Nut backed off ball caused accident

Here's another tip: Don't ever put the cotter pin in the hitch lock on the trailer unless it is hooked up to the TV. I was always losing them while un hooking the hitch and equalizer bars etc so I stated to re install them when TV was disconnected so I would not lose them. Once I forgot to unclip the cotter pin and backed up the TV and pulled back the trailer hitch clamp/coupler over the ball with pin already in and lowered the hitch on the TV hitch ball and drove away. Didn't get far and thanks for the safety chains. Even with the pin in place I can still somewhat raise or release the hitch jaws but not far enough so the tongue can release from the ball. Don't be in a hurry!