I'm not sure they're using a USP double action/Single action as opposed to a double action only. I mean maybe they are, I just don;t know that. Do you? I seem to remember (but am not sure) a pilot telling me he was carrying a SIG, though I don;t remember which model.

If in fact though, as Russ says was postulated, the AD occurred after the trigger was locked and then pushed further down in the holster, it seems as though very little foresight was given when choosing the lock and holster. But when I look at the picture that somebody posted above, that doesn;t seem probable.

ALL is possible in Government service and regulation - that I can attest to.

Locking up legally-owned and legal-carry guns....it's just funny stuff.