Related story (possibly cautionary): I took my bike to the airport (Newcastle) last year when I was away for a couple of days for work. Had a cursory glance around for a bike rack, but wasn’t really expecting to find one, as I thought I was probably the first person to cycle to the airport and leave a bike there. I locked my bike to the railings in front of the terminal, to make a point, and because it was the most secure place. I thought it might be a bit dodgy, but you can lock a bike up in a million other places it could be considered a threat.
Needless to say, when I got back, it wasn’t where I left it. I went to see lost property who told me the police would like a word. I waited a while trying to fathom what offence I could possibly have committed, before a couple of bored looking cops came to explain to me it wasn’t a sensible place to leave a bike (which obviously I’d already inferred from the fact that they wanted to talk to me). They gave me the bike back, minus the lock.
So if you want it to be really secure, and don’t mind a short wait on your return, just lock it right next to the terminal with a cheap D lock 😉
Tangent: I once got a tour of the control tower at Newcastle. One of air traffic controllers keeps his extremely expensive looking carbon road bike in the base of the control tower. Probably not an option for everyone though 😀