The cause for the crash of Viasa Flight 897 was never determined by either Portuguese or Dutch authorities. The official report out of Portugal concluded "Notwithstanding a very thorough, time-consuming investigation, in which many authorities and experts co-operated, it was not possible to establish a probable cause of the accident." The Netherlands, as state of registry for the aircraft, commented: "Though there are no direct indications in this respect, the Board regards it as possible that the accident was due to the pilot or pilots being misled by
instrument failure, in particular of the
artificial horizon, or to the pilot having been distracted, so that a serious deviation from the normal flight path was not discovered in time." ==Legacy==