Are you asking about flights in China? Here in Canada, it is pretty simple for domestic flights. We need a passport or some other type of photo identification (driver's license, health card, citizenship card...something with a picture and your name). Actually, if you have these other cards, you don't even need a passport. If I choose to leave Canada, I will need a passport, citizenship card (permanent resident card, landed immigrant papers, or birth certificate), usually any VISA papers and study/work permits for the other country...Anything to prove that 1) I am Canadian, and 2) I have permission to legally enter the other country... Does this help at all??