More is always better?
Is an additional flight crew member on the flight deck conducive to operational flight safety?

Challenging the dogma that an additional pilot on the flight deck always contributes to the safe conduct of a flight


Airlines frequently augment two-person flight crews with additional flight crew members (AFCMs). This is primarily done for the purpose of extending duty and flight time limitations, But also for checking and training activity, or even deadhead transportation. Common wisdom has it that these extra pilots will improve the safety of the flight when occupying observer seats on the flight deck, by offering an additional cross-check on the progress of the flight. This practice is due to an underlying assumption that extra crew member means more safety. However, the very presence of AFCMs on the flight deck introduces psychological effects upon the flight crew at the controls, with a demonstrable impact on their performance. This gives rise to hazards which have not been addressed by the industry to date. This paper identifies those hazards and others, calling on the industry and its regulating bodies to research and consider the human performance factors behind the presence of AFCMs on the flight deck.


In recent months, at least three investigation reports were published, in which the investigators commented regarding the role of Additional Flight Crew Member(s) (AFCM) in the cockpit (pilots in addition to those at the controls) and how they could have helped to prevent the incidents from occurring. This paper will suggest that the presence of AFCM in the cockpit does not necessarily result in an increased level of safety, but rather the contrary – that their presence might indeed be a contributing factor to the occurrence of incidents in the first place. In a recent report by the French BEA , the PIC states that he had to declare, “Everyone silent. I am the only one giving orders”.

The clear benefits of AFCM on the flight deck

  1. Having additional people in the cockpit might prevent the occasional “routine” violation – pilots tend to avoid bending the rules when there is an audience.
  2. The additional crew members’ years of experience could prove beneficial to the crew at the controls, especially on long-haul aircraft where pilots lack opportunities to gain valuable experience outside of cruise flight.
  3. On the other side of the equation, the additional crew members not at the control also stand to benefit; being present on the flight deck even when not at the controls could contribute to the total experience of pilots in the company. Long-haul pilots simply do not have the opportunity to experience as many takeoffs, approaches and landings as short-haul pilots. This is true especially during periods of low traffic such as off-season and challenging times such as the current COVID-19 pandemic.
  4. “An extra set of eyes” – this is the default assumption for many operators and pilots alike. Common wisdom has it that an additional pilot in the cockpit free from any obligatory tasks and responsibilities has the available attention and resources to serve as a “safety officer”. He or she is in a position to pay more attention and to identify threats and prevent/correct errors made by the operating crew. This appears to be the most obvious contribution of the AFCM to flight safety; however, as will be explained, this paper asserts that this assumption must be examined.

The clear detriments of AFCM on the flight deck

  1. Distractions – there is no question regarding the threats that distractions pose to the safe conduct of a flight. Having an AFCM in the cockpit increases the number of potential distractions; from small talk to the occasional smartphone notification, to disruption in the normal flow of the SOP and beyond.
  2. Stage fright – some pilots will perform flawlessly under conditions such as fire/smoke in the cockpit or runaway stabilizer, but will freeze in the presence of an audience. Human nature being what it is, the nature and intensity of this effect varies widely amongst the pilot population.[1]
  3. No standard – there are no ICAO SARPs or industry guidelines regarding AFCMs. Operators may or may not have guidance for AFCMs, but there is often a lack of clarity regarding what is expected of them. Specific examples lacking clarity or standards include but are not limited to:
  • How can AFCMs avoid disrupting the normal work in the cockpit?
  • When and how should they speak up?
  • Are they required to follow the taxi clearance and progress with the taxi chart open?
  • Must they wear the observer headphones?
  • Are they to communicate with the cabin crew in an emergency?
  • Can or should AFCMs perform other tasks such as PA announcements; review of the aircraft technical logbook; or walk-around inspections?
  1. Even if there is company guidance for the AFCM to serve as an extra cross-check on the operating crew, the AFCM will naturally be drawn to the actions performed by the crew rather than their omissions.
  2. No training – most airlines do not provide any training in managing a flight with three or four pilots in the cockpit handling an emergency or even in a normal LOFT scenario.

