What happened
On January 1, 1996, an EMB-720D, registration PT-OSJ, operated by Bahia Táxi Aéreo, was performing a visual flight rules (VFR) flight from Salvador to Maraú. During the flight, the pilot diverted from the original flight plan to land at an uncertified airstrip in Morro de and São Paulo, Valença, Bahia. After picking up three passengers, the aircraft attempted takeoff from runway 05.
Shortly after departing the ground, the engine failed. The aircraft lost altitude and struck a coconut tree approximately 200 meters from the runway threshold before impacting the ground. The impact triggered a fire that completely destroyed the aircraft. The pilot and three passengers were rescued by bystanders and sustained minor injuries.
The investigation
CENIPA investigators examined the engine, the maintenance records, and the operational procedures of the operator. While the aircraft's weight and center of gravity were within limits, the investigation revealed that the engine had been exhibiting irregular, "rough" performance, which had been reported to the company's maintenance department. Maintenance personnel had released the aircraft for flight, claiming the engine was simply "running in."
Physical examination of the Lycoming engine showed deep marks on the bearings and crankshaft, characterized by discoloration typical of high-temperature operation. This provided evidence of deficient lubrication within the engine. Additionally, investigators found spark plugs soaked in oil, which likely impaired combustion.
Findings
- Deficient maintenance: The engine failure was caused by a lack of proper lubrication, and the operator failed to investigate previously reported engine irregularities.
- Deficient supervision: The company's maintenance management failed to oversee technical works, and there was a lack of administrative oversight regarding the use of uncertified airstrips.
- Operational irregularities: The pilot intentionally operated at an uncertified airstrip, violating current aviation regulations.
- Deficient planning: The pilot's decision-making was compromised by the lack of an adequate pilot training program within the company.
Safety action
CENIPA issued several mandatory safety recommendations to the operator, Bahia Táxi Aéreo, including:
- Immediate implementation of maintenance controls to ensure all reported irregularities are investigated and corrected.
- A prohibition on operating aircraft at uncertified airstrips due to the inherent risks.
- The establishment of a pilot training and recurrent instruction program within six months, focusing on aircraft performance and operational limits.