Winglets and bumpy paint?

[VetteOwner]

hmm same principle applies to golf balls... they dont go mach 1...might as well try it...

[kitcar]

You could use the "stone chip" coating that manufacturers put at the bottom of some vehicles; that's pretty bumpy. But would the entire vehicle need it? If I recall, the entire airframe wasn't coated, just the leading edges where the ill fitting panels were. It was a long time ago and I wasn't allowed to shoot close up photos, just the long shots.