The plane’s terminal location is not yet known. What is known with reasonable certainty is that it is in the Indian Ocean south of the equator. We also believe we know it is on or very near a point about 4,907 km southeast of Inmarsat’s 3-F1 satellite position at 00:19 UTC March 8, 2014. That is the so-called Seventh Arc, and only about 4,000 km of the arc passes through the Indian Ocean between Java Island, Indonesia and the farthest point southwest of Java where the plane is believed to have been capable of flying with the fuel it had.
The initial search was predicated on an assumption that the plane flew in a straight line, more or less, and came down when fuel was exhausted on the Seventh Arc at -38.0 S, 88.5 E. We now know the plane did not fly to that location after two years of fruitless search.
However, the Seventh Arc as a concept is still believed to be viable. At least, it has not been shown to be incorrect. If it is viable, the only portion of the Seventh Arc that has not been surface-searched or scanned is the portion of the Arc that crosses Zenith Plateau from southwest to northeast and ends on the shores of Java. This area is known as Wharton Basin after a large, deep basin spanning hundreds of kilometers.
At this point, no documented searches have been conducted in Wharton Basin.