1 Background
This briefing note presents a definition of situational awareness. It explains the complex process of maintaining situational awareness, focuses on how it is lost and proposes prevention and recovery strategies.
This briefing note is intended to help the reader gain and maintain situational awareness, to prevent falling into the traps associated with its loss and to avoid the negative effects of its loss on flight safety.
2 Introduction
A widely accepted definition of individual situational awareness comes from Endsley (1988) :
The Aircrew Incident Reporting Scheme (AIRS) model in Figure 1
illustrates the most common factors that determine a pilot’s situational
awareness. As developed by Airbus and British Airways, AIRS contains
various personal, informational, environmental and organizational
influences that affect crew actions and, in turn, can be affected by how
the crew performs.
Figure 1: Elements of Situational Awareness
The main components of situational awareness are:
3 Data
Situational awareness is not just a theoretical notion. It is pertinent to most accidents or incidents, it is real, and its absence causes accidents. Research from The Australian Transportation Safety Board (ATSB) indicates that human factors are a contributing cause in around 70 percent of all incidents and accidents. Approximately 85 percent of incident reports include a mention of loss of situational awareness. Degraded situational awareness can lead to inadequate decision making and mistakes. This is illustrated in Table 1, which identifies causal factors in approach and landing accidents identified in the Approach and Landing Accident Reduction (ALAR) Toolkit.
Table 1. Causal Factors in Approach and Landing Accidents
4 Issues and Factors Involved
Gaining and Maintaining Situational Awareness
Situational awareness is having an accurate understanding of what is happening around you and what is likely to happen in the near future. As shown in Figure 2, Endsley’s definition suggests that situational awareness includes three processes:
Figure 2: Gaining and Maintaining Situational Awareness
Figure 3: Understanding the Situation by Matching Mental Model and Real World
Situational Awareness and the Decision-Making Process
Situational awareness is strongly related to the decision-making process. Figure 4 shows a simple model of the tight coupling between situational awareness and decision making. Situational awareness must precede decision making because the operator has to perceive a situation in order to have a goal.
Figure 4: Situational Awareness and Decision Making
The Decision-Making Loop
Our actions are driven by goals. To help us act to achieve our goals, we use our mental models to anticipate the outcome of our action. This can be thought of as feedforward.
The more we anticipate accurately, the more efficient we become in our tasks, the more energy we save, and the more we can preserve resources for unexpected situations. Conversely, by comparing the results of our actions with set goals, we can modify our actions or, if necessary, our goals. This feedback is vital to the success of the process.
Feedback and anticipation help keep our mental picture of the world aligned with the real world.
5 Losing Situational Awareness and How to Deal With It
Many factors can cause a loss of situational awareness. Errors can occur at each level of the process previously described. Table 2 lists a series of factors related to loss of situational awareness, conditions contributing to these errors and guidelines to prevent them. Refer to the Situational Awareness Quick Reference and Reminder for a more exhaustive list of best practices, prevention strategies and lines of defense. Accident and incident reports provide a good basis for determining the relative effect of the various factors on situational awareness.
Table 2. Factors involved in Loss of Situational Awareness
6 Key Points
This briefing note presents a definition of situational awareness. It explains the complex process of maintaining situational awareness, focuses on how it is lost and proposes prevention and recovery strategies.
This briefing note is intended to help the reader gain and maintain situational awareness, to prevent falling into the traps associated with its loss and to avoid the negative effects of its loss on flight safety.
2 Introduction
A widely accepted definition of individual situational awareness comes from Endsley (1988) :
Situational awareness is
|
Figure 1: Elements of Situational Awareness
The main components of situational awareness are:
- Environmental awareness: Awareness of other aircraft, communications between air traffic control and other aircraft, weather and terrain.
- Mode awareness: Awareness of aircraft configuration and flight control system modes. The latter includes such aspects as speed, altitude, heading, in armed/acquire/hold modes and the state of flight management system (FMS) data input and flight-planning functions.
- Spatial orientation: Awareness of geographical position and aircraft attitude.
- System awareness: Awareness of the aircraft systems.
- Time horizon: Awareness of time with respect to when required procedures or events, such as time to initial approach turn, will occur.
