Bell OH-58, Wilbur-Ellis Co., N543SD: Accident occurred May 21, 2016 in Waitsburg, Walla Walla County, Washington

WILBUR-ELLIS CO: http://registry.faa.gov/N543SD

NTSB Identification: GAA16CA258
14 CFR Part 137: Agricultural
Accident occurred Saturday, May 21, 2016 in Waitsburg, WA
Probable Cause Approval Date: 08/03/2016
Aircraft: BELL OH 58, registration: N543SD
Injuries: 1 Uninjured.

NTSB investigators used data provided by various entities, including, but not limited to, the Federal Aviation Administration and/or the operator and did not travel in support of this investigation to prepare this aircraft accident report.

The pilot reported that he was conducting a low reconnaissance flight prior to helicopter aerial application operations; during the low reconnaissance, the helicopter came in contact with a power line which caught on the left skid. The pilot further reported that, while under tension, a section of the power line "snapped" into the main rotor system resulting in a loss of control. Subsequently, the pilot performed an emergency autorotation to a wheat field which resulted in a hard landing followed by main rotor contact with and consequent separation of the tail boom. 

The fuselage and the tail boom were substantially damaged.

The pilot reported there were no preimpact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation. 

As a safety recommendation, the pilot reported that a more thorough high reconnaissance flight prior to the low reconnaissance flight would have decreased the probability of this accident occurring.

The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
The pilot's failure to maintain clearance from the power line during low reconnaissance flight, which resulted in a power line strike, loss of control, and a subsequent hard landing.