Description

On 17 January 2022, the PF Captain of an Airbus A330-900 (F-HUUG) being operated by Corsair on a scheduled overnight international passenger flight from Fort-de-France to Paris Orly as CRL25 became wholly incapacitated early in the cruise and unable to participate in the operation of the aircraft following earlier indications that he was unwell. The First Officer took over with a member of the cabin crew occupying the Captain’s seat and a PAN, subsequently upgraded to a MAYDAY, was declared and an en-route diversion was made to Lajes. On arrival, the Captain was transferred to hospital where he remained.

Investigation

A Serious Incident Investigation was carried out by the French Civil Aviation Accident Investigation Agency, the BEA. The FDR was downloaded and provided useful information but the CVR was not isolated so relevant data was overwritten. Recordings of relevant communications and radar data were available.

The 58 year-old Captain had a total of approximately 16,000 hours flying experience and had gained his command on A330 eighteen months prior to the event under investigation in June 2020. Prior to that he had been a naval pilot for ten years before obtaining an Air Transport Pilot Licence (ATPL) and working as a simulator instructor on the A320 from 2004 and on the A330 from 2010. He was then employed as a First Officer by several other airlines before joining Corsair as a First Officer on the Boeing 747. He then transferred to the A330 before becoming an A330 Captain eighteen months prior to the event under investigation.

The 40 year-old First Officer had a total of 9,300 hours flying experience and had six years experience on the A320 followed by seven years on the A330 up to 2019 with several other airlines. After Covid-related unemployment, she had joined Corsair eight months prior to the event under investigation.

The Chief Purser had been employed as cabin crew at Corsair for 26 years, had just been promoted to Chief Purser and was carrying out her second rotation in this position at the time of the event under investigation. The member of cabin crew who assisted the First Officer had been employed by Corsair since 2001 and she had no pilot experience.

What Happened

The flight crew were aware that Fort-de-France airport would be closing soon after their departure and had filed a departure alternate as Antigua airport and en-route alternates as Lajes (Portugal) and Santiago (Spain). It was agreed that the Captain would act as PF and the First Officer as PM. Flight preparation and departure proceeded normally and the Captain initially flew the aircraft manually before engaging the left side AP when passing FL130 on a climb to an eventual cruise altitude of FL380. He stated that he had told the First Officer that he felt tired and was going to rest for a while, but added that he did not remember falling asleep or (subsequently) being woken up. However, she stated that he had not told her he needed to rest and that as a result, AP1 remained engaged and she continued to act as PM.

The First Officer then obtained the oceanic clearance and contacted the airline’s Operations Control to update the meteorological information. Due to a failure of the ACARS on-board printer on the aircraft’s outbound leg which had been recorded as an ADD in the aircraft Technical Log, they had to obtain updated weather data by calling Operations Control.

About half an hour after takeoff, with the flight approaching its initial cruise altitude of FL300, the First Officer saw that the Captain seemed to be asleep and did not respond when she spoke to him or shook him. After two such attempts to wake him, she made the prescribed emergency interphone call in the event of pilot incapacitation to summon the Chief Purser to the flight deck. When she entered the flight deck, the Captain was “coming round” and said he was “a little tired but fine”. At that point, the flight was approximately 200 nm north-east of Fort-de-France abeam Antigua.

The Chief Purser asked the Captain a series of questions which were answered as expected. She then “applied moist compresses to his neck and forehead” and took his temperature, blood pressure, blood sugar and blood oxygen level. All were normal except the last one which was 90% compared to the figure for a normal person on good health and physical condition which is over 93% up to a (cabin) altitude of 10,000 feet. It was noted that at the time FDR data showed that the cabin altitude was 5000 feet and it subsequently reached a maximum of 6,500 feet at FL380.

The First Officer asked the Captain what his intentions were and he replied that he wished to continue the flight. The Chief Purser then gave the Captain - “who did not understand the commotion around him” - therapeutic oxygen. The aeroplane reached FL380 and the First Officer took over as PF and engaged AP2 in place of AP1.

Shortly after this, a cabin PA resulted in one of the passengers identfying themselves as a medical doctor - a gastroenterologist - and they were invited onto the flight deck. After being briefed, she proceeded to check the Captain’s ‘vital signs’, which she assessed to be normal. She concluded that the Captain had experienced “a vasovagal episode” which required only “simple monitoring” and added that he should consult a doctor on arrival in Paris. The doctor was moved to Business Class so as to be closer to the flight deck and it was decided to continue the flight with one of the cabin crew occupying a supernumerary seat on the flight deck.

The Captain said he “wanted to rest in his seat again for a while” and asked the First Officer to wake him after half an hour. The First Officer reviewed the diversion possibilities and contacted Operations Control to obtain weather information for Guadeloupe, Martinique and Antigua and Barbuda. She was assisted by the crew of another Corsair flight also heading for Paris Orly which had recently departed Guadeloupe and was behind them who obtained updated weather information for Lajes.

