A320, en-route, northern Italy, 2016

A320, en-route, northern Italy, 2016


On 15 August 2016, the cognitive condition of an Airbus A320 Captain deteriorated en-route to Riga and he assigned all flight tasks to the First Officer. When his condition deteriorated further, an off duty company First Officer travelling as a passenger was invited to occupy the flight deck supernumerary crew seat to assist. Once descent had commenced, the Captain and assisting First Officer swapped seats and the flight was thereafter completed without any further significant event. The Investigation concluded that the Captain’s serious physical and mental exhaustion had been the result of the combined effect of chronic fatigue and stress.

Event Details
Event Type
Flight Conditions
Flight Details
Type of Flight
Public Transport (Passenger)
Intended Destination
Take-off Commenced
Flight Airborne
Flight Completed
Phase of Flight
over northern Italy
CVR overwritten
Fatigue, Flight Crew Incapacitation
Flight Crew Incapacitation
Damage or injury
Non-aircraft damage
Non-occupant Casualties
Off Airport Landing
Causal Factor Group(s)
Aircraft Operation
Safety Recommendation(s)
None Made
Investigation Type


On 15 August 2016, an Airbus A320 (HA-LPN) being operated by Wizz Air Hungary on a scheduled international passenger flight from Barcelona to Riga was in the cruise over northern Italy when the Captain’s cognitive condition began to deteriorate and he assigned all flight tasks to the First Officer. When his condition deteriorated further, a company First Officer travelling as one of the 182 passengers was invited to occupy the flight deck supernumerary crew to assist and this pilot subsequently swapped seats with the Captain for the remainder of the flight which was completed without further event. 


Following notification of the event to the Hungarian Transportation Safety Bureau by the aircraft operator late on the following day, a Serious Incident Investigation was opened. It was noted that relevant data on the CVR had been overwritten. 

The 35 year-old Captain, who had joined Wizz Air as a direct entry Captain and was a Belgian national, had initially acted as PF on the investigated flight. He had a total of 8,060 hours flying experience on all aircraft types. The 33 year-old First Officer, who was a French national holding a CPL (Commercial Pilot Licence), which was a licence that did not permit him to fly in command of an A320, had a total of 3,486 hours flying experience of which almost all were on type.

What happened

On the day concerned, the flight crew involved were rostered for a return flight from Riga to Barcelona. During the crew’s pre-flight preparation for the first of these flights, it was reported that the Captain’s state of health was discussed, but that “he had said that he felt fully fit to perform his duties”. Due to operational reasons not connected with the flight crew, this outbound flight departed an hour late which, in combination with “unfavourable, stormy weather” forecast around their ETA at Riga, meant that the crew recognised it might be difficult to get the return flight back into Riga before it closed for the night. 

The outbound flight was completed uneventfully but the subsequent turnround “placed considerable stress on the Captain” when the return departure was reportedly further delayed by several operational issues including “clarification of differences of views with the ground handling personnel” and the expiry of the initially submitted navigational FPL. Once the flight was able to taxi for takeoff, “the Captain’s health problems became visible to other crew members” but when the First Officer asked whether he was alright, he replied that he “felt tense but fit to fly”.

The 3½ hour return flight initially proceeded uneventfully but in the cruise over northern Italy, “the Captain’s health problems worsened, which, as he (subsequently) said, manifested in a tense mood, intense heartbeat, and mood swings”. Soon after this, he “began to complain of sickness and panic attacks” and although the idea of an emergency landing in Milan was dismissed, the Captain then “assigned all flight-related tasks” to the First Officer. However, “despite a thirty-minute rest, the Captain’s symptoms got even worse” and so another Wizz Air First Officer travelling as a passenger, was invited onto the flight deck to assist the operating crew from the supernumerary crew seat. 

When, over the next 90 minutes or so, the Captain’s condition had still not improved, he decided, just after the descent into Riga had been commenced, to swap seats with the assisting First Officer who then continued in the Captains seat for the remainder of the flight. A PAN PAN message was transmitted to ATC to advise of the situation and the rest of the descent, and the approach to and a night landing on runway 18 at Riga with no adverse weather conditions was completed twenty minutes ahead of the airport closing time. Once the aircraft had been shut down on the assigned parking stand, “a mobile health service unit examined the Captain, but found no reason for transporting him to the hospital or performing immediate medical care”.

