Overview
• Operator: Allied Air Cargo
• Aircraft Model: Boeing 737-400 Freighter
• Registration: 5N-JRT
• Flight Number: 4W-206
• Route: Lagos (Nigeria) to Abuja (Nigeria)
• Date: 11 December 2024
• Occupants: 6 (2 passengers, 4 crew)
• Injuries: None reported
• Damage: Substantial
• Investigation: Ongoing by Nigeria’s NSIB
Incident Summary
Allied Air Cargo flight 4W-206, a Boeing 737-400 freighter, was conducting a cargo flight from Lagos to Abuja when it suffered a runway excursion upon landing at Abuja’s Runway 22. The aircraft touched down at 157 knots CAS, but during the landing roll, the right main landing gear failed, causing the aircraft to veer off the right side of the runway into a ditch.
The fire warning and landing gear horn activated, and the aircraft’s No. 1 engine nacelle dragged along the runway for approximately 1,172 metres before the aircraft came to a rest in the grass verge, making a 170-degree turn to the right. The crew shut down the engines, secured the aircraft, and all occupants safely exited through the forward main door without injury.
Ground inspections revealed only left main gear tracks on the runway, while the right main gear strut was found separated from the aircraft in the grass. The aircraft sustained substantial damage and has been grounded.
Sequence of Events
Final Approach and Landing
• At 10:03:23, the first officer (FO) called out “three nautical miles”, and the crew requested clearance to land.
• At 10:03:59, the FO reported that Flaps 30 could not be deployed. The captain acknowledged the issue, and the crew elected to continue with Flaps 15 as the aircraft’s weight was within operational limits.
• At 10:04:05, the aircraft was 0.6 nautical miles from touchdown, and Abuja Tower issued landing clearance.
Touchdown and Runway Excursion
• At 10:04:24, the aircraft touched down at 157 knots CAS.
• The speed brakes and reversers deployed automatically, and the crew attempted to maintain control.
• A bang was heard from the aircraft’s right side, followed by the right landing gear collapse.
• The aircraft veered off the runway to the right, with the No. 1 engine nacelle dragging for over 1,172 metres before stopping in the grass.
• The crew secured the aircraft and all occupants evacuated safely.
Investigation & Preliminary Findings
Nigeria’s NSIB Preliminary Report
• Flaps 30 failed to deploy, requiring the crew to land with Flaps 15.
• The right main landing gear collapsed upon landing, leading to loss of directional control.
• Fire warning and landing gear alerts activated shortly after touchdown.
• No adverse weather conditions were present, as the incident occurred under Visual Meteorological Conditions (VMC).
Aircraft Status & Next Steps
• The aircraft remains grounded at Abuja International Airport.
• Nigeria’s NSIB continues the investigation, focusing on the landing gear failure and flap system malfunction.
• The airline and regulators are reviewing maintenance records and operational procedures to determine potential contributing factors.
Analysis & Recommendations
Landing Gear Structural Integrity
• Investigators should examine whether pre-existing stress, fatigue, or improper maintenance contributed to the landing gear failure.
• Inspection of previous landing cycles and any hard landings should be conducted to identify potential wear or damage.
Flap System Reliability
• The flap anomaly required a higher approach speed, increasing stress on the landing gear during touchdown.
• A review of maintenance logs and flap system diagnostics should determine whether this was a mechanical failure or operational issue.
Runway Excursion Mitigation
• Given that the right main landing gear collapsed, the airline should consider enhanced landing gear checks as part of standard operating procedures.
• The crew response was appropriate, but post-landing control strategies should be reviewed for potential improvements in directional stability.
Disclaimer
This report is based on available information as of 3 February 2025. While every effort has been made to ensure accuracy, the completeness of the details cannot be guaranteed. If you are the rightful owner of any referenced materials and wish them removed, please email takedown@cockpitking.com.
