I'm currently having the same issue. No physics warp whatsoever, its literally just as Mr.Rocket describes, for some reason it just suddenly flips with considerable force, almost like the terrain altitude is slightly different at the edge of the KSC zone. So far I've encountered this issue approaching KSC's Northern and Western edges. Using Rovemax M1 wheels within their described limits. Even if you can fly over it, the game is in Alpha and solving these bugs makes for a better end product. Best guess is its not user error, probably a glitch (might only occur while using the Rovemax M1's? will test further...).
