The AC cowling almost flew off as we drove across Oregon earlier this week. The *idiot* who put this thing on didn't use lock nuts, so it all kind of worked loose. The remaining nuts could be removed by hand! The wind caught the front end, and if I hadn't gotten lucky and looked out the rear view mirror at the right time... WOOSH! We pulled over and held the thing down with what we had: Our Friend Duct Tape.
(Click to Embiggen!)
Gorilla tape over the cracks and BIG washers. And, of course, lock nuts!