Investigation Summary
Allied Air Flight 111 was operating a scheduled cargo service from Lagos to Abidjan, with a planned intermediate stop at Accra. During the pre-flight phase in Lagos, the Flight Engineer noted a Constant Speed Drive (CSD) amber caution light, which was disconnected with the captain's permission before departure. The flight encountered turbulence and inclement weather en route. Upon arrival at Accra, the crew initially performed an ILS-coupled approach. At 500 feet, the captain disconnected the autopilot to fly manually, entering heavy rain and instrument meteorological conditions (IMC) that severely restricted visibility. The approach became unstable, with the aircraft maintaining a high speed of 167 knots. The aircraft eventually touched down at 154 knots. While the Flight Data Recorder (FDR) indicated touchdown at 5,807 feet beyond the threshold of Runway 21, the investigation's contributory factors also cited a figure of 6,060 feet. Despite the deployment of thrust reversers and both normal and emergency pneumatic brakes, the aircraft could not be stopped. The crew failed to deploy the speed brakes, and the nose gear remained off the ground until the aircraft struck the perimeter fence. The aircraft's path of destruction included the ILS localizer and a Mercedes-Benz minibus traveling on Giffard Road, before the airframe came to rest near El-Wak Stadium.
Final Conclusions
The Ghana Accident Investigation Bureau (AIB) concluded that the primary cause was the captain's decision to continue the landing instead of aborting at the missed approach point, despite poor visibility and uncertainty regarding the aircraft's position on the runway. Contributory factors included the manual operation of an unstable approach in heavy rain, landing approximately 6,060 feet from the Runway 21 threshold (leaving only 4,000 feet to the threshold of Runway 03), landing with a 15-knot tailwind (exceeding the 10-knot limit), crew fixation on the localizer rather than runway lighting, and the failure to deploy speed brakes upon touchdown.
Photographic Evidence (1)
Video Analysis
No video analysis linked for this case file yet.
Airframe & Maintenance
Crew Experience
Captain
Survived with minor injuries.
First Officer
Survived with minor injuries.
Systems & Failure Modes
Speed Brakes
Aerodynamic surfaces on the wings used to reduce lift and increase drag; the crew failed to deploy these during the landing roll, reducing braking effectiveness.
Thrust Reversers
Systems that redirect engine exhaust forward to slow the aircraft; these were deployed but were insufficient to stop the aircraft within the remaining runway distance.
ILS Localizer
A ground-based transmitter providing lateral guidance to the runway; the aircraft destroyed this structure during the overrun, and debris from it struck a nearby taxi.
Interesting Facts
- 01The aircraft involved (5N-BJN) performed the final flight for Pan American World Airways on December 4, 1991, flying from Bridgetown, Barbados to Miami, Florida.
- 02The 10 fatalities were all occupants of a Mercedes-Benz TN 207 minibus struck by the aircraft on Giffard Road.
- 03The aircraft landed with a 15-knot tailwind, which was 5 knots above the maximum allowable limit for the Boeing 727.
- 04The nose gear never touched the ground during the entire landing roll until the aircraft impacted the perimeter fence.
- 05The captain reported that the windshield wipers were unable to clear the rain, though investigators found they were only three-quarters switched on.
- 06The aircraft touched down approximately 5,807 to 6,060 feet from the beginning of Runway 21, leaving insufficient distance to stop.
Safety Actions & Advisories
Missed Approach Procedures
The investigation emphasized the necessity of adhering to missed approach points when visibility is lost or the approach becomes unstable.