MH370 news: How underwater sound recording could reveal 'ALTERNATIVE flight route’

MH370, which was travelling from Kuala Lumpur to Beijing, China, on March 8, 2014, mysteriously vanished with 239 people onboard. Captain Zaharie Shah was in control of the plane when it last communicated with air traffic control at 1:19am over the South China Sea. However, moments later, the plane vanished from civilian radar following a routine handover from Malaysian to Vietnamese channels.

On March 9, 2014, the Chief General of the Royal Malaysian Air Force announced that Malaysia was analysing military radar recordings and that there was a “possibility”that the plane had turned around and travelled over the Andaman Sea.

However, at a press conference on March 15 that year, former Malaysian Prime Minister Najib Razak revealed satellite data from UK company Inmarsat had identified a new route that placed the aircraft anywhere from Kazakhstan to the southern Indian Ocean.

Now though, there may be a third alternative flight path, following suggestions from a mathematics professor at Cardiff University.

Usama Kadri used underwater acoustic waves picked up by a hydrophone – or underwater microphone – placed in the Indian Ocean. 

When acoustic-gravity waves start travelling through the sea floor their propagation speed boosts to over 3,500 m/s, from the 1,500m/s they would have been travelling at through the water.

Previous analysis considered the sea floor to be rigid, which would not allow the radiating waves to move through it. 

However, if the elasticity of the sea floor is taken into account then the waves will travel at this enhanced speed.

Dr Kadri said in January 2019: “When you drop a pebble in a lake, water waves are generated from the location of the impact, while sound waves create the splashing noise you hear. 

“Another type of wave is generated inside the water too – hydroacoustic. 

“Similar to a sound wave, hydroacoustic waves move much faster through the denser water than they would through the air – 1,500 metres per second.

“Similarly, when a large object, such as a meteorite or plane, impacts violently at the surface of an ocean, it generates large surface waves and a family of sound waves that come from a sudden change in pressure known as acoustic-gravity waves. 

“These can travel thousands of kilometres through the water, carrying vital information on the source of the impact, before dissipating.”

Dr Kadri’s study used readings from two hydroacoustic stations locations – the first dubbed HA01, near Cape Leeuwin, Western Australia, while the second, known as HA08s, is at Diego Garcia – an island in the Indian Ocean. 

He added: “Previous studies have mostly looked at the signals collected by station HA01, as well as signals that related to the last satellite data transmission from MH370. 

“However, with our new understanding of acoustic-gravity waves, we decided to look at hydroacoustic data from HA01 that was recorded during a wider time frame and analysed data from the further away HA08s station too.

“Allowing for the effects of sea floor elasticity, the signal locations that we had previously identified using data from HA01 were now different.”

While the Cape Leeuwin recordings (HA01) were relatively clear, those from Diego Garcia (HA08) had been distorted by the noise of a nearby military exercise. 

This made extracting sound potentially related to MH370 from the recorded data much more difficult.

Despite this, Dr Kadri says aligning what they had of HA08 with the recorded data from HA01 produced a new possible impact point.

He continued: “Although the proposed route and point of impact is distant from the 7th arc, we still recommend further studying a number of signals from HA08.

“The bearings of some of these signals fall within the area where signals from the military action were picked up, so it is possible that the signals are associated with the military action.”

If the signals are related to MH370, this would suggest a new possible flight route, leading to an impact location in the northern part of the Indian Ocean.

source: express.co.uk