On 18 February 2009, the crew of Eurocopter AS332 L2 Super Puma attempting to make an approach to a North Sea offshore platform in poor visibility at night lost meaningful visual reference and a sea impact followed. All occupants escaped from the helicopter and were subsequently rescued. The investigation concluded that the accident probably occurred because of the effects of oculogravic and somatogravic illusions combined with both pilots being focused on the platform and not monitoring the flight instruments.