originally posted by Backoffice ...
... is it possible that the transmit time and receive time get shorter (by milliseconds) assuming the satellite is to the relative north of transmission, so if the aircraft turned south the transmit/receive time would increase
The satellite is geostationary over the equator and in theory the the path length will get shorter when proceeding south toward the equator. However, without highly accurate timing markers in a transmitted stream of data, there is no way of measuring the path length. Even if the satellite had initiated timing, a return signal to it would have passed through indeterminable delays in the aircraft receive/transmit path.
Many moons ago, I did check which satellite was being used, but can't remember whether it was east or west (possibly a few degrees east) of the LKP.
A good thought, but not practical in this case.
mm43