What happened
On March 10, 2021, an Airbus A300B4-203(F), registration YV506T, was preparing for a cargo flight from Bogotá’s El Dorado International Airport (SKBO) to Panama City. During the takeoff roll, as the aircraft reached approximately 40 knots, the number one (left) engine suffered a catastrophic, uncontained failure. The crew immediately aborted the takeoff, stabilized the aircraft, and returned to the cargo apron.
The failure resulted in the disintegration of several engine components. Debris from the engine, including stages 3 and 4 of the low-pressure turbine, was ejected with enough force to penetrate the airport's perimeter fencing and strike a warehouse door outside the airfield. The aircraft sustained damage to the fuselage, wing undersides, and flight control surfaces due to the impact of flying engine parts. There were no injuries among the six crew members on board.
The investigation
The GRIAA investigation revealed that the aircraft had arrived in Bogotá from Maiquetía, Venezuela, earlier that day, having experienced significant engine vibrations. Although maintenance performed a visual inspection and checked the chip detector, no abnormalities were found, and the crew proceeded with the scheduled flight to Panama.
Investigators examined the engine's maintenance history and found that the failure was linked to the fatigue-induced separation of low-pressure turbine blades. The investigation also scrutinized the operator's adherence to Airworthiness Directive FAA 2012-02-07, which required the replacement of specific older-design turbine disks. Furthermore, the investigation looked into the effectiveness of the operator's borescope inspection program and supplier oversight.
Findings
- The primary cause of the incident was the failure of the left engine due to the fatigue-induced separation of low-pressure turbine blades.
- The operator failed to comply with the requirements of Airworthiness Directive FAA 2012-02-07, which mandated the replacement of the failed blades.
- The operator lacked an effective program for verifying supplier services and supervising borescope inspection results, which prevented the identification of blade tip erosion noted seven cycles prior to the failure.
- The operator did not perform a detailed inspection following the severe engine vibrations reported during the previous flight leg.