Sikorsky S-92A, G-CHCK
The helicopter was on a public transport flight to offshore platforms in the North Sea and was over water, approximately 65 nm north-east of Aberdeen, when a heavy vibration commenced, which continued until the end of the flight. The crew turned back towards the coast and a successful run-on landing was completed about 30 minutes later. The vibration was found to have been caused by the detachment of a tail rotor blade pivot bearing following a disbond of the bearing retainer from the flexible spar of the blade. Inspections of other S-92 helicopters highlighted other disbonded bearing retainers. Until a final fix is implemented, the helicopter manufacturer has increased the pivot bearing inspection frequency and provided more detailed instructions for inspecting the bearings.
Published 10 December 2014