On September 19, 1993, about 1430 hours eastern daylight time, N88RD, a Robinson R-22 helicopter, operated by the pilot/owner, impacted terrain and was substantially damaged during an attempted go-around in Scottdale, Pennsylvania. The certificated private pilot and pilot-rated passenger were not injured. Visual meteorological conditions prevailed and a flight plan was not filed. The personal flight originated from Latrobe, Pennsylvania, about 1400 hours and was conducted under 14 CFR 91. According to the private pilot, he invited a certificated helicopter flight instructor friend for a "sight-seeing ride." It was agreed that the private pilot would be the pilot-in- command. About 20 minutes into the flight, the private pilot decided to land near a rock quarry to observe an excavation site. After a "normal" approach into the wind, the pilot observed that the terrain "appeared uneven". He decided to discontinue the approach, "but found power was not available to climb." The helicopter descended onto the uneven terrain, touched down on the left skid, and rolled over onto its left side. According to a FAA aviation safety inspector, the helicopter's fuselage, main rotor system, and tail rotor system received substantial damage. No pre-impact mechanical deficiencies were reported.