DFW05CA168

The 724-hour flight instructor reported that the student pilot initiated a planned power-recovery 180-degree autorotation to a plowed field. As the student attempted to recover with power, approximately 20-50 feet above ground level, the instructor noticed "that the engine rpm needle was not coming up to meet the rotor rpm needle." The instructor immediately attempted to "roll maximum throttle on," but realized the throttle would not move, and took control of the helicopter. The student told the instructor that the throttle was stuck. However, the instructor stated the throttle seemed "stuck because it was all the way open." Subsequently, the helicopter contacted the ground and the right skid "dug into the ground," as the helicopter rolled over and came to rest on its right side. The instructor stated that the engine was not running and the throttle was wide open when he took the controls. No mechanical anomolies were noted with the engine or the airframe. The reason for the loss of engine power was undetermined.

On June 22, 2005, approximately 1945 central daylight time, a single-engine Hughes 269C helicopter, N7487F, registered to DD Leasing of McGregor, Texas and operated by Brazos Helicopters of Bruceville, Texas, was substantially damaged during a practice autorotation after a reported loss of engine power near Bruceville, Texas. The flight instructor and the private pilot receiving instruction, were not injured. Visual meteorological conditions prevailed throughout the area, and a flight plan was not filed for the instructional flight conducted under 14 Code of Federal Regulations Part 91. The local flight departed from a private heliport near Bruceville, Texas, approximately 1910.

According to information provided to the NTSB by the 724-hour flight instructor, the student pilot initiated a practice 180-degree autorotation to a plowed field from an altitude of 700 feet above ground level. The flight instructor added that the practice autorotation was intended to be terminated by a "power recovery," which is a typical recovery technique utilized in primary helicopter instruction. The instructor reported that, "at the time to commence a power recovery," while at approximately 20-50 feet above ground level, he noticed "the engine rpm needle was not coming up to meet the rotor rpm needle." The instructor immediately attempted to "roll maximum throttle on," but realized the throttle would not move, and took control of the helicopter. The student pilot told the instructor that the throttle was stuck. However, the instructor stated the throttle seemed "stuck because it was all the way open."

Subsequently, the helicopter contacted the ground and the right skid "dug into the soft ground." The helicopter rolled over coming to rest on its right side. The instructor stated that the engine was not running and the throttle was wide open when he took over the controls of the helicopter.

Examination of the helicopter by a Federal Aviation Administration (FAA) safety inspector, who responded to the accident site, revealed that the tail boom was severed, the main rotor blades were damaged, and the forward section of the right landing skid was separated from the landing gear crosstube assembly. Usable fuel was observed in the fuel tank and examination of the Lycoming HIO-360 engine revealed no mechanical anomalies. The throttle control cable was found connected and moved freely when manipulated by hand.

At 1951, the automated surface observing system (ASOS) at the Waco Regional Airport, near Waco, Texas, located approximately 15 miles north of the accident site reported wind from 110 degrees at 4 knots, visibility 10 statute miles, clear sky, temperature 86 degrees Fahrenheit, dew point 59 degrees Fahrenheit, and an altimeter setting of 30.06 inches of Mercury.