My wife is a flight attendant with US Airways and states that anything under size 6/0 is supposed to be fine. I suppose as previously mentioned that is always at the discretion of the security agent.
I predominately fish inside the GSMNP and suspect that the 3wt would handle the situations that I fish just fine (typically no droppers), typically largest I throw is a size 16.
John S or anyone else, what are your thoughts on the 3wts? Are they somewhere in middle between the 2 and 4 or do they lean more towards the light (2wt) side?