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Titan submersible implosion -

A tourist submersible went missing during a dive to the Titanic's wreck on June 18. 2023. Five people were onboard when contact with the small sub was lost suddenly off the coast of St John’s, Newfoundland, about an hour and 45 minutes into its estimated two-hour journey nearly 13,000 ft underwater. A search and rescue mission was quickly launched but days passed with no sign of the sub as the precious oxygen supply dwindled.

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Titan submersible implosion -

On June 22, four days after the disappearance, the hopeless remains of the vessel were finally located on the ocean floor. The sub had fractured into five major fragments across a wide field of debris. Rear Admiral John Mauger of the US coast guard said that the wreckage indicates a "catastrophic implosion." The deceased passengers reportedly included OceanGate CEO and founder Stockton Rush, British businessman Hamish Harding, French diver Paul-Henri Nargeolet, and Pakistani billionaire Shahzada Dawood and his son, Suleman.

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The Kursk catastrophe -

The Russian nuclear submarine Kursk (K-141) was launched in 1994. She was named after the Second World War-era Battle of Kursk—a military engagement between the forces of Nazi Germany and the Soviet Union that became the largest tank battle in history.

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Gennady Lyachin -

The Kursk was skippered by Gennady Lyachin, seen here on the right in a video grab taken from the Russian television channel NTV.

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Explosion -

On August 10, 2000, the Kursk joined a large-scale Russian Navy exercise in the Barents Sea. Two days later, August 12, a huge explosion ripped through the submarine. The crippled vessel ended up on the seabed.

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118 dead -

It took more than 16 hours to locate the stricken submarine. Over the next four days, the Russian Navy repeatedly failed to attach diving bells and submersibles to the escape hatch of the boat. President Vladimir Putin, who refused to cut short his vacation, finally agreed after five days to accept British and Norwegian assistance. But by then it was too late. Any survivors of the initial blast were long dead. In all, 118 personnel lost their lives. Pictured is the conning tower of the Kursk after the submarine had been recovered from the seabed.

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Criticism -

The Russian government was roundly criticized for its inaction in the wake of the explosion. A report later concluded that the Russian Navy was completely unprepared to respond to the disaster. The photograph shows caskets containing the remains of four Kursk submariners arriving at the memorial service in the vessel's home port of Severomorsk.

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Sinking of the Surcouf -

The sinking of the French submarine Surcouf with the loss of all 130 crew is the worst submarine disaster in history.

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Robert Surcouf -

The Surcouf, named after French privateer, slave trader, and ship owner Robert Surcouf (1773–1827), was launched in November 1929.

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Inspection by de Gaulle -

She was a large, gun-armed cruiser submarine and served in the French Navy and, later, the Free French Naval Forces. She was a prestigious enough vessel to earn an inspection from General Charles de Gaulle in 1940.

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Was it a collision? -

Sometime during the night of February 18-19 1942, Surcouf disappeared. She likely accidentally collided with the American freighter Thompson Lykes. However, this has never been ascertained. The Thompson Lykes did report hitting something in the water, but thinking she'd run into a U-boat she continued her voyage.

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Wreck never found -

The submarine vanished in the Caribbean Sea about 130 km (70 mi) north of Cristóbal, Panama, while en route for Tahiti, via the Panama Canal (pictured). The wreck of the Surcouf has never been found.

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The fate of the USS Thresher -

Launched in 1960, the USS Thresher was an atomic-powered attack submarine. It was the fastest and quietest submarine of its day.

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Victim of deep-sea trials -

On April 10, 1963, Thresher sank during deep-dive trials east of Cape Cod, Massachusetts. The US Navy responded quickly, mounting an extensive search with surface ships and support from the Naval Research Laboratory, with its deep-search capability.

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Remains located -

A bathyscaphe, the Trieste (pictured), was launched to search the depths. After two days, the shattered remains of the lost submarine were found.

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Massive implosion blamed -

The Thresher was lying on the seabed 2,600 m (8,400 ft) below the surface. The cause of the accident was later blamed on a massive implosion due to flooding in the engine room.

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Second-deadliest sub incident -

All 129 crewmembers of Thresher perished in the accident, with some pictured here during a 50th anniversary memorial service. It is the second-deadliest submarine incident on record, after the 1942 loss of the French submarine Surcouf.

