The RV6A nose gear has very little ground clearance on the nut that holds the yoke to the gear leg. This guy landed hard in a flat attitude and the nut dug into the turf flipping the plane. This is a common accident for RV trikes even on asphalt. Van's now has a revised yoke that gives more ground clearance but it is mostly a pilot error problem as it is easy to hold the nose wheel off landing a RV. Don