If possible I think it would be right to let the highest points at the airport have beacons.
I think Werner had already mentioned something like this before: http://site2.yowindow.com/forum/viewtop ... 937#p10621
Furthermore I think some cars at the fligh-over drive at an extremely high speed.
Unless of course these are salvation vehicles (ambulance, police, firebrigade). Then they need beacons as well.
It's probably easier to have their speed reduced, right?

Fred