I sometimes fly around Charlotte, NC with my dad and on one of our expeditions we were cautioned of mild turbulence near the end of the rnwy we were on final for. We didnt take much notice because we had flown our Centurion into things worse than "mild" turbulence. As we lined up on final the left cowling all of a sudden got sucked off the plane and flew straight up ,and back behind us[:-]. I have no idea still to this day why the heck it flew off ,because all of the cowling screws were still in place when we inspected the airplane on the ground. Anyways a few monts later we recieved a phone call from a farm up in the charlotte aera saying he had found an aircraft cowling that matched our "wanted" add we had set up around the airport. We quickly got it back and saw for some reason the only damge to the cowl was the holes where the screws should have been[&:]. This is still a real mystery to me today and has also been a big money pit for getting the replacment cowl for no reason.