The search for MH370 and ocean surface drift – Part III
Several high-resolution surveillance satellites were tasked to obtain images of the ocean in the vicinity of the 7th arc while the surface search for missing flight MH370 was underway in March 2014. Many objects of interest were seen in several of these images from a wide range of locations at the time, but none led to any successful recoveries. Four of these images, taken just west of the 7th arc in the vicinity of the new search area proposed by ATSB in 2016, have recently been carefully re-examined (Minchin et al. 2017). Three of these images (referred to as PHR4, PHR3 and PHR1) contained 9, 2 and 1 objects, respectively, that were classified as “probably man-made” as well as 28 “possibly man-made” objects. The dimensions of these objects are comparable with some of the debris items that have washed up on African beaches and their location near the 7th arc makes them impossible to ignore. But there is no evidence to confirm that any of these objects (let alone all) are pieces of 9M-MRO (the aircraft flying as MH370).
To completely reject the possibility that any of these objects are pieces of 9M-MRO is difficult to defend. Consequently, we have addressed the obvious question raised by this new piece of uncertain, but plausibly-relevant evidence:
If at least some objects in the images are pieces of 9M-MRO, from where did they drift in the weeks between the disappearance of the aircraft and image capture?
This question is, perhaps surprisingly, potentially more difficult to answer than the ones we addressed in the two reports preceding this one. This is because it requires a very detailed knowledge of the surface currents out in the middle of the ocean where almost no in-situ observations have ever been made. However, thanks to the combined data sets from several types of Earth-observation satellites, coupled with the computational power of Australia’s most powerful super-computer and more than a decade of Government investment in operational ocean modelling, we think we have succeeded.
Taking drift model uncertainty into account, we have found that the objects identified in most of the images can be associated with a single location within the previously-identified region suggested by other lines of evidence. Furthermore, we think it is possible to identify a most-likely location of the aircraft, with unprecedented precision and certainty. This location is 35.6°S, 92.8°E. Other nearby (within about 50km essentially parallel to the 7th arc) locations east of the 7th arc are also certainly possible, as are (with lower likelihood) a range of locations on the western side of the 7th arc, near 34.7°S 92.6°E and 35.3°S 91.8°E. While we cannot be totally sure which of these locations in the southern half of the 2016-proposed search area is most likely, we do have a high degree of confidence that an impact in the southern half of the 2016-proposed search area, near 35°S, is more consistent with detection of debris in the images than is an impact in the northern half.