A United Airlines flight en route from Newark, New Jersey, to Denver made an unplanned stop in Chicago on Sunday (August 24th) after two passengers got into an argument over reclining a seat.

The dispute was over a man using a gadget called the Knee Defender that attaches to a passenger's tray table and prevents the person in front of them from reclining, which blocked the woman in front of him from pushing her seat back. Although they are legal under FAA rules, United, like all major U.S. airlines, bans the Knee Defender, and a flight attendant asked the man, who was on his laptop, to remove it. He refused, and the woman threw a cup of water at him. That's when the flight crew decided to divert to Chicago, where the plane was met by police and TSA officers. No charges were brought against the man or the woman, but the flight went on without them.

Spirit Airlines and Allegiant Air might have the right idea, avoiding this problem altogether by taking the reclining mechanism out of their seats so they can't go back at all.