What happened
On October 11, 2012, a Xavante A-122-B, registration PP-KBP, was conducting a navigation training flight from Luziânia to Caldas Novas, Goiás. The flight was operated by Aeroclube de Brasília with an instructor and a student on board. Following a touch-and-go maneuver on runway 09 at Caldas Novas Aerodrome (SBCN), the engine failed while the aircraft was between 1,000 and 1,500 feet of altitude.
The instructor successfully restarted the engine at low power and decided to land on runway 27. However, during the landing roll, the engine failed again after the power was reduced. Although the instructor managed to restart the engine once more to taxi to the parking area, the engine failed a third time while the aircraft was stationary. The crew evacuated the aircraft and contacted the flight club.
The investigation
CENIPA investigators learned of the occurrence through third parties, as the operator had not officially notified the authorities. Upon arrival, the investigation team discovered that a mechanic from the flight club had already performed corrective maintenance on the engine without authorization from the investigators, which significantly hindered the technical analysis.
Despite the unauthorized intervention, the investigation identified several critical discrepancies regarding the aircraft's airworthiness and maintenance standards. These included excessively carbonized spark plugs, damaged wiring, an expired fire extinguisher, and the absence of static dischargers. Additionally, the fuel filler neck lacked any indication of the required fuel type, and the aircraft's checklist was found to be deficient as it did not include an external inspection step.
Findings
- The engine failure was likely caused by the poor condition of the spark plugs and engine wiring.
- The aircraft's maintenance and operational oversight were compromised by unauthorized post-incident repairs.
- Significant maintenance discrepancies were present, including damaged electrical components and expired safety equipment.
- The operator had a recent history of serious incidents involving other aircraft in its fleet.