A brown guy taking photographs on public transportation? :)
Anyway, on the NJ Transit back from the City, the conductor told me in no uncertain terms, "It is not permitted to take pictures of equipment on this train." I had my camera pointed out the window at a particularly picturesque (for urban New Jersey) bridge in the lowering sun ... "You need a permit." "Can I take pictures out of the window?" "You need a permit." I demurred. Wrong color, international flight to catch, don't want no trouble. :: sigh ::
I did snap this picture of "equipment" at Seacaucus station ...
And no one has, to date, asked me to not take pictures at the airport. Of course, it's illegal in India ... but we all know this. In the US? Go to salon.com and search for back issues of Patrick Smith's "Ask the Pilot" column -- he had a great piece a few months back about being asked to refrain from taking pictures at various airports. He checked with TSA and apparently, it's not illegal at all. But then, he can talk back. He's white. :)