Hughes 369 N298SD accident near Weatherford, Texas

Probable cause

The pilot/mechanic's inadequate postmaintenance and preflight inspections, which resulted in his failure to remove the antitorque pedal lock and a subsequent loss of control during hover operations.

NTSB analysis

The pilot/mechanic stated that, while performing maintenance on the helicopter, he locked the left side antitorque (tail rotor) pedals to keep them out of the way; however, he forgot to unlock them after completing the maintenance. The pilot then conducted a post-maintenance hover check, and, upon increasing collective, the helicopter entered a spin, traveled about 40 feet, and collided with a building and trees.

The pilot stated that there were no preimpact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation, and that the accident was the result of his failure to remove the antitorque pedal lock before flight.

Text from the NTSB. Open the NTSB docket for GAA16LA182 for the full record.