A United flight from Newark to Denver was diverted to Chicago after a fight broke out over a controversial contraption called the "Knee Defender."
A male passenger seated in Economy Plus, which allows four more inches of leg room, snapped one of the "defenders" on his tray table, making it impossible for the woman in front of him to recline her seat. United bans the devices and a flight attendant asked the man to remove it. When he refused, the woman in front of him hurled a cup of water in his face. The fracas led to the plane landing at O'Hare and the two sparring passengers deplaning (neither was arrested).
Shockingly, the FAA only bans defenders during taxing, takeoff, and landing. They were invented over a decade ago, but haven't really caught on — possibly because most people aren't as insensitive as the jerk on Sunday's United flight.