What happened
In the early hours of 3 April 1999, a medical evacuation mission in northern Sweden ended in a helicopter accident near Lake Kamasjaure. The flight, operated by Norrlandsflyg AB, was tasked with transporting two burn victims from a remote fishing site to medical facilities. The crew, consisting of a pilot, a first officer, a doctor, and a nurse, encountered severe weather conditions characterized by heavy blowing snow, ice crystals, and high winds estimated at 45 knots.
To facilitate a landing in the darkness, the crew used the headlights of snowmobiles at the site as a visual reference. During the execution of a right-hand landing circuit, the pilot lost visual contact with these lights due to the intense blowing snow. As the aircraft descended, the pilot misjudged the altitude, leading the Sikorsky S-76A, registration SE-JES, to strike the ground approximately 300 meters from the intended landing spot. The impact caused the aircraft to roll onto its left side. While the crew and passengers survived, the doctor sustained a minor back injury.
The investigation
The Swedish Board of Accident Investigation (SHK) examined the flight history, meteorological data, and the aircraft's mechanical state. The investigation confirmed that the aircraft was airworthy and that no technical malfunctions contributed to the crash. Investigators also reviewed the company's operational procedures and the effectiveness of the emergency response.
Findings
- The primary cause of the accident was the pilot's attempt to land without maintaining sufficient ground references, which led to a critical misjudgment of the aircraft's height over the terrain.
- A significant contributing factor was the lack of established cockpit procedures for two-pilot operations during Visual Flight Rules (VFR) flights within the operator's organization.
- The investigation noted that the NORDRAD weather radar system was not being utilized to its full potential to assist with weather trends.
- Safety concerns were identified regarding cabin safety, specifically that a passenger was not properly secured with a four-point harness at the time of impact.
- There were noted deficiencies in the communication and coordination of the initial alarm process and the activation of ground rescue resources.