Missing Titanic submersible: Is new deep-sea rescue equipment the crew's last chance at survival?
"Banging sounds" were detected underwater in the search for the missing submersible, taking tourists to see the Titanic shipwreck, ITV News Reporter Charlie Frost has the latest
Vital pieces of deep-sea rescue equipment have arrived on three US cargo planes in the search for the missing Titanic submersible.
Five crew members, including a British billionaire and a British-Pakistani father and son, are aboard the vessel, named Titan, currently missing after the sub was reported overdue on Sunday.
A large-scale search and rescue operation has been combing thousands of square miles of ocean, but the allotted oxygen supply set to run out on Thursday around 10am BST makes it a race against time.
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What has the search and rescue operation looked like so far?
The US coastguard and Canadian authorities have been focusing on locating the vessel - and have not yet addressed what retrieving it would look like - but confirmed more than 10,000 square miles of ocean have been searched.
A spokesperson said on Tuesday if Titan was bobbing about the sea's surface, they would be able to find it.
But as they have extended their search into deeper waters, it seems the possibility the sub is still in the depths of the ocean is becoming the most likely, and sonar technology has picked up "banging sounds" from underneath the water, according to an internal US government memo early on Wednesday.
With no direct communication options available, sonar is the best chance at finding an approximate location of the vessel and crew.
A fleet of ships, military planes, and crews have been working around the clock to scan the waters 900 miles off the coast of Cape Cod, as a Canadian P-3 aircraft was said to also have located a white rectangular object in the water.
However, another ship set to investigate was diverted to help research the acoustic feedback instead.
The issue agreed upon by all the experts, is reaching the sub.
If it is near the Titanic shipwreck, it will be nearly 12,000ft underwater.
Equipment capable of reaching those depths has not been at hand - until now.
The machinery capable of reaching Titan
Early on Wednesday, it was reported that a remotely-operated vehicle (ROV) had been flown into Canada from the US.
It is no ordinary ROV, however, but one that can go 19,000ft deep underwater.
Three C-17 aircraft from the US Air Force - which are believed to have flown in from North Carolina and New Jersey - landed at a cargo terminal in St. John's, Newfoundland, where they were met by six waiting trucks, according to multiple reports.
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One load contained two heavy-duty Hyundai winches with "6000kg line pull" written on the side.
And one crate reportedly named the Massachusetts-based company, Pelagic Research Services (PRS), who specialise in deep-sea rescue equipment.
One of their services includes an ROV called the Odysseus 6K, that is capable of reaching 6,000 metres (nearly 20,000ft) underwater.
A statement on the PRS website read: "PRS has been contacted by OceanGate Expeditions to provide critical support in the current rescue operation of the submersible Titan in the North Atlantic.
"Currently, PRS is in the process of mobilization as quickly and as safely as possible to assist in the search and rescue effort... PRS is committed to helping bring the best possible outcome to this situation.
"Our sincere thoughts, hopes, and prayers are with all the families, friends, and rescue personnel of those affected by this emergency."
The machinery was loaded off planes and onto trucks, before being transported with a police escort.
What are the chances of survival with the Odysseus 6K?
The ROV can reach the vessel, but whether it can play any part in retrieving it remains unclear.
Titan weighs 10,432kg, which means both winches would need to be used to pull it up from the sea bed - if it is possible.
Some reports have suggested by the time the ROV is ready to be deployed, it will have just 15 hours before the crew's oxygen supply is up.
For this reason, the equipment is being considered Titan's last chance for rescue.
Even if the search and rescue teams are able to locate the vessel and pull it to the surface in time, they will then have to race to unbolt the door before the crew suffocates, as it can only be opened from the outside.
At this moment in time, and with little hours remaining on the clock, authorities will want to get the machinery in the water as quickly as possible.
If they are unable to, the chances at survival are low.
What have experts and colleagues of the crew said?
Analysis of the situation has varied - some remain hopeful and others are not.
Chris Parry, a retired navy rear admiral from the UK, said without an “emitting signal” from the missing deep-sea vessel will be “impossible” to find in the timescale.
He told LBC: “I’m afraid the odds are vanishingly small.
“Obviously, we want to remain hopeful and optimistic but there are two problems here – one is actually finding the thing and secondly is how on earth are you going to get it off the seabed.
"It’s never been done before and I don’t think anybody’s got any ideas about how to do it at the moment."
Dik Barton, the first British diver to see the Titanic wreck, said it is a “dangerous” and “hostile” place to be.
Mr Barton told the programme he is friends with Paul-Henry Nargeolet, reported to be on board the missing vessel, and referred to him as “PH”.
“I’ve worked with him extensively, I have enormous respect for him and his ability, and, quite frankly, if there’s anybody I’d ever want to be in a position, God forbid, in this circumstance then it would be PH."
But Mr Barton added there is no way of accessing the submersible on the sea bed and that for passengers and crew to be rescued the vessel has to be recovered back to the surface.
However, a businessman who has made the deep-sea voyage to the wreck of the Titanic has expressed confidence in the Titan crew and said “there’s a very good chance they will be found”.
Oisin Fanning told BBC Radio 4’s Today programme he had been on the submersible with pilot Mr Nargeolet and OceanGate CEO Mr Stockton Rush.
"The two guys on the sub currently, so Paul and Stockton, are both consummate professionals," he said.
"I mean, to be honest, if I was in trouble, I’d want to be on a sub with them."
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