Bell 206 N9913K accident near Terra Alta, West Virginia

Probable cause

The pilot’s inability to maneuver the helicopter for recovery after experiencing a strong, unanticipated tailwind in a confined operating area, which resulted in a descent and subsequent impact with terrain.

NTSB analysis

The pilot was operating the helicopter near maximum gross weight about 400 ft above ground level, following the terrain for an aerial observation flight. About 10 seconds into a descent, over a hilltop toward the next power transmission line, the helicopter encountered a strong tailwind. Noting a loss of airspeed, the pilot lowered the collective to gain airspeed; however, the helicopter continued to slow and descend. The pilot further lowered the collective and pushed the cyclic forward, but this was ineffective in increasing the helicopter’s airspeed. Given the low operating profile in the confined surveying location between power transmission lines and trees, the pilot did not have adequate space to compensate for the tailwind condition or turn the helicopter into the wind. Consequently, the helicopter continued to descend until it impacted the ground.

The pilot reported that there were no preimpact mechanical malfunctions or failures of the helicopter that would have precluded normal operation and stated (and a review of meteorological data confirmed) that the stronger than anticipated tailwinds arrived before the forecasted time.

Text from the NTSB. Open the NTSB docket for ERA23LA307 for the full record.