NTSB Factual Report

On April 20, 2002, approximately 1500 mountain daylight time, an Enstrom F-28C helicopter, N51769, collided with terrain just after liftoff from an off-airport site near Hot Springs, Montana. The commercial pilot and his two passengers were not injured, but the aircraft, which is owned and operated by the pilot, sustained substantial damage. The local 14 CFR, Part 91 pleasure flight was being operated in visual meteorological conditions. No flight plan had been filed. There was no report of an ELT activation.

According to the pilot, when he and his passengers boarded the helicopter, the winds were almost nonexistent. But, by the time he was ready to lift off, the winds were variable at about ten knots. In a telephone interview with the Investigator-In-Charge (IIC), the pilot said that right after liftoff, just as the helicopter was starting to move forward, the wind shifted from a headwind to a tailwind gust. Although he attempted to compensate for the change in relative wind, the pilot was unsuccessful, and the helicopter impacted the terrain with sufficient force to result in the main rotor coming in contact with the tail boom. According to the fuel and occupant weights provided by the pilot, the aircraft was being operated within 25 pounds of its certified maximum gross weight.

NTSB Probable Cause

The pilot's failure to adequately compensate for unfavorable wind conditions. Factors include unfavorable/shifting winds, and a tailwind gust.