Investigation Summary
The investigation revealed a series of critical failures in Crew Resource Management (CRM) and technical oversight. During engine start, the crew noticed the No. 1 engine torque indicator was stuck at 76 percent. Although they consulted an engineer on board, he could not verify recent maintenance work, and the crew proceeded without referring to official documentation. More critically, as they commenced the takeoff roll, the aircraft's automated systems triggered 'Takeoff Flaps' and 'Auto feather' warnings. The No. 2 engine propeller had feathered, significantly reducing thrust. Despite the First Officer questioning if they should abort at 95 knots, the Captain continued. The aircraft was rotated prematurely before reaching V1 speed, leading to an immediate stall. The Accident Investigation Bureau (AIB) highlighted that the crew's decision to ignore multiple red flags and the company's poor safety culture were primary drivers of the catastrophe.
Final Conclusions
The Nigerian Accident Investigation Bureau (AIB) concluded in its final report (ASSOC/2013/10/03/F) that the primary cause was the crew's decision to continue takeoff despite abnormal No. 2 propeller RPM indications and a low-altitude stall resulting from low thrust. Contributory factors included rotating the aircraft before V1, ignoring flap configuration and auto-feather warnings, poor professional conduct, inadequate CRM, and weak regulatory oversight of the airline.
Video Analysis
No video analysis linked for this case file yet.
Airframe & Maintenance
Crew Experience
Captain
Pilot Flying (PF) who elected to continue takeoff despite warnings.
First Officer
Pilot Monitoring (PM) who questioned the takeoff but did not initiate an abort.
Systems & Failure Modes
Propeller Control Unit (PCU)
An undetermined malfunction in the No. 2 PCU caused the propeller to feather during the takeoff roll, resulting in a loss of thrust.
Aural Warning System
The system correctly provided 'Takeoff Flaps' and 'Auto feather' warnings, which the crew heard but disregarded.
Electronic Engine Control (EEC)
The crew performed multiple EEC tests before taxiing due to a stuck torque indicator, but the issue was not resolved before departure.
Interesting Facts
- 01The flight was a charter transporting the body of former Governor Olusegun Agagu for burial.
- 02The aircraft was 23 years old at the time of the accident.
- 03The crew failed to make standard V1 and Rotate calls during the takeoff roll.
- 04The No. 2 engine propeller feathered during takeoff, causing a massive thrust asymmetry.
- 05Sixteen people died in total, including one survivor who succumbed to injuries in the hospital.
Safety Actions & Advisories
Regulatory Oversight Review
The AIB identified inadequate regulatory oversight as a contributory factor, leading to recommendations for stricter monitoring of charter operators.
CRM Training Emphasis
The investigation emphasized the need for improved Crew Resource Management training to prevent captains from overriding safety-critical input from other crew members.