What happened
On February 23, 2016, a Japan Airlines Boeing 737-800, registered JA322J, was preparing for a scheduled flight from New Chitose Airport to Fukuoka Airport. After pushing back from the apron, the aircraft was taxiing when a sudden and intense snowfall began. To prevent ice and snow accumulation on the airframe, the captain decided to move the aircraft to a designated apron.
While holding on a taxiway due to deteriorating visibility and heavy snow, the crew noticed unusual odors and smoke filling the cabin. Simultaneously, a flame was identified at the rear of the No. 2 engine. Due to the ongoing fire and the inability to maintain engine stability, the crew initiated an emergency evacuation at approximately 15:10 JST via the evacuation slides at Taxiway T2. The aircraft was carrying 165 people, including 159 passengers and six crewmembers. During the evacuation, one passenger sustained a serious injury after falling from the hip while descending the slide, and two others suffered minor injuries. The aircraft itself sustained no damage.
The investigation
The JTSB investigation focused on the mechanical failures and the sequence of events leading to the fire. Investigators examined the engine components, specifically the fan blades and low-pressure compressor, as well as the aircraft's air-conditioning system. The investigation also reviewed flight data recorder (FDR) and cockpit voice recorder (CVR) logs, along with interviews from the crew and ground personnel. The inquiry looked into how rapid weather changes influenced engine oil behavior and evaluated the effectiveness of the emergency evacuation procedures, including passenger compliance with baggage restrictions.
Findings
- Rapid weather deterioration caused heavy snow to accumulate on the engine's fan blades and low-pressure compressor.
- This icing caused a decrease in airflow and pressure within the engine seals, leading to engine oil leakage.
- The leaked oil vaporized into the cabin through the air-conditioning system, creating the observed smoke and odors.
- Some of the leaked oil accumulated in the tailpipe, where it ignited, resulting in a visible flame at the rear of the No. 2 engine.
- During the evacuation, several passengers attempted to descend the slides while carrying hand luggage, which hindered the flow of the evacuation and required cabin attendants to intervene.