Air accident investigators have discovered issues with a flight recorder on board a helicopter whose blades were ripped off while parked offshore during high winds last year.
The incident took place on the Elgin-Franklin platform during Storm Otto in February 2023, as 100 mile per hour winds battered north-east Scotland.
An Airbus H175 operated by Offshore Helicopter Services UK (OHS) suffered severe damage in high winds, which snapped off four of its five rotor blades.
Video from the platform at the time shows the extent of the damage, and a near miss for two workers beneath the airframe.
In a brief statement marking the anniversary of the incident the Air Accidents Investigation Branch (AAIB) confirmed that a problem with the rotor brake meant the rotor blades had continued to rotate slowly while the aircraft was parked on the platform. This prevented the application of rotor blade tie downs.
Its investigation has so far focused on the cause of the rotor brake failure and the breaking of the blades.
But it has also looked into operational factors, including weather reporting.
In doing so, the AAIB said it had identified “issues with the flight recorder on the aircraft” and is now working with the aircraft and recorder manufacturers to rectify this.
A full report will be published by the department when complete.
What happened during Storm Otto?
Aircraft G-MCSH flew around 130 miles to the Elgin-Franklin complex east of Aberdeen on Friday 17 February 2023, departing just before 7:30am.
The aircraft landed safely but an illuminated tail rotor chip light prevented it from departing for its return journey.
While the chopper was parked on the helipad, storm gusts – which reached in excess of 100mph in the north east – then snapped off three of its five blades close to where they meet the main rotor mast.
Platform operator TotalEnergies later opened up about the incident during a keynote presentation at an Aberdeen HSE conference.
As part of the presentation, TotalEnergies HSE director Mhairi Finnie confirmed that greyed out images on the video were two workers trying to secure the aircraft, who “could have died” as the rotors were then sheared off as powerful winds hit the region.
The oil major said it is opening up in hopes of encouraging others in the industry to move towards transparency in HSE lessons.