The scene is sometime in the old era when ****pits had round dials plus flight engineers and navigators. The crusty old-timer captain is breaking in a brand new navigator.
The captain opens his briefcase, pulls out a .38 and rests it on the glare panel. He asks the navigator, "Know what this is for?"
"No, sir," replies the newbie.
"I use it on navigators that get us lost," explains the captain, winking at his first officer.
The navigator then opens his briefcase, pulls out a .45 an sets it on his chart table.
"What's THAT for?" queries the surprised captain. "Well, sir," replies the navigator, "I'll know we're lost before you will."
ROFL!! I hope you weren't discussing that "crude image" with anyone... I swear, we must have perverted your mind up, its a dangerous thing around the workplace. :D