What happened
On 21 June 2005, a Mi-2 helicopter, registration LY-HCS, was engaged in a private flight to transport five passengers for a 100th birthday celebration near Heby, Sweden. After selecting a suitable landing site near a vacant factory, the pilot initiated the takeoff procedure.
As the aircraft reached an altitude of approximately three meters, the pilot noticed that the engines were failing to provide sufficient power. To avoid endangering spectators gathered near the takeoff area, the pilot attempted to continue the flight rather than performing an immediate landing. During this maneuver, the helicopter veered to the right, causing the main rotor to strike tree branches and subsequently impact a steel street lighting pole. The impact caused the rotor to break apart, and the helicopter rolled onto its side. A fire broke out in the engine compartment following the crash. While the pilot and passengers were evacuated, one passenger sustained serious injuries and passed away three days later. Five other passengers sustained minor injuries.
The investigation
The Swedish Accident Investigation Authority (SHK) conducted a technical examination of the aircraft's engines and fuel systems. The investigation focused on the performance of the engines during the critical takeoff phase and the impact of the surrounding environment on the pilot's decision-making. Investigators also reviewed the pilot's licensing status and the aircraft's airworthiness documentation.
Findings
- A technical fault in one of the engines significantly reduced available power. Specifically, corrosion in the fuel injection nozzle caused a partial obstruction, reducing the fuel flow through that engine by approximately 50%.
- The reduction in power meant the total available thrust was insufficient to maintain a steep climb over nearby obstacles.
- The pilot's decision to continue the flight instead of interrupting the takeoff was influenced by the presence of bystanders near the takeoff site.
- The pilot was flying with an expired Hungarian license that was in the process of being renewed.