Larry Dighera wrote:

In this case, it is unclear to me that the 14 year old is guilty of
trespassing. The airport and aircraft were unlocked, and I have heard
no mention of signs being posted.

In many (possibly most) States, charges of simple trespass can only be pressed
if the individual was told (orally or in writing) not to trespass on the
property. If, however, the individual commits a crime on the property and the
perpetrator was not invited onto the property, that is "criminal trespass." This
is usually a misdemeanor with relatively trivial fines and/or sentences.

George Patterson
Why do men's hearts beat faster, knees get weak, throats become dry,
and they think irrationally when a woman wears leather clothing?
Because she smells like a new truck.