@KennethRWebster Airline lounges are best, and at their home base where they have more control. Emirates lounge in DXB T3 is like a 5* hotel. Same with QR in DOH and EY in AUH. All the stopover airports. Even the BA lounge in LHR is really nice.
@NewTwistedOwl@ProfessorPape The transponders use the same broadcast frequency as commercial airlines so that ATC and other planes know where they are. The tracking sites just use that broadcast data. As they get nearer the action they can go dark