what kind of data do airlines keep about their passengers who have taken a flight, and for how long?
Let's say a passenger travels somewhere. At check-in, they register baggage, weight of bags etc.. Do they save this info in a 'global' database under the passenger's name..? What else would be saved? Could they trace all the bookings and profile the passenger according to that information?
If they log some special information, let's say passenger had overweigh a couple of times, will this information be revealed at next check-in with the same airline - i.e. will the computer access the 'global database' and display the information? Same, if passengers had some trouble with the check-in, would they make a remark or something in the computer?
I guess the airlines act with the data protection acts in the country of check-in..