Can't get Event to work when in an Airship

[PMG]

I'm trying to have this barrier around an Island while on a boat it works fine, but when on an airship you just fly over it, I'd like it to work while in an airship if it's not possible we'll just work around it

[Kojinus]

Set an event right behind that one with a Priority of "Above Characters" that should stop them from being able to pass over it while in an airship.

(Necro post, I know. Sorry)