I don't have the keel root and bolt stats handy for our Malo 41, but this design got a serious real world test around the time ours was getting built. A Brit thought he was just fine entering a particular harbor in the south of England. Seems they had a concrete sill across the entrance to the harbor. He hit it at ten knots over ground. According to the in-house designer's rep at Malo, the bottom 2 feet of keel got sheered off and the bottom 2' of rudder as well. In his delightful Swedish flavored English and a twinkle in his eye, he said, "But you know, the boat did not take on any water and it could still be steered.... {long pause}... but it was rather expensive to repair." I'm confident that he did not make this up.

We hit a rock at about two knots a year after we bought the boat. We vowed never to do THAT again. So far so good. The owie was ground and faired and the result was as good as new (see first photo). Note that the leading edge is lead. The keel sump stair steps down aft, helping to absorb the shearing effect of a collision. She shaft log/skeg and floor fiberglass grid help keep the aft end of the keel from punching upward.

Okay, so this is not a super-high performance keel, but it is some type of NACA shape and we've held our own very well racing other cruisers.

Going from two knots to zero in 3 inches of crushing lead made a heckuva an impression on us. It shook the boat from bottom to masthead, even breaking the anchor light filament. I can't imagine an impact at ten knots. I would not expect any boat to survive that.