What happened
On 05 August 2019, an Airbus A321-231, registration G-MEDN, operated by British Airways, was performing a scheduled international flight from London Heathrow to Valencia Airport. During the flight over the Pyrenees, the flight crew received an engine stall caution on engine number two, which resolved automatically. Shortly after, the cabin crew reported a slight mist in the passenger cabin, and an engine oil filter clog warning appeared.
While on final approach to Valencia at approximately 6,000 ft, thick white smoke began entering the flight deck and the passenger cabin. The pilots donned oxygen masks and continued the approach. Upon landing on runway 12, the aircraft experienced further alerts, including forward cargo smoke and engine oil pressure warnings. The captain stopped the aircraft on a taxiway and declared a MAYDAY, subsequently ordering an emergency evacuation.
During the evacuation, six of the eight available slides were deployed. All 183 persons on board (8 crew and 175 passengers) were evacuated safely, with no injuries reported, although three passengers were transferred to a hospital as a precaution.
The investigation
The CIAIAC investigation focused on the mechanical condition of engine number two and the sequence of cockpit and cabin alerts. Investigators examined the engine's performance history and the technical state of the engine components. The investigation also reviewed the crew's management of the emergency, the effectiveness of the evacuation, and the communication challenges experienced by the cabin crew while wearing protective breathing equipment (PBE).
Findings
- The primary cause of the incident was the misalignment and breakage of bearing number 3 and its hydraulic seal within engine number two.
- This mechanical failure allowed engine oil to contaminate the engine's bleed air system, which subsequently introduced smoke into the passenger cabin and oil into the aircraft's anti-ice system.
- The investigation found that the engine's oil loss was directly linked to this bearing failure.
- While the cabin crew experienced difficulty communicating with the flight deck while wearing smoke hoods, the operator had already initiated training improvements to address these communication barriers.