What happened
On February 9, 2010, a cargo Airbus A300 B4-203F arriving from Istanbul, Turkey, landed on runway 32R at Cologne/Bonn Airport during snowy, nighttime conditions. Following touchdown, the crew utilized the brakes and thrust reversers to decelerate. During the deployment of the thrust reversers, the aircraft experienced a slight leftward veer at approximately 80 knots, which the crew corrected using the rudder pedals.
As the thrust reverser deployment sequence concluded, the crew noted that the green REV and yellow REV-UNLK indicators remained illuminated for the right engine. Upon reaching the parking position, ground personnel informed the crew that the left fan reverser translating cowl of the right engine was missing. The debris from the detached component had been left on the runway, where it was subsequently struck by a following Boeing 767 cargo aircraft, causing damage to its right engine inlet and landing gear wheels.
The investigation
The BFU examined the wreckage of the detached cowl and the damage sustained by both aircraft. The investigation focused on the mechanical state of the right engine's thrust reverser assembly. Investigators found that while the upper and middle ball screws were in the retracted position, the lower ball screw was extended by 22 cm. The connection tube to the cowl had broken, and the cascade vanes showed signs of abrasion near the ball screw connection forks. Additionally, the inspection revealed that the rivet holes connecting the inner and outer cowl sections had been heavily worn, and the cowl had partially torn away from the guide rail.
Findings
- The primary cause of the incident was the structural failure of the thrust reverser assembly, specifically the detachment of the left fan reverser translating cowl.
- The failure was characterized by worn rivet holes and a broken connection tube.
- The presence of debris on the runway led to secondary damage to a following aircraft.