What happened
On 20 March 2022, an American Airlines Boeing 777-223, registration N777AN, departed from Josep Tarradella Barcelona-El Prat Airport bound for Miami International Airport. While the aircraft was en route over the province of Zaragoza, the pilot flying noticed a momentary disturbance in the flight controls. Shortly thereafter, a flight attendant reported that a passenger had observed a portion of the aircraft's wing detaching.
The pilot monitoring inspected the cabin and confirmed that the trailing edge of the left wing flap was damaged and the flap actuator fairing was missing. After evaluating the damage via photographs and consulting with dispatch, the crew declared a MAYDAY and initiated an emergency return to Barcelona. The aircraft landed on runway 07L at 11:18 h, performing an overweight landing without further incident. There were no injuries to the 261 passengers or 12 crew members on board.
The investigation
The CIAIAC opened an investigation on 1 April 2022. However, the investigators faced significant limitations as the aircraft had already been returned to service on 26 March 2022. The missing flap actuator fairing was never located, and the flight data and cockpit voice recorder data had been overwritten by subsequent flight recordings. Additionally, the operator declined to facilitate further contact with the line maintenance engineers who inspected the aircraft following the event.
Consultations with Boeing revealed that the manufacturer was aware of a similar occurrence in 2001 involving a different flap fairing. In both instances, the forward connection remained undamaged, but two bolts were missing and the three rear connections sustained damage.
Findings
- The left wing flap actuator fairing detached during flight.
- The front connection of the fairing was missing two bolts.
- All three rear connections of the fairing sustained damage.
- The investigation could not determine the specific cause of the detachment, though an impact while parked at the departure airport was unlikely as the operator had no record of such an event.