History of the Flight
On 21 June 2005, a Mi-2 helicopter, registration LY-HCS, was chartered to transport five passengers from Heby to Ljusterö to celebrate a passenger's 100th birthday. The pilot, a 50-year-old male with a Hungarian helicopter pilot licence that had expired in May 2003 and a valid Swedish AH licence without type rating, began the flight from his base at Vassunda at 09:20 hours after receiving weather information indicating a southerly wind of 9 knots and a temperature of +21 °C.
Upon arriving at Heby, the pilot surveyed the intended landing site from the air and judged it suitable. He landed the helicopter into the wind near a vacant factory building, stopped the engines, and began boarding. The passengers, including the centenarian, were shown to their seats and instructed to fasten safety belts and don headsets. No further safety instructions were reported.
During the subsequent takeoff, the pilot started the engines, verified normal power output and rotor speed, then lifted vertically, reversed, and began a climb. At approximately three metres above ground, the pilot realised the engines were not delivering full power. Due to the presence of spectators near the takeoff site, he decided not to land immediately and continued forward, veering right. The rotor clipped twigs from a tree and then struck a steel street lighting pole, breaking it. The helicopter descended, contacted the ground with the right landing wheel, rolled over, and came to rest on its right side. A fire broke out in the engine compartment, which the pilot and bystanders fought while assisting passengers in evacuating.
Injuries and Damage
One passenger, the 100-year-old, sustained serious injuries and died three days after the accident. Five other occupants, including the pilot, suffered minor injuries. The helicopter was substantially damaged. Minor damage occurred to a road surface, street lighting, and a nearby house.
Technical Investigation
A technical investigation found foreign material in the fuel injection system of one of the two engines, reducing the fuel flow through that engine by approximately 50%. Based on the manufacturer's estimates, a normally functioning engine could produce 415 hp, while the affected engine was limited to about 180 hp, giving a combined maximum power output of approximately 595 hp.
Cause
The Swedish Accident Investigation Board stated that the accident was caused by a power loss not discovered sufficiently early to interrupt the take-off.