Human Performance & Limitations
Human factors, physiology, and psychological aspects affecting pilot performance.
Overview
Human Performance and Limitations examines how the human body and mind function in the aviation environment. Understanding physiological limitations (hypoxia, spatial disorientation), psychological factors (stress, workload management), and decision-making frameworks helps pilots maintain safety margins and avoid human factor-related accidents.
Key Topics
1. Hypoxia
Oxygen deficiency affecting brain function. Symptoms include euphoria, impaired judgment, cyanosis, and loss of consciousness. Types include hypoxic (altitude), anemic (carbon monoxide), stagnant (G-forces), and histotoxic (alcohol). Supplemental oxygen required above 10,000 feet.
2. Vision in Aviation
The eye adapts slowly to darkness (30+ minutes for full dark adaptation). Night vision limitations, blind spots, empty field myopia, and scanning techniques. Understanding how lighting conditions affect visual perception during flight.
3. Spatial Disorientation
Conflicts between visual and vestibular (inner ear) senses. The leans, somatogravic illusion, Coriolis effect, and graveyard spiral. Always trust instruments over physical sensations in IMC conditions.
4. Stress and Fatigue
Acute vs. chronic stress, fatigue types (acute, chronic, skill-based), circadian rhythm disruption, and the effects on performance. The IMSAFE checklist (Illness, Medication, Stress, Alcohol, Fatigue, Emotion) for self-assessment.
5. Decision Making (ADM)
Aeronautical Decision Making models: DECIDE (Detect, Estimate, Choose, Identify, Do, Evaluate), hazardous attitudes (anti-authority, impulsivity, invulnerability, macho, resignation), and Crew Resource Management (CRM) principles.
6. Effects of Alcohol and Drugs
Alcohol impairs judgment and coordination even below legal limits. The 8-hour "bottle to throttle" rule (some authorities require 12+ hours). Medications may have side effects that are incompatible with flying.
Key Terms & Definitions
Exam Tips
- Tip 1:Memorize the IMSAFE checklist and its applications
- Tip 2:Know the five hazardous attitudes and their antidotes
- Tip 3:Understand hypoxia symptoms and the altitude thresholds for supplemental oxygen
- Tip 4:Learn the time of useful consciousness at various altitudes
- Tip 5:Remember: when in doubt about spatial disorientation, always trust instruments
Recommended References
Pilot's Handbook of Aeronautical Knowledge Ch. 2
FAA handbook covering aeromedical factors
Human Performance and Limitations (EASA)
European study material for HPL examination
FAA Advisory Circular 60-22
Aeronautical Decision Making guidelines
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