As a young American passing through Heathrow on my first trip overseas, I stood with my suitcase, waiting to get on a shuttle. A stewardess, descending, looked at me and said, "Catches fall off." I checked the catches on my suitcase, and they seemed to be fine, so I started for the bus again. She planted a hand firmly on my chest and said, pretty sharply, "Catches fall off!" It took a long time to perk through my brain that what she was saying was "Coach is full, luv."