The Captain’s Incapacitation

A specialist examination of the Captain which was performed “abroad” after the event found that he was suffering from fatigue due to long-lasting stress”. The Captain himself reported that “several stressful events” in the period prior to the investigated flight had “contributed to his physical and mental exhaustion”. He identified these events as “multiple changes of base airport, an adverse change in his private life, several bird strike incidents in the previous months and a flight with a malfunctioning weather radar in stormy weather a few weeks earlier”.

He also mentioned “an emotionally charged conflict in the previous month” which arose after he had to divert to an alternate airport after missing the closing time of Riga Airport. He considered that his condition was aggravated by events on the day of the occurrence “in particular the risk of a late arrival at Riga, which had previously been a very unpleasant experience” on a day when the usual destination alternate, Vilnius, would not have been available meaning that any diversion would have been a much longer one to Helsinki.

It was noted that after the investigated flight, the Captain had not been rostered to fly for a long time and had finally left his employment with Wizz Air.

Wizz Air and Pilot Fatigue

It was noted that almost a year prior to the investigated event, the airline had begun to establish a department to manage the risk arising from fatigue of flight crews” but that this establishment was still incomplete. It was noted that the main responsibilities of this new department were intended to be:

  • raising awareness of the subject through training and regular information for flight crew, their managers and crew rostering personnel,
  • gathering information on exhaustion or imminent danger of exhaustion among flight crew,
  • assessing and evaluating the extent and evolution of the risk arising from exhaustion,
  • developing proposals to reduce these risks,
  • following up and monitoring the implementation and impact of the proposals adopted.

  It was noted that, as the Investigation was being completed some 4½ years after the event had occurred, the computerised flight crew rostering output was still being checked manually against a hard copy “crew member fatigue module”

Organisational Culture

The Investigation noted that “the fatigue-related organisational culture of flight crews is contradictory and difficult to quantify”. It was also observed that whilst it is well known that flight crew fatigue poses a threat to aviation safety, “the assessment of the risk it entails for a crew member and its meaning is not a simple task (since) on the one hand, it may conflict with the image perceived by the person of his/her own physical condition and endurance and on the other (induce) anxiety about the real or perceived danger of reprisal from the airline” which may mitigate against the open admission of fatigue. 

It was further observed that ensuring “the highest possible anonymity” of fatigue reports and credible communication in relation to them may help to overcome those difficulties. In the case of Wizz Air, it was found that over the four year period since the investigated event, there had been a continuing but erratic upward trend in fatigue reporting which it was speculated “may indicate the gradual acceptance of the system (as) an important pre-requisite for effective recognition and management of fatigue and fatigue-related problems”.

An Overview of the Findings

It was clear that during the weeks and months preceding the investigated event, “the life of the Captain concerned had contained a number of events which increased his fatigue to a level exceeding the usual and was also fairly demanding for him mentally”. These circumstances had interfered with a normal off duty resting and sleeping regime beyond the normal challenges of the irregular working hours typical of a professional airline pilot. Although the Captain recognised “the worsening symptoms of his fatigue and stress”, he continued to believe that they were not compromising his fitness and so had not considered it necessary to inform his colleagues or the airline about his condition. 

It was considered that when the Captain had discussed his condition with the First Officer before beginning the day's flying and stated that he was fully fit to perform his duties, the situation of the junior pilot is potentially difficult. Only clearly-evident incapacitation of a Captain removes his authority and “in this case, the Captain was far from incapacitated at the time of the departure” so even if the First Officer had foreseen what might occur, there was no way to intervene. A similar situation occurred on the ground in Barcelona where when the First Officer remarked about the Captain’s condition, the Captain “deflected the issue”. However, it was accepted that “when the Captain’s condition actually turned critical on the way back to Riga, the crew, including the Captain, acted in a constructive and responsible manner”.

It was noted that it is impossible for the applicable regulatory requirements in relation to the fitness of pilots to cover all possible situations so the attention of individual aircraft operators to this matter is essential and “as flight crews perform their work and make their decisions in a fairly autonomous manner, workplace culture is also an important element of safety”

The Cause of the Serious Incident was determined as the Captain’s serious physical and mental exhaustion which had been the result of the combined effect of chronic fatigue and stress.

Two Contributory Factors were also formally identified:

  • The Captain had not properly assessed his physical and mental condition. 
  • The other member(s) of a flight crew have no means to override a Captain’s decision on his own physical and/or mental condition until he/she becomes incapacitated.

The Final Report was finalised on 24 March 2021 and subsequently published in both English translation and in the definitive Hungarian language version. No Safety Recommendations were made.

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