What happened
On August 12, 2020, an Airbus A320-214, registration EC-IEF, was operating a commercial passenger flight from Madrid Barajas to Barcelona-El Prat. While descending toward the TOTKI waypoint as part of the CASPE2N arrival, the aircraft was maneuvering visually to avoid cloud formations.
At approximately 12:08:21 local time, the flight crew activated the fasten seatbelt sign as a precaution. Roughly fifty seconds later, between 12:09:10 and 12:09:51, the aircraft entered an area of unexpected turbulence. The vertical acceleration reached +2.15 g. During this period, cabin crew members were in the process of securing the cabin for landing. The sudden movement caused crew members in the rear of the aircraft to fall to the floor, leading to one serious injury when a cabin crew member struck a galley counter.
The investigation
The CIAIAC investigation examined the meteorological conditions, the aircraft's onboard systems, and the crew's actions. The investigation found that while the flight plan indicated potential cumulonimbus activity in the area, no specific SIGMET warnings or turbulence reports had been issued by air traffic control or other aircraft.
Investigators noted that the aircraft's weather radar was set to the "Weather" (WX) mode, which provides information on precipitation but does not detect turbulence in clear air. Furthermore, the investigation established that the flight crew did not report the turbulence to air traffic control following the event, despite operator and regulatory requirements to do so for moderate or severe turbulence. The crew also did not initially report the injury to medical services, as the severity was not apparent until the crew member sought hospital treatment upon returning to Madrid.
Findings
- The primary cause of the accident was the aircraft entering an undetected area of turbulence during the approach to Barcelona.
- The aircraft's radar was configured to display precipitation only, meaning it could not detect turbulence in clear air.
- There were no prior reports of turbulence from other aircraft, ATIS, or air traffic control services for that specific area.
- The cabin crew were actively securing the cabin when the turbulence occurred, which contributed to the injury.