$quoted_author = "Jan Whitaker" ; > > Interesting analysis. I don't know enough about the way ATC uses any > ACARS data during conversation to know if the sequence below is > relevant. Can you clear this up for me? I mentioned to a friend I'd > ask someone in the know. :-)
So there have been 4 ways the plane has been tracked: - Active transponder which tracked the flight from take off till the time it "disappeared". It appears to have been deliberately switched off. http://en.wikipedia.org/wiki/Automatic_dependent_surveillance-broadcast - ACARS transmissions. These are automated uploads of operational data to the airline and manufacturers. It appears they were only occurring every 30 minutes on MH370 and the last one was about 20 minutes before it "disappeared". These transmissions appear to have been deliberately stopped. http://en.wikipedia.org/wiki/Aircraft_Communications_Addressing_and_Reporting_System - Military radar appears to have tracked the original change of course till the flight was near Phuket. - ACARS signalling. Much like your mobile phone constantly communicates with the nearest cell tower even if you are not on a call, the ACARS system does a similar thing with the satellite via which it would send uploads. The satellite is geo-stationary so using the round trip latency of these signals has enabled the plotting of 2 tracks, one "anti-clockwise" over Asia and the other "clockwise" out over the Indian Ocean. See the two images in http://blogs.crikey.com.au/planetalking/2014/03/17/mh370-update-has-co-pilot-saying-all-right-good-night/ The coverage has been fairly sensational. The best reading has come from Ben Sandilands http://blogs.crikey.com.au/planetalking/ and Simon Hradecky http://avherald.com/h?article=4710c69b&opt=0 cheers Marty _______________________________________________ Link mailing list [email protected] http://mailman.anu.edu.au/mailman/listinfo/link
