As they say in the land of the free "no good having common sense, if you've got rules!"
On one of my more interesting jobs a few years back, I had to get from Basrah to Kandahar in short order. Managed to hitch a lift on a flight leaving at early o'clock and was pretty much the only one on board. Walked up to the check in desk carrying rifle, pistol and enough ammo to see you right in Moss Side on a Saturday night only to be asked by the straight faced and deadly serious RAF copper "are you carrying any weapons sir?"
So I had a rummage round and handed in my pen knife which I had in my pocket
Don't think he saw the funny side of it.