Missing Titanic sub rescuers heard noises like 'banging' but haven't found the sounds' source yet

• Multiple planes have detected noises where the Titanic submersible went missing, according to the US Coast Guard.
• They're still searching the area where the sounds were heard, but haven't found the submersible yet.

A Canadian surveillance plane has detected underwater noises in the area where rescuers are searching for a missing tourist submersible, the US Coast Guard confirmed on Tuesday evening, but searchers have yet to find the source.

"Canadian P-3 aircraft detected underwater noises in the search area," the First Coast Guard District tweeted. "As a result, ROV operations were relocated in an attempt to explore the origin of the noises. Those ROV searches have yielded negative results but continue."

At a Wednesday press conference, Captain Jaime Frederick, response coordinator of USCG's First District said more P-3 aircrafts detected noises Wednesday morning and the search and rescue mission continues to explore the area where the noises were detected.

ROVs, or remotely operated vehicles, are unmanned vehicles that can search areas underwater and possibly have the capacity to recover undersea objects.

The Coast Guard's confirmation comes as Rolling Stone reported on Tuesday that searchers on a Canadian aircraft detected "banging" in 30-minute intervals coming from the area where the submersible went missing.

"The P8 heard banging sounds in the area every 30 minutes. Four hours later additional sonar was deployed and banging was still heard," said the email sent by the Department of Homeland Security's National Operations Center, obtained by Rolling Stone.

But the Coast Guard would not confirm whether the noises were in fact "banging" and said they had not heard anything about 30-minute intervals.

Carl Hartsfield from the Woods Hole Oceanographic Institution said at the presser that the noises have been "described as 'banging noises,'" but that "noises are very complex in the ocean."

"You have to be an acoustic analysis and you have to have context," Hartsfield explained. "They're trying to put all the pieces together. They have to eliminate potential manmade sources other than the Titan."

Another Tuesday night internal memo said sonar picked up "additional acoustic feedback" that was "indicating continued hope of survivors," according to CNN.

Richard Garriott de Cayeux, president of the Explorers Club, tweeted on Tuesday evening that the club received information that "likely signs of life have been detected at the site."

He wrote that the club has "much greater confidence" that "there is cause for hope, based on data from the field."

Two of the submersible's passengers, British billionaire Hamish Harding and Paul-Henri Nargeolet of France, are part of the Explorers Club.

The search for the missing submersible entered its third day on Tuesday. The US Coast Guard and Canadian authorities has deployed a submarine, ships, aircraft, and sonar buoys in hopes of finding the vessel.

The submersible, called the Titan, is run by OceanGate Expeditions and was carrying a total of five people to see the Titanic shipwreck at around 13,000 feet under the surface.

It lost contact with its mother ship on Sunday afternoon, after more than an hour into its dive.

Past safety concerns regarding the Titan's hull and its ability to withstand deep-sea pressure have prompted fears that the submersible may have been breached, killing all passengers within.

But there's also the possibility that the Titan is intact, and that all five passengers are still alive. If that is the case, oxygen in the submersible is likely to last until Thursday afternoon ET, per the Coast Guard's estimates.