Years ago I worked for a well known touring rock band. We had a bus driver who was notorious for nodding out at the wheel. I had to keep a volunteer up front to watch him until I could get a replacement driver flown in. Pretty scary stuff. When you get in your bunk for sleep you are at the mercy of the driver. Back then almost all drove double shifts. There were no log books and no enforceble sanctions.
First thing that came to my mind was Cliff Burton.