Rolf
The Tybee boat hit a manta ray that we had just sailed over with a span at least as wide as the boat. We hit bottom once with the 18 HT and broke a board and cracked the hull (the seams on the bottom split very easy). I have hit bottom with a N-20 and F-18 and had the boat stop and only had a few scratches on the boards. Like I said the HT is made for deep light air lake sailing.