On December 26, 2000, about 1630 Atlantic standard time, a Robinson R-22 Beta, N195HC, registered to and operated by Copters Incorporated, as a Title 14 CFR Part 91 instructional flight, experienced a hard landing in an open field in Ciales, Puerto Rico. Visual meteorological conditions prevailed, and no flight plan was filed. The helicopter incurred substantial damage, and the commercial-rated flight instructor and one student were not injured. The flight originated from Isla Grande, the same day, about 1545. The flight instructor stated that he and the student had been performing autorotation landings in an open field, and they had done three or four autorotation landings with both him and the student at the controls. The instructor further stated that during the last autorotation, when power was required by him to affect the recovery, the engine did not produce enough power, and the helicopter landed hard. He stated that when the helicopter impacted, the skids paralleled the ground, and the main rotor hit the tail boom, separating half of it from the rest of the helicopter. According to the instructor, the autorotation was started at no less than 500 feet above ground level, and during the maneuver airspeed and rotor RPMs were kept at appropriate settings. On December 28, 2000, an FAA inspector and an FAA licensed company mechanic examined the accident helicopter, and performed a static power test on the engine. According to the inspector, the static test was performed with the engine operating at idle, and at full power for about 15 minutes. The inspector stated that during the static test no abnormalities were observed. In addition, the inspector further stated that they checked the engine fuel filter and found no evidence of fuel contamination.