Primary finding
Probable cause
The pilot's failure to correct a settling-with-power condition during a helicopter landing flare/touchdown, resulting in a hard landing and roll over.
Investigator assessment
Analysis narrative
The commercial certificated pilot departed a survey camp in a high skid-equipped helicopter, on an air taxi flight to survey potential exploration sites. The director of operations said the pilot told him that he was flying about 70 feet above the ground at 50 knots when he began a descending 180 degree left turn to land in an area of flat open tundra. The pilot indicated the airspeed decreased during the turn, and the helicopter shuddered and developed a high rate of descent. The pilot applied collective pitch and power, but the rate of descent increased. The right landing gear skid contacted the ground, and the helicopter rolled onto its right side. The pilot told the director of operations that the wind conditions were about 8 knots from the northeast.
Source record
Factual narrative
On July 23, 2002, about 1515 Alaska daylight time, a high skid-equipped Messerschmitt Bolkow Blohm (MBB) BO-105S helicopter, N491HL, sustained substantial damage when it collided with tundra-covered ground after developing a high rate of descent during the landing flare in a remote area, about 70 miles south-southwest of Deadhorse, Alaska. The helicopter was being operated as a visual flight rules (VFR) domestic on-demand passenger flight under Title 14, CFR Part 135, when the accident occurred. The helicopter was operated by Air Logistics of Alaska Inc., Fairbanks, Alaska. The commercial certificated pilot, and the sole passenger, were not injured. Visual meteorological conditions prevailed. A VFR flight plan was filed. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC), on July 24, the director of operations for the operator reported the pilot departed a survey camp area known as Happy Valley, located about 20 miles south of Deadhorse along the Sagavanirktok River, on a flight to survey potential exploration sites. The director of operations said the pilot told him that he was flying about 70 feet above the ground at 50 knots. The pilot then began a descending 180 degree left turn to land in an area of flat open tundra. During the turn, the pilot began decreasing the airspeed. The helicopter shuddered and developed a high rate of descent. The pilot applied collective pitch and power, but the rate of descent increased. The right landing gear skid contacted the ground, and the helicopter rolled onto its right side. The pilot told the director of operations that the wind conditions were about 8 knots from the northeast.