Not trying to be my usual argumentive self here, Denny. But my interpretation here is, if this goes to court, the question will be whether Tropic was following the law. It seems to me that is not a question of the passangers responsibility to know the law as a question of Tropics responsibility to follow it.
Just for the sake of this stimulating conversation, the passangers could have boarded the plane and the plane taken off in legal VFR conditions. But if the pilot flew I into illegal conditions, that would be out of the passangers control, unless they hijacked the plane.
Further, I doubt if it is a legal premise that it is the responsibility of consumers to know all the laws regulating licensed operations. The purpose of license is to be sure the license holder knows the laws and follows them.
The premise of "ignorance of law is no excuse" (in my opinion) applies when someone breaks the law, not when someone is injured or put in danger because someone else breaks the law.
How do you rule on this one, Judge?