Dehavilland DHC-6-300 N241SA accident near Boulder City, Nevada

Probable cause

A loss of directional control during the landing roll in gusting crosswind conditions.

NTSB analysis

The crew of the Part 135 sightseeing flight was returning from a tour when they encountered strong, gusting crosswinds during the landing approach at velocities approaching the airplane’s maximum demonstrated crosswind component (a value which the airplane’s flight manual stated is not considered limiting). The crew elected to continue the approach and land on the airport’s longest and widest runway. The captain, who was the pilot flying, configured the airplane with reduced flaps in accordance with the manufacturer’s crosswind landing recommendations. Both pilots stated that the approach and touchdown were stable and on the centerline; however, shortly after touchdown, a gust or shift in wind direction caused the airplane to veer left.

Despite the captain’s corrective control inputs, the airplane departed the runway and struck a runway distance marker, resulting in substantial structural damage. Examination revealed no mechanical anomalies with the flight controls or brakes; neither the crew nor passengers were injured.

Review of recorded weather information indicated that the wind conditions encountered during landing were slightly higher than forecast and higher than that reported during departure. Weather at nearby airports showed even higher wind velocities, which would have resulted in comparable or greater crosswind components for their runways. Given that all nearby airports were affected by similar conditions, a diversion was unlikely to provide improved landing conditions.

Text from the NTSB. Open the NTSB docket for WPR25LA038 for the full record.