Bell 206B N4237M accident near Wells, Nevada

Probable cause

The pilot's failure to maintain clearance from an obstacle while maneuvering at a low altitude.

NTSB analysis

The pilot reported that he was flying the helicopter to specific locations within hilly sage and brush covered terrain in order for his passenger to set mining claim stakes at various intervals. Movement between the stake locations was typically conducted at a low altitude. The pilot stated that as he flew the helicopter over the crest of a hill, he felt the helicopter shudder and vibrate, and he initiated an autorotation to an open field. After what he described as an uneventful landing, the pilot noticed that the tailrotor and its drive shaft were damaged. The pilot further reported that he noticed a bush with several broken branches that was located along the helicopter's flight path, and he believed that the tailrotor struck that bush while he was maneuvering. The pilot reported no preimpact mechanical malfunctions or failures with the helicopter that would have precluded normal operation.

Text from the NTSB. Open the NTSB docket for WPR13CA204 for the full record.