Searchers can’t yet say whether popping noises are clues to a missing ship
Underwater crashing noises, detected on Tuesday and again on Wednesday, could be an intriguing clue to Sunday’s submarine disappearance near the Titanic wreck — or they could just be unrelated noise. Searchers don’t yet know which one.
Carl Hartsfield of the Woods Hole Oceanographic Institution, who attended a Coast Guard press conference on Wednesday, said the sounds have been described as a “bang” — but said sound is “very complex in the ocean” and experts were still working on it. analyzing the data.
The sounds were detected by a sonobuoy, a floating device equipped with hydrophones to pick up sound underwater, and they seemed to occur every 30 minutes. according to a report in Rolling Stone. That raised the possibility that someone in the ship gave an “impromptu signal to locate the vehicle by banging on the metal part of the hull from the inside,” said Jeff Eggers, a retired Navy commander with experience piloting compact submarines.
“There are a lot of things in the ocean that make noises that can be heard on a sonobuoy, but very few things sound like plain banging on metal,” said Mr Eggers.
Limited information has been released to the public about the ringing sounds, making it difficult for outsiders to guess what might be causing it.
What the sounds might mean “depends largely on what frequency, rhythm and pattern” the sounds have, said Simone Baumann-Pickering, an acoustic ecologist at the University of California San Diego. For example, lower frequency sounds may be made by whales, while higher frequency whistles or echolocation clicks may come from dolphins.
The regularity of the sounds also matters, she said, because natural sound sources such as animals or seismic and volcanic activity tend to generate sounds that are more variable than man-made sounds.
“I think it would be quite easy to determine whether something is a ground signal or a biological signal or a machine signal,” said Dr. Baumann Pickering.
Search and rescue teams flying the aircraft deploying the sonobuoys are experts at distinguishing faint sound signatures from submarines from other sources of underwater noise, Mr Eggers said. But to track down the precise origin of the popping noises, he said, teams will need to expand monitoring in the area with more sonobuoys. “Every bit of data and positional information helps,” he said.
Mr. Hartsfield, a laboratory director at the Woods Hole Oceanographic Institute, spoke about the challenges.
“From my experience with acoustics, there are biologic sounds that sound man-made to the untrained ear,” he said. “But I can assure you that the people listening to these tapes are trained.”