Cognitive Decision Making Models & Aviation


Decision making in aviation is a widely discussed subject and a lot of research has been done to understand the best process for making a decision that provide the best outcome for any given situation. There are plenty of practical models that are actively used by pilots on a daily basis (e.g. Models such as SAFE, GRADE, FATE & DECIDE), this article aims to shed light into the mental processes of decision making with emphasis on Naturalistic Decision Making and its associated cognitive models.

Decision Making: Is It a Mental Process?

For most of us a decision is just another choice we make in doing something or achieving a goal. From an aviation perspective this can be the course of action a pilot decides to take in the event of an emergency or even in normal operation of his or her flight. A more analytical definition of decision making according to McGrew & Wilson (1982) is, “the end state of a much more dynamic process which is labelled ‘decision making’. It is conceived of a process since it consists of a series of linked stages of activity, not simply a discrete action”. From this definition we can understand that decision making involves certain mental processes that people follow before deciding on a course of action. These mental processes can be simply understood as cognitive models

Naturalistic Decision Making (NDM)

Naturalistic decision making as defined in Wickens, Gordon & Liu (1998) is, “the way people use their experience to make decisions in field settings”. In the real world environment, tasks that involves decision making tend to have the following characteristics:

  • Ill structured problems.
  • Uncertain, Dynamic environment.
  • Information-rich environments where situational cues may change rapidly.
  • Cognitive processing that proceeds in iterative action/feedback loops.
  • Multiple shifting and/ or competing individual and organised goals.
  • Time constraints or time stress
  • High risk
  • Multiple persons somehow involved in the decision.

(Wickens et al 1998. P.196-197).

Mental Models are derived based on the above characteristics.

Rasmussen’s Skill, Rule & Knowledge (SRK) Model of Decision Making

SRK Model (image embedded from Nippon on 10 September 2011)

This model describes 3 different levels of cognitive activity during task performance and decision making.

1. Skill Based Level: Performance and decision making is at the subconscious level and is more of an automatic response to a particular situation. People who usually make skill based decisions are very experienced with the task at hand.

2. Rule Based Level: People will operate on this level when they are familiar enough with the task but do not have enough experience and will look for cues or rules that they may recognise from past experience to make a decision.

3. Knowledge Based Level: When the task at hand is novel and when people do not have any rules stored from past experiences, people will resort to analytical processing using conceptual information which involves problem definition, solution generation and determining the best course of action or planning before making a decision.
(Wickens et al., 1998, p.198)

According to this model, a person may operate in one, two or even all three levels depending on the task and how experienced the person is.

Recognition-Primed Decision (RPD) Model

RPD Model (image embedded from on 10 September 2011)

As described in Simpson (2001) this model has 3 main steps:

1. Situation recognition: Which involves looking for familiar patterns or experiences.
2. Serial option evaluation: Which involves looking for relevant cues, provide expectancies, identify plausible goals, and suggest typical types of reactions.
3. Mental simulation: To see if the chosen outcome will be workable or not before any action is taken

Klein (2008) goes on to state that, “the RPD model is a blend of intuition and analysis. The pattern matching is the intuitive part, and the mental simulation is the conscious, deliberate, and analytical part”.

Are They Relevant to Aviation?

When operating an aircraft pilots are constantly faced with dynamic environments where they may be challenged with multiple ill structured problems under high stress and possibly high risk conditions. Add to that the time constraints and the modern aviator is now faced with a few challenges when it comes to decision making. According to Simpson 2001, “In such naturalistic environments, intuitive styles of decision making (such as NDM) are more appropriate”. However, there are a few things that need to be understood regarding these Naturalistic Decision Making Models.

1. RPD model will be more useful for expert pilots as it requires the use of previous experiences and pattern recognition to make decisions. Novice pilots or ab-initio pilots are at a disadvantage here as their pattern recognition repertoire will be very limited due to their inexperience.

2. SRK model can be used by both novice and expert pilots although the level to which they can use the model will once again be limited to their experience. For example trainee pilots will only be able to operate in the “Knowledge” based level of decision making whilst commercial or professional pilots may vary from Rule Based’ level to Skill Based’ level.

1. McGrew, A.G., & Wilson, M.J. (1982). Decision Making: Approaches and Analysis. Manchester: Manchester University Press.
2. Gordon, S.E., Liu, Y., & Wickens, C.D. (1998). An Introduction to Human Factors Engineering. New York, USA: Longman.
3. Klein, G. (2008). Naturalistic Decision Making. Human Factors Vol.50 (3) 456-460.
4. Simpson, P.A. (2001). Naturalistic Decision Making in Aviation Environments. Air Operations Division Aeronautical and Maritime Research Laboratory. Victoria, Australia. Retrieved September 9, 2011 from
5. Decision Making (n.d.). Retrieved September 9, 2011 from
6. SRK Model Picture (n.d.). Retrieved September 9, 2011 from

Want to know more?

Decision Making In Aviation
Introduction to decision making, factors affecting decision making.
Aeronautical Decision Making
Teaching decision making.
Decision Making Models
A good introduction to practical decision making odels.
Cognitive Perspective
A very basic introduction to the cognitive perspective of human performance.

Contributors to this page

Authors / Editors

Mishma HameedMishma Hameed

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