What happened
On February 27, 1975, at 18:23 local time, an EMB 110, registration PP-SBE, operated by VASP, departed from runway 34 at São Paulo airport bound for Bauru. Shortly after takeoff, the aircraft performed a short straight flight during which witnesses observed abnormal engine operation in one of the two turbines, though the specific engine could not be definitively identified.
The crew subsequently initiated a left-hand turn while losing altitude. Approximately 1,50 and meters from the threshold of runway 16, the aircraft entered an inverted position and collided with the rear of four residential buildings. The impact resulted in a post-crash fire. The accident resulted in four fatalities, including the two crew members and two passengers.
The investigation
CENIPA established several sub-committees to examine the structural, powerplant, and flap systems. The investigation focused on the engine performance, the condition of the fuel control units (FCU), and the flight control surfaces.
Investigators examined the left and right nacelles, finding that the left nacelle showed upward and lateral force consistent with the aircraft's inverted impact, while the right nacelle showed evidence of positive torque from the engine. Analysis of the propeller blades revealed nicks on the left propeller, suggesting low power. Furthermore, the investigation identified that two fuel injectors on the left turbine were in poor condition.
Regarding the flight controls, the right elevator compensator was found deflected upward. While the left flap actuator terminal was found broken, testing by EMBRAER demonstrated that such a failure would not have caused the observed flight path. The investigation also noted that the left engine fuel lever was in the "cut" position, yet the propeller had not feathered.
Crucially, the investigation found that the Fuel Control Unit (FCU) of the right engine had been affected by a substance consisting of a mixture of dust and engine oil, which had caused the governor lever to stick in the closed position. It was noted that EMBRAER had previously consulted authorities regarding the need for a filter on the P3 line due to operations on unprepared runways, but no action had been taken.
Findings
- The aircraft was operating at maximum takeoff weight with low airspeed and restricted visibility.
- Partial loss of power in the right engine likely occurred after takeoff.
- The pilot likely attempted to return to the airport by initiating a left turn but could not maintain altitude.
- Contamination of the FCU by dust and oil prevented proper governor control.
- The lack of flight and voice recorders prevented a definitive reconstruction of the final two minutes of flight.