Malaysia Airlines MH370 latest news: Twelve years after Malaysia Airlines’ MH370 vanished, an overlooked clue is back in focus
The Boeing 777 disappeared on March 8, 2014, after its transponder stopped identifying the plane on civilian radar. However, the plane continued to communicate with the Inmarsat satellite for several hours. According to one report, timing and frequency data from these contacts indicate that MH370 flew south toward the Indian Ocean before ending up near a curved line of possible locations known as the “seventh arc.”
Search teams spent years searching for the wreckage there. They found nothing. This revived interest in another possible source of evidence: underwater sound.
Could hydrophones have detected the crash of MH370?
Hydrophones are underwater microphones that record sounds traveling through the ocean. According to a Popular Mechanics report, researchers believed they may have detected the impact of a large plane crashing into water.
CTBTO’s global hydroacoustic network became the initial focus. Their hydrophones can record sounds over very long distances, and there was already evidence that such data could help locate objects under the sea.
In 2017, CTBTO stations detected an unusual underwater signal near the last known location of Argentina’s missing submarine, the ARA San Juan. The wreckage was found the following year.
A large plane crashing into the ocean would also have created an acoustic signal. A 2024 study by Cardiff University researcher Usama Kadri found that sound from previous plane crashes at sea traveled 2,000 to 5,000 kilometers through water, Popular Mechanics reports. However, researchers examining CTBTO data did not find a convincing signal near the presumed impact site of MH370 along the seventh arc.
Instead, a low-frequency signal recorded west of Rottnest Island appeared to point northwest, near the Chagos-Laccadive Ridge.
The simplest explanation was an underwater earthquake or another natural event. But one researcher believes it could be something much more important.
An overlooked hydrophone network recorded the Indian Ocean
French researcher Royer’s OHASISBIO network had been recording low-frequency sounds in the southern Indian Ocean since 2010, Popular Mechanics reports.
The instruments were not designed to search for missing aircraft. They were built to study small earthquakes and seafloor spreading while also recording whale calls.
Unlike the CTBTO network, the hydrophones stored recordings internally and had to be recovered before the data could be analyzed.
MH370 disappeared just a few weeks after the instruments were deployed.
When the network was recovered in early 2015, one of the hydrophones closest to the presumed crash site of MH370 was lost. However, the remaining tools survived.
Royer later identified five possible acoustic events around the time MH370 disappeared. Two had already been identified in previous CTBTO-based studies.
He sent his analysis to French and Australian authorities in late 2016 but it was not included in the ATSB’s final investigative report published the following year.
Royer believes officials may have interpreted the study as too similar to previous CTBTO analyses, according to the Popular Mechanics report. Yet independent recordings showed that different hydrophone networks detected some of the same events.
Could MH370 have crashed somewhere else?
Acoustic evidence does not invalidate satellite analysis. But it adds to the growing list of questions surrounding the official search field.
The MH370 wreckage confirmed that parts of the plane had reached the western Indian Ocean, but drift models struggled to explain the journey of each piece. Meanwhile, years of seabed searches have found no wreckage.
Between 2014 and 2017, Australian-led searches covered more than 120,000 square kilometers of seabed. Ocean Infinity’s 2018 survey brought the total area searched to close to 200,000 square kilometers.
As of March 2026, the company said it had mapped more than 140,000 square kilometers of seafloor since returning to the search but had still not found the plane.
“If nothing else, we can say with confidence that it’s not where we’re looking,” Ocean Infinity CEO Oliver Plunkett said, as quoted by Popular Mechanics.
David Dall’Osto, senior research scientist working on CTBTO hydroacoustic data, believes the unexplained signal in the northwestern Indian Ocean may be the acoustic signature of MH370’s impact.
If he’s right, the 12-year search may have been focused in the wrong place. “There was a sound right there,” Dall’Osto said, as quoted by Popular Mechanics.
