Accident Summary
During a climb over rising terrain at 300 to 400 feet above ground level, the pilot observed altimeter and airspeed indications of 8,700 feet and 60 mph. After an additional two minutes of climbing to approximately 10,000 feet (with a density altitude of 12,000 feet), the pilot noticed that rotor RPM was decreasing. He executed a 180-degree right turn and began descending downslope, but the helicopter crash landed at the 8,500-foot level.
Environmental Conditions
The pilot reported winds from the northwest at 5 knots and a temperature of 60°F. Approximately 26 miles northwest at Kailua-Kona, the recorded wind at 1750 was from 030 degrees at 7 knots.
Weight and Balance
Weight and balance records showed the helicopter was loaded to 3,171 lbs, which was 28 lbs below the maximum weight limit.
Performance Analysis
Calculations indicated that a climb rate of 616 ft/min would have been required to maintain a 60 mph climb over the terrain. However, according to the flight manual, at a weight of 3,171 lbs and a temperature of 60°F at 10,000 feet, the helicopter's maximum rate of climb was 450 ft/min. The manual also stated that at an altitude and temperature of 10,000 feet and 60°F, the helicopter could not hover out of ground effect when the gross weight was at or above 2,800 lbs.
Findings
No preimpact mechanical problems were found with the helicopter.