Situational awareness as it is manifested in the mind is like information presented on a whiteboard. Decision making is using that information to choose a course of action. In this post I will review available literature on the processes of situational awareness and decision making, and their interconnected nature, and present textual illustrations of the models discussed. I have modified this post from it’s original format to better fit the an appropriate blog post format.
Situational awareness is a critical factor in decision making across many disciplines (Endsley, 2006) and it affects a pilot’s ability to make effective decisions (Jones, 2006). It appears that the path from detection of a stimulus to a completed decision begins with sensual perception (Endsley, 1995); it is cataloged in short term memory and reviewed by long term memory. Processing continues as the set of perceptions are checked against a mental model, schema, expectations and current goals, in top down processing or bottom up processing in a data driven scenario (Bolte, et al., 2003). The information now available in the pilot’s mind becomes the basis for a choice which is then made and acted upon by the pilot. This process is not static; it must be continuous as a dynamic situation is composed of changing stimuli over time, (Endsley, 1995) requiring new decisions and subsequent actions along the way. This post, will briefly discuss situational awareness, decision making, and the interaction of situational awareness with decision making based on a focused review of the scholarly literature available at the time of the original writing, 2010.
A Review of Situational Awareness
The most common model found in the literature search of situational awareness was formulated by Mica Endsley (1995). He defined situational awareness as: “the perception of the elements in the environment within a volume of time and space, the comprehension of their meaning, and the projection of their status in the near future.” He further explained his model as being composed of three components of situational awareness moving from the basic perceptions a pilot is exposed to (level 1), through the comprehension of what those elements mean, and how they interact (level 2); and finally to the ability of a pilot to apply level 1 and level 2 information to the future (level 3) (Endsley, 1995).
In level 1, “perceiving the elements of the environment” (Endsley, 1995) a pilot will take in large amounts of raw information. It is my contention that the information the pilot acknowledges from all of the information available is guided by the phase of flight they are currently in, or the goal of that phase. For example, if a pilot is about to take off, they will conduct routine observations such as looking at the windsock, checking the placement of the rudder pedals, evaluating the status of the engines, and assessing a radio call from the tower. The pilot may guide his/her attention to the takeoff “switchology” to confirm he/she is ready to fly the departure. The pilot will assess the traffic pattern and look for other aircraft. All of these perceptions discussed would apply to a takeoff scenario, and they build the raw data for use in level 2 situational awareness.
In level 2, “comprehension of the current situation” (Endsley, 1995) the pilot from our example will add the data elements from level 1 together and create a mental picture of the current state of his/her aircraft and environment. The mental conversation may go something like this: “The windsock is pointing left to right, so I will need to correct with right rudder and left aileron. The engine is operating in the green so I will be able to apply takeoff power. The tower has cleared me to take off, so I am free to apply takeoff power when I am ready. One last check on the transponder, lights, and NAVAIDs to make sure they are set up correctly and my takeoff path is clear. I am ready for takeoff.” With each piece of data, the pilot recognized an effect associated with that data, or how a given piece of data was related to another. The pilot, recognizing how all of the data interacts is now mentally primed for level 3 situational awareness.
In level 3, “projection of future status”, (Endsley, 1995) the pilot will integrate level 1 and level 2 information with information from experience, a mental model or a schema that will guide their expectations of the near future (Endsley, 1995). The result of the cognitive effort may play in the pilot’s mind thus: “I am ready for takeoff; I have been cleared to do so. After I apply power the aircraft will begin to move, at 80 knots I will check the applicable instruments as needed. I will rotate the aircraft at the appropriate speed, climbing into the cleared airspace. I expect all to go as planned, but based on my training and experience I will be prepared for a dynamic change from my expectations.”
Being prepared for changes also implies the function of data-driven processing or bottom-up processing wheras the pilot, with the goal of taking off, still monitors data from the environment that may lead to a change in the current goal (Bolte, et al., 2003). For example, if there is data that then engine might not be functioning correctly, the pilot may change their goal from taking off, to aborting the takeoff.
