Airbus Industrie A319 112 N725UW accident near Philadelphia, Pennsylvania

Probable cause

an inadvertent encounter with clear air turbulence.

NTSB analysis

On November 23, 2015, at 1500 atlantic standard time, American Airlines flight 825, an Airbus A319, N725UW, encountered turbulence while in cruise from LF Wade International Airport (BDA), Hamilton, Bermuda, to Philadelphia International Airport (PHL), Philadelphia, Pennsylvania. According to the operator, the flight crew had flown the previous outbound flight from PHL to BDL at FL390, during which they experienced continuous light to very occasional moderate turbulence. The captain conferred with the dispatcher before departure to PHL on the return flight and the dispatcher suggested FL280 for a smoother ride. The flight departed BDA and climbed uneventfully to FL280. During cruise, the flight crew requested and received approval for a slight course deviation for some showers and then turned back on course and was clear of all convective activity and experiencing a smooth ride. The flight then encountered what the crew described as "severe" turbulence that lasted 5-10 seconds. At the time of the event, the airplane was on autopilot and the seatbelt sign was not illuminated. When the turbulence was encountered, the flight attendants were thrown to the floor resulting in one receiving a broken ankle. One passenger also experienced a minor injury. There was no damage to the airplane.

Text from the NTSB. Open the NTSB docket for DCA16CA023 for the full record.