Take a look at the conditions inside the extremely cramped sub vessel that went missing on a Titanic wreckage dive.

A massive operation was launched on Sunday (18 June) after the missing submersible vanished about 435 miles (700km) south of Newfoundland, Canada.

The tiny craft operated by OceanGate Expeditions, named the Titan, carries five people on board with authorities nowracing against time to locate them.

OceanGate

The craft lost contact with its surface crew on Sunday as it explored the underwater gravesite of the Titanic wreckage which lies around 12,500ft deep - 370 nautical miles.

Titan's inside space is just 22ft long and 9ft wide with a height of a little over 8ft.

The small space has capacity for five people, including a pilot and a ‘content expert’ as well as three paying customers.

One of those paying customers is British billionaire Hamish Harding, according to his stepson.

Taking to Facebook, his stepson confirmed that he was missing: "Thoughts and prayers for my Mom and Hamish Harding.

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"Hamish Harding my stepfather has gone missing on submarine thoughts and prayers."

Joining Harding on the trip were UK-based father and son, Shahzada Dawood, 48, Sulaiman Dawood, 19, according to their family.

The family said: "Our son Shahzada Dawood and his son, Suleman, had embarked on a journey to visit the remnants of the Titanic in the Atlantic Ocean.

"As of now, contact has been lost with their submersible craft and there is limited information available."

CEO of OceanGate Expeditions, Stockton Rush, which operates the vessel, is also on board the missing sub.

Rush showed prospective customers a tour of Titan last year - revealing the extremely claustrophobic conditions inside.

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During the tour, he said: "We are inside the submersible, Titan, which is a carbon fibre and titanium sub that can go to the depths of the Titanic."

He then showed a small hole located in the base of the sub next to the craft's only window, explaining: "This is the only toilet available on the deep-diving submersible.

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"Best seat in the house, you can look out the viewport, we put a privacy screen in, turn up the music and it’s very popular."

The CEO added: "We have our control screen, our sonar screen and we can put any image we want in the back."

Rush went on to outline how exactly the craft is controlled - namely with something likened to a 'game controller'.

Titan is driven by a Logitech game controller and touch screens, with Rush informing: "We’ve taken a completely new approach to the sub design and it’s all run with this game controller and these touch screens.

"It’s bluetooth so I can hand it to anybody and it’s meant for a 16-year-old to throw it around and super durable. We keep a couple of spares on board just in case."