A team of Australian researchers recorded an unusual acoustic event around the time Malaysia Airlines flight MH370 would have crashed owing to fuel exhaustion.
The signal was detected by underwater acoustic sensors 40km off Australia’s Rottnest Island at 01:30 GMT on Saturday 8 March.
“[The signal] could have resulted from Flight MH370 crashing into the Indian Ocean but could also have originated from a natural event, such as a small earth tremor,” says a statement from Curtin University’s Centre for Marine Science and Technology.
They add that researchers from the United Nations Comprehensive Nuclear-Test-Ban Treaty Organisation (CTBTO) and Geoscience Australia have also been involved in the analysis of the data.
Using the data from two sets of widely separated underwater sensors, the team was able to triangulate the source and distance of the sound. They caution, however, that this gives a location that “is not compatible with the satellite ‘handshake’ data transmitted from the aircraft, which is currently considered the most reliable source of information.”
A search for the lost Boeing 777-200ER aircraft commenced off the west coast of Australia after analysis of satellite data from satellite firm Inmarsat showed several ‘handshakes’ on 8 March. The last of these came at 00:18:37 GMT on Saturday 8 March.
“Soon after the aircraft disappeared, scientists at CTBTO analysed data from their underwater listening stations south-west of Cape Leeuwin and in the northern Indian Ocean,” says Curtin’s Alec Duncan. “They did not turn up anything of interest.”
When the search moved to the southern Indian Ocean, however, the team recovered recorders located west of Rottnest Island. Rottnest Island is 10km due west of Perth. Cape Leeuwin is located several hundred kilometres to the south of the city.
Data from one of the recorders “showed a clear acoustic signal at a time that was reasonably consistent with other information relating to the disappearance of MH370. The crash of a large aircraft in the ocean would be a high energy event and expected to generate intense underwater sounds.”
This prompted the team to re-examine the original Cape Leeuwin data.
“A very careful re-check of data from that station showed a signal, almost buried in the background noise but consistent with what was recorded on the IMOS recorder off Rottnest,” says Duncan.
Duncan adds that the team will continue to work with search authorities, and that it has other recorders around the Indian Ocean that might yield data related to MH370.
MH370 disappeared with 227 passengers and 12 crew. Despite months of searching in the Indian Ocean, no trace has been found of the missing aircraft.