Accident Overview
On 27 January 2010, at approximately 1423 local time, a Robinson R44 Astro helicopter (registration LN-OCV) operated by Midtnorsk Helikopterservice AS crashed into the sea about 250 meters offshore near Horten, Norway. The helicopter was part of a loose formation with another R44, flying from Melsomvik toward Oslo. All four persons on board were fatally injured.
Flight and Accident Sequence
The two helicopters were flying together with the more experienced pilot leading. Near Horten, they encountered a belt of fog that prevented further flight along the planned route. Airspeed was reduced and the formation came nearly to a halt while the pilots considered an alternative course of action. Witnesses observed the rearmost helicopter (LN-OCV) execute rapid, uncontrolled pitch and roll movements. It then nosed down, turned right, and entered a descending spiral until it struck the partially frozen sea surface and sank.
Investigation Findings
The investigation by the Accident Investigation Board Norway (AIBN) revealed that multiple factors contributed to the loss of control. The helicopter was operated above its maximum allowable mass and with its center of gravity forward of the forward limit. Power reserve was likely minimal. The situation was aggravated by the need to stop and hover in poor visibility while maintaining formation with another aircraft. The pilot, who was relatively inexperienced, lost control of the helicopter under these conditions. The AIBN determined that once control was lost, it could not be regained given the circumstances.
Further, the investigation identified that the operator had outsourced control of operations at a non-approved base to a freelance pilot who also marketed helicopter rides. The Norwegian Civil Aviation Authority (N-CAA) had repeatedly noted the company's failure to apply for approval for this base and had issued findings regarding mission authorization and pilot training. However, these deficiencies were not adequately rectified.
Probable Cause
The AIBN stated that the accident resulted from a combination of factors leading to the inexperienced pilot losing control: stopping and hovering in poor visibility while part of a formation, the helicopter exceeding its maximum mass and having its center of gravity forward of limits, and minimal power reserve. Under the prevailing conditions, recovery was impossible.