Narrative:Flight WF710 took off from Trondheim (TRD) at 19:23 on a domestic light to Namsos (OSY), Brønnøysund (BNN), Sandnessjøen (SSJ) and Bodø Airport (BOO).
The flight to Namsos was uneventful. The flight took off at 20:07 and contacted Trondheim ACC six minutes later, stating that they were climbing from FL70 to FL90. At 20:20 the crew began their descent for Brønnøysund and switched frequencies to Brønnøysund AFIS.
Weather reported at Brønnøysund was: wind 220°/05 kts, visibility 9 km, 3/8 stratus at 600 feet and 6/8 at 1000 feet, temperature +6 C, QNH 1022 MB.
The crew executed a VOR/DME approach to Brønnøysund's runway 04, and it would circle for landing on runway 22. The crew left the prescribed altitude 4 NM early. The aircraft descended until it flew into the Torghatten hillside at 560 feet.
A retired police officer reported in July 2013 that a passenger had taken a mobile phone on board. The police officer disembarked the plane at Namsos, a stop-over and reported that the passenger with the mobile phone was seated in the cockpit's jump-seat.
After the accident, he reported this fact to the Joint Rescue Coordination Centre (JRCC). After reading the investigation report during the 25th anniversary of the accident, he noticed that there was no mention of the mobile phone.
NMT 450 network-based mobiles at the time were fitted with a 15-watt transmitter and a powerful battery which could lead to disruption in electronic equipment.
The AIB said it would investigate if electronic interference from the mobile phone may have affected the flight instruments.
PROBABLE CAUSE: "Havariets årsak var at siste del av innflygingen ble påbegynt omlag 4 NM for tidlig. Derved kom flyet under høyden for sikker terrengklaring og kolliderte ned stigende terreng. Kommisjonen kan ikke angi noen sikker grunn til at nedstigningen ble iverksatt så tidlig. Det er imidlertid godtgjort at besetningen ikke gjennomførte en forskriftsmessig flyging, idet den unnlot fullt ut å forholde seg til gjeldende bestemmelser og prosedyrer som forutsatt. Det har i denne forbindelse hos kommisjonen festnet seg den oppfatning at selskapets egenkontroll ikke tilstrekkelig hadde fanget opp visse svakheter knyttet til det foreliggende grunnlagsmateriale og den praksis som forekom. Dette kan ha bevirket at holdningen overfor en sunn 'Cockpit' disiplin og den gjensidige kontroll mellom besetningsmedlemmene var blitt undergravet. Navigeringen av fartøyet ble dermed ikke fulgt opp og tilfredsstillende gjennomført."
Controlled Flight Into Terrain (CFIT) - Mountain
Official accident investigation report
This map shows the airport of departure and the intended destination of the flight. The line between the airports does not
display the exact flight path.
Distance from Namsos Airport to Brønnøysund Airport as the crow flies is 114 km (71 miles).