My guess is that a tactical looking knife might get you into trouble.

I would have a tendency to carry only a medium size Swiss Army knife, in your checked bags when you're on the plane. When you disembark, put the knife in your jacket pocket. If you get questionned for whatever reason (you pulled it out in a restaurant next to a table featuring 4 elderly women babbling and eating), you can argue that you use it all the time for all kinds of things. If they want it, just let them have it.