Teams searching for the submersible that went missing during a voyage to Titanic can draw on a number of successful rescue operations in the past.
In one of the largest rescue missions in history in 1939, about 33 men from the US submarine Squalus were rescued after their ship sank 240 feet under the sea.
As rescue efforts continue off Newfoundland for the wrecked tourist submarine Titanic, here’s a look at six famous stories on or under the water:
Harrison Okene – Survived nearly three days in an air bubble
Harrison Okene survived nearly three days underwater by squatting in an air bubble in May 2013 after his tug boat capsized about 20 miles off the Nigerian coast.
The chef, who was the sole survivor of a crew of 12, survived for 62 hours on the bottom of the Atlantic Ocean with a single bottle of Coca-Cola to quench his thirst.
His boat capsized and later ended up lying upside down on the sea floor at a depth of about 100 feet (30 m), but he was able to survive in the air pocket until rescuers reached him.
Mr Okene said he could smell the bodies of his crew members and hear horribly fish eating them as he tried to stay afloat.
The two flashlights he found broke in less than a day, but he was eventually rescued by deep sea divers who discovered the wreck.
A video captured the amazing moment he was found, as he reached out and touched one of the rescue team members to let them know he was alive.
Mr Okene suffered from nightmares after his ordeal and vowed never to go into the sea again – but he has since been a commercial air diver at depths of 165ft (50m).
Roger Mallinson and Roger Chapman – saved with 12 minutes to go
Things were looking serious for Roger Mallinson, 35, and Roger Chapman, 28, when their mini-submarine crashed 1,575 feet below the surface after 80 hours of flight.
The duo had been working under the Atlantic Ocean 150 miles off the coast of Cork, Ireland, laying a telephone cable on the ship Pisces III in August 1973.
After being hoisted to the surface, a defective hatch to a locked compartment ruptured, water poured in and it sank straight down, breaking the connecting cable along the way.
The boat was impaled in the seabed and submarine operators had to change carbon dioxide filters every hour to avoid asphyxiation, using two clockwork timers as alarms.
The rescue involved three submarines, several ships, airplanes and helicopters, which eventually resulted in her being hauled up with only 12 minutes of oxygen supply left.
Mr. Chapman then developed the use of unmanned submarines. Mr Mallinson admitted how difficult it was: “None of us really thought we were going to get out.”
Rolando Omongos – Rescued after two months on a tiny boat
A young fisherman from the Philippines was left to die at sea, fighting hunger, thirst and despair on a tiny boat for nearly two months. Rolando Omongos, who was 21 when his ship drifted as far as Papua New Guinea, was eventually rescued by a Japanese ship in 2017.
He said he survived on rainwater and moss growing on the hull of his 8-foot boat and found shelter from the sun’s heat by frequent diving in the water.
His 31-year-old uncle, Reniel Omongos, who was on a second small boat, died after a month. Rolando thought hunger and cold had killed him.
The relatives had left in December 2016 with other fishermen aboard a purse seine vessel from General Santos, a southern Philippine port overlooking the Celebes Sea.
A storm separated Rolando and his uncle from their mother boat in January 2017 and five days later they ran out of fuel. But he said, “I never lost hope.”
Jose Salvador Alvarenga – Castaway survived 438 days at sea
Shipwrecked man Jose Salvador Alvarenga survived 438 days at sea and claimed he survived by drinking urine and turtle blood and eating fish and birds he caught.
The El Salvador tuna fisherman washed ashore in the Marshall Islands in January 2014 after being 6,700 miles from the coast of Mexico since November 2012.
The boat he and crewmate Ezequiel Cordoba were sailing in was paralyzed by a storm, but Mr Alvarenga later recounted how his best friend starved to death.
Mr Cordoba’s family made sensational claims that he was a victim of cannibalism, but Mr Alvarenga denied this and said he threw the body into the water.
After his ordeal, he did surprisingly well, claiming that he became so hungry that he took jellyfish out of the water and ate them whole.
Mr Alvarenga later said he almost gave up hope of rescue after several large vessels came near his small fishing boat, but none attempted to rescue him.
Brett Archibald – swam 29 hours without a life jacket
Brett Archibald fell overboard from a tour boat in Indonesia in 2013 and drifted 11 miles but survived by floating for 29 hours – despite not wearing a life jacket.
The South African father-of-two said he came close to drowning at least eight times during the ordeal, which saw him stung by jellyfish and attacked by seagulls.
Mr Archibald was eventually pulled from the Mentawai Strait by Australian surfer Dave Carbon with a dangerously low blood pressure of 68/44.
His face and head were badly burned, his tongue was stuffed up, his eyes were red and painful, and his nose had a huge hole where the seagulls had pecked.
A few months after his ordeal, he suffered two severe panic attacks, but he began speaking publicly about his experiences and raising money for charity.
Mr Archibald also wrote about his horrifying story in a book called Alone: Lost Overboard In The Indian Ocean, which was released as a sequel in 2016.