The aircraft was using instrument flight rules (IFR) and Torghatten was covered in fog. The visibility was within the permitted range of IFR. The commission found five errors on Widerøe's maps which could have influenced the accident. This included a formulation which gave the impression that DMR was not in use; a closed Torget marker beacon was still on the maps; a vertical flight plan from Lekan was not included; the height limitations in the accident area were noted through comments rather than through a graphical presentation; and confusion as to when the timing of final approach should start. The commission also criticized the airline for its checklists instructing the pilots to one of VHF channels to the company frequency during descent, at a time when non-safety-related communication is unwanted.