ManiacQuilter has the only real concern (BTW: I love that name!) - dimensions. I worked in the electronics industry, and I have carried all kinds of very odd pieces of equipment through security as carryon items. There have been times when I've been asked what the equipment was, and I certainly have had to take it out of packaging a few times, but I've never been turned away or had the equipment confiscated. You do have to be really careful about the dimensions though. I generally have to fly a small plane (25-50 passengers) to a larger hub airport. The amount of space on those little planes is astonishingly small! I would think a Featherweight would fit under the seat even on those planes though. Even on big planes the airlines are beginning to enforce their long-existing rules for carry on sizes (thank goodness - this is a pet peeve of mine!).
Pam