What happened
On May 3, 2014, a Cessna 208B, registration PP-EPV, departed from Marabá Airport (SBMA) for a local test flight to investigate an oil leak. During the flight, the crew discovered that the engine would not respond to throttle inputs, remaining stuck at high power.
The crew declared an emergency and returned to the airfield. During the final approach, the engine was shut down. Shortly before touchdown, the flaps were retracted. The aircraft struck the ground 12/0 meters before the runway threshold, causing light damage to the left wing, the right horizontal stabilizer, and the landing gear. All three occupants—two pilots and one passenger—were uninjured.
The investigation
CENIPA investigators examined the engine components, specifically the fuel pump and the Fuel Control Unit (FCU). Analysis by the DCTA revealed that the FCU's pressure valve had experienced a seizure due to longitudinal scratches on the valve and sleeve. This seizure caused a stagnation of fuel flow, preventing the reduction of engine power as required by the aircraft's flight manual.
The investigation also focused on the crew's actions during the emergency. Although a briefing had been conducted, the second pilot performed the engine shutdown earlier than agreed and retracted the flaps during the short final, believing it would improve the glide ratio. The investigation noted that the operator lacked a formal hierarchy or standardized procedures for flight assignments, which impacted crew coordination.
Findings
- Mechanical failure: A seizure in the Fuel Control Unit (FCU) prevented the pilot from reducing engine power.
- Improper pilot judgment: The decision to retract the flaps and the premature engine shutdown significantly degraded the aircraft's glide performance.
- Lack of Crew Resource Management (CRM): Poor communication and a failure to adhere to the established emergency briefing led to uncoordinated actions between the pilots.
- Inadequate training: The second pilot demonstrated a lack of theoretical knowledge regarding the effects of flap retraction on lift and glide ratio.
- Organizational deficiencies: The operator lacked formal emergency training, CRM training, and a structured management hierarchy to supervise operations effectively.