Underwater vehicles redeployed in response to ‘banging noises’ with 32 hours of oxygen left on Titanic sub

Underwater vehicles which are being used in the search for the missing submersible containing five people that vanished near the wreck of the Titanic have been redeployed after 'banging noises' were picked up.

OceanGate's Titan submersible has been the subject of a 'complex' search process after the small vessel went missing under the sea on Sunday (18 June).

On board are five passengers: British billionaire Hamish Harding; French maritime expert Paul-Henri Nargeolet; Shahzada Dawood and his son Sulaiman; and OceanGate CEO Stockton Rush.

US and Canadian coast guards have put a great deal of effort into the search for the submarine but as of yet, they've not been successful in finding it.

Time is of the essence as the submersible has a limited supply of oxygen and it is expected to run out tomorrow (22 June).

While the submarine hasn't been found there have been potential clues which the search and rescue operations are investigating.

The US coast guard recently confirmed that a Canadian P-3 aircraft detected 'underwater noises in the search area' and two search crews have picked up 'banging noises' not far from where the submersible went missing.

A government memo from the Department of Homeland Security said sonar had been detecting regular banging noises every 30 minutes and could still be heard at regular intervals hours later.

Remote underwater vehicles were redeployed in response to the banging noises and while they have not yet found anything the search efforts continue.

It is hoped that the regular banging noises are the submarine's passengers sending out a distress message to be picked up by sonar detection tools.

Conditions inside the sub are likely to be cramped and claustrophobic, with five people inside the 22 feet long and nine feet wide vessel.

If the submarine and the five people aboard are found safe and sound then they will still need help to get out of their current predicament.

A former passenger of the OceanGate Titan submersible said the crew inside had no way of getting out by themselves as the hatch is sealed from the outside with 17 bolts.

CBS reporter David Pogue said the sub had seven ways to rise to the surface and it was worrying that none of them had been used.

Last year Shrenik Baldota was on board the Titan as a passenger and said they'd been 'lost for two-and-a-half hours' beneath the sea during his journey.

The submarine does not use GPS, it is instead guided by text messages using an ultra short baseline (USBL) system.