[fso301]

And so far the only proof we have that’s it’s in the Indian Ocean is the word of the leader of an Islamic county

Not correct. Data from the British company Inmarsat is what indicated the crash site as being in the South Indian Ocean.

[bigbob]

I haven’t seen that actual data, but I did listen to a video from an INMARSAT spokesperson who only gave a very general reference to having used doppler calculations to determine the southern route was “most likely”. He also added that this is the first time in their 34 year history they have ever attempted to locate a missing plane by this method, and went on to give a commercial for mandating the use of tracking systems like ADS-B (which I agree with).

My comment should have bee more specific, that the Malaysian PM is the one who made the absolute no-doubt proclamations. What I heard from INMARSAT was more tentative. Still, it’s a big ocean, and a crash at sea has always been the most likely outcome. I’ll accept the INMARSAT analysis, but I guess I just don’t have a good enough sense for why no debris has been recovered yet.

[bigbob]

Let me add my other concern about the INMARSAT analysis. Based on the very cursory explanation given (and echoed by the media) they used doppler analysis to determine the frequency shift of the “ping” signal and then determined that the southern route was the best fit model for the data observed. What I’d like to understand is how exactly INMARSAT measured the frequency of the ping with such precision?
Speed of airplane = 600 miles per hour
Speed of light = 670,000,000 miles per hour
SA/SL = 9e-7 * 1,600,000,000 HZ = 1400Hz

This requires not just capturing the data (digital message from Flt. 370) but the exact frequency of that signal at the satellite’s uplink receiver. Was this capability onboard the satellite, and why would it be, since it’s not needed for normal communications purposes and satellites generally don’t carry any extra mass. Also, given that the satellite drifts in it’s geo-sync orbit in a figure-8 pattern, it was moving toward and away from Flt. 370 at the time also.

I can accept that INMARSAT would be able to factor out the station-keeping drift of their satellite, but to fully accept this analysis, I’d really like to see a breakdown of the data format from the satellite to ground that shows exactly how and with what precision the frequency of each received signal is measured, and communicated to the ground so that doppler shift could be calculated.