the role of a decoy. On the paper it looked strong composed of two battleships, aircraft carrier Zuikaku and three light carrier Zuiho, Chiyoda and Chitose, however they altogether carried 108 aircraft only. In the meantime, the Center Force led by Viceadmiral Kurita and Southern Force consisting of two groups led by Viceadmirals Nishimura and Shima were to approach the Allied invasion fleet through different passages. They were at the disadvantage though due to the strict radio silence and the admirals were unable to coordinate their actions and each of them acted individually. Therefore they gradually clashed with the US Navy in four battles.

The first one took place in Sibuyan Sea. First, on October 23, 1944, Kurita’s Center Force was spotted and attacked by the American submarines USS Darter and USS Dace. They sank two heavy cruisers and damaged another one. Then, on October 24, 1944, the Japanese ships became targets of five waves of the American carrier-borne aircraft. Those sank the battleship Musashi and damaged several other ships. Kurita therefore turned around 180 degrees and started to retreat, and the Americans took the bait. Musashi’s wreck was one of the first Paul Allen found. It happened in March 2015 using his older ship Octopus. Musashi lies 900 meters deep and Allen’s expedition discovered that she had exploded while sinking. The bow stands upright on the ocean’s bottom and the stern is turned upside down. The main superstructure and stack lie on the sides.

USS Samuel B. Roberts (DE-413) in October 1944, couple of days before her sinking. Photo: U.S. Naval History and Heritage Command

LCdr. Robert Copeland, commanding officer of Samuel B. Roberts escort destroyer. Photo: U.S. Naval History and Heritage Command

USS Johnston (DD-557) in October 1943, right after her entry in the service. Photo: U.S. Navy

Cdr. Ernest Evans, commanding officer of destroyer Johnston. Photo: U.S. Naval History and Heritage Command

Nine kills in one sortie          

In the meantime, three waves of Japanese airplanes from the land bases attacked the American ships. During their defenses Cdr. David McCampbell distinguished himself again. Only in a pair formation, just with his wingman, he attacked the formation of 60-80 airplanes approaching the American ships. In the combat, which lasted an hour and 35 minutes, he shot down 9 Japanese fighters and two probables. His wingman, Lt. Roy Rushing was credited with another six kills. They completely dismantled the Japanese formation. After the landing the mechanics did not find any fuel left in Campbell Hellcat’s tanks and there were two 12.7 mm caliber rounds left for his machine guns. For this achievement, as well as the previous success in the Battle of Philippine Sea four months ago , McCambell was decorated with the highest American award, Medal of Honour. The rare success by the Japanese side was scored by a D4Y Judy dive bomber which penetrated the defences and suddenly appeared above the light aircraft carrier USS Princeton. Its bomb exploded in the hangar among fully fueled Avenger bombers. The result was a fire which after several hours caused an enormous explosion of the stored bombs. The ship was impossible to rescue and she sank with 108 souls lost. Further 233 American sailors perished on board of the light cruiser USS Birmingham which was at the time of Princeton explosion at her side helping with putting out the fires.

USS Hoel (DD-533) in August 1944. Photo: U.S. Naval History and Heritage Command

The American destroyers and escort destroyers laying the smoke screen during the Battle of Samar. Photo: U.S. Navy

Battle of Surigao Strait

In the meantime the Japanese Southern Force tried to fight its way through Surigao Strait. On October 24, 1944 the American airplanes barely caused any damage to Nishimura’s ships but the American vessels set up a trap for him in the strait. First he faced the attack of the torpedo boats and destroyers. Those sank the battleship Fuso. Six battleships and eight cruisers under the command of Admiral Oldendorf waited for the Japanese at the exit from the strait. On December 7, 1941, five of these battleships were sunk or damaged at Pearl Harbor. California, Maryland, Pennsylvania, Tennessee and West Virginia then underwent the extensive repairs and rebuilds. On the night of October 24-25, 1944, time of their revenge arrived. Their radar-controlled cannon fire sank Yamashiro and damaged the cruiser Mogami. It was the last battleship encounter in the history.

