What happened
On April 27, 2013, a Eurocopter AS 350 B3, registration LN-OVO, was performing a passenger transport mission near the Røldal ski center in Håradalen, Norway. The flight, operated by Fonnafly AS, was intended to transport personnel and equipment for the Røldal Freeride Challenge.
While flying at a low altitude of approximately 100 to 200 feet above the ground, the pilot decided to perform a 360-degree reconnaissance maneuver to inspect a potential landing site. The pilot initiated the turn by pulling the nose up sharply, causing a rapid decrease in airspeed and a steep climb. As the aircraft entered a left-hand turn, the pilot noticed high-voltage power lines to the right and attempted an even sharper turn to avoid them. This aggressive maneuvering resulted in a significant loss of altitude. The aircraft eventually struck the ground, causing the tail boom to be severed by the main rotor blades. Despite the impact, all 5 occupants evacuated the aircraft with no serious injuries, though one passenger sustained a laceration to the leg.
The investigation
The Norwegian Safety Investigation Authority (NSIA) examined flight footage provided by a passenger, engine data from the Vehicle and Engine Multifunction Display (VEMD), and fuel samples. The investigation also included police breathalyzer tests administered to the pilot following the accident.
Technical analysis of the VEMD revealed that the engine torque had briefly reached 114% during the maneuver, indicating a momentary overstress of the engine. Fuel analysis showed minor particulate matter, but investigators determined this was not a contributing factor to the crash. The investigation also noted that the pilot had only used a lap belt rather than the full shoulder harness, which contributed to him striking the cockpit interior during the impact.
Findings
- The primary cause of the accident was a miscalculation during an aggressive maneuver at low altitude.
- The pilot's decision to perform a sharp, high-load turn at a very low height led to an unrecoverable loss of altitude.
- Post-accident breathalyzer tests indicated the pilot's blood alcohol content was above the legal limit for aviation, suggesting potential alcohol impairment which may have degraded decision-making and physical performance.
- The pilot's attempt to avoid power lines by increasing the sharpness of the turn exacerbated the descent.
- The investigation could not rule out aerodynamic phenomena such as "settling" or the aircraft entering its own rotor wake due to the intensity of the turn.
Safety action
- The NSIA noted that the pilot's behavior was characteristic of a broader safety challenge in domestic helicopter operations, where pilots may engage in risky maneuvers when unmonitored.
- The authority suggested that the installation of flight monitoring systems (such as GPS and flight data recorders) in light helicopters could provide a disciplinary effect and help prevent such high-risk behavior.