Two springs ago on our way down to Asheville we had 2 close calls within a few miles of each other. Both southbound on I-81 between Wytheville and Kingsport.
First we were about to pass a semi and right in the middle of the passing lane was a case of beer - had to slam on brakes and whip back into the right lane. Another semi had just sailed over it when it came into view, but that wouldn't have been the case with us... Second there was a semi with a flat open bed with something on it covered with a big white sheet of plastic. As we were driving behind it the sheet came loose and floated up into the air - I just knew that it was going to wrap itself across our windshield (besides tangling up around our wheels) and we wouldn't be able to see a thing or control a thing at 65 mph. Again we slammed on the brakes and swerved into the other lane.
Things like that make me very happy that my DH is a wonderful driver and quick thinker! (Also very glad we have our Hensley.)