Incident Overview

Description
Nigeria Airways flight 471 suffered a runway excursion after landing on runway 19L at Lagos-Murtala Muhammed International Airport (LOS). The aircraft overran by 375 m and the nose gear collapsed. CAUSE OF ACCIDENT The probable cause of the accident is the chain reactions from the oversight of selecting the ground spoilers in the ARM position or deploying them manually when on ground. The first contributory factor to the accident is the absence of the thrust reverser, which could have activated the ground spoilers even if it had not been previously selected in the ARM position. The deployment of the reverse thrust buckets could have also contributed immensely to decelerate the aircraft in addition to the effect of the ground spoilers. The second contributory factor to the accident is the touchdown point. Since the crew is well aware of the deactivation of the reverse thrust, and also aware of the contamination aspect of the runway surface, it could have selected to touchdown at the very beginning of the runway as opposed to 2,743 ft from the threshold, or elected to land on the alternate but longer runway 19R. The third contributory factor is the fact that the aircraft went into a reverted rubber aquaplaning which increased the required landing distance and also prevented an effective deceleration of the aircraft in the adverse circumstances.
Primary Cause
Oversight in selecting ground spoilers, leading to deployment when not properly configured, and potentially exacerbated by the deployment of reverse thrust buckets.Oversight in selecting ground spoilers, leading to deployment when not properly configured, and potentially exacerbated by the deployment of reverse thrust buckets.Share on: