Incident Overview
On 12 May 2016, at approximately 10:55 local time, a Bell 206 Jet Ranger B3 helicopter was conducting a flight to extend the pilot's rating, accompanied by an examiner from the Polish Civil Aviation Authority (ULC). The flight originated and was scheduled to return to EPWL Wielkie Lniska airfield near Grudziądz.
During the approach to landing, the helicopter encountered strong turbulence. The pilots felt a sudden "swing" of the main rotor, followed by vibrations throughout the aircraft. In response, the crew altered the flight parameters, and the vibrations ceased. The helicopter landed safely at the airfield.
Post-Flight Actions
After landing, the pilot informed the maintenance manager about the incident. The helicopter was grounded pending inspection. Maintenance personnel examined the main rotor blades, swashplate, tail boom, tail rotor gearbox, and tail rotor. No abnormalities or defects were found. Consequently, the helicopter was returned to service.
Probable Cause
The investigation determined that the probable cause of the incident was improper use of flight controls in conditions of strong turbulence.
Safety Recommendations
The Polish State Commission on Aircraft Accident Investigation (PKBWL) did not issue any safety recommendations. The operator informed its flight personnel about the incident as a preventive measure.