Figure 1 was imported from Endsley’s (1995) article: Toward a theory of situational awareness, to illustrate the three levels of situational awareness he describes.
Figure 1. This figure represents Endsley’s (1995) basic structure of situational awareness, but also illustrates the place of decision making and actions in the overall process. Decision making will be discussed later in this work.
Another model of situation awareness was presented by Stanton (2006) but explained in more detail by Adams et al. (1995). It is called the perceptual cycle. Figure 2 was imported from Stanton’s (2006) article and illustrates the theory. For the purposes of explanation, consider the takeoff scenario from the previous situational awareness model above.
Our pilot, having been given clearance to takeoff perceives that clearance via the function of perceptual exploration. The following locomotion or action would be to apply takeoff power. Sampling occurs as the aircraft moves through time and the environment as the pilot processes that new information. The new information modifies his cognitive map of his/her environment, the pilot compares that information to a schema of the present environment to direct further action, and in this case he/she may choose to continue the takeoff roll. The perceptual cycle persist in a process that continually updates the pilot’s situational awareness and subsequently his/her resulting actions.
- Figure 2. The perceptual cycle.
Situational awareness research continues, and it should, because of the potential to reduce human factors related errors in flight. Currently, the research appears to be taking two paths that lead to positive contributions to situational awareness, but are based on different paradigms. One line of research is based on situational awareness as a product, and the other line is based on situational awareness as a process (Durso & Sethumadhavan, 2008). The product based line evaluates situational awareness by the end result, and the process based line is concerned with the cognitive process that leads to the existence of situational awareness (Durso & Sethumadhavan, 2008). On a side note, situational awareness has been researched by many disciplines, but it appears that there is no single unifying theory on the topic. The next portion of this post identifies the component of decision making.
A Review of Aeronautical Decision Making
Situational awareness and decision making appear to go hand in hand but are recognized as different components of the cognitive process (Endsley, 1995). As Jones (2006) points out, people with excellent situational awareness can make poor decisions and people with excellent decision making can have poor situational awareness. The point Jones (2006) makes illustrates the differences in situational awareness and decision making; and respects the concept that they are two separate elements in the cognitive processes involved in flying.
According to the Federal Aviation Administration (FAA), “Aeronautical decision making is a systematic approach to the mental process used by aircraft pilots to consistently determine the best course of action in response to a given set of circumstances” (FAA, 1991). In light of the definition provided, one might question the nature of the “systematic approach” and the “mental process”. The FAA circular is curiously incomplete on a proposed systematic approach and on the mental process it references. Based on the researcher’s flying experience, mnemonics are a good example of a widely used aid to systematic decision making.
To illustrate the decision making process as exercised using the DECIDE mnemonic (Adrion & Jensen, 1988) we return to our takeoff scenario from the situational awareness portion of this paper.
The pilot detects a change; he/she has been cleared for takeoff. He/she estimates the need to respond to that change, which is relatively simple; he/she has been cleared to take off, and there is no further reason or purpose to occupy the runway, so the need to respond to the change is evident. The choices available are to apply power and take off, or to not, and advise the tower. The pilot in this scenario will choose the desirable outcome of taking off. The pilot identifies the actions that will result in takeoff which includes responding to the tower, completing the takeoff checklist and applying power. After the identification step is complete, the pilot will do the actions identified, and evaluate them. Is the engine responding? Is the aircraft moving? Etc. Of course then the cycle continues now because the pilot will detect that the aircraft is moving, so on and so forth. The detection of the takeoff clearance led to the decision to apply power and take off. This simplified illustration does not take in to consideration the factors that affect decision making discussed above like those of mental attitude (discussed below) on the takeoff decision, but it serves a basic example of the process.
