Flightaware must use mode c as I conducted an IFR flight in a cherokee last weekend and to my surprise the entire flight was tracked and available for viewing there.
One things for sure , theres no ADSB in this old girl.
With the exception of the final descent, the entire flight was in radar coverage however.
One further point later that day I flew back along the same route , this time VFR and no plan. This flight did not get tracked so can only assume , you need to have a flight plan lodged or perhaps IFR for tracking to occur.
Last edited by Harro; 16th Mar 2012 at 08:49.