What happened
On 22 February 2008, a Eurocopter AS332L2 Super Puma, registration G-REDM, was performing a commercial passenger flight from the ‘Bruce’ offshore platform to Aberdeen. While cruising at 2,000 feet through a line of rain showers, the crew observed a bright flash at the rotor tip accompanied by a loud bang.
Following the strike, the crew evaluated their options. In accordance with safety checklists, they considered diverting to the nearest available offshore platform to land as soon as possible. However, because the nearest platforms were experiencing winds exceeding 50 knots and other directions presented unfavorable weather, the crew elected to continue the flight to Aberdeen. The aircraft maintained normal flight characteristics and landed safely without any loss of systems.
The investigation
Post-flight inspections of G-REDM revealed several areas of damage caused by the electrical discharge. The investigation identified arcing damage on the leading edge anti-erosion strips of the main rotor blades, broken bonding leads, and damaged trim tabs. Furthermore, high energy tracking was found on two pitch link ball joints and one main rotor servo upper ball joint.
One of the four main rotor blades was found to be damaged beyond repairable limits, though the remaining three were serviceable. The investigation also reviewed lightning detection data from the area. While specialist equipment recorded electrical discharges near the time of the event, none were located within 60 km of the aircraft, suggesting the strike was likely an inter-cloud or intra-cloud event triggered by the aircraft's presence.
Findings
- The aircraft sustained damage to the main rotor blades, including broken bonding leads and arcing on anti-erosion strips.
- The strike was likely an inter-cloud or intra-cloud lightning event.
- There was no loss of aircraft systems or impact on flight handling following the strike.