Originally posted by HN39
However, in the preceding 20 seconds we see the opposite trend: the airplane seems to descend steeper based on pressure altitude than indicated by the radio altimeter + terrain profile. Do you have an explanation for that?
The short answer is no - or at least nothing really convincing, just a couple of thoughts.
There may be two effects with opposing trends involved; the effect of height at more or less constant AOA and the effect of AOA at constant height. This will be complicated by the fact that the AOA effect is very possibly more powerful at low heights than far off the ground. The motion seems to consist of one part with reducing height at more or less constant AOA and the other part increasing AOA at more or less constant height. OTOH, ground effect is rather weak above, say, 50ft so one would not expect any significant effect from the first trend over much of the relevant sequence.