depends on which Airport your at unless you work there and are pulling other people that work there, in my opinion there are to many variables to deal with and your better off just going somewhere else to have sex.
Some airports have hotels etc. in them or places with beds so thats might work depending on which airport toilet pull might work but highly likely security will on to you
if you are in non crowded airports some places are baron for a couple of hours just because there are no flights shecduled to leave from those terminals etc. you might see one of 2 people sleeping there but if your discrete you might be able to pull something off there (she would probably need to have a skirt on for easy access)
Anyways just for my own curiosity why you need Airport sex logistics ? (if you dont mind me asking)