Human Performance and Limitations: Perception, Physiology and Crew Resource Management
Sensory systems and spatial disorientation
Understand how the vestibular system works: the semicircular canals sense angular acceleration and can give false sensations after a sustained turn, while the otoliths sense linear acceleration and gravity. The somatogravic illusion (a strong acceleration feels like a climb) and the leans are classic examination topics. Vision matters too: night vision relies on rods and is best achieved by off-centre viewing, and empty-field myopia occurs over featureless terrain.
Physiology of flight
Know hypoxia: symptoms, the time of useful consciousness at various cabin altitudes, and that the first sign is often euphoria rather than a warning. Understand decompression sickness, the effects of trapped gas in the ears and sinuses, and the risks of hyperventilation, which can mimic hypoxia. Cabin pressure and the oxygen requirements for crew and passengers are frequently tested.
Human factors and CRM
Know the SHELL model, threat and error management, and the difference between an error, a violation and a slip. Situational awareness has three levels: perception, comprehension and projection. Fatigue, stress and circadian rhythm affect performance; know the difference between acute and chronic fatigue.
Traps
- Confusing hyperventilation with hypoxia - both cause dizziness and tingling.
- Assuming a pilot can reliably detect hypoxia without training.
- Mixing up the illusions: somatogravic (acceleration), somatogyral (spin), and the leans.
Rule of thumb
In any disorientation scenario, trust the instruments and cross-check. If a question asks for the first action after a suspected illusion, the answer is almost always to maintain or regain instrument reference rather than to follow the sensation.