Human Factors and Aviation Safety Lecture Notes

Comprehensive practice flashcards covering Human Factors, cognitive biases, memory models, safety cultures, error classification, and ATC operational dynamics.

What are the 5 primary cognitive biases?

Frequency, Association, Confirmation, Expectation, and Group conformity.

In cognitive bias, how is "Frequency" defined?

Over- or underestimating risk based on personal experience.

In cognitive bias, how is "Confirmation" defined?

Looking for evidence that supports our decisions while ignoring conflicting evidence.

What is the definition of Human Factors?

Human factors is the application of a range of human sciences, related to the understanding of why people make mistakes and in particular, how human performance limitations contribute to accidents.

What is the Reason Model and what are its 5 layers?

A model that describes a chain of events that leads someone to commit an incident (the "Swiss cheese" model where an incident occurs when the holes line up). Its 5 layers are decision-makers, line management, preconditions, productive activities, and defences.

What are the symptoms of hypoxia listed under the "FADING" mnemonic?

Fixation (mental), Adversely affected judgement, Dimmed vision or visual changes, Impaired/sluggish thinking, Nail/lip cyanosis, and Giddy / euphoric feeling.

What are the 3 levels of Situational Awareness (SA)?

1. Perception (noticing information), 2. Comprehension (understanding the situation), and 3. Projection (predicting future events).

What factors can cause Situational Awareness (SA) to be lost?

High workload, distraction, insufficient information, over-reliance on automation, low motivation, and non-standard procedures.

How can Situational Awareness (SA) be regained?

By re-scanning the traffic picture, verifying information, training, communication, or removing factors causing SA loss.

What are the 3 error classifications described in human performance?

Skill based (slips and lapses), Rule based (misapplication of a good rule or application of a bad rule), and Knowledge based (inadequate or inappropriately applied knowledge).

In skill-based errors, what is the distinction between slips and lapses?

Slips are physical errors or losses of focus during task execution, whereas lapses are memory lapses or forgetting.

What are the four factors associated with knowledge-based errors?

Selectivity (attention to wrong info), Confirmation Bias (searching for info to support/confirm decision), Availability Bias (comes to mind faster, valued higher), and Entrapment (sticking with a plan).

What are the two main types of long-term memory and how are they exemplified in ATC?

Declarative memory involves knowing facts and information (e.g., separation standards), and Procedural memory involves knowing how to perform tasks (e.g., applying separation standards through experience).

What are the 3 main memory types and their key characteristics?

Sensory memory (Iconic, Echoic), Short-term memory (Phonological Loop, Visual Spatial Scratchpad; capacity of $7 \ne 2$ items, expandable by chunking), and Long-term memory (Declarative and Procedural; limitless capacity).

What are the main components and capacity of short-term / working memory?

Components include the Central executive (controls attention & information flow), Visuospatial scratchpad (processes visual and spatial info), and Phonological loop (processes verbal and auditory info). Capacity is $7 \ne 2$ unrelated items.

How do the "Conservative Style" and "Surfer Style" decision-making styles differ?

Conservative Style is basic and safe with more constant attention. Surfer Style is fun, highly efficient, sometimes risky, and marked by attention highs and lows.

What is the "Bystander effect" and what is an example of it in ATC?

The concept that the more people present, the less individual responsibility is felt due to diffusion of responsibility. In ATC, each controller assumes the other will act, so nobody does.

What is "Group Think" and how does it manifest in ATC?

People agreeing with the group to avoid conflict or rejection, making group agreement more important than making the safest decision. In ATC, controllers stay silent about concerns to avoid disagreeing with colleagues.

What is "Group Polarisation" and how does it relate to ATC?

When group decisions become more extreme (either riskier or more cautious) because a shared decision makes individuals feel less accountable. In ATC, controllers agree to a riskier or overly cautious decision than they would individually.

What is "Obedience to Authority" and what rule should ATC controllers follow regarding it?

The tendency for people to follow instructions from authority figures even when they believe they are wrong (e.g., following a manager's decision despite recognizing it is unsafe). Controllers must always speak up about safety concerns, regardless of rank.

What is "Social Loafing" and how can it be mitigated in ATC?

People putting in less effort when working in a group (e.g., assuming others will handle tasks). It is mitigated by making individual responsibilities clear and contributions identifiable.

What are the 3 types of communication and their ATC best practices?