The second part of the Southern Force did not engage in this battle because it lagged behind Nishimura. When Shima realized that the first part had been massacred, he ordered a retreat. At that moment, Mogami collided with the heavy cruiser Nachi and was further damaged. This heavy cruiser met a similar fate in the Battle of Midway when it collided with its sister ship, Mikuma. The collision slowed down both ships, making them vulnerable to the dive bombers, and Mikuma was eventually sunk. Though Mogami survived Midway, it was so severely damaged that they had to remove its rear turrets and rebuild it as a hybrid cruiser – a seaplane carrier. Now, after the collision with Nachi, its fate was sealed. The pursuing American cruisers inflicted further damage on Mogami, and in the morning, it was finished off by bombs from an Avenger bomber.

The wrecks of Yamashiro and Fusō were discovered by Paul Allen and his ship RV Petrel on November 25, 2017. Both ships lie upside down at a depth of around 200 meters. On May 8, 2019, RV Petrel also found the wreck of the cruiser Mogami, which lies at a depth of 1450 meters.

USS Gambier Bay (CVE-73) in April 1944. Photo: U.S. Naval History and Heritage Command

Battle of Cape Engaño

Although Ozawa’s Northern Force with aircraft carriers tried to attract the attention of the Americans, they only discovered it last, in the evening of October 24, 1944. However, this turned out to be coincidentally perfect timing for the Japanese. At the same time, Kurita's Center Force had turned back in retreat. American Admiral William Halsey was convinced that Kurita’s ships were out of action and focused on Ozawa.

The final battle of the aircraft carriers took place on October 25, 1944. Early in the morning, Ozawa launched an attack wave of 75 aircraft. That was all the Japanese aircraft carriers could muster, having been decimated in previous battles. Most of these planes were shot down, and Ozawa had no more left. Subsequently, he had to face six waves of American attacks, which sank all four Japanese aircraft carriers.

USS Gambier Bay photographed from the deck of USS Kalinin Bay during the Battle of Samar. Photo: U.S. Naval History and Heritage Command

The Battle of Samar Island

The Japanese original plan almost succeeded. While the Japanese aircraft carriers were being used as a bait and being massacred, the core of Kurita’s Center Force appeared near the invasion beaches. Kurita had feigned a retreat and then turned back to his original course, sneaking through the San Bernardino Strait unnoticed during the night. American Admiral William Halsey sent his main forces north against Ozawa, leaving the strait unguarded. Another mistake made by Halsey was his delayed reaction to reports of the Japanese battleships' penetration; he was too eager to destroy the enemy’s aircraft carriers. Unfortunately, this exposed the entire Philippine landing to a deadly risk.

Against four Japanese battleships, six heavy cruisers, and eleven destroyers, there were only three groups of small and slow escort aircraft carriers providing support to the landing forces – Taffy 1, Taffy 2, and Taffy 3. When the Japanese ships appeared on the horizon, Taffy 3, commanded by Admiral Clifton Sprague, was the closest to them. The group consisted of six escort carriers (Fanshaw Bay, Gambier Bay, Kalinin Bay, Kitkun Bay, St. Lo, and White Plains), three destroyers (Heermann, Hoel, and Johnston), and four escort destroyers (Dennis, John C. Butler, Raymond, and Samuel B. Roberts). The destroyers of the Fletcher class, armed with five 127mm guns and ten torpedo tubes, were the most heavily armed ships in Taffy 3. The escort destroyers were smaller and slower, carrying only two 127mm guns and three torpedo launchers. To put it in perspective, the battleship Yamato had a larger displacement than the entire American force combined!

In the ensuing battle of David against Goliath, the Japanese cruisers Chōkai, Chikuma, and Suzuya were sunk, while on the American side, the destroyers USS Johnston, USS Hoel, and USS Samuel B. Roberts were lost. The escort carrier USS Gambier Bay was destroyed by gunfire from the cruisers Tone and Chikuma. It was the only American aircraft carrier sunk by surface gunfire. After the battle with Kurita's forces, the heavily tested Taffy 3 group had to face the first organized kamikaze attack. Several ships were damaged, and the escort carrier USS St. Lo was sunk when a Zero carrying a bomb crashed into its flight deck and exploded in the hangar among refueling aircraft.

The total American losses in the Battle of Samar Island were nearly 1,200 sailors and aviators, which is more than the casualties in the Battles of Midway and the Coral Sea combined. It is no wonder that Clifton Sprague harshly criticized Halsey's actions.

