What happened
On March 15, 2006, an R22B helicopter, registration PP-MEJ, was conducting a flight training session near Piraquara, Brazil. After completing hovering exercises, the student pilot began a takeoff maneuver. While climbing through approximately 200 feet, the engine suffered a sudden and complete failure, triggering the low RPM warning.
The flight instructor immediately took control of the aircraft to execute an autorotation procedure. During the landing attempt on unprepared terrain, the pilot performed a flare that was too aggressive, likely in an attempt to clear obstacles. This maneuver caused the tail rotor cone to strike the ground and the skid to collide with a tree trunk, causing the helicopter to spin 1/2 turn and capsize onto its right side. The instructor escaped without injury, while the student pilot sustained minor injuries. The aircraft sustained severe damage.
The investigation
CENIPA investigators examined the engine and its components following the accident. While the carburetor showed signs of contamination from a corrosive liquid—potentially originating from the aircraft battery—no internal mechanical failures were found that could definitively explain the sudden engine shutdown. Fuel and filters were inspected and found to be clean and free of impurities.
The investigation also scrutinized the maintenance practices of the operator, Escola de Aviação Civil Asas Rotativas Ltda. Investigators discovered that the maintenance department was performing unauthorized tasks, including engine and carburetor replacements, using unqualified personnel outside of a certified workshop. Furthermore, the company's fuel handling procedures were found to be non-compliant with standard safety regulations.
Findings
- Improper maintenance oversight: The operator lacked adequate supervision, allowing unqualified mechanics to perform complex maintenance tasks beyond their authorized scope.
- Pilot judgment: The instructor's decision to land in an area containing obstacles, rather than selecting a nearby clear area, contributed to the impact.
- Maintenance irregularities: The use of uncertified personnel and unauthorized workshops created latent safety risks within the organization.
- Engine failure: The exact cause of the sudden engine power loss could not be determined, though the carburetor was found to be contaminated with corrosive liquid.