The only thing I think FW could try to argue is PC §46.03:
If you were to have some sort of federal persons standing at the entrance searching bags, maybe FW could try and argue that the area was a "secured area." However: the airshow is certainly not in a terminal building of an airport. Of course when they try to argue that the FW Museum of Science and History and the FW Zoo are both educational facilities, I wouldn't put anything past them. Maybe the airshow is a polling place?PC §46.03. PLACES WEAPONS PROHIBITED. (a) A person commits an offense if the person intentionally, knowingly, or recklessly possesses or goes with a firearm, illegal knife, club, or prohibited weapon listed in Section 46.05(a):
(5) in or into a secured area of an airport.
(c) In this section:
(2) “Secured area” means an area of an airport terminal building to which access is controlled by the inspection of persons and property under federal law.