*Not a lawyer*
That's the fuzzy grey legal area of copyright law, I think. Most fair use falls under 'commentary and criticism' or 'parody', though; using another's work for your own financial gain is pretty much the definition of what copyright law is trying to stop, so I would suggest you avoid the situation if possible although yes, there is some degree of 'transformative' that would exempt you (although it seems like it needs to be pretty drastic).
Workarounds, based on your link:
-Images taken by a US government employee in the course of their work are not subject to copyright. I'm not sure about other countries. That may take a bit of looking, but I'm sure you could find something on the TSA website or a government report.
-Look around for unrestricted photos. Wiki Commons is a good source for that. This image
isn't restricted, for instance, and you could do a lovely something with it just by removing the background and applying a filter/grayscale.