The pilot reported that, while hovering the helicopter to park between three stationary helicopters at the airport in Van Nuys, California, the ground crew gave him the signal for a 180° “pedal turn.”
As the helicopter was about to touch down, he felt a shudder in the airframe. He then immediately rolled the throttle closed and completed an emergency shutdown.
Post-accident examination revealed that the tail rotor blades struck the main blades of a stationary helicopter, which likely caused the shudder felt by the pilot.
The helicopter sustained substantial damage to the tail rotor and main rotor systems.
The pilot reported that there were no preaccident mechanical failures or malfunctions with the helicopter that would have precluded normal operation.
Probable cause: The pilot’s failure to maintain clearance from a stationary helicopter during landing. Contributing to the accident was the ground crew’s failure to ensure that the helicopter would clear the stationary helicopter.
NTSB Identification: GAA18CA107
This January 2018 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.