Originally Posted by
DaveReidUK
The circles (assuming that more than one could be plotted, which now seems in doubt) would be 60 minutes apart, because that's how often the satellite pings the aircraft.
The only deduction that could reasonably be made would be if the spacing between two successive rings turned to be equal to the maximum distance that the aircraft could fly in an hour. Then it would follow (as previously suggested) that the track must be along the radius of the rings, but of course that doesn't identify which radial.
If two hourly rings are spaced closer together, then it's hard to see how anything can be deduced in respect of track or groundspeed.
But as it seems that only one ring is known, it's all a bit academic.
But if 3rd hourly ping is at the same reduced spacing to the 2nd one , as the 2nd one is to the 1st one that constant spacing tells you it is on a constant heading/trk but nothing about that heading or track.. Do you agree that?
Now you may think that is unimportant or of no use others will disagree a) it is an extra known and B) in IMHO it indicates a flight south, constant track north is eventually going to be spotted by the ground or another aircraft visually.
There was also another post by someone on rhumb lines and loxodromes and he reckons with the other ping arcs you could calculate track and heading do a search on the thread. Way over me.