The Battle of Samar Island is renowned as the “finest hour of the U.S. Navy,” and more detailed information about it can be found in Tom Cleaver’s article on page ?? of this issue. Now, let’s focus on the wrecks of the ships left behind after the battle...

Gambier Bay lagged behind the rest of the group. In the picture we can see as the Japanese grenades exploding aorund her. Photo: U.S. Naval History and Heritage Command

Saving the survivors of the Battle of Samar. Photo: U.S. Naval History and Heritage Command

In the Philippine Trench

The Battle of Samar Island took place on the edge of the Philippine Trench, and as a result, all the sunken ships rest in great depths. The wreck of USS St. Lo was discovered by the research vessel RV Petrel in May 2019, lying at a depth of 4,736 meters. In the same month, researchers also located the cruiser Chōkai at a depth of 5,173 meters.

However, in October 2019, RV Petrel found parts of a ship believed to be from USS Johnston. They were located at a depth of 6,218 meters, making it the deepest known shipwreck at that time. The discovery included a gun, a propeller shaft, and several other fragments. Indications on the seabed suggested that the rest of the ship had sunk even deeper, beyond the reach of the exploration robot.

Enter Victor Vescovo, an entrepreneur and investor who served in the U.S. Navy for 20 years and now dedicates himself to deep-sea expeditions. He has dived to the deepest points in all the world's oceans, including reaching the bottom of the Mariana Trench's Challenger Deep in April 2019. It was only the third manned mission to this location in history.

On March 31, 2021, Vescovo’s research vessel DSV Limiting Factor found the remaining wreckage of USS Johnston at a depth of 6,469 meters, definitively identifying it. This discovery set a new record for the deepest known shipwreck.

However, this record was broken again in June 2021 when Vescovo and his team found the wreck of the escort destroyer USS Samuel B. Roberts at a depth of 6,895 meters. According to their observations, the ship descended in one piece before crashing onto the seabed with its bow first, causing hull deformations and the detachment of the stern, which now lies 5 meters away from the main wreck. The hull also bears visible damage caused by Japanese shelling, including a broken mast.

Currently, the USS Samuel B. Roberts holds the title of the deepest known shipwreck. Still, it is believed that some of the ships sunk in the Battle of Samar Island lie even deeper. Searching for them in the depths of the Philippine Trench is extremely challenging. USS Gambier Bay and USS Hoel are yet to be found, with the destroyer potentially resting at a depth of up to 7,300 meters. Even deeper is presumed to be the Japanese cruiser Suzuya, which is believed to lie at a depth of up to 8,400 meters.

Number 413 seen on the shipwreck of escort destroyer USS Samuel B. Roberts. Photo: Victor Vescovo

Broken stern of USS Samuel B. Roberts. Photo: Victor Vescovo

 The rear gun turret of USS Samuel B. Roberts featuring the 127 mm caliber cannon. Photo: Victor Vescovo

The captain‘s bridge of USS Samuel B. Roberts. Twin barrel of the 40 mm caliber cannon can be seen on the starboard and 20 mm cannon on the port. Photo: Victor Vescovo

USS Samuel B. Roberts‘ bow.  Photo: Victor Vescovo

The number 557 can be seen on the hull of destroyer USS Johnston.  Photo: Victor Vescovo

A gun turret featuring 127 mm caliber cannon on board of USS Johnston. Photo: Victor Vescovo

End of RV Petrel?

The fate of the research vessel RV Petrel has become a symbolic conclusion to the series of discoveries mentioned earlier. After Paul Allen's passing on October 15, 2018, the RV Petrel continued her work. Its crew discovered many wrecks mentioned in our articles published in 2019. At the beginning of 2020, several expeditions were undertaken as part of a partnership between the National Oceanic and Atmospheric Administration (NOAA) and the Paul G. Allen Family Foundation.

In June 2020, the RV Petrel underwent modernization and was equipped with new instruments. However, due to the COVID-19 pandemic, it was put into indefinite storage in a dry dock in Scotland. In October 2022, the United States Navy purchased the vessel for $12.4 million. Nonetheless, it remained in the dry dock at the port of Leith in Edinburgh.

Tragedy struck on March 22, 2023, during strong winds, when the RV Petrel broke free from its moorings and capsized at a 45-degree angle. 33 people were injured, but luckily there were no fatalities. The extent of the damage and the future of the vessel remain unknown at this time.