Is it possible to use a FP on U.S. national flights?

I travel with fountain pens all the time. I normally put my pen in my suit
jacket pocket (or inside my shoe) which, of course, goes through the
screening machine. I've also (in a moment of forgetfulness) have passed
through the personal screening apparatus without setting-off any alarms or
the concern of the TSA. Overall: never had any difficulties traveling with
my pen(s).

Paul