Departure track anomalies


#1

I have been noticing some odd flight tracks during departures. At first I thought that some of my friends were going crazy, but here is one of my flights:

http://flightaware.com/live/flight/N8960N/history/20080603/2010Z/9F8/KFSD.

I took off and turned on course; there was no circle, even though one is depicted.


#2

Did you have your transponder on during taxi?

The first handful of entries in the tracklog are curious.


#3

The airport is below radar coverage, so there would be no transponder returns, and I taxied northwest, not southwest as shown, and departed southeast, not southwest.

It seems to me that the first valid position is the 14:00 position, which is about a mile east of the airport. Tthat was about the right altitude for initial radar contact. Shoot, I never even drove through the 13:55 position.

Does the track start when I got my clearance? I speculate that my radar target was in COAST. The picture is a jump from the airport, then a phantom track to the southwest, and then a jump to the actual 1400 position.

The other unusual tracks also occur below radar coverage. See, eg, this track, which shows an airplane passing through a mountain, below radar coverage.