Drifting trajectory analysis of debris from MH370 in the southern Indian Ocean

Malaysian Airlines Flight 370 disappeared on 8 March 2014, while flying from Kuala Lumpur, Malaysia, to Beijing, China. A piece of marine debris, later confirmed to be a flaperon from Flight 370 by the French prosecutor, was found on Réunion Island in the western Indian Ocean on 29 July, 2015. The aircraft debris are assumed to drift in the surface layer and the vertical movement is not taken into account in the present study. Based on the surface drifting buoys and maritime objects drift prediction model, the drifting trajectories and time scales of the debris are estimated. It was found that eleven surface drift buoys passed in the possible air crash waters that finally reached Réunion according to analysis of surface drift buoys in Indian Ocean. Among these, two buoys cost about 500 days, which was close to the debris drift time, testified the possibility that debris from the possible air crash waters could drift to Réunion, from the point of observational facts. Based on Leeway maritime drift theory, the Leeway factors were reparameterized, the wave effect was ignored, the reanalysis of currents and winds in southern Indian Ocean was processed as forcing field, a maritime object drift prediction model for the southern Indian Ocean was established. Three experiments with different Leeway factors were carried out to compute the drift trajectory of the objects initially deployed in the possible air crash waters for 500 days. The results show that the trajectories of the objects are basically the same with the surface drift buoys, indicating the dependable performance of the drift prediction model. The final position of most objects are in 10°~35°S. The probability of objects arrive Réunion Island area for different leeway factors as 1.2%, 1.5%, 1.8% is 7%o, 13%o, and 28%o. The probability increases along with the leeway factor because the wind is mainly southeast trade wind in the drift area. Due to the long integration time, position difference of every time step accumulates, eventually causes the far distance of different leeway factors. Three kinds of trajectory are concluded for the objects in Réunion Island area at the end of the prediction.