What happened
On 29 October 2019, an Asiana Airlines flight, operating an A321-200 registered as HL8071, was on approach to Kaohsiung International Airport in Taiwan. The flight had departed from Incheon International Airport with 145 passengers and 9 crew members on board.
During the descent, approximately 20 minutes after the captain had taken over the role of pilot flying, the first officer suddenly lost consciousness while waiting for a weather printout. The captain immediately recognized the medical emergency, declared a MAYDAY, and took sole control of the aircraft.
To manage the cockpit environment, the captain requested cabin crew assistance. The purser entered the flight deck and provided first aid, including administering oxygen and massaging the pilot's limbs. A passenger, identified as a medical doctor, also assisted in stabilizing the first officer. The incapacitated pilot was eventually moved to a passenger seat in the cabin. The captain continued the approach using autopilot and manually transitioned to manual control just before landing the aircraft safely at Kaohsiung International Airport.
The investigation
The investigation, conducted by the ARAIB, examined the flight recorders, crew training records, and the physiological state of the flight crew. Investigators looked into the fatigue levels of the crew, noting that while the duty roster complied with regulations, the first officer had only averaged approximately two hours of sleep per night for the 72 hours preceding the incident.
Medical examinations following the event were inconclusive regarding a specific medical diagnosis, though the operator's medical officer suggested possibilities such as vasovagal syncope or epilepsy. The investigation also reviewed the effectiveness of the airline's safety management system and the adequacy of the cabin crew's emergency manuals regarding crew incapacitation.
Findings
- The primary cause of the incident was the loss of consciousness of unknown cause.
- Significant contributing factors included a lack of individual fatigue management and a lack of awareness regarding sleep deprivation.
- There was an identified lack of safety culture within the organization regarding the management of fatigue.
- The investigation found that the first officer had accumulated significant sleep debt in the days leading up to the flight.
- While the cabin crew responded according to their manual, certain specific duties for handling crew incapacitation were not clearly defined in the existing documentation.