On May 24, 2011, about 1400 Pacific daylight time, a newly built Hoskins Zenith CH-701, N34NH, sustained substantial damage when it landed hard at Pierce County Airport – Thun Field, Puyallup, Washington. The commercial pilot/owner, the sole occupant, received minor injuries. The airplane was being operated under the provisions of 14 Code of Federal Regulations (CFR) Part 91. Visual meteorological conditions prevailed and no flight plan was filed for the local flight. The pilot reported that after two uneventful landings on a paved runway, he proceeded to circle the airport about 2,000 feet above the traffic pattern to familiarize himself with the airplane’s power settings. The pilot elected to conduct a third landing onto a grassy area parallel to the runway. The airplane approached the landing area at about 32-35 mph with the flaps retracted to the full up position. The pilot stated that about 10 feet above the ground, the airplane was a little high and fast. He reduced power and pitched up to slow the airplane when the nose of the airplane suddenly “dropped.” Subsequently, the airplane’s nosewheel dug into the ground and the airplane nosed over, coming to a rest inverted substantially damaging the rudder, firewall and wing struts. The pilot reported no mechanical malfunctions that would have precluded normal operations. The pilot’s total flight experience was approximately 5,580 flight hours; of which, about 7 hours where in the airplane make and model and 4 in the accident airplane. During a telephone conversation, a Zenith Aircraft Corporation representative reported that due to the airplane being a homebuilt airplane, exact stall speeds cannot be determined by the manufacturer. Although, generally, the approach speed for the Zenith CH-701 is between 45-50 mph, with the stalling speed of about 35 mph with the flaps retracted.