What happened
On 29 June 2015, an Etihad Airways Airbus A330-243, registered A6-EYN, was operating a scheduled passenger service from Abu Dhabi International Airport to Dublin, Ireland. Approximately 58 minutes into the flight, while cruising through Iranian airspace, the copilot—acting as the pilot monitoring—requested tissue to address nasal congestion. Upon blowing his nose, the crew member observed blood and mucus. Shortly after, the copilot reported feeling unwell and experienced a tingling sensation throughout his body before losing consciousness for approximately one minute.
Recognizing the medical emergency, the commander requested assistance from the cabin manager, who provided oxygen to the incapacitated pilot. The copilot was subsequently moved to the cabin, where a medical doctor traveling as a passenger provided care. The commander declared a PAN-PAN and initiated an emergency return to Abu Dhabi. An off-duty Boeing 777 captain, also a passenger on the flight, assisted the commander with flight operations. The aircraft landed safely in Abu Dhabi, and the crew member was transferred to an airport clinic, where he was later cleared by medical staff.
The investigation
The UAE Air Accident Investigation Sector (AAIS) conducted an inquiry into the incident, involving coordination with the aircraft manufacturer's representative from France. The investigation reviewed the flight crew's medical history, the use of over-the-counter medications, and broader safety data regarding pilot incapacitation within the UAE. Investigators examined the physiological effects of pressurized flight and the potential for vasovagally-induced syncope. While post-incident medical examinations of the copilot yielded no specific underlying pathology, the investigation looked into several environmental and physiological stressors present during the flight.
Findings
Investigators were unable to identify a definitive medical cause for the sudden loss of consciousness, as all subsequent medical tests were inconclusive. However, several contributing factors were identified that may have compromised the pilot's medical fitness:
- The presence of nasal congestion prior to the flight.
- The potential side effects of an over-the-counter nasal spray used within 24 hours of departure.
- The physiological impact of flying in a pressurized cabin.
- The influence of the pilot's biological clock.
- The psychological impact of seeing blood, which may have triggered vasovagal syncope.
Safety action
The investigation resulted in several recommendations for both the operator and the GCAA. For Etihad Airways, recommendations included updating training manuals regarding abnormal situations, reviewing policies for cockpit assistance during incapacitation, and encouraging pilots to consult medical professionals regarding the use of over-the-counter medications. For the GCAA, recommendations focused on improving safety communication with pharmacies regarding aviation-related medication risks, conducting studies on the prevalence of drug use among pilots, and establishing clearer regulations for post-incident drug and alcohol testing.