That being said, we must bear in mind that the choice of having AFCM on the flight deck is not black and white, nor always ours to make. There are cases when the AFCM is required to be in the cockpit. Examples include:  Line checks, IOE, LIFUS, NAA supervision, LOSA or simply because there are no other free seats in the cabin. The COVID-19 pandemic introduced a new reason, when it became necessary to isolate the crew from potentially infected passengers.

The last ten disturbing incidents we investigated involved cockpits with more than the minimum required crew. These incidents include but are not limited to:

  • Takeoffs with significantly erroneous takeoff parameters.
  • Loss of airspeed on go-around (107 knots) almost resulting in a stall.
  • EGPWS warning on approach and another EGPWS warning after a missed approach.
  • Extreme unstable approach.
  • Descending to 800 feet below class B airspace without clearance.


The psychological – sociological point of view

Social facilitation/inhibition

Social facilitation is the change in behavior and action of an individual in the presence of an audience[2]. Some thrive and some have stage fright. The scientific studies, though, are very clear: a crew member will usually perform better in the presence of an observer/supervisor if the operation is normal. However, there will be a degradation of performance when the pilots are required to handle abnormal or emergency situations  in the presence of an AFCM or to a lesser extent in the presence of another kind of observer.

There is room to discuss the various crew compositions. Some airlines utilize two captains and a first officer; some utilize some other combination of captains, first officer, senior first officers, cruise pilots, etc. . The COVID-19 pandemic even created a situation where crew compositions consisting of s three line-check airmen serving as a flight crew could be considered normal.

It should come as no surprise that the magnitude of adverse social loafing depends not only on the pilot at the controls but also on the rank and personality of the AFCM.

A first officer in the observer seat adds less pressure to the cockpit than a captain or check airman and will usually be more reluctant to comment, while a captain or check airman in the observer seat is more likely to be perceived as intimidating, regardless of their personality and training. This is solely based on the perception of the pilots at the controls regardless of the AFCM’s actual behavior or personality. It follows that  a more assertive and less disciplined captain in the observer seat will exacerbate their negative influence on the operating crew. It must be stressed that under-performance during stressful events is to be expected regardless of who is occupying the observer seat.

Social loafing – complacency

Social loafing in this context is the tendency of a pilot  to lower one’s guard when several  proficient pilots are present in the cockpit. Social loafing is somewhat different than complacency as it is induced by the objective fact that there is an “extra pair of eyes” in the cockpit. The feeling of “there are so many people here – someone is sure to say something if things go awry” leads each one of the pilots to become  slightly less vigilant.

Add to that a young first officer paired with a senior captain, and it is only natural that the junior pilot will be somewhat reserved.  Much effort and CRM training is put into fighting this natural tendency with impressive results, yet without one hundred percent success.

The sense of being under the capable wings of a more experienced captain is very natural. This is true, even more so, when there is another pilot in the cockpit, leading a junior first officer to assume subconsciously that, “these two will get me out of trouble no matter what”.

Various cultural  differences will induce amplification or reduction of the discussed effects. These include cockpit gradient, “who is right vs. what is right”, attitudes towards personal space and respect, and so forth.

We will not elaborate on distractions or the lack of standards and training in three or four-men cockpits, as the detrimental effect of those factors is obvious. .

Threat and Error Management Model Application

Is having an extra pilot a mitigation or a threat?

We believe that a good theoretical model to analyze the subject is Threat and Error management (TEM). There is an unspoken understanding among crews that the goal of zero accidents and zero major events can be achieved by aiming at zero mistakes (errors) – small or large. We believe this notion to be false. It causes the pilots undue stress, and it causes them to be too quick on the trigger to point out other crewmembers’ minor errors  which would almost certainly have been noticed and resolved moments later. If the AFCM lacks patience and does not allow the operating crew some time to fix things themselves, it causes distractions and stops the normal flow of SOP and communications. This in turn causes a “flat” approach to managing errors during the flight. i.e., everything is of the same importance. The crew will take the attitude that if they miss something, although it is probably very small, it might be big – thus treating all errors as equal when  in reality that is not the case and prioritization is in order. To quote Sindro from The Incredibles – “If everybody is a hero, then nobody is”.

Risk management Matrix

If we build a risk management matrix, it is easy to see that the presence of AFCM on the flight deck carries inherent risks with a high probability of occurence. In a broader sense, the AFCM who is on board the airplane mainly to mitigate various risks associated with fatigue in order to allow long-haul operations, introduces as a side effect new risks that most operators fail to identify and mitigate.

