The conventional wisdom on carrying a knife on a US domestic airline is to keep it an inch under the hard regulation maximum of 4", and keep it plain edged because teeth look carnivorous, and keep it inexpensive just in case. No fixed blades and no automatics.
So far any pocket knife I've put in the little tray at the airport has been ignored, other than an "Oh brother!" from one guard as the tray filled up with more and more metal - Leatherman Wave, Spydercard, a few pens, a bunch of pocket change, keys, Dragonfly, Photon Lights - and that's with the rest of my usual knives in the checked baggage.
So far nobody at airline security has been interested enough in my knives to open them, to find out there are dreaded serrations on the Dragonfly and the Wave. But what if they open the Speed-Safe?
The Speed-Safe is not an "switchblade" because Kershaw's attorney has disected the definition of a switchblade in federal law and concluded that it isn't, and so far the issue has not been tested in court, and the jungle telegraph doesn't report any unfavorable reactions from authority figures. This may be because people with Mini Tasks and such have not snapped them open in front of authority figures.
Caution says not to give authority figures a chance to ponder whether or not a Speed-Safe is a "switchblade" if one is in a hurry to go somewhere. I think the odds are that the guard will think it's small enough that he won't bother to open it. If he is familiar enough with pocket knives to know what to do with a thumb stud, he might think it's cool, and that might be a good thing or a bad thing. If he is not a "knife person," he'll probably pull the blade open two handed, and then he might not appreciate the significance of the different way it feels.
Matter of fact, when I show an auto to a non-knife person, they typically try to open it two handed, and wonder why it won't open. So I show them, letting the blade ease past my fingers rather than doing a full-speed snap that startles onlookers. They then try it themselves, two-handed, and don't understand why it's awkward. And they also don't understand why there's a law about pocket knife mechanisms.
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- JKM
www.chaicutlery.com
AKTI Member # SA00001