EASA Module 8 flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Murphy's Law

The principle that if anything can go wrong, it will; used in aviation to justify checklists, independent inspections and defensive design.

SHEL model

A human factors framework comprising Software, Hardware, Environment and Liveware, focusing on the interfaces between people and other system components.

Human factors definition

The study of human capabilities, limitations and behaviour, and how these interact with the aviation system to affect safety and performance.

Dirty dozen

Twelve common maintenance error precursors including fatigue, complacency, distraction, pressure, stress, lack of communication, teamwork, knowledge, resources, awareness, assertiveness and norms.

Dark adaptation time

The process by which the eyes adjust to low light, taking about 30 minutes; bright light resets it and forces readaptation.

Fovea centralis function

The central retinal region with the highest cone density, providing sharp colour vision used for detailed inspection and reading.

Short-term memory capacity

Approximately 7 ± 2 items retained for about 15–30 seconds without rehearsal, limiting how much information a person can hold at once.

Noise-induced hearing loss

Permanent hearing damage from prolonged exposure to loud noise, typically first appearing as a notch at about 4 kHz.

Presbyopia

Age-related loss of the eye's ability to accommodate, reducing near vision and typically beginning around 40 years of age.

Peer pressure

Social influence from colleagues that can push an individual to adopt group norms or unsafe practices against their own judgement.

Groupthink

A mode of thinking in cohesive groups where the desire for harmony suppresses dissent and realistic evaluation of alternatives.

Just culture

A safety culture that distinguishes human error from at-risk and reckless behaviour, encouraging reporting without fear of blame.

Authority gradient

The perceived difference in power or expertise between team members; a steep gradient discourages juniors from speaking up.

Yerkes-Dodson law

Performance improves with arousal up to a moderate optimum, then declines; too little or too much stress impairs performance.

Fatigue equivalent to alcohol

Being awake for about 17 hours impairs performance similarly to a blood alcohol concentration of 0.05%, and 24 hours to 0.10%.

Circadian low points

Daily dips in alertness around 03:00–05:00 and 15:00–17:00, when error risk from fatigue is highest.

Alcohol elimination rate

Blood alcohol concentration falls by approximately 0.015% per hour; only time removes alcohol, and hangover effects persist.

Noise exposure limit

An 8-hour exposure above 85 dB(A) generally requires hearing protection; 90 dB(A) is a common occupational limit.

Task illumination level

About 500–1000 lux is used for detailed inspection, while general work areas typically need 300–500 lux.

Whole-body vibration range

Frequencies of roughly 0.5–80 Hz affect the whole body, while hand–arm vibration spans about 8–1000 Hz.

Vigilance decrement

The decline in detection performance during prolonged monitoring, becoming noticeable after about 20–30 minutes of monotonous watch.

Automation complacency

Over-reliance on automated systems that reduces monitoring and manual skill, so operators may miss failures or unexpected states.

Repetitive task risk

Repeated movements without adequate recovery can cause musculoskeletal disorders; task rotation and micro-breaks reduce the risk.

Visual inspection reliability

Inspection is imperfect and detection rates vary; independent second checks and good lighting improve the probability of finding defects.

Read-back communication

A closed-loop technique where the receiver repeats an instruction so the sender can confirm it was understood correctly.

Shift handover

The transfer of task status and responsibility between shifts, ideally structured and allowing questions to confirm understanding.

Technical log requirements

Entries should be legible, permanent, contemporaneous, accurate and signed, forming the legal record of maintenance work.

Swiss cheese model

Reason's model in which accidents occur when holes in multiple defensive layers line up, allowing a hazard to pass through.

Slip versus mistake

A slip is a skill-based execution error, whereas a mistake is a rule-based or knowledge-based error in intention or planning.

Active and latent errors

Active errors have immediate effects at the point of work, while latent errors lie dormant in management or design decisions.

Hazard versus risk

A hazard is a potential source of harm; risk combines the likelihood and severity of that harm occurring.

Hierarchy of control

Measures ranked from elimination, substitution and engineering controls through administrative controls, with personal protective equipment as the last resort.