Experts are searching for a missing submersible in the area where noises have been heard beneath the surface, the US Coast Guard confirmed.
Captain Jamie Frederick told reporters in Boston on Wednesday the cause of the noises in the North Atlantic was still unconfirmed but insisted the efforts to find the five missing people aboard the Titan was still “a rescue mission”.
The vessel lost communication with tour operators on Sunday while about 435 miles south of St John’s, Newfoundland, during a voyage to the Titanic shipwreck off the coast of Canada.
The 6.7m (22ft)-long OceanGate Expeditions vessel, which has British billionaire adventurer Hamish Harding on board, may have less than 20 hours of oxygen left.
Also in the undersea craft are UK-based businessman Shahzada Dawood, his son Suleman Dawood, and OceanGate’s chief executive and founder Stockton Rush, reportedly with French submersible pilot Paul-Henri Nargeolet.
Speaking at a press conference, Capt Frederick said the size of the area being investigated was “roughly two times the size” of US state Connecticut. The state is around 5,000 square miles.
He added: “The good news is we are searching in the area where the noises were detected.”
On Titan’s dwindling oxygen levels, he said: “Oxygen is just one piece of data. There are lots of pieces of data that we need to study. But (oxygen) is not the only thing that’s important.”
The vessel reportedly had a 96-hour oxygen supply in case of emergencies.
Asked if they were still treating the passengers as alive, he added: “This is a search and rescue mission, no doubt about it”.
The US Coast Guard announced earlier on Wednesday that Canadian P-3 aircraft had detected underwater noises.
The sounds were detected on Tuesday and then again on Wednesday but searchers “don’t know what they are,” Capt Frederick said.
He said: “Yesterday a Canadian P3 detected underwater noises in the search area.
“As a result ROV (remotely operated vehicle) operations were relocated in an attempt to explore the origin of the noises. Although the ROV searches have wielded negative results, they continue.
“The surface search is now approximately two times the size of Connecticut, and the sub-surface search is up to 2.5 miles deep, exponentially expanding the size of the search area.
“With the respect to the noises specifically, we don’t know what they are, to be frank with you, they’re P3 detected noises, that’s why they’re up there, that’s why they’re doing what they’re doing, that’s why they put sonar buoys in the water.”
He said “we’re searching in the area where the noises were detected, and we’ll continue to do so”, adding that additional “ROVs will be there in the morning” to help.
Carl Hartsfield, from the Woods Hole Oceanographic Institution, told reporters that the the noises are being analysed by “the best people in the world”.
He added: “The ocean is a very complex place, obviously human sounds, nature sounds, and it’s very difficult to discern what the sources of those noises are at times, but I can tell you that this team has multiple sensors that are in the area, they’re sending data back expeditiously to the best people in the world to analyse that data and they’re feeding the results of the analysis back to the unified team and they’re making decisions.
“There have been multiple reports of noises and every one of those noises is being analysed, tracked, looked for patterns and reported upon.”
Mr Hartsfield added that the noises have been described as “banging noises”.
Other potential man-made sources of the noises have to be eliminated, reporters were told.
Asked if it was possible a ship in the ocean or some mammals could mimic the sound, Mr Hartsfield said: “I can tell you from my experience with acoustics, that there are sounds, biologics that sound man-made to the untrained ear, but I can assure you that the people listening to these tapes are trained.
“There are a lot of vessels in the area and they each make noise, so all of that has to be eliminated and it’s analysis over time, plus the team is searching in the right area, so if you continue to do the analysis, look for different patterns and search in he right area, you’re doing the best you can possibly do with the best people on the case.”
An object spotted in the ocean by an aircraft during the search for Titan is not believed to be debris, Capt Frederick said.
In a statement on their website, deep water specialists Magellan said they were contacted by OceanGate on Monday and “immediately” offered knowledge of the site and expertise in operating at depth.
The company added that it has been working with UK and US agencies to move its specialist equipment and support crew to St John’s, Newfoundland, following instructions to mobilise from OceanGate.
The Ministry of Defence (MoD) also said the UK-based Nato Submarine Rescue System (NSRS) team is available to offer expertise and guidance to the search operation.
But reports indicate the the depths involved in the search “greatly exceed” that which the NSRS can safely operate.