3 Data
Situational awareness is not just a theoretical notion. It is pertinent to most accidents or incidents, it is real, and its absence causes accidents. Research from The Australian Transportation Safety Board (ATSB) indicates that human factors are a contributing cause in around 70 percent of all incidents and accidents. Approximately 85 percent of incident reports include a mention of loss of situational awareness. Degraded situational awareness can lead to inadequate decision making and mistakes. This is illustrated in Table 1, which identifies causal factors in approach and landing accidents identified in the Approach and Landing Accident Reduction (ALAR) Toolkit.
Table 1. Causal Factors in Approach and Landing Accidents
Factor | % of Events |
---|---|
Inadequate decision making | 74% |
Omission of action or inappropriate action | 72% |
Non-adherence to criteria for stabilized approach | 66% |
Inadequate crew coordination, cross-check and back-up | 63% |
Insufficient horizontal or vertical Situational Awareness | 52% |
Inadequate or insufficient understanding of prevailing conditions | 48% |
Slow or delayed action | 45% |
Flight handling difficulties | 45% |
Deliberate non-adherence to procedures | 40% |
Inadequate training | 37% |
Incorrect or incomplete pilot/controller communication | 33% |
Interaction with automation | 20% |
4 Issues and Factors Involved
Gaining and Maintaining Situational Awareness
Situational awareness is having an accurate understanding of what is happening around you and what is likely to happen in the near future. As shown in Figure 2, Endsley’s definition suggests that situational awareness includes three processes:
- The perception of what is happening (Level 1)
- The understanding of what has been perceived (Level 2)
- The use of what is understood to think ahead (Level 3)
Figure 2: Gaining and Maintaining Situational Awareness
- Level 1 — Perception: Scanning and Gathering Data
- Level 2 — Representation: Understanding and Creating Our Mental Model
Figure 3: Understanding the Situation by Matching Mental Model and Real World
- Level 3 — Projection: Thinking Ahead and Updating the Model
Situational Awareness and the Decision-Making Process
Situational awareness is strongly related to the decision-making process. Figure 4 shows a simple model of the tight coupling between situational awareness and decision making. Situational awareness must precede decision making because the operator has to perceive a situation in order to have a goal.
Figure 4: Situational Awareness and Decision Making
The Decision-Making Loop
Our actions are driven by goals. To help us act to achieve our goals, we use our mental models to anticipate the outcome of our action. This can be thought of as feedforward.
The more we anticipate accurately, the more efficient we become in our tasks, the more energy we save, and the more we can preserve resources for unexpected situations. Conversely, by comparing the results of our actions with set goals, we can modify our actions or, if necessary, our goals. This feedback is vital to the success of the process.
Feedback and anticipation help keep our mental picture of the world aligned with the real world.
- A major loss of situational awareness occurs when inappropriate mental representations are activated in spite of real world evidence. People then act “in the wrong scene,” and seek cues confirming their expectations, a behavior known as confirmation bias.
- It helps us develop a mental picture of the world around us and use that mental picture to anticipate the future, to feed-forward.
- Because of the close coupling of real-world feedback, mental anticipation and adaptation of actions, we adjust our mental picture and modify our actions, and sometimes our goals, in response to differences between what we expect to happen and what is really happening. That is why we often feel that we have lost control when what we expect to happen does not happen.
5 Losing Situational Awareness and How to Deal With It
Many factors can cause a loss of situational awareness. Errors can occur at each level of the process previously described. Table 2 lists a series of factors related to loss of situational awareness, conditions contributing to these errors and guidelines to prevent them. Refer to the Situational Awareness Quick Reference and Reminder for a more exhaustive list of best practices, prevention strategies and lines of defense. Accident and incident reports provide a good basis for determining the relative effect of the various factors on situational awareness.
Table 2. Factors involved in Loss of Situational Awareness
Factors | Prevention Guidelines |
---|---|
Level 1: Perception | |
|
|
Level 2 and 3: Understanding and Thinking ahead | |
|
|
6 Key Points
- Situational awareness is essential for flight safety, and its influence and impact are pervasive.
- Situational awareness is gained by using the senses to scan the environment and compare the results with mental models.
- Planning, communication and coordination for upcoming flight phases, goal setting and feedback are essential ingredients of situational awareness and decision making.
- Inattention, distraction and high workload threaten situational awareness.
- Three proven ways to prevent the loss of situational awareness are to:
- Implement proven best practices
- Adhere to ICAO recommendations
- Follow company standard operating procedures
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