So the news for the last couple of days has been full of the pilot who had a brain malfunction and fired a round of .40 Smith and Wesson through his Airbus the other day. That is a Bad Thing. Apparently the FDO's are either issued or required to buy Heckler & Koch USP pistols. These are not unreliable firearms as long as the right ammunition is used, and the wrong ammo is still not going to make the things go off by themselves. They're also not going to fire because someone bumps one or drops it on the floor or, for that matter, hits it with a hammer. If you have an ND, then you didn't mean to pull the trigger, but nevertheless you did and have no one else to blame.
But if Paul Huebl at Crimefiles is right, it's possible that the pilot didn't choose to fiddle with his pistol's trigger in the cockpit, but was required to do so by the TSA. Sound too stupid to be true? Do I need to remind you that this is the TSA we're dealing with here? Go read it and see what you think. The miracle under those conditions is that it took this long to have Very Bad Things happen.