What happened
On October 21, 2013, a Piper PA-34-200, registration PT-KGK, was conducting a simulated IFR training flight near Maricá, Rio de Janeiro. While flying over the Maricá Lagoon, a propeller blade from the left engine and a portion of the propeller hub detached from the aircraft. This mechanical failure caused the aircraft to lose control and enter a vertical descent, ultimately impacting the water. The impact destroyed the aircraft, and both occupants—an instructor and a student pilot—were killed.
The investigation
CENIPA investigators examined the maintenance history of the aircraft and its components. The investigation focused on the left engine propeller (serial number AU5426E), which had been overhauled in September 2010. While the aircraft's airworthiness and registration certificates were valid, investigators discovered that the required Eddy Current Inspection (ECI) mandated by FAA Airworthiness Directive 2009-22-03 had not been performed.
At the time of the accident, the propeller had operated for approximately 918 hours since its last compliant inspection. The investigation revealed that the maintenance workshop at Aeroclube do Brasil had failed to identify the applicability of this specific Airworthiness Directive. Furthermore, the responsibility for analyzing and implementing these directives had been improperly delegated to an employee other than the designated Service Quality Manager or Inspector.
Findings
- Lack of compliance with Airworthiness Directive 2009-22-03, which prevented the detection of a crack in the left-hand propeller hub.
- Managerial oversight within the maintenance workshop, where the delegation of responsibility for monitoring airworthiness directives led to the aircraft being released for flight without meeting required safety standards.
- The detachment of the propeller blade and hub caused the aircraft to become uncontrollable.