When the Captain was woken as instructed, he responded normally and announced that he was going to rest for another 45 minutes. The First Officer woke him after that time and requested that the Chief Purser and the doctor return to the flight deck and examine him. His Blood Pressure had dropped to 100/60 and his oxygen level to 85%. The Chief Purser “removed the Captain’s epaulettes” and after administering oxygen, the doctor requested that the Captain should lie down in the forward galley but he refused “so as not to worry any passengers who might see him” and instead left his seat and laid himself down on the floor at the back of the flight deck. At this point, the flight was roughly midway between Martinique and Lajes, both around 1,200 nm away.

Shortly after this, the Captain’s ‘vital signs’ deteriorated further and the doctor carried out some neurological tests which found that he was “searching for words and showing signs of aphasia" (a language disorder caused by a pathology of the central nervous system). The First Officer contacted the other company flight to update them and ask them to get the latest Lajes weather as she intended to divert there. This crew then offered to liaise with Operations Control to keep them informed and relieve the First Officer of the obligation to do so which was accepted. This crew then informed Operations Control that according to the company Emergency Medical Services (EMS) agency, the situation was “quite serious” and added that there was no point in calling the flight direct as they would be acting as a relay. The Investigation was not able to explain this message about EMS contact as the First Officer stated that she had not made such a contact. 

The flight track annotated with key points. [Reproduced from the Official Report]

Two passengers who were neurologists and had not previously identified themselves as doctors then came to the forward galley and conferred with the gastroenterologist. The First Officer subsequently asked for a further medical report and the gastroenterologist explained that when she had seen the Captain showing signs of aphasia she began to think that the Captain may have suffered either a stroke or a Transient Ischemic Attack (TIA) and recommended a landing as soon as possible. The First Officer decided to divert to either Santa Maria or Lajes. The member of cabin crew who had remained on the flight deck volunteered to assist the First Officer and moved to the left pilot seat. The First Officer then explained the approach procedure to her and her role in reading the checklists.

After about an hour had elapsed since the Captain ceased his pilot duties, the First Officer sent a PAN message to the Santa Maria ATC via ACARS advising of her decision to divert. She then applied the applicable Special Procedure for in-flight contingencies in oceanic airspace by moving the flight track 5nm to the right and descending 500 feet. At the same time, the Chief Purser informed each cabin crew member individually of the situation. Shortly after this, Santa Maria ACC contacted the flight via SATCOM to ask for intentions to be specified and the First Officer, unable to remember the English word “stroke”, stated “brain bleed” and declared a MAYDAY.

After 4¼ hours airborne, the Chief Purser made a PA to inform passengers that due to a medical problem on board, “the Captain had decided to land in the Azores so that the patient could be taken care of by a medical team”. At the same time, the Captain got up and sat in a flight deck supernumerary crew seat. The remainder of the flight was without further event and the flight eventually landed on runway 15 at Lajes after an ILS approach an hour later. An apron vehicle was waiting to guide the aircraft to a parking position in the military zone and on reaching it, the doors opened and the emergency services attended and removed the Captain to hospital, where he “remained for several days”.

Discussion

The Captain explained to the Investigation that “he had been feeling unusually tired for several days”. Having operated the outbound sector without any untoward issues, the two pilots were rostered for a 48-hour rest period which was longer than the minimum. However, the Captain stated that he had been unable to sleep properly and had rarely left his hotel room due to feeling tired and having had “a bit of a headache”. However, he added that despite this, he had not at any time considered that his state of health might not be compatible with operating the two-pilot flight back to Paris.

The First Officer reported that she “got on well with the Captain” and said that his behaviour on the outbound flight had seemed “perfectly normal”. The Chief Purser said that she had seen the Captain on several occasions during the crew’s rest period in Martinique and that he had told her that “he had slept badly and had not managed to take a nap in the afternoon before the flight”.

In respect of the diagnosis of a suspected stroke, it was noted that not only must a stroke be considered an absolute medical emergency, a TIA must be considered as potentially just as serious. It was also noted that not all the signs of a stroke - fainting episodes, headaches, nausea, hot flushes, vomiting, weakness or numbness, loss of balance, neurological signs, impaired vision, slurred speech, paralysis of limbs or face, unexplained behaviour, and high blood pressure are necessarily present and are anyway not specific to a stroke so that identifying them only allows a stroke to be suspected rather than diagnosed. Similarly a TIA may present similar symptoms which disappear within a few minutes and in either case, “the urgency and need for appropriate assistance are the same because the risk of having a stroke in the short term is high” and “rapid medical assistance considerably improves the chances of survival and recovery”.

However, no relevant medical history or current treatment being received by the Captain was found and tests carried out during the Captain’s stay in hospital did not find any evidence of a stroke and “a TIA without after-effects” was suspected.

