Missing Titanic submersible: what is the Titan tourist sub and what might have happened to it? | The Titanic

Search and rescue teams are racing to find a tourist submersible that went missing with five people on board during a dive to explore the wreck of the Titanic.

Contact with the Titan submersible was lost 1 hour 45 minutes into its dive on Sunday afternoon, according to the US Coast Guard. Here’s what we know about the vessel and what might have happened.

What is the Titan sub and what can it do?

The Titan is a research and survey submersible that can carry five people, usually a pilot and four “mission specialists” who can include archaeologists, marine biologists or anyone who can afford the experience as a tourist.

Made of “titanium and filament wound carbon fibre”, the 6.7-metre (22ft) craft weighs 10,432kg (23,000lbs), equivalent to about six average-size cars, and is capable of diving to depths of 4,000 metres (13,120ft) “with a comfortable safety margin”, according to operator OceanGate. It uses four electric thrusters to move around, and has a battery of cameras, lights and scanners to explore its environment. OceanGate says Titan’s viewport is “the largest of any deep diving submersible” and that its technology provides an “unrivalled view” of the deep ocean. It uses Elon Musk’s Starlink satellite technology to communicate, though it is unclear if it was the cause of the loss of contact. OceanGate tweeted last week: “Without any cell towers in the middle of the ocean, we are relying on @Starlink to provide the communications we require throughout this year’s 2023 Titanic expedition.”

It has a 96-hour bottled oxygen supply, as of roughly 6am Sunday local time, according to David Concannon, an adviser to trip operator OceanGate, which would in theory last until Thursday morning . However, that limit would be affected by the breathing rate of those inside the craft, especially if there are tourists onboard with limited diving experience.

What might have gone wrong?

It is too early to say what has happened but experts have offered several of the most likely scenarios, from becoming tangled in wreckage of the Titanic, to a power failure or an issue with the sub’s communications system.

The wreckage of the Titanic, which lies about 3,800 metres (12,500ft) down on the ocean floor is surrounded by debris from the disaster more than a century ago. “There are parts of it all over the place. It’s dangerous,” said Frank Owen OAM, a retired Royal Australian Navy official and submarine escape and rescue project director.

Contact was lost 1 hour 45 minutes into the Titan’s trip, suggesting the crew may have been close to, or at, the bottom, says Owen. The Titan has a maximum speed of three knots, but would be slower the deeper it goes.

In the case of becoming tangled, or a power or communications failure, the Titan would be equipped with drop weights, which can be released in an emergency, creating enough buoyancy to take it to the surface. The Titan has an array of signals, lighting, reflectors and other equipment it can use once on the surface to attract attention.

Another scenario is that there has been a leak in the pressure hull, in which case the prognosis is not good, said Alistair Greig, a professor of marine engineering at University College London.

“If it has gone down to the seabed and can’t get back up under its own power, options are very limited,” Greig said. “While the submersible might still be intact, if it is beyond the continental shelf, there are very few vessels that can get that deep, and certainly not divers.”

Chris Parry, a retired rear admiral with the British Royal Navy, told Sky News a seabed rescue was “a very difficult operation”.

“The actual nature of the seabed is very undulating. Titanic herself lies in a trench. There’s lots of debris around. So trying to differentiate with sonar in particular and trying to target the area you want to search in with another submersible is going to be very difficult indeed.”

What can be done to find it?

US and Canadian aircraft are searching the area, as well as large ships, but the hunt was “complex” because crews do not know if the vessel has surfaced, meaning they must scour both the surface and the ocean depths, said Rear Admiral John Mauger, first district commander of the US Coast Guard, overseeing the search-and-rescue operation.

Concannon said officials were working to get a remotely operated vehicle (ROV) that can reach a depth of 6,000 metres (about 20,000ft) to the site as soon as possible.

These ROVs are dropped over the side of a vessel, to which it is connected by a “umbilical cord” that enables a pilot to operate its thrusters and also relay data in real-time from its sonar and camera systems.

However, the amount of wreckage of the Titanic on the ocean floor means it could take time to discern what is debris and what is the Titan. The search teams do at least have a starting point; the vessel’s position would have been tracked until the moment contact was lost.

The company’s managing director, Mark Butler, told the AP: “There is still plenty of time to facilitate a rescue mission, there is equipment on board for survival in this event,” Butler said. “We’re all hoping and praying he comes back safe and sound.”