Report concerning the air accident in Follebu, Gausdal municipality, Innlandet county, Norway on 1 August 2019 involving Hughes Helicopters Inc. 369D, SE-JVJ operated by First European Aviation Company Sp. z.o.o.
The helicopter carried out line inspection using laser scanning and aerial photography. Approximately 52 minutes into the flight the commander became aware of abnormal vibrations in the helicopter. The vibrations increased in intensity and the commander decided to make an emergency landing on a field. During the last phase of the approach, for approx. 3 meter altitude, the crew heard a bang and the helicopter lost all power. The commander lost control of the helicopter which landed hard. The right skid collapsed, the horizontal stabiliser, and all five main rotor blades were in contact with the ground and were substantially damaged. The crew was uninjured. The powerloss was caused by a fracture in the main gearbox input pinion. The pinion fracture was caused by fatigue. It has not been possible to determine what caused the fatigue.
Regardless of the cause, the NSIA is of the opinion that some of the maintenance work on the main gearbox had not been performed in accordance with the expected standard. Moreover, the NSIA finds that the continuing airworthiness management and the submitted maintenance documentation were inadequate.
|Location||Follebu, Gausdal municipality, Norway|
|Aircraft||McDonnell Douglas MD-369|
|Operator||First European Aviation Company Sp. (FEAC), Poland|
|Type of occurrence||Accident|
|Type of operation||Commercial, other|
|Category of operation||Light, helicopter (<= 2 250kg)|
|Aircraft category||Helicopter, Single-engine, Turboprop/turboshaft|
|FIR/AOR||ENOS (Oslo ATCC)|