VARIG - Viação Aérea Rio Grandense

A. Human Factor
1) Physiological aspect - Did not contribute to the accident.
2) Psychological aspect - The following psychological variables contributed to the accident:
a) Misleading perception - In the reading of the plan and incorrect heading insertion by the commander.
b) Reinforcement - In the reading and incorrect heading insertion by the co-pilot and heading conference placed by the commander.
c) Marginal attention and level of attention - The non-recognition of conditions that would mean being far from the objective: request for "VHF bridge" when other aircraft were talking normally with the Control; "reception" of commercial stations, and non-receipt of destination NDB, etc.
d) Predisposition - Maintaining the urge to go to the established objective (Belém).
e) Predisposition duration - Maintenance of FL040 for a long time.
f) Reinforcement of predisposition - Reception of boundaries when selecting Belem's radio frequencies.
g) Attention Fixing - Permanent search for headings, radio contacts or river contours, as an alternative, to reach the fixed goal.
h) Blocks - Delays in identifying the initial headings error and plotting itself in navigation.
i) Geographical position error.
B. Material Factor - Did not contribute to the accident.
C. Operational Factor
1) Poor supervision - Inadequate graphical representation of the Computer Flight Plan.
2) Poor cockpit coordination - No supervision of cockpit activities. Actions were not supervised, but imitated.
3) Poor support staff - Lack of radio contact by the operator's Flight Coordination with the aircraft in flight, after the significant landing delay in Belém, thus breaking the chain of events of the accident.
4) Pilot aspect characterized by environmental influence - Difficulties of visualization due to sunset and dry fog: Radio aid markings received from great distances, originating from the ionospheric propagation of electromagnetic waves.
5) Pilot aspect characterized by poor planning - Lack of route letters to cross the flight plan information.
6) Pilot aspect characterized by poor judgment - Inadequate evaluation and use of radio-navigation equipment, resulting in the pursuit of markings without causing tuning and identification.
7) Pilot aspect characterized by other operational factors - Operational doctrine firming.

It was determined that the fire alarm on engine n°1 also sounded during the first leg from Rio to Abidjan. A check was conducted by Air Afrique technicians who confirmed this was a false alarm. During the last turn completed by a moonless night and without any visual contacts with the ground, the pilot-in-command lost control of the airplane after suffering a spatial disorientation.

Due to lack of evidences as the wreckage was not found, the exact cause of the accident could not be determined. However, it was reported that the crew did not send any distress call and it is believed that the accident may have been caused by a sudden and accidental decompression of the cabin.

A fire which appears to have started in the washbasin unit of the aft right toilet. It was detected because smoke had entered the adjacent left toilet. The fire may have been started by an electrical fault or by the carelessness of a passenger. The difficulty in locating the fire made the actions of cabin personnel ineffective. The flight crew did not have the facilities to intervene usefully from the cockpit against the spread of the fire and the invasion of smoke. The lack of visibility in the cockpit prompted the crew to decided on a forced landing. At the time of touch-down the fire was confined to the area of the aft toilets. The occupants of the passenger cabin were poisoned, to varying degrees by carbon monoxide and other combustion products.

On short final, with speed brake lever at 45° and inboard spoilers deactivated, the crew noted that the spoiler switch cover was open. It is believed that the copilot mistakenly closed the spoiler switch cover and thus activated the inboard spoiler, causing the aircraft to pitch down and to crash into the sea.

The takeoff was performed with a simulated failure of the right engine. Incorrect procedure used by the instructor by simulating the engine failure below V1 and attempting to unstick the aircraft below minimum control speed.