What happened
A flight intended to proceed from Skelle_fteå to Hagfors under visual flight rules (VFR) ended in a fatal accident near Ekfännsberget. The flight initially followed the coastline at a low altitude, passing Sundsvall, before turning directly toward Hagfors. During the flight, the aircraft operated at altitudes ranging from a few hundred to 2,000 feet. As the aircraft passed Leksand, the flight transitioned into night operations.
During the flight, the pilot contacted a colleague via telephone several times, noting poor weather conditions. The pilot expressed uncertainty regarding a potential diversion to Borlänge or Mora Airport, specifically concerning the availability of approach lights at these unmanned locations. At 19:32, while flying at 1,500 feet with a ground speed of 110 knots, the aircraft struck treetops at Ekfännsberget. The impact caused the wings to detach from the fuselage, and the aircraft came to rest upside down. A fire ignited upon impact but burned out before emergency responders reached the site. The pilot sustained fatal injuries.
The investigation
The investigation established that the flight was being conducted under VFR despite the unreliability of the aircraft's attitude indicator and directional gyro. Meteorological analysis by SMHI revealed that at the time of the accident, local cloud bases were below 1,000 feet and visibility was less than 5 kilometers.
Discrepancies in altimeter settings were also identified. While the QNH at the departure airport was 1032 hPa, the primary altimeter was set to 1034 hPa. The investigation found that the pressure difference between the altimeter setting and the local QNH at the accident site meant the altimeter was overstating the aircraft's altitude by approximately 240 feet.
Findings
- The primary cause of the accident was the failure to balance the risks of night VFR flight in low clouds against the desire to reach the destination, which led to the flight continuing despite lacking the legal and practical requirements for VFR operations.
- A contributing factor was the pilot's failure to monitor changes in air pressure, leaving them unaware of the significant drop in QNH between the departure point and the accident location.