The straightforward result of such a matrix leads to the conclusion that the AFCM’s role is not to mitigate any risk that a two-pilot flight crew can’t handle on their own. All two-pilot crews are fully qualified to operate a two-pilot cockpit, and all of the relevant risks have already been addressed and mitigated using SOP, training as well as technical and non-technical skills. The practical reality is that rather than mitigating any risk, the AFCM creates new hazards for which the best mitigation is to simply exclude AFCMs from the cockpit altogether.

To summarize the TEM model view & the risk management matrix, the mitigation of minor lapses and slips comes at the cost of distractions and missed significant events. When referencing the “swiss cheese model”, having AFCM in the cockpit might make the holes in the first slice smaller at the cost of making the holes in the next slices bigger.

Competency-based Analysis View:

Looking at  the nine ICAO competencies we conclude that AFCM on the flight deck affects the pilots at the controls in the following ways:

  • Knowledge, manual & automatic flight – there is a negligible influence (if any) on the Knowledge, manual & automatic flight skills of the operating crew.
  • Application of knowledge – there should be a positive influence in the short-term application of knowledge, accompanied by the risk of distractions[3]. We expect to see less deviations from normal SOPs and better detection of lapses and slips.
  • Workload Management – AFCM have predominantly a negative influence on Workload Management, particularly when quick actions are required. One more “thing” in the cockpit to worry about (or maybe impress? or not to disappoint?) increases the workload by definition. AFCMs might be beneficial in performing tasks that are time consuming but not time sensitive, such as talking to the company or to the passengers over the PA while the operating crew is focused on more important tasks.
  • Situational awareness – the AFCM have a dual influence on situational awareness – occasionally the AFCM will help, but in other instances they will disrupt the crew’s natural equilibrium and cause them to miss other, perhaps more important information. In addition, this influence is difficult to predict, as it largely depends on the timing, intonation and personalities of the individuals involved.
  • Communications – AFCM influence is mostly negative. Pilots are trained in standard phraseology, task-sharing and flight-flow based on a two-pilot
  • Leadership and teamwork – Naturally this issue depends to a large extent on the roles and personalities of the pilots involvedץ For instance, if the Pilot Flying is the first officer at at a company where the policy is to have the FO lead, their leadership will likely be degraded by having an additional captain in the cockpit — especially in the case of one with a dominant disposition. Teamwork might also be impaired as pilots are not trained in the art of three-man cockpit operation anymore.
  • Problem solving and decision making – There is a big difference between problems and decisions that must be made immediately versus situations where time is available. There is an obvious benefit in consulting an additional pilot with additional years of experience. However, this is not the case when quick or instinctive action is required. In these instances, an AFCM tends to usually disrupt the effective training-based handling of problems.

AFCM versus other observers

It should be noted that the potentially negative effects of AFCM on the flight crew’s performance can be even worse than when a person who is not a qualified pilot occupies the observer seat. Non-pilot observers are normally trained (or at least briefed) to avoid disturbing the flight crew, whereas AFCM tend to

The case against the theory laid down in this article

The main case to be made against the argument advanced in this paper is the benefit of having a free person with the task of serving as a “safety officer” in the cockpit. Many pilots argue that they are fully capable of managing and containing the distractions created by the AFCM. There is a school of thought amongst many pilots claiming that the benefit of detecting missteps, omissions, and mistakes as soon as they happen is of immeasurable gain. They usually tend to consider social loafing or social facilitation to be less dangerous than expressed in this paper. This argument, though true for some pilots to be sure, must be tempered against pilots’ tendency to overestimate their abilities and the general lack of awareness regarding the social facilitation effects. It must also be stressed that differences in personality, individual upbringing, and culture make this argument almost impossible to hold true for all (or even most) pilots in all situations.

The Legal Aspect

ICAOs Annex 2 to the Chicago convention establishes that only the pilot-in-command has final authority and responsibility for the safe conduct of the flight. This principle has been adopted by regulators across the board.

The question must be asked whether operators demanding the presence of AFCM in the cockpit impair the PIC’s ability to fulfill his/her legal duties, responsibilities, and accountability.

