Human Factors: Basic Concepts and General Aviation Psychology
What the domain tests
Human Factors (HF) at ATPL level asks you to explain how people, procedures and machines interact, and to apply models rather than recite definitions. The exam favours the ICAO SHELL model, Reason's model and general-aviation psychology such as hazardous attitudes and decision traps.
Core rules
- SHELL places Liveware at the centre; the edges are Liveware–Software (procedures, checklists), Liveware–Hardware (controls, displays), Liveware–Environment (weather, noise, light) and Liveware–Liveware (crew, ATC, passengers). A mismatch at any edge creates error.
- Reason's Swiss-cheese model separates active failures at the sharp end from latent conditions in supervision and organisation; defences align only occasionally.
- HF is systems-focused. Blaming the last person to touch the aircraft is not an HF explanation.
- FAA hazardous attitudes: anti-authority, impulsivity, invulnerability, macho, resignation, each with an antidote such as 'follow the rules' or 'it could happen to me'.
- Motivation, personality, risk perception and flight discipline shape decisions as much as handling skill.
Worked example
A private pilot continues VFR into deteriorating visibility. SHELL shows a Liveware–Environment mismatch between visual capability and weather, a Liveware–Software gap (no written personal minimums) and Liveware–Liveware pressure from a passenger. Reason's model places the active failure on latent conditions. The attitude is invulnerability; the antidote is 'it could happen to me'.
Traps
Do not describe SHELL as an error chain; the edges are interfaces. Do not call a violation an error. Do not stop at 'pilot error' - give the precondition and organisational levels. Do not confuse hazardous attitudes with personality types.