The Waypoint Hypothesis is one slash of an “X,” a simple waypoint pathway. Current search efforts utilize satellite data to define a pathway. While I firmly believe Inmarsat satellite data is accurate and usable, the Waypoint Hypothesis does not assume the data is correct or necessarily depend on it.
Current search efforts also rely on two other measures to define the end of the pathway:
- The last satellite transmission, which provides a distance from the satellite along the waypoint path; or
- The estimated maximum fuel range of MH370, which is believed to be close to where MH370 crashed
It substantially strengthens the hypothesis if both of the above cross the pathway at the same point. As I described shortly after formulating it, the Waypoint Hypothesis provides one slash of an “X” and one or the other or both of the above data provide the other slash. It just so happens the last satellite ping and the fuel range above may coincide all at the same point on the path predicted by the Waypoint Hypothesis.
The point where the waypoint path intersects the last satellite ping ring is very near S40.1743 E84.6945 and is shown in the figure below:
The point is south of the current search area and it is not planned for searching this campaign, (ending in May, 2015) or perhaps ever. The reason they are not searching at the X is at least partly because they do not believe MH370 could have made it there based on available fuel. The fuel range depends on how much fuel MH370 burned before it got to MEKAR, and these assumptions have changed over the past year.
The intersection of the current official fuel range provides two unique points along the arc as illustrated in an ATSB investigation report figure (white annotations are my own):
The yellow line in the above figure is the fuel range (performance limit), and the white arc it intersects is the 7th arc representing the last satellite transmission. Most independent investigators and the ATSB assert/assume/believe that:
- MH370 is essentially along or close to the 7th arc, because the last satellite ping was very close to the crash time (within 2-12 minutes, if not less), and
- the crash was because the plane ran out of fuel between the 6th and 7th arcs, and the 7th arc ping is caused by a Satcom logon due to emergency power restoration after fuel exhaustion.
If the above are true and the performance limit is accurate, the plane can only be close to the northern or southern limits depicted in red. The two assertions above are fundamental to the current search, yet the search has proceeded between the two limits despite a prediction the plane had fuel to fly well past the 7th arc, which violates both assumptions above.
In reality, the performance limit is subject to debate, as are the assumptions. The performance limit is probably the least accurate and has changed over time, causing the search to move. The fact remains, however, that the most likely location of MH370 is where the best estimate of fuel range (yellow) and an imaginary arc (fuel exhaustion) between the 6th and 7th arcs intersect. I have added an extension to the southern limit in the above figure to reflect the belief that MH370 ran out of fuel between the 6th and 7th arcs. At the end of this extension is where the southern limit should actually be. Anywhere away from these northern and southern limits must be considered less likely given the generally accepted assumptions. Unless you believe the plane is back to the north beyond the Zenith Plateau, there’s really only one likely location, the southern limit (more correctly placed at the end of my extension).
It just so happens the Waypoint Hypothesis predicts an endpoint (S40.1743 E84.6945) that is compatible with the southern performance limit extension. The Waypoint Hypothesis endpoint is just a little southwest of the performance limit extension. Several investigators have looked at locations near this point and have come to differing conclusions as to whether MH370 could have made it there or not. We would expect the location of MH370 to be at a point where we are not quite sure it could make it to if we believe the two key assertions above. This is because the location would be near to where MH370 ran out of fuel and different assumptions would come to different conclusions. If some experts say “pretty sure yes it can make it” and some say “no, probably not” as they do now, I figure it’s the most likely point and X again marks the spot.