Malaysian Flight MH370: How British Firm Inmarsat Used 19th Century Mathematical Model of ‘Doppler Effect’ to Track Plane
By Gopi Chandra Kharel | March 25, 2014 7:58 PM EST
Malaysian authorities gave some sort of finality to the case of the missing plane MH370 on Monday, in a chilling late night announcement by Prime Minister Najib Razak and a bold SMS to the family members of the passengers onboard.
British firm Inmarsat used the 19th century mathematical model of 'Doppler Effect' to track MH370's position. (Representational Picture: Reuters)
PM Razak said in a news conference, citing data and satellite analysis from a British company called Inmarsat, that MH370's journey "ended in the southern Indian Ocean". He said that the last known position of the missing plane was in the middle of the Indian Ocean. Razak expressed "deep sadness and regret" while informing the news to the family members.
"It is with deep sadness and regret, that according to this new data, flight MH370 ended in the southern Indian Ocean," Razak said.
Meanwhile, an SMS sent to the relatives, and was widely criticized later, read: "Malaysia airlines deeply regrets that we have to assume beyond any reasonable doubt that MH370 has been lost and that none of those on board survived".
The bold statement has been slammed for the lack of clear evidence, and questions are being asked on how the Malaysian authorities have reached the conclusion in the first place.
Scientists from UK satellite firm Inmarsat are understood to have used the 19th century mathematical model of the 'Doppler effect' (or Doppler shift) to track the fate of MH370.
The Doppler effect, named after Austrian physicist Christian Doppler who proposed it in 1892 in Prague, is the change in the frequency of a wave of an observer moving relative to its source. One common example used to describe this theory is what we hear when a vehicle sounding a siren or horn approaches, passes and recedes from an observer.
So how was this model used to analyze the possible location of the MH370?
First, even if the rest of its communications systems had stopped working, Radar pings from the ill-fated flight were automatically transmitted every hour from the aircraft. This indicated that the plane continued flying for hours after it disappeared from the civilian radar an hour into its journey from Kuala Lumpur to Beijing.
Analyzing the time it took for the signals to reach the satellite belonging to Inmarsat, and the angle of elevation, the British firm was able to provide two arcs, one that extended towards the north and the other to south - signifying the path that the aircraft could have taken.
Scientists then interrogated the pings using the Doppler effect. The observer in this case was the satellite, and scientists analyzed how the wave of the ping changed frequency relative to the movement of the satellite.
Razak said during the press conference on Monday that Inmarsat employed "a type of analysis never before used in an investigation of this sort".
Speaking to the BBC, Inmarsat's senior vice president Christ McLaughlin explained how his firm was able to conclude that the plane definitely few south.
"We took Malaysian 777 airline data and modeled that against the northern and southern path and what we discovered was that the path to the south is undoubtedly the one taken."
The data revealed definitively that MH370 flew along the southern corridor based on the pings.
The Malaysian authorities confirmed, citing the data, that the last known position of the plane was in the middle of the Southern Indian Ocean. And since there is no place to land safely anywhere near the spot, it has to be rationally concluded "beyond reasonable doubt" that the plane "ended in the Southern Indian Ocean" and "none of those on board survived".
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