At first, the search effort for missing Malaysia Airlines Flight MH370 focused mainly on the South China Sea.
But it switched to the Indian Ocean as radar and satellite tracking data fed suspicions that the Boeing 777 was deliberately flown hundreds or possibly thousands of miles off course.
Investigators believe the aircraft’s communication systems were disabled on purpose. An early theory was that it had headed out over the Andaman Islands.
An investigation began into the pilot and co-pilot.
Captain Zaharie Ahmad Shah had a flight simulator and was reportedly politically active. Co-pilot Fariq Abdul Hamid was said to have breached safety rules in the past by letting passengers into the cockpit.
Their homes in Kuala Lumpur were searched and passengers’ backgrounds were also probed. At least two, both Iranians, had used stolen passports but this
was linked to illegal immigration rather than any terrorist motive.
As more countries joined the search, satellite signals indicated the plane may have flown for six hours or more after dropping off Malaysian military radar.
They also placed it within either a corridor
from northern Thailand to the border of Kazakhstan and Turkmenistan, or a southern corridor from Indonesia to the Indian Ocean off Australia.
An increasing number of floating objects are being spotted in the search zone where the flight ‘ended’, in the southern Indian Ocean west of Perth, Australia.
The next challenge is recovering debris and crucially, finding the black box flight recorders.
Time is of the essence as the locator beacons they carry fade out after 30 days.
Flight MH370 vanished less than an hour after take-off.
Search teams know that if the black boxes remain at the bottom of the ocean, the mystery of what happened on March 8 may never be solved.