Anyhow, this is the best I could do to "reconstruct" their "reconstruction" of the south track. Scales are different, I have no idea why. Even the zero in the original chart is not a zero. (The "knee" around 20:00 UTC corresponds to the Doppler shift going through zero and changing sign as the aircraft passes the closest approach to the satellite, somewhere near the equator.) But at least qualitatively there's an agreement:
http://i61.tinypic.com/abo2n7.png This corresponds to the aircraft going off at heading 185 at 450 kts from 18:30 UTC and beyond.
Interesting, hamster3null. One question - how does it look at lower or higher speeds? Do you get the same profile but just at a different heading? Or does the plot actually differ?
(As I understand it, and I may be wrong or missing something, they don't know the actual speed of the aircraft, or even that that speed was constant over the 7 hrs. Rather, they only know the difference in relative velocities at points in time. As a result, while the velocity and position for the satellite are known, one has to posit assumed heading/assumed speed pairs for the aircraft, each of which give the same difference in relative velocity, but correspond to a different track in real life.)