More banging noises heard in search for missing Titanic-bound submarine

BOSTON – Rescue crews in the Atlantic Ocean detected potential signs of life again on Wednesday as they continue searching for a submersible that went missing during an expedition to the site of the Titanic wreckage.

According to the U.S. Coast Guard, a Canadian P-3 aircraft detected underwater noises in the search area on Tuesday. Because of those noises, the operations were relocated "in an attempt to explore the origin of the noises."

Coast Guard Capt. Jamie Frederick said in a Wednesday afternoon news conference that the sounds "have been described as banging noises." He said the P-3 also detected noises on Wednesday.

"We don't know what they are, to be frank with you," Frederick said. "We're searching in the area where the noises were detected."

The search area has now expanded to two times the size of Connecticut. Two remotely operated underwater vehicles are "actively" searching below the surface and more are on the way.

The submersible had as much as 96 hours of oxygen when it began the expedition on Sunday morning, as well as limited food and water rations, Frederick said.

"This is a search and rescue mission, 100%" he said. "We need to have hope."

Read: If the missing Titanic sub is found, what's next for the rescue effort?

The Coast Guard tweeted that three vessels arrived Wednesday morning. The John Cabot has side-scanning sonar capabilities and is searching alongside the Skandi Vinland and the Atlantic Merlin.

The 21-foot Titan vessel submerged Sunday morning around 8 a.m. and was expected to resurface at 3 p.m. that day. The crew of the Canadian research vessel Polar Prince lost contact with the submersible about 1 hour and 45 minutes into the dive, the Coast Guard said.

OceanGate Expeditions, a company that deploys manned submersibles for deep-sea expeditions, operates the missing vessel. The company did not say whether any of the people on board are paying tourists. It takes them as passengers on its expeditions.

The wreckage of the Titanic is about 13,000 feet under the surface.

Among the confirmed passengers are British businessman Hamish Harding; Pakistani businessman Shahzada Dawood and his teenage son, Suleman; and French explorer Paul-Henri Nargeolet. Stockton Rush, the CEO of OceanGate, the company that operates the vessel, is also on it., a British billionaire and adventure traveler, is among the group of those missing.