Accident Overview
On September 18, 2015, at approximately 0815 Pacific daylight time, a Schweizer 269C helicopter, registration N290R, sustained substantial damage during an off-field landing near Forest Grove, Oregon. The helicopter was operated by Oregon Roses Inc. under 14 CFR Part 91. The commercial pilot, the sole occupant, sustained minor injuries. Visual meteorological conditions prevailed, and no flight plan was filed for the positioning flight, which originated from a private helipad at about 0814.
The pilot reported that during low-altitude cruise to a nearby landing site for planned chemical spray, the engine lost power and the helicopter began losing altitude. At the time, the helicopter was flying at about 40 knots and approximately 55 feet above ground level. During the subsequent auto-rotation, the helicopter struck wires near the ground, resulting in a dynamic rollover. The helicopter came to rest on its left side, nearly inverted.
Postaccident Examination
A postaccident examination by a Federal Aviation Administration (FAA) inspector revealed substantial damage to the main rotor blades and tail boom. The helicopter was recovered to a secure local storage facility for further examination.
The National Transportation Safety Board investigator-in-charge, an FAA inspector, a Sikorsky investigator, and a certified Airframe and Powerplant (A&P) mechanic conducted a further examination. No evidence of internal damage to the engine or its accessories was found. The oil dipstick reading indicated 6 quarts. The exhaust remained attached and was intact. Continuity of all engine controls was established. Lower spark plugs were removed and examined; all electrodes exhibited normal wear signatures compared to the Champion Check-A-Plug comparison chart. The crankshaft was rotated by hand, and compression was obtained on all cylinders. It was determined that an engine run could be safely accomplished.
The engine was subsequently test run and functioned normally at a low power setting. When the magnetos were switched from left to right, the corresponding RPM drop was observed. The Sikorsky investigator and the certified A&P mechanic stated that the engine ran smoothly and that no anomalies were observed. The engine run was performed at a low power setting only due to concerns about damage to the mast support structure and the helicopter's overall stability after removal of the main rotor blades and tail boom.
Systems Examination
The helicopter's main transmission, gearboxes, drive shafts, and rotor heads were examined. No anomalies were noted except for the tail rotor drive shaft, which was separated by a main rotor blade strike just aft of the vertical stabilizer mounting point. Tail rotor drive continuity was established to the point where the tail boom was separated, and from the separation point to the tail rotor gearbox. Flight control continuity was established with the cyclic and collective. The electric cyclic trim system was operated during the examination with no anomalies noted.
Fuel System Examination
Examination of the fuel system revealed that the helicopter was equipped with a 49-gallon fuel tank. The tank sustained damage to the aft, outboard portion but remained intact, with no loss of fuel. The fuel screen was removed, and fuel was present in the screen housing. The screen was observed to be clean of debris. Fuel samples from the storage tank and helicopter were taken and later tested by the FAA using water detection paste, with negative results.
Maintenance Records
A review of the helicopter's maintenance records revealed that the engine and airframe underwent their most recent annual inspection on September 8, 2015, at an airframe total time of 2,050.9 hours. The time since overhaul of the engine was 494.2 hours.