No fatalities

12 Apr 2019: Bell 206 L4 — Florida Keys Mosquito Control District — Big Pine, FL

Big Pine, FL, United States

On 12 Apr 2019, a Bell 206 L4 operated by Florida Keys Mosquito Control District was involved in an aviation accident near Big Pine, FL. No fatalities were reported. Investigators recorded the probable cause as: The pilot's failure to maintain helicopter control while it was being reloaded with the rotors turning in gusting wind conditions, which resulted in a rotor strike with ground equipment. This summary draws on records from NTSB; 12 related events involving the same aircraft type or operator are linked below.

SourcesNTSBPrimary reportUpdated 1778583330Data APIEditorial standards

A helicopter sustained substantial damage when a main rotor blade struck an autoloader boom arm after the pilot exited the aircraft during loading. No preaccident mechanical failures were reported.

Incident Overview

A helicopter pilot reported that, after completing the fourth aerial application flight of the day, he landed the helicopter and positioned it near an autoloader boom truck. He reduced engine power to flight idle, and the ground crew began the loading process. The pilot verified that the collective position was full down and set the cyclic friction to ON before exiting the helicopter to stretch, while maintaining one hand on the cyclic.

Sequence of Events

Immediately after exiting, while standing next to the helicopter, the pilot heard two loud bangs. He quickly boarded the helicopter, the ground crew secured the boom arm, and the pilot shut down the engine. No injuries or other damage were reported.

Inspection and Findings

An examination by the operator's maintenance personnel determined that a main rotor blade had struck the boom arm. The main rotor blades were found to be beyond the repair limitations specified by the manufacturer. The helicopter sustained substantial damage to the main rotor blades.

Contributing Factors

The director of aerial operations reported that there were no preaccident mechanical failures or malfunctions with the helicopter that would have precluded normal operation. Additionally, the director noted that at the accident site, the wind was from 130 degrees at 11 knots, gusting to 19 knots. The helicopter was oriented with a southbound heading.

Contributing factors

PilotEffect on operation