Since March 8, 2014 when Malaysia Airlines' Boeing 777 with the number MH370 disappeared without a trace along with 239 people, the world has yet to explain what really happened.
Amidst countless hypotheses, lackluster data lines and still smiling pain, there is one detail that still makes people scary: 5 last words from the cockpit.
Goodnight Malaysia three seven zero - the last farewell of MH370 captain Zaharie Ahmad Shah to the air traffic control station before the plane left Malaysia. After that, the plane suddenly "disappeared" from radar, did not send any more signals, did not leave a distress call, and did not receive a response from the flight crew.
That seemingly normal moment - a greeting in the air traffic route - is now one of the coldest mysteries in the history of modern aviation.
Although it no longer broadcasts conventional signals such as ADS-B, secondary radar or ACARS, MH370 still leaves a " footprint" in the sky through Inmarsat satellite signals and data from the WSPR system - a tool that few people expect recorded by global radio amateur.
Professor Simon Maskell (University of Liverpool, UK) and his international research team used data from WSPR to recreate MH370's journey, thereby eliminating many unreasonable theories, including speculation about being shot down or kidnapped.
Maskell's analysis shows three likely scenarios:
The sudden accident left the crew unable to control or communicate.
A murder - suicide, in which the perpetrator survived the crash.
A murder - suicide, but the perpetrator died before the fall.
The premise of a carefully calculated suicide case became more serious after Malaysian authorities discovered a simulated secret flight path in a computer at the home of captain Zaharie, which fears a match to the trajectory where MH370 is estimated to have flown towards the Indian Ocean.
However, there is no evidence to conclude that Zaharie or his deputy caused the incident. Only one truth is confirmed: the plane did not crash freely due to pure technical errors. The complete "silence" of the cockpit and the ability to control purposefully makes the hypothesis of human intervention in the final stage increasingly seen as well-founded.
Although millions of dollars have been poured into the search for MH370 for more than a decade, the plane is still somewhere at the bottom of the ocean as an uncoverted mystery.
"These types of accidents, whether caused by accident or intentional, are extremely rare. But it is certain that this is not a random disappearance, said Professor Maskell.
And until MH370 was found, 5 words from that last resounded like a fateful greeting, concluding the final dialogue between humanity and a plane that never returned.
