Human Performance and Limitations: Perception, Stress and Decision Making
What you must know
Human performance questions cover the senses used in flight, hypoxia, hyperventilation, spatial disorientation, stress, fatigue, workload, communication and decision making. Understand the physiology: the eye's rods (night, peripheral, motion detection) and cones (day, colour, central acuity), the blind spot, and the importance of off-centre viewing at night. Know the ear's role in balance, the somatogravic and somatogyral illusions, and why the instruments must be trusted over sensations in cloud. Recognise hypoxia symptoms, the time of useful consciousness at altitude, and the effect of smoking, alcohol and carbon monoxide. Understand stress as a performance curve and the difference between acute and chronic fatigue.
Traps in questions
- Believing the eyes give reliable attitude information in cloud - they do not; rely on instruments.
- Confusing hyperventilation (too much breathing, dizziness, tingling) with hypoxia (too little oxygen).
- Assuming alcohol effects wear off with coffee or fresh air; only time removes alcohol.
- Forgetting that night vision dark adaptation takes about 30 minutes and is destroyed by bright light.
Worked rule of thumb
Use the "one in sixty" scan discipline: at night, look 10–15° off-centre to place the image on the rods, and scan in short, regular movements rather than staring.
Study approach
Build a symptom table for hypoxia, hyperventilation and CO poisoning, and a separate list of illusions with the corrective action for each.