On February 22, 2002, about 1335 Pacific standard time, a Young Mini-500, N500JY, collided with power lines during the initial climb from a clearing about 4 miles southeast of Paso Robles, California. The airline transport certificated pilot/owner operated the helicopter under the provisions of 14 CFR Part 91. The helicopter was substantially damaged, and the pilot received minor injuries. Visual meteorological conditions prevailed, and no flight plan had been filed. The local area personal flight was originating at the time. The pilot reported to the National Transportation Safety Board investigator that, at the time of the accident, the visibility was 5 miles and the surface wind was light. The pilot intended to reposition his helicopter from an open field onto a nearby trailer. Seconds after taking off, the helicopter's tail rotor contacted a power line that he had not observed. Thereafter, he lost control of the helicopter and it impacted the ground and rolled over. No non-impact related mechanical malfunctions or failures were experienced during the flight.