Penthouse?
Obviously, none of you have read a Penthouse lately. From what I understand, they show everything short of actual intercourse.
Also, what about the legality of displaying this stuff in front of minors? If they keep it shrink wrapped and on the top shelf of the airport magazine stand, obstensibly to keep minors from reading it, why would it be okay to flip it out on the plane? And if the nudity is okay, what if he had taken off his clothes? Granted, a 14 year old girl may know about sexual matters, but that doesn't mean she's seen actual content such as what's published in these magazines.
I found the responses to this post quite interesting. A situation like this where you are unable to escape the sexual content is certainly different than one where avoiding it was a simple matter of walking away.