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Sinking of the Scorpion -

The mysterious disappearance of the nuclear-powered attack submarine USS Scorpion still baffles naval historians.

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Fleet and NATO exercises -

Launched in December 1959, Scorpion was based out of Norfolk, Virginia. Throughout much of the 1960s she participated in exercises with 6th Fleet units and NATO-member navies.

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Last photograph -

In February 1968, Scorpion departed Norfolk for a Mediterranean deployment. She docked alongside USS Tallahatchie County in Naples, Italy, in April 1968. This image is believed to be one of the last photographs taken of Scorpion before her loss.

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Lost in the Atlantic -

In May 1968, the submarine was reported missing in the Atlantic Ocean. Her wreckage was eventually located in October, about 644 km (400 mi) southwest of the Azores archipelago (Portugal), at a depth of 3,050 m (10,000 ft).  

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Reason for loss never given -

Various theories have been put forward as to the reasons behind the calamity, including a hydrogen explosion during a battery charge, accidental activation of a torpedo, and even a collision with a Soviet sub. What is certain is the loss of all 99 crew.

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Submarine K-19 -

The Soviet nuclear-powered submarine K-19 suffered several tragic setbacks during its near 30-year service. In 1961, a loss of coolant to one of its reactors nearly led to nuclear meltdown. Twenty-two crew members would eventually die in the attempt to plug a radioactive steam leak. This was the incident portrayed in the 2002 film 'K-19: The Widowmaker,' starring Harrison Ford and Liam Neeson. In 1969, the same sub collided with an American submarine in the Barents Sea, and in 1972 a fire broke out while the submarine was submerged, killing 28 crew.

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Submarine K-278 -

On April 7, 1989, the nuclear-powered Soviet submarine K-278 Komsomolets suffered a fire in its engine room while patrolling the Barents Sea off the coast of Norway. She managed to surface and remained afloat for five hours before sinking. Many of the crew perished before rescue, the total number of dead numbering 42.

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Submarine K-129 -

In March 1968 at the height of the Cold War, the diesel-electric powered Soviet submarine K-129 went missing in the Pacific Ocean. No plausible reason has ever been offered as to cause of loss, which resulted in the deaths of all 98 hands.

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Submarine 361 -

A mechanical failure on board the Chinese submarine 361 in April 2003 killed all 70 crew members. It was one of China's worst peacetime military disasters.

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Submarine Losharik -

In July 2019, a Russian nuclear-powered submarine designated Project 210 but nicknamed Losharik suffered an onboard fire while carrying out underwater measurements of the sea floor in Russian territorial waters. Fourteen crew members died, seven of whom held the rank of 1st captain.

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ARA San Juan -

The diesel-electric submarine ARA San Juan in service with the Argentine Navy went missing on November 15, 2017 during a routine patrol in the South Atlantic. A day later, the wreck of the hapless vessel was located at a depth of 907 m (2,976 ft), its imploded wreckage strewn across the seabed. The 44 crew all died as a result of a catastrophic explosion.

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Nerpa (K-152) -

Launched in 2008, the Russian nuclear-powered attack submarine Nerpa was undergoing a test run in the Pacific Ocean when a fire swept through the hull killing 20 people and injuring scores more. It remains the worst Russian submarine disaster since Kursk sank in 2000.

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KRI Nanggala (402) -

The Indonesian Navy suffered one of its worst losses of recent times when the KRI Nanggala (402) went missing during a routine exercise in the Bali Sea. It's believed the vessel suffered a power outage, which caused it to sink and eventually implode. All 52 crew on board perished.

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Submarine K-159 -

The Barents Sea claimed another Russian submarine in August 2003 when K-159 sank while under tow for scrapping. A skeleton crew of nine went down with her.

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HMS Thetis -

In a rare submarine accident recorded by the Royal Navy, HMS Thetis, a T-class vessel launched in 1939, sank during trials due to a flooded torpedo tube. Ninety-nine crew lost their lives. The submarine was salvaged and later saw action in the Second World War. She was lost with all hands in the Mediterranean on March 14, 1943.

See also: Historic ships and boats you can visit and admire

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