What happened
A scheduled domestic flight departing from São Paulo-Congonhas Airport was delayed by eight minutes due to heavy air traffic before receiving takeoff clearance. Shortly after departure, the pilot reported that the number two engine was on fire and declared an intention to return to the airport. During the subsequent maneuvers, the pilot began a left turn and likely feathered the propeller of the affected engine.
While flying the downwind leg toward runway 16, the pilot queried air traffic control regarding visible signs of fire in the number two engine. The tower operators, whose view of that specific engine was obstructed by the fuselage, could not observe any abnormalities. It is believed that during this period, the propeller was unfeathered, causing it to windmill.
As the aircraft passed the tower, it began losing altitude. During the final turn, the plane was at a very low height. The aircraft type entered a stall with a 45-degree bank, striking a house with its nose and left wing before hitting the ground at an elevation of 800 meters. The impact caused the aircraft to complete a 260-degree turn on its left wing. The accident occurred at night in a well-lit, densely populated area. The crash resulted in 37 fatalities (4 crew and 33 passengers) and 13 injuries.
Findings
Investigations revealed that an overheat alarm triggered immediately after takeoff for unknown reasons. Believing the engine was on fire, the pilot feathered the propeller. However, when the propeller was unfeathered during the downwind leg, the fuel shut-off valve remained closed, causing the engine to windmill. Despite the remaining engine operating at takeoff power, the aircraft could not maintain its altitude.
As the aircraft approached the final turn, it was at a critically low altitude. The pilot likely attempted to pull up the nose to avoid nearby buildings, which induced a stall. It is also noted that a crew member may have deployed the flaps during this sequence. The investigation concluded that improper procedure regarding the unfeathering of the engine was the primary cause, and a potential material failure leading to overheating was a secondary factor.