On long trips I have always cartopped my boats with just a cockpit cover. The type with a strap that goes around the boat. I've tried using full covers but found them to be unwieldy and not worth the effort. Also, I use the boat to hold my paddling gear to free up space in the vehicle.

Dan

   Me too Dan. Did 6200 miles in July Aug on top of truck. This summer. A full boat cover is a thing that must be form fit. Any looseness and the wind will flap it taking the finish off the boat.

   .....full covers are things that racers sometimes use but not universally. It is also used by builders delivering high and custom boats, but they are done once, and tight.

   I'm convinced - cockpit cover only - I was leaning that way anyhow after considering the extra work of using a full cover and the potential for damage to the finish.

   I have a fairly tight fitting tailored cockpit cover that I made for my Mill Creek. I have put in a lot of miles at highway speeds without any issue. I carry the leeboard, rudder, lifejacket etc in the cockpit. I do put an additional elasticated strap on the front of the cover to ensure it doesn't lift up. It's probably not necessary, but it reassures me !