Thanks for your feedback. Yes, you are correct that once the aircraft’s transponder is turned off Flight Aware (or any other radar site e.g. Flightradar24) would not be able to track the aircraft.
FlightAware recorded the aircraft’s last position at 1:02 AM Malaysian Local Time on 8/3/2014.
This was at Latitude 4.7073 and Longitude 102.5278.
However, FlightRadar24 was able to track the aircraft all the way until the transponder was turned off. This was at 1:20 AM (Malaysian Local Time) which is 18 minutes later at a position Latitude 6.93 and Longitude 103.59. This is about 269 kilometers further than Flightaware.
However, a few months prior on 15/11/2013 Flightaware was able to track aircraft much further north to latitude 13.8598. This is approximately over a 1000 kilometres further.
Note, this is using actual fixes from ground stations (i.e. the Flightaware system was not just estimating the position fixes).
So it appears Flightaware had sufficient coverage to track MH370 all the way until the aircraft transponder was turned off (and beyond).
So my question is how come the coverage stopped a lot earlier i.e. about 269 kilometers prior FlightRadar24.
If someone could let me know it would be much appreciated.