What happened
On January 6, 2021, a Robinson R44 II helicopter, registration PR-WVW, was performing a private flight from Guarapari to Vila Velha, Espírito Santo. During the final approach to runway 05 at João Monteiro Aerodrome, the aircraft experienced an abnormal descent and a loss of control in flight. The helicopter collided with the ground in a wooded area near the runway threshold. The impact was high-energy, causing substantial structural damage, including the severing of the tail cone. Both the pilot and the passenger sustained fatal injuries.
The investigation
CENIPA's investigation focused on the aircraft's engine performance and maintenance history. Investigators examined the ignition system, specifically the magnetos, and discovered discrepancies in the right magneto and intermittent sparking in the left magneto. A critical finding was the presence of a non-standard washer in contact with the engine's right magneto electric terminal screw.
Analysis of security footage showed the aircraft began a descent that included a movement resembling a flare approximately six seconds after the initial descent began. The committee evaluated whether the pilot's attempt at an autorotation maneuver—a standard response to engine failure—was executed effectively, noting that the timing and intensity of the flare may have been misjudged due to the high rate of descent.
Findings
- The use of a non-standard washer in the magneto terminal screw indicated inadequate maintenance.
- The pilot acted as the technical manager and maintenance engineer for the aircraft, leading to a lack of independent oversight.
- There were indications of improper use of flight controls and potential errors in judging altitude during the flare maneuver.
- The aircraft's engine-related components showed signs of malfunction, potentially leading to a reduction in power or rotor RPM.
- Maintenance records for the airframe and engine were not up to date.