In respect of procedures relevant to all crew dealing with in flight medical emergencies, it was noted that the company OM ‘Part A’ and ‘Safety and Rescue Manual’ (SRM) included broadly complimentary guidance in respect of medical emergencies involving incapacitation with the former being primarily relevant to flight crew whereas the latter was intended for use by both flight and cabin crew. However, some differences between them were identified, the most relevant to the in-progress investigation being that whilst the Part ‘A’ included a requirement that the company’s EMS agency must be contacted via SATCOM in the event of partial or total incapacitation of any flight crew, the SRM was essentially concerned with passenger medical issues and had less strict wording in respect of contacting the EMS agency. Unlike the Part ‘A’, it was also noted that the SRM did not include reference to flight crew coordination with cabin crew using emergency phraseology or cover the possible assistance of a cabin crew member in the flight deck. However it did “describe the signs of unconsciousness as being when the victim does not respond or react normally to simple questions and commands, but is still breathing” and specified that this is a life-threatening situation and that the EMS “must always be alerted in addition to the call for a doctor, to assist and advise the crew”.

Finally, the Investigation noted that the ICAO ‘Manual of Civil Aviation’ Doc 8984 provides comprehensive guidance on the identification and potential operational consequences of in flight pilot incapacitation. It was noted to include the statement that “subtle incapacitations ... frequently partial in nature can be insidious because the affected pilot may look well and continue to operate but at a less than optimum level of performance (without being) aware of the problem or capable of rationally evaluating it”.

Contributory Factors were identified, in summary, as follows:

On the Captain’s decision to undertake the flight:

• The likelihood that the Captain's health had already begun to deteriorate before the flight.
• The fact that the Captain did not consider that his state of heath might not be compatible with operating the flight.
• The nature of subtle incapacitation and the difficulty which pilots may have on self assessing whether their state of health is compatible with a flying duty.

On the decision to continue the flight:

• When the Captain recovered from initially losing consciousness, the First Officer queried his intentions and there was no transfer of responsibility and the Captain decided to continue the flight. The First Officer did not object on a number of grounds:
  • the Captain had come around and was behaving normally;
  • the Captain was adamant that he could continue the flight; 
  • by reference to the Safety and Rescue Manual, the Chief Purser did not associate the symptoms observed with a life-threatening situation;
  • the diagnosis of a gastroenterologist on board based on his condition when initially examined that the Captain had probably suffered a “vasovagal episode” which only required “simple monitoring” provided he consulted a doctor on completion of the flight. This reassured the Chief Purser and the First Officer.
• The initial inability of the First Officer to get any reaction from the Captain when attempting to wake him up was not considered a sufficient warning sign that he was incapacitated, nor were his two subsequent requests for rest. This assessment “illustrates the difficulty in identifying and confirming a partial or temporary incapacitation and, consequently, in deciding on the transfer of a Captain’s duties as provided for in the aircraft operators’ procedures".

On Communication with Company Operations Control and Specialist Medical Support:

• The First Officer accepted an offer from the flight crew of a following company flight which was on a similar route to take over secondary communications in order to help reduce her workload. This crew erroneously understood that diagnosis of the Captain’s condition had been made in consultation with the designated Emergency Medical Services facility and therefore advised Operations Control accordingly. 
• The Operations Manual Part ‘A’ specified that in the event of physical incapacitation, even partial, of one of the flight crew members, Emergency Medical Services should be contacted but this requirement did not appear in the Safety and Rescue Manual, which only recommended calling Emergency Medical Services in the event of a life-threatening emergency, and without making a distinction when the patient is one of the pilots. Whilst the First Officer knew that she could seek advice from Emergency Medical Services, she did not consider doing so in the belief that it was only justified when no doctor responded to a passenger request to identify themselves. 

The First Officer’s Workload Management:

• Whilst the “cohesion and calm” of the cabin crew team assisted the First Officer in her management of the aircraft, the unservisability of the ACARS printer meant that she had to rely on relay with the other company aircraft to obtain weather for potential options.

Safety Action taken by Corsair as a result of the findings following the Serious Incident was noted as having included the following;

• Parts of the Safety and Rescue Manual have been amended to specify that in the event of partial or total incapacitation, or if there is any doubt as to the nature of the incapacitation of a crew member on board, the call to the Emergency Medical Services via SATCOM must be made by the flight crew, even if a doctor is on board. This update details the role of the Emergency Medical Services as a complement to the call for a possible doctor on board, while specifying the roles of each of them.
• An emergency medical sheet has been drawn up and attached to each emergency medical kit and to the Automated External Defibrillators (AED) equipping the aeroplane. It must be used by the cabin crew members or a doctor on board prior to a call to the Emergency Medical Services provider to collect information which will enable them to assess the situation.
• An internal communication to all aircrew was circulated to remind them of the mandatory nature of a call to the Emergency Medical Services provider even in cases where a doctor has been identified on board.

The Final Report was published in the definitive French version on 21 September 2023 and in English translation on 15 January 2024.

Related Articles

• Pilot Incapacitation
• Medical Emergencies - Guidance for Flight Crew
• Emergency Communications
• Diversion
• Flight Crew In-Seat Rest
• Pilot Workload
• Acceptable Deferred Defect
• Aircraft Communications, Addressing and Reporting System