Does Airlines across the globe maintain a checklist of passengers that have actually boarded the aircraft? Can't speak for other countries, but in the US there is a passenger list, and records indicate whether a passenger has merely checked in, or whether the passenger's boarding pass was "lifted". Lifted means someone gave the boarding pass to an airline employee as they boarded. That still does not guarantee the person is on the plane; he/she could have turned in the boarding pass and suddenly changed his/her mind, or the boarding pass could be lost/stolen and used by someone else. They are unlikely scenarios, but still possible. At any rate, a lifted boarding pass is the best indication someone is on the plane.In the US passenger records are considered confidential and employees will not give out info to just anyone who asks. I work in airline reservations, and if a caller asked me "Was John Smith on the flight from Paris to New York?", I would definitely not give them any information. I WILL give information if they say, "Was John Smith on Flight 003, his confirmation number is 1A2B3C". That person obviously knows enough already, it's safe to give out additional information. |