What happened
On February 16, 2017, a BO-105S helicopter, registration PR-MER, operated by Heringer Air Taxi Ltd., was performing a flight from São Félix do Xingu Aerodrome to Pykany Village in the state of Pará. Approximately fifteen minutes into the flight, the pilot detected a burning odor within the cabin. While the flight instruments showed no immediate abnormalities, the pilot decided to perform a precautionary landing in an open area roughly 66km from the departure airfield.
Upon landing, the pilot observed a significant amount of smoke emanating from the rear of the aircraft. The pilot directed the passenger to evacuate immediately. However, during the abandonment of the aircraft, the pilot failed to shut down the engines. Shortly after the crew exited, a fire ignited, which ultimately consumed and destroyed the aircraft. Both the pilot and the passenger escaped the incident without injuries.
The investigation
CENIPA's investigation into the occurrence revealed several maintenance and operational discrepancies. While the aircraft held a valid airworthiness certificate, the engine logbooks were outdated, specifically regarding the overhaul of the starter-generators. It was discovered that the starter-generators for both the left and right engines were approximately 650 hours overdue for overhaul.
The investigation also examined the pilot's training and the company's safety culture. It was noted that the pilot's training and recent check flights had not adequately covered specific fire and smoke emergency procedures for this aircraft type. Furthermore, the investigation found that within the operator's organizational culture, there was a collective acceptance of informal practices that deviated from official manuals, including the practice of abandoning aircraft without performing the required engine shutdown.
Findings
- Decision-making process: The pilot performed a precautionary landing rather than the emergency landing required by the flight manual for burning odors, which contributed to the severity of the event.
- Inadequate emergency management: The decision to abandon the aircraft without cutting off the engines allowed the fire to spread and intensify.
- Organizational culture: A lack of standardization within the company allowed for the adoption of non-standard procedures that diverged from the aircraft's operating manual.
- Training deficiencies: The pilot's training did not sufficiently emphasize the specific fire and smoke procedures necessary for effective emergency management.
- Maintenance oversight: The starter-generators were significantly overdue for their scheduled overhaul.