The “mental process” of decision making is hard to fully quantify because metal processes differ among people. Because of the self-evident variable nature of human personalities, it is my opinion that it is impossible to list all of the psychological factors that affect decision making, but there are some common ones available to discuss. The FAA (1991) has paid respect to the function of attitude and the bias it can have on good decision making. They have identified five hazardous attitudes that can lead to poor decisions that may or may not be present in every person: “anti-authority, impulsivity, invulnerability, macho, and resignation” (FAA, 1991). Other factors that affect decision making include inaccurate situational awareness (Jones, 2006), flying experience (Morrow & Shriver, 2008), training in aeronautical decision making (Harris & Li, 2008), and the experiences of other pilots as relayed through reflective study (Adele et al., 2010).
It is my opinion that decision making is an integral component of situational awareness. Both of the models of situational awareness reviewed above included decision making as a central component, and the decision making mnemonic included an element of detection or perception. Perception of course is the beginning of situational awareness. It really is a sort of chicken/egg kind of philosophical concept. You can’t have situational awareness without decision making and vice versa. Jones (2006) puts the matter succinctly: “although not synonymous, decision-making and situational awareness are inextricably linked.”
Figure 3 has been provided from the FAA 60-22 advisory circular on aeronautical decision making. On examination of the diagram, the central factor identified is “situation”. That of course illustrates the importance of situational awareness in decision making.
- Figure 3. Aeronautical decision making process illustrated.
In order to illustrate the integration of situational awareness and decision making consider the following example:
A private, instrument rated pilot in a single engine aircraft is waiting at the hold short line of runway 25, the current goal is to take off. The pilot perceives the following information, building his/her picture of level 1 situational awareness: The engine is running and operating within normal parameters, the aircraft is stopped at the hold short line. The wind is 260 at 5 knots, the runway is dry, it is daylight outside, the transponder is set correctly, the lights and radios are on and set correctly and the tower has cleared the pilot to take off.
The pilot reviews the level 1 information, adding his/her mental model of the aircraft systems and his/her goal of taking off to the data and achieves the level 2 situational awareness that he/she is ready and also cleared to take off.
Understanding that he/she is ready and cleared for takeoff, and that when he/she applies power the aircraft will move onto the runway, accelerate, generate lift and fly away with the proper control inputs the pilot has attained level 3 situational awareness.
The pilot having detected the radio call from the tower clearing him for takeoff, estimates that he/she will need to respond to the tower, chooses the option of making the radio transmission acknowledging the clearance to take off, identifying that he/she must key the microphone, does key the microphone to transmit, and evaluates, in this case by listening for any further transmissions from the radio.
The pilot having responded to the tower and having detected the clearance to take off estimates that he/she will need to move on to the runway and take off without undue delay, he/she chooses the option of applying power and lining up for takeoff, identifying that he/she must move the throttle control, and maneuver the airplane with rudder and brakes, does so, and evaluates the response of the engine, and the aircraft toward the desired goal of taking off.
The situational awareness cycle simultaneously begins again with the perception of the motion of the aircraft (level 1). The pilot understands that the aircraft is moving along the runway (level 2), and that he/she will soon rotate for takeoff (level 3) as is his/her goal to do so. Data driven processing plays a part as he/she evaluates the motion of the aircraft, and instrument panel indications. Those indications may initiate a decision process that could lead to continuing the takeoff (current goal) or aborting it (possible new goal).
Throughout the dynamic process of situational awareness and decision making, the pilot perceives information that will influence both of the processes of situational awareness and decision making. That data will pass through perception process to short term memory, be processed by the long term memory, components of mental models, schemata and experience and arrive at an action performed by the pilot (Endsley, 1995). This treatment of situational awareness and decision making is basic. A gifted researcher could potentially write a book on each topic presented, but purpose of this post was to simply illustrate them.
Situational awareness is about building an accurate mental picture of the environment. Decision making is about choosing how to interact with that environment. As noted above they are fully integrated cognitive processes, susceptible to errors like mental attitude and misperception, yet responsive to experience and training.
As usual, the in-text references are available upon request. Please let me know if you have questions.