Verbal (spoken words; use standard ATC phraseology and clear tone), Non-verbal (body language, posture, and tone; ensure signals do not send unintended messages), and Written (paper or digital; keep messages clear and unambiguous).

What are the main barriers to communication?

Gender, emotional state, age, personality, world view, and culture.

What is the TEM (Threat and Error Management) Model?

A safety framework for understanding and managing threats and errors in operations before they lead to unsafe situations, acting as another layer of defence alongside the Reason model to prevent incidents and accidents.

What are the 4 states under the TEM model?

Threats (external events to be managed), Errors (controller actions/inactions deviating from intentions), Undesired States (unsafe traffic situations reducing safety margins), and Outcomes (final results like incidents or accidents).

What are the three types of errors categorized under the TEM model?

Spontaneous, linked to threats, or part of an error chain.

What is the purpose of standard procedures and what makes them effective?

Purpose: to help humans work safely and consistently as technology advances. Effective procedures are documented, regularly reviewed and updated, simple, unambiguous, and clearly understood.

What is the difference between tactical and strategic decisions in ATC?

Tactical decisions are immediate decisions to control aircraft and manage current traffic situations, whereas strategic decisions are longer-term planning decisions (e.g., traffic flow management, handovers, overall sector planning).

What are the pros and cons of a "No-Blame" culture?

Pros: encourages honest reporting and helps organisations learn from errors. Cons: reckless or repeated unsafe behaviour goes unpunished, reduces personal responsibility, and does not distinguish culpability for unsafe acts.

What is a "Just" culture and what is its primary difficulty?

A culture where people are encouraged to report errors without fear of unfair punishment but are held responsible for reckless or deliberate unsafe behaviour. The primary con/difficulty is deciding whether an action was an honest mistake or unacceptable behaviour.

What are the characteristics of a safe culture?

Mindfulness of danger, accepts setbacks, committed, reviews events to collect data and improve defence, recognises institutional factors, prioritises safety over money, and encourages reporting by not blaming honest mistakes.

What are the advantages and disadvantages of habit and routine?

Advantages: well-practised routines reduce effort and help prevent boredom-related errors. Disadvantages: can cause errors when situations change, delay recognition of unusual events, reduce forward planning, and make experienced people more prone to deeply ingrained habit-based errors.

What factors influence decision making according to the notes?

How information is presented, reliability and clarity of information, use of negative evidence, and biases in thinking.

What is physical ergonomics and why is it important?

It is concerned with the physical fit between humans and their equipment. It is important because intuitive systems lead to fewer errors, and systems meeting expectations improve safety.

What are the 4 steps of the information processing model?

1. Sensation, 2. Perception, 3. Planning, and 4. Execution.

What does the SHELL model stand for and what is its role according to ICAO?

Software (procedures), Hardware (machines and equipment), Environment (internal and external workplace), and Liveware (people). It is used by ICAO to differentiate between basic sub-systems of aviation and identify how their interaction is influenced by human capability.

What are the four key areas for managing fatigue?

Sleep (adequate sleep in a $24\text{ hr}$ period, manage sleep debt, cool/dark/quiet room), Exercise (regular exercise for physical health and sleep quality), Nutrition (light meals on night shifts, avoid caffeine/alcohol close to bedtime), and Workplace measures (fatigue management procedures, maximum duty hours, minimum rest periods, safe rostering).

What is the difference between Eustress and Distress on the stress curve?

Eustress (optimum stress) is a comfortable, welcome amount of stress that allows adaptation and enhances performance. Distress results from underload or overload/burn-out, where demand cannot be handled, resulting in debilitating effects and decreased performance.

What strategies are recommended to manage high workload?

Prioritize tasks, filter information according to priority, use chunking, reminders and cues, avoid competing tasks that use the same perceptual system, and recognize signs of overload early.

How is information lost from short-term / working memory?

Information is lost after $10\text{--}20\text{ seconds}$, through interference (new or similar info replaces or confuses existing info), or through acoustic confusion (similar-sounding items mixed up).

How does high workload affect memory?

It overloads limited working-memory capacity, causing information to be lost, confused, or transposed, while attention and performance deteriorate.

What are the limitations of visual and auditory perception?

Visually, we see what we expect to see, what experience allows us to see, and what physiology allows us to see. Auditorily, we hear what we need to hear, expect to hear, and what experience, physiology, and environment allow us to hear.