There appears to be a rather clear distinction between the ICAO and CAA air-laws and the approach operators and investigation checking compliance with the operator’s manual are taking.

Settling the contradiction between the will to be present on the flight deck and the downside of disturbing the PIC should be carefully researched by academia, regulators, and industry. It is our belief that:

  • Operators should never hold an AFCM as accountable;
  • Operators should act to minimize the negative influence of an AFCM on the pilot-in-command;
  • Operators should not assume that by adding another pilot to the cockpit they are increasing the level of safety;
  • Operators that demand accountability from relief pilots are more than likely encouraging behaviors that are less than optimal for best results. Such a policy needs to be revisited, as our experience shows that the downside is not negligible.

Conclusion and Recommendations

We believe that the presence of  AFCM on the flight deck is less straightforward  than it seems. While having some benefits and in extreme cases of a dysfunctional crew even the potential to avoid an accident, an AFCM might not only pose a threat  to the successful and safe conduct of a flight, but may on rare occasions lead the pilots at the controls to miss a significant threat or  to mishandle errors, leading to an incident/accident.

As this is a common underlying assumption in the SOP or AFM of many airlines, this paper makes the following recommendations:

  • Raise awareness amongst pilots of the benefits and pitfalls of having AFCMs in the cockpit.
    • Remember: the primary reason for augmenting flight crews is to manage fatigue.
    • Always prefer extra rest to any other task.
  • Raise awareness amongst relief pilots of the negative effects (sometimes hidden) they might have on the safety of the flight if present on the flight deck.
  • If AFCMs are to be present on the flight deck, preference should be given to first officers rather than captains.
  • Operators should implement a clear policy on the presence of AFCMs in the cockpit during critical phases of flight, including Dos and Don’ts while on the flight deck (see Appendix for an example policy as an example).
  • We urge organizations such as ICAO, IATA, EASA, FAA, Flight Safety Foundation, NASA, and the NTSB to conduct research into the issue so that industry will be able to formulate an evidence-based position, rather than the current stand which ranges from having no basis at all, to gut feeling and emotion in the best case.
  • Urge Human Performance specialists to conduct research and develop recommendations and guidance materials regarding the subject matter.



Captain Hovav Ben David, former Chief Pilot and Director of Flight Operations, El Al Israel Airlines

Captain Itay Givol, former Flight Crew Training Manager, El Al Israel Airlines



Mr Moshe Greenberg

Captain Avraham (Rami) Liebling

Appendix 1 – Suggested CRM Policy in an Augmented Crew in the cockpit

Only two flight crew members are required on the flight deck, regardless of the crew composition. In an augmented crew, although additional flight crew member(s) on the flight deck may have advantages, there are also disadvantages that usually outweigh the advantages (see discussion below). Therefore, their presence is usually not encouraged. However, they may be present on the flight deck due to lack of cabin seats, the PIC’s request, or during IOE or Line Checks, etc. Presence of additional flight crew members on the flight deck should be coordinated by the crew and is subject to the PIC’s discretion.

While on the flight deck during critical phases, the sterile flight deck shall be observed. Any additional crew member(s) shall not disturb, distract, or interfere with the operating crew. They should only comment if they notice a critical safety situation which was not observed by the pilots at the controls in due time and is likely to lead to a serious incident or accident.

Although a third pilot on the flight deck can provide an extra “set of eyes” not preoccupied with operating the aircraft, crewmembers at the controls must be aware of the negative impact additional crew members in the cockpit might have and should act as if they are alone in the cockpit.

Human performance research shows that extra crew members on the flight deck can cause the following:

  • Awareness of being watched which can actually cause worse performance on complicated tasks (“Social Facilitation”);
  • Subconsciously creates a fear of speaking “before an audience” or doubting one’s self (“if nobody else noticed what I’m seeing, I must be wrong”). This can lead to failure to call anomalies, state an unexpected event, or ask for clarification (“Social Inhibition”);
  • Subconsciously creates a mindset of “there are so many pilots here that someone will see if something goes wrong. I can lower my guard”. (Complacency/ “Social Loafing”).

Notwithstanding the above, during FOR-DEC, additional experience may prove useful. Two-man cockpit CRM principles shall first be observed and only after they have been followed, may the additional crew member(s) be consulted.



Leave a Reply