Hostname: page-component-89b8bd64d-nlwjb Total loading time: 0 Render date: 2026-05-08T06:51:44.181Z Has data issue: false hasContentIssue false

Final two MH370 communications suggest controlled eastward descent

Published online by Cambridge University Press:  03 December 2024

Vincent Lyne*
Affiliation:
University of Tasmania, Hobart, Tasmania, Australia
Rights & Permissions [Opens in a new window]

Abstract

Official interpretations of Doppler shifts from the final satellite communications of missing Malaysian Airlines MH370 were based on a motion-decoupled ‘Up-Down model’. That model predicted an uncontrolled high-speed gravitationally accelerated dive following fuel starvation. Here, I challenge that model using a more-realistic motion-coupled ‘Declination model’. Aerial, satellite and underwater searches failed to find the predicted official violent crash-site near the 7th arc. Meticulous re-examination of debris damage by air-crash investigator Larry Vance concluded that the aircraft glide-landed under power with extended wing-flaps. The trailing-edges were then damaged, broke off their mountings, flailing about and retracted along the guides to cause the observed wing-flap damage. Larry's conclusions complement interpretations from the ‘Declination model’ which we demonstrate here with three example flight tracks. Our revised Doppler-shift analyses support the hypothesis of a controlled eastward descent. We conclude that the official theory of fuel starvation and a high-speed dive are fundamentally flawed.

Information

Type
Research Article
Creative Commons
Creative Common License - CCCreative Common License - BY
This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution and reproduction, provided the original article is properly cited.
Copyright
Copyright © The Author(s), 2024. Published by Cambridge University Press on behalf of The Royal Institute of Navigation
Figure 0

Figure 1. Figure adapted from Lyne (2023c) comparing the respective northern and southern pilot-in-command (PIC) simulated tracks (left-side purple labels) with the planned tracks (right-side green labels). The PL hole is near where the 33°S latitude intersects the longitude of Penang (thin brown vertical line) at a 6,000 m deep hole. The decoy tracks (to Southern Ocean and Perth Airport runway) were not executed but merely to cause confusion. Track lengths are noted in the labelled track boxes. The Jindalee Over-the-Horizon Radar Network (JORN) range and southern boundary from Laverton are drawn in purple. The Decoy Track to Perth is inferred from the other in the simulator track. Note that the map is not in equi-distance projection

Figure 1

Figure 2. Map features and example flight tracks. White curves are the 7 arcs. The purple curve and inclined horizontal line are the Jindalee Over-the-Horizon Radar Network (JORN) range boundaries (but ignore the curve past the southern boundary). Three flight tracks are shown: (1) in yellow (1: ‘South track’) the southerly track intersects the 6th arc near 94°E, then veers to 33°S, 95°E at the 7th arc, and then proceeds east to the ‘Penang longitude’ location (red circle); (2) in green (2: ‘Adelaide track’) the southerly path veers east towards Adelaide at 92°E and 31°S; (3) in red (3: ‘PIC track’), shown as a dashed red line, is the pilot-in-command (PIC) track where the southerly track along 92⋅5°E veers south-east once past the JORN southern boundary at 30°S. The bearing to the satellite is shown by the light green northwest line. The light orange line running northwest is one of the simulation tracks from the pilot's home simulator. Other place marks are referred to in the main text or are for general background information

Figure 2

Table 1. Ancillary parameters for the BFO calculations

Figure 3

Figure 3. Comparison of horizontal and vertical motion coupling between the Up-Down model of previous investigators (left model) with the model of coupling between horizonal and vertical via a declination angle from the horizontal (right model). The up-down horizontal Doppler shift is assumed to be compensated by the SDU, so BFOs are attributed solely to the vertical dive motion

Figure 4

Figure 4. Variation of BFO error (Hz), compensated for horizontal motion, with track angle in degrees clockwise from north, and declination angle down from horizontal. The approximate aircraft to satellite direction is at 141⋅6° track angle (and elevation angle of 38⋅8°) where BFO changes are at a maximum across track angles for any given declination angle. At this track angle, BFO changes of over 325 Hz are possible for a declination angle of 25 degrees. Dashed lines refer to the different tracks in Figure 2: yellow is the ‘South track’; green is the ‘Adelaide track’; and red is the ‘PIC track’

Figure 5

Figure 5. Variation of BFO with declination angle. Black line is for a nominal flight track heading directly to the Inmarsat satellite – representing the maximum BFO possible by track angle. Other tracks are as shown in Figure 2

Figure 6

Figure 6. Variation of BFO (Hz) according to the Up-Down model where horizontal speed is invariant with track angle, and hence horizontal compensation does not vary with track angle. For comparison with the Declination model, we used the horizontal speed at the 180° track (a track angle has to be chosen for comparison as the main point of this comparison is that horizontal compensation in the Declination model does vary with track angle for positive declination angles – Figure 4)

Figure 7

Figure 7. Variation of the speed multiplicative factor with declination angle. Horizontal speed varies simply as the cosine of the declinaton angle, and vertical speed as the sine

Figure 8

Figure 8. Variation of horizontal BFO (Hz) compensated by the satellite data unit (SDU) (hence BFOs are negative) for the Declination model. Some variation with declination angle is seen at the south track (180°) but the greatest variation is at the satellite track angle (~141°)

Figure 9

Table 2. Summary evidence against high-speed crash (left column) and for controlled eastward descent (right column)