What happened
On January 29, 2004, a BE-95 operated by Cândido Táxi Aéreo Ltda was performing a transport flight of bank mailbags from Araguaína, TO, to Belém, PA. While cruising at 7,500 feet over Abel Figueiredo, PA, the pilot noticed a significant oil leak and a drop in oil pressure in the left engine.
Because the aircraft was operating significantly above its maximum takeoff weight, the pilot determined that maintaining level flight on a single engine would be impossible. The pilot decided to perform an emergency landing on a dirt road at Fazenda Curable Azul. During the approach, the pilot reduced power to the affected engine but did not feather the propeller, fearing a loss of control during the single-engine approach. The aircraft struck the ground at an angle of approximately 135 degrees, resulting in severe damage to the wings, landing gear, fuselage, propellers, and engines. All four occupants—the pilot and three passengers—emerged from the wreckage uninjured.
The investigation
CENIPA investigators examined the engine systems, specifically focusing on the lubrication system and the oil filler neck. The investigation revealed that the oil dipstick for the left engine was not properly secured in the locked position, which likely occurred during the pre-flight inspection.
Further analysis of the aircraft's weight and balance showed that the aircraft had departed with approximately 335 kg above the manufacturer's maximum takeoff weight. Additionally, investigators found that the company's pilots were not consistently recording aircraft discrepancies in the logbooks, which hindered the monitoring of mechanical issues. The investigation also noted that the pilot's decision not to feather the propeller, while intended to maintain control, contradicted the aircraft's emergency procedures and significantly increased aerodynamic drag.
Findings
- The primary cause of the engine oil loss was the failure to properly secure the oil dipstick following the pre-flight check.
- The aircraft was operating with an excessive weight of 335 kg above the maximum allowable takeoff weight, which severely degraded single-engine performance.
- The pilot's decision not to feather the propeller increased drag, making it impossible to maintain level flight under the overloaded conditions.
- Operational failures included inadequate flight planning regarding weight and balance, and a lack of effective oversight by the operator regarding weight verification.
- There was evidence of insufficient training or emphasis on single-engine emergency procedures, specifically regarding engine shutdown and propeller feathering.