Aeroflot-Nord flight 821 took off from Moscow’s Sheremetyevo Airport at 21:13 hours on a domestic flight to Perm, Russia. Contact with the flight was lost while the airplane was at 3600 feet in “difficult weather conditions”, according to Aeroflot officials. The plane came down on the outskirts of the city, hitting the ground just a few hundred yards from small wooden houses and apartment buildings. Investigation revealed that the pilot lost spatial orientation during the night-time approach through clouds. This led to a banking of the plane onto its left wing, and its entering into an intensive descent and collision with the ground. The pilot was not familiar with the attitude indicator (ADI) used on Western jets, compared to those of Russian jets. Also, an unspecified amount of alcohol was detected in the pilot’s body, and he was overworked. The immediate cause of the accident was spatial disorientation of the crew, especially the Captain who was the pilot flying at the final stage of the flight, which led to the left flip-over, a steep descent and the crash of the aircraft. The spatial disorientation was experienced during the night time operation in clouds, with both autopilot and autothrottle disengaged. Contributing to the development of the spatial disorientation and failure to recover from it was a lack of proficiency in aircraft handling, crew resource management and of skills associated with upset recovery using “western”-type attitude indications that are found on foreign and modern Russian-made aircraft. This type of indication differs from the one used on aircraft types previously flown by the crew (Tupolev 134, Antonov 2). The systemic cause of the accident was insufficient management by the airline of flight and maintenance operations of the Boeing 737 type of aircraft. These deficiencies in the aircraft maintenance also revealed through safety inspections conducted by the Russian Transport Oversight Authority and the Russian CAA after the accident. Deficiencies in the aircraft maintenance led to a situation when flights were performed for a long time with a throttle stagger [difference in trim of right and left engines, when matching throttle position leads to a split in engine thrust while matching thrust leads to different throttle position] that exceeded the limitations in the AMM and when the maintenance staff did not follow the AMM recommended troubleshooting procedures. The need to manage the throttle stagger during the approach increased crew workload. The forensic medical examination performed in the State Healthcare Center of Special Status “Perm Regional Forensic Expertise Bureau” confirmed the presence of ethyl alcohol in the Captain’s body before his death. The captain’s recent work schedule during the time period before the accident was conducive to fatigue and did not comply with national regulations.