Malaysia Airlines Flight 370 (2014): A report without a cause

Inmarsat’s ground station kept receiving automated handshakes from the aircraft’s satellite data unit for hours after the last voice call. Burst-frequency-offset analysis, later reviewed by the ATSB and by an international working group, produced the southern-arc end-of-flight estimate that moved the search from the South China Sea to the southern Indian Ocean. The method is technical and public; it is not a photograph of the seabed.

Surface and underwater searches ran first in the South China Sea and the Strait of Malacca, then, after the 24 March announcement, in a vast box west of Australia. The ATSB-led seabed survey covered about 120,000 square kilometres. It found no 777. A 2018 Malaysian safety report recorded the known facts, the debris identifications and the absence of a cause. It did not name a perpetrator and did not close the wreck-file.

The Réunion flaperon, confirmed by French judicial authorities in September 2015, and later pieces examined in Australia and elsewhere, proved that at least part of 9M-MRO reached the western Indian Ocean. Drift studies then tried to back-calculate a crash latitude. Those studies narrowed arguments; they did not replace a locator beacon or a wreck photograph.