Rod,
Not sure if it's an invasion of privacy or not.
The Captain's name is on the flight plan, which is accessible to a lot of people, admittedly not easily to the man on the street.
Seems a little like finding out that I am the owner of a house: that can be discovered if you know where to look. That doesn't necessarily make it an invasion.
In the end, we have libel and slander laws, I guess. Let's not get too prissy.