Missing Titanic tourist vessel: Difference between a submersible and a submarine

NEW YORK - The Titan, the

vessel that went missing in the area of the Titanic wreck

in the North Atlantic on Monday, is classified as a submersible, not a submarine, because it does not function as an autonomous craft, instead relying on a support platform to deploy and return.

According to the website for the tourism company operating the Titan, OceanGate Expeditions of Everett, Washington, the missing vessel is a submersible capable of taking five people – one pilot and four crew members.

It can travel to depths of 4,000m for “site survey and inspection, research and data collection, film and media production, and deep sea testing of hardware and software”.

Made of titanium and carbon fibre, it weighs about 10,432kg and is listed as measuring 6.7m by 2.8m by 2.5m, with 96 hours of “life support” for five people.

The Titan, one of three types of crewed submersibles operated by OceanGate, is equipped with a platform similar to the dry dock of a ship that launches and recovers the vessel, the website said.

“The platform is used to launch and recover manned submersibles by flooding its flotation tanks with water for a controlled descent to a depth of 9.1m to avoid any surface turbulence,” according to the website.

“Once submerged, the platform uses a patented motion-dampening flotation system to remain coupled to the surface yet still provide a stable underwater platform from which our manned submersibles lift off of and return to after each dive,” the site continues.

“At the conclusion of each dive, the sub lands on the submerged platform and the entire system is brought to the surface in approximately two minutes by filling the ballast tanks with air.”

OceanGate calls the Titan the only crewed submersible in the world that can take five people as deep as 4,000m enabling it to reach almost 50 per cent of the world’s oceans.

Unlike other submersibles, the Titan, the website said, employs a system that can analyse how pressure changes affect the vessel as it dives deeper, providing “early warning detection for the pilot with enough time to arrest the descent and safely return to surface”.

The Titan began deep-sea ventures related to the Titanic in 2021.

According to the tech news site GeekWire, the vessel was “rebuilt” after OceanGate determined through testing that the vessel could not withstand the pressure of a 4,000m dive. NYTIMES