On June 18, 2023, Titan, a submersible operated by the American tourism and expeditions company OceanGate, imploded during an expedition to view the wreck of the Titanic in the North Atlantic Ocean off the coast of Newfoundland, Canada. Aboard the submersible were Stockton Rush, the American chief executive officer of OceanGate; Paul-Henri Nargeolet, a French deep-sea explorer and Titanic expert; Hamish Harding, a British businessman; Shahzada Dawood, a Pakistani-British businessman; and Dawood's son, Suleman.
Communication between Titan and its mother ship, MV Polar Prince, was lost 1 hour and 33 minutes into the dive. Authorities were alerted when it failed to resurface at the scheduled time later that day. After the submersible had been missing for four days, a remotely operated underwater vehicle (ROV) discovered a debris field containing parts of Titan, about 550 yards (500 m; 1,650 ft) from the bow of Titanic. The search area was informed by the United States Navy's (USN) sonar detection of an acoustic signature consistent with an implosion around the time communications with the submersible ceased, suggesting the pressure hull had imploded while Titan was descending, resulting in the instant death of all five occupants.
The search and rescue operation was performed by an international team organized by the United States Coast Guard (USCG), USN, and Canadian Coast Guard. Support was provided by aircraft from the Royal Canadian Air Force and United States Air National Guard, a Royal Canadian Navy ship, as well as several commercial and research vessels and ROVs.
Industry experts, friends of Rush, and OceanGate employees had previously stated concerns about the safety of the vessel.
Background
OceanGate
OceanGate, a private company, was initiated in 2009 by Stockton Rush and Guillermo Söhnlein. From 2010 until the loss of the Titan submersible, OceanGate had transported paying customers in leased commercial submersibles off the coast of California, in the Gulf of Mexico, and in the Atlantic Ocean. The company was based in Everett, Washington, US.
Rush realized that visiting shipwreck sites was a method of getting media attention. OceanGate had previously conducted voyages to other shipwrecks, including its 2016 dive to the wreck of Andrea Doria aboard their other submersible Cyclops 1. (A near disaster on that expedition was recounted in Vanity Fair in 2023.) In 2019, Rush told Smithsonian magazine: "There's only one wreck that everyone knows ... If you ask people to name something underwater, it's going to be sharks, whales, Titanic."
Titanic
The Titanic was a British ocean liner that sank in the North Atlantic Ocean on April 15, 1912, after colliding with an iceberg. More than 1,500 people died, making it the deadliest sinking of a single ship at the time. In 1985, Robert Ballard located the wreck of the Titanic 320 nautical miles (590 km; 370 mi) from the coast of Newfoundland. The Titanic's wreck lies at a depth of 2,100 fathoms (12,600 ft; 3,800 m). Since its discovery, it has been a destination for research expeditions and tourism. By 2012, 140 people had visited the wreck site.
The Titan submersible
Formerly known as Cyclops 2, Titan was a five-person submersible vessel operated by OceanGate Inc. The 6.7-metre (22 ft), 10,432-kilogram (10.4 t; 23,000 lb) vessel was constructed from carbon fibre and titanium. The entire pressure vessel consisted of two titanium hemispheres (domes) with matching titanium interface rings bonded to the 142-centimetre (56 in) internal diameter, 2.4-metre (7.9 ft) carbon fibre-wound cylinder. One of the titanium hemispherical end caps was detachable to provide the hatch and was fitted with a 380-millimetre-diameter (15 in) acrylic window. In 2020, Rush said that the hull, originally designed to reach 4,000 m (13,000 ft) below sea level, had been downgraded to a depth rating of 3,000 m (9,800 ft) after demonstrating signs of cyclic fatigue. In 2020 and 2021, the hull was repaired or rebuilt. Rush told the Travel Weekly editor-in-chief that the carbon fibre had been sourced at a discount from Boeing because it was too old for use in the company's airplanes. Boeing stated they have no records of any sale to Rush or to OceanGate. OceanGate had initially not sought certification for Titan, arguing that excessive safety protocols hindered innovation. Lloyd's Register, a ship classification society, refused OceanGate's request to class the vessel in 2019.
Titan could move at as much as 3 knots (5.6 km/h; 3.5 mph) using four electric thrusters, arrayed two horizontal and two vertical. Its steering controls consisted of a Logitech F710 wireless game controller with modified longer analog sticks resembling traditional joysticks. The University of Washington's Applied Physics Laboratory assisted with the control design on the Cyclops 1 using a DualShock 3 video game controller, which was carried over to Titan, substituting with the Logitech controller. The use of commercial off-the-shelf game controllers is common for remote-controlled vehicles such as unmanned aerial vehicles or bomb disposal robots, while the United States Navy uses Xbox 360 controllers to control periscopes in Virginia-class submarines.
OceanGate claimed on its website as of 2023 that Titan was "designed and engineered by OceanGate Inc. in collaboration [with] experts from NASA, Boeing, and the University of Washington" (UW). A 1⁄3-scale model of the Cyclops 2 pressure vessel was built and tested at the Applied Physics Laboratory (APL) at UW; the model was able to sustain a pressure of 291.6 standard atmospheres (29.54 MPa; 4,285 psi), corresponding to a depth of about 3,000 m (9,800 ft). After the disappearance of Titan in 2023, earlier associates disclaimed involvement with the Titan project. UW claimed the APL had no involvement in the "design, engineering, or testing of the Titan submersible". A Boeing spokesperson also claimed Boeing "was not a partner on Titan and did not design or build it". A NASA spokesperson said that NASA's Marshall Space Flight Center had a Space Act Agreement with OceanGate, but "did not conduct testing and manufacturing via its workforce or facilities".
