A man and a woman are sitting next to each other on a trans-atlantic flight in a Boeing 747-400. The aircraft encounters severe turbulence and the man, looking out the window at the wing bouncing around, gradually looks more and more worried.
The woman, noticing, says “Don’t worry, I’m a flight attendant and this is perfectly normal.”
He replies “Miss, I’m a Boeing engineer and we didn’t design the wing to do what it’s doing right now.”