Ill-fated Titanic submersible's last journey: When did it go missing and key events in search
The passengers on board the Titan sub are believed to be dead, the vessel's operator says
Here is a timeline of events since the start of the trip, organised by OceanGate Expeditions, to visit the Titanic wreckage:
Thursday, June 22
The five people aboard a submersible visiting the wreckage of the Titanic died beneath two miles of ocean after a "debris field" matching the missing submersible was discovered by a robotic deep-sea vessel.
The five people aboard included the British billionaire and explorer Hamish Harding, 58; Pakistani-born business magnate Shahzada Dawood, 48, and his 19-year-old son, Suleman, both British citizens; French oceanographer and Titanic expert Paul-Henri Nargeolet, 77, who had visited the wreck dozens of times; and Stockton Rush, the American founder and chief executive of OceanGate, who was piloting the submersible.
Thursday, June 22
(6 a.m. ET) - Rough deadline for when the air in the submersible will run out, based on the U.S. Coast Guard's estimate. The vessel has 96 hours of air supply from the time it is sealed, according to its specifications. This depends on the vessel being intact and other factors, such as whether the sub still has power in the icy depths.
1800 GMT (2 p.m. ET) - A debris field that was found near the wreckage of the Titanic in the North Atlantic contains the pieces of the Titan submersible, officials said.
1900 GMT (3 p.m. ET) - The debris was consistent with a catastrophic loss of the pressure chamber and an implosion, the US Coast Guard said. There were no survivors.
Late on Wednesday, June 21
French research ship, equipped with a deep-sea diving vessel, expected to arrive at search area.
Tuesday, June 20
The family of Pakistani-born businessman Shahzada Dawood confirm he is aboard with his 19-year-old son Suleman.
They ask for prayers for their safety.
1450 GMT (10.50 a.m. ET)- France says it will help with search by deploying Atalante, a ship equipped with a deep-sea diving vessel and managed by the Ifremer ocean research institute.
During the day - Sounds were detected over several hours by Canadian Lockheed P-3 Orion aircraft, equipped with gear to trace submarines. The US Coast Guard - which announces this on Wednesday - does not give a precise timing.
CNN and Rolling Stone magazine reports Canadian aircraft detected banging sounds at 30-minute intervals. Rolling Stone says sonar picks up more banging four hours later. CNN also reports later sounds but does not describe them as banging.
Harding's friend, Jannicke Mikkelsen, says: "And as it stands right now, it would be a miracle if they are recovered alive."
Monday, June 19
US and Canadian ships and planes are swarming the area, some dropping sonar buoys that can monitor to a depth of 13,000 feet (3,962 meters), US Coast Guard Rear Admiral John Mauger says. He adds it is a remote area and a challenge to conduct a search. Officials have also asked commercial vessels for help.
Sunday, June 18
0800 GMT (4 am ET) - Time the submersible originally aimed to start its descent, according to a post by Harding on Instagram.
But it starts its descent later, according to the US Coast Guard.
1200 GMT (8 am ET) - Titan submersible starts what should be a two-hour descent to the Titanic wreck, which lies at a depth of 12,500 feet (3,810 meters) in the North Atlantic, US Coast Guard says.
1345 GMT (9.45 am ET) - Communications between the submersible and the surface vessel are lost 1 hour and 45 minutes after starting its descent, the US Coast Guard says.
1900 GMT (3 pm ET) - The submersible is scheduled to return to the surface, the US Coast Guard says. It fails to appear.
2140 GMT (5.40 pm ET) - Coast Guard receives report about an overdue submersible from the Canadian Research Vessel Polar Prince with five people aboard diving to view the Titanic wreck about 900 nautical miles east of Cape Cod on the US coast.
Saturday, June 17
Saturday evening British billionaire and adventurer Hamish Harding, one of those aboard the submersible, posts on Facebook: "Due to the worst winter in Newfoundland in 40 years, this mission is likely to be the first and only manned mission to the Titanic in 2023. A weather window has just opened up and we are going to attempt a dive tomorrow." "More expedition updates to follow IF the weather holds!" He does not post again on Facebook.
Friday, June 16
Expedition sets off from St. John's, Newfoundland, Canada.