It was designed and developed originally in partnership with UW and Boeing, both of which put forth numerous design recommendations and rigorous testing requirements, which Rush ignored, despite prior tests at lower depths resulting in implosions at the UW lab. These partnerships dissolved as Rush refused to work within quality standards.
According to OceanGate, the vessel contained monitoring systems to continuously monitor the strength of the hull. The vessel had life support for five people for 96 hours. GPS signals cannot be received underwater; instead, the support ship and Titan used an ultra-short baseline (USBL) acoustic positioning system to determine their relative distance and bearing. The same system could be used to send very short text messages between the two craft.
According to OceanGate, Titan had several backup systems intended to return the vessel to the surface in case of emergency, including ballasts that could be dropped, a balloon, thrusters, and sandbags held by hooks designed to dissolve after a certain number of hours in saltwater, releasing the sandbags and allowing the vessel to float to the surface. An OceanGate investor explained that if the vessel did not ascend automatically after the elapsed time, those inside could help release the ballast either by tilting the ship back and forth to dislodge it or by using a pneumatic pump to loosen the weights.
Dives to wreck of Titanic
Dives by Titan to the wreck of Titanic occurred as part of multi-day excursions organized by OceanGate, which the company referred to as "missions". Five missions per year occurred in the middle of 2021 and 2022. Titan imploded during the fifth mission of 2023; none of the four earlier that year got close to Titanic, largely because of rough weather. YouTuber Jake Koehler was invited to vlog the submersible's Mission III, which did not dive due to poor weather, a ghost net wrapping around and destroying some of the submersible's parts, and the motor controllers malfunctioning. Following the submersible's implosion, Koehler uploaded a YouTube video documenting his experience.
Passengers would sail to and from the wreckage site aboard a support ship and spend approximately five days on the ocean above the Titanic wreckage site. Two dives were usually attempted during each excursion, though dives were often cancelled or aborted due to weather or technical malfunctions.
Each dive typically had a pilot, a guide, and three paying passengers aboard. Once they were inside the submersible, the hatch would be bolted shut and could only be reopened from the outside. The descent from the surface to the Titanic wreck typically took two hours, with the full dive taking about eight hours. Throughout the journey, the submersible's acoustic positioning system sent automated location updates ("pings") to the surface team's tracking equipment every 5 to 10 seconds; the two vessels were also expected to send "comms check" text messages every 15 minutes.
Customers who travelled to the wreck with OceanGate, referred to as "mission specialists" by the company, paid US$250,000 each for the eight-day expedition.
Safety
Because Titan operated in international waters and did not carry passengers from a port, it was not subject to safety regulations. The vessel was not certified as seaworthy by any regulatory agency or third-party organization. Reporter David Pogue, who completed the expedition in 2022 as part of a CBS News Sunday Morning feature, said that all passengers who enter Titan sign a waiver confirming their knowledge that it is an "experimental" vessel "that has not been approved or certified by any regulatory body, and could result in physical injury, disability, emotional trauma or death". Television producer Mike Reiss, who also completed the expedition, said the waiver "mention[s] death three times on page one". A 2019 article published in Smithsonian magazine referred to Rush as a "daredevil inventor". In the article, Rush is described as having said that the US Passenger Vessel Safety Act of 1993 "needlessly prioritized passenger safety over commercial innovation". In a 2022 interview, Rush told CBS News, "At some point, safety just is pure waste. I mean, if you just want to be safe, don't get out of bed. Don't get in your car. Don't do anything." Rush said in a 2021 interview, "I've broken some rules to make [Titan]. I think I've broken them with logic and good engineering behind me. The carbon fibre and titanium, there's a rule you don't do that. Well, I did."
OceanGate claimed that Titan was the only crewed submersible that used an integrated real-time monitoring system (RTM) for safety. The proprietary system, patented by Rush in 2021, used acoustic sensors and strain gauges at the pressure boundary to analyse the effects of increasing pressure as the watercraft ventured deeper into the ocean and to monitor the hull's integrity in real time. This would supposedly give early warning of problems and allow enough time to abort the descent and return to the surface.
Prior concerns
In 2018, OceanGate's director of marine operations, David Lochridge, composed a report documenting safety concerns he had about Titan. In court documents, Lochridge said that he had urged the company to have Titan assessed and certified by the American Bureau of Shipping, but OceanGate had refused to do so, instead seeking classification from Lloyd's Register. He also said that the transparent viewport on its forward end, due to its nonstandard and therefore experimental design, was only certified to a depth of 1,300 m (4,300 ft), only a third of the depth required to reach the Titanic's wreck. According to Lochridge, RTM would "only show when a component is about to fail – often milliseconds before an implosion" and could not detect existing flaws in the hull before it was too late. Lochridge was also concerned that OceanGate would not perform nondestructive testing on the vessel's hull before undertaking crewed dives and alleged that he was "repeatedly told that no scan of the hull or Bond Line could be done to check for delaminations, porosity and voids of sufficient adhesion of the glue being used due to the thickness of the hull". The viewport was rated to only 650 m (2,130 ft), and the engineer of the viewport also prepared an analysis from an independent expert that concluded the design would fail after only a few 4,000 m (13,000 ft) dives.
OceanGate said that Lochridge, who was not an engineer, had refused to accept safety approvals from OceanGate's engineering team and that the company's evaluation of Titan's hull was stronger than any kind of third-party evaluation Lochridge thought necessary. OceanGate sued Lochridge for allegedly breaching his confidentiality contract and making fraudulent statements. Lochridge counter-sued, stating that his employment had been wrongfully terminated as a whistleblower for stating concerns about Titan's ability to operate safely. The two parties settled the case a few months later, before it came to court. Lochridge also filed a whistleblower complaint with Occupational Safety and Health Administration, but withdrew it after the lawsuit was filed.