Human Factors

Objective

To become familiar with and apply the knowledge related to aeromedical factors.

Motivation

Understand the risks and mitigations for aeromedical factors that can effect flight safety, as they may happen to you, another pilot, or your passengers.

Timing

45 minutes

Format

• Slides

Elements

• Hypoxia
  • Cause: Hypoxia is a state of oxygen deficiency in the body sufficient to impair functions of the brain and other organs
  • Symptoms: Cyanosis, headache, dizziness, euphoria, impaired vision, drowsiness
  • Corrective Actions
    • Use supplemental Oxygen
    • Fly lower
    • Address any pollution in the air
  • Time of useful consciousness
• Hyperventilation
  • Cause: Excessive rate and depth of respiration leading to abnormal loss of carbon dioxide
  • Symptoms: Rapid breathing, visual impairment, sweaty skin, dizziness
  • Corrective Actions
    • Breath slowly
    • Speak something slowly
    • Breathe into a bag
• Middle ear and sinus problems
  • Cause: Blockage of the Eustachian tube which equalizes pressure between both sides of your ear drum. Often happens with inflammation
  • Symptoms:
    • Ear pain and pressure
    • Muffled hearing
  • Corrective Actions
    • Valsalva method
    • Descend slowly
    • Decongestants for passengers
• Spatial disorientation
  • Cause: Disagreement or confusion between your sensory systems about the aircraft's position, attitude, or movement
  • Symptoms:
    • Confusion
    • Loss of airplane control
  • Corrective Actions
    • Trust flight instruments
    • Limit maneuvering
    • Limit rapid head movements
• Illusions that contribute to spatial disorientation
  • The "leans"
  • Coriolis illusion
  • Graveyard spiral
  • Somatogravic illusion
  • Inversion illusion
  • Elevator illusion
• Motion sickness
  • Cause: The brain receiving conflicting messages about the state of the body's position in space.
  • Symptoms:
    • Nausea
    • Dizziness
    • Paleness, sweaty, clammy skin
    • Vomiting
  • Corrective Actions
    • Fresh air
    • Focus on objects outside the airplane
    • Avoid unnecessary head movements
• Carbon monoxide poisoning
  • Cause: Hypemic hypoxia caused by the presence of CO in the air, which attaches to hemoglobin in the blood.
  • Symptoms:
    • Headache
    • Drowsiness
    • Blurred vision
    • Loss of muscle power
  • Corrective Actions
    • Close header vent
    • Land and ventilate the cabin
    • Open fresh air vents
• Stress
  • Cause: The body’s response to physical and psychological demands placed upon it. Stress can be chronic or acute.
  • Symptoms:
    • Agitation
    • Not thinking well
    • Fatigue
  • Corrective Actions
    • Correct underlying stressors, which may require medical treatment for chronic stress
• Fatigue
  • Cause: Acute fatigue is caused by lack of sleep. Chronic fatigue usually has medical underpinnings.
  • Symptoms:
    • Drowsiness
    • Errors in judgment, timing, computation
    • Loss of muscle control
  • Corrective Actions
    • Chronic fatigue: correct underlying issues, which may require medical attention
    • Acute fatigue: Rest
• Dehydration
  • Cause: Critical loss of water or electrolytes from the body
  • Symptoms:
    • Headache
    • Fatigue
    • Drowsiness
    • Cramps
  • Corrective Actions
    • Drink plenty of fluids and electrolytes
    • Drink before you become thirsty
• Hypothermia
  • Cause: Exposure to cold temperature for extended periods.
  • Symptoms:
    • Coldness
    • Shivering
    • Drowsiness
    • Loss of consciousness
  • Corrective Actions
    • Move to a warmer environment
    • Add clothing, blankets, or coats
    • Cover exposed areas
• Alcohol
  • Symptoms:
    • Symptoms similar to that of hypoxia
    • Impaired judgement, coordination, reaction time
  • Regulations
    • Alcohol, 14 CFR Part 91.17:
      • 8 hours "bottle to throttle"
      • 0.04% BAC limit
      • Cannot carry drunk passengers, except in an emergency
• Drugs
  • Corrective Actions
  • Regulations
    • 61.53 disallows a pilot from acting as PIC if:
      • They have any known medical condition that would make them ineligible for a medical
      • Are receiving treatment or taking medication that would make them ineligible for a medical
• Dissolved nitrogen in the bloodstream after SCUBA dives
  • Cause: Dissolved nitrogen in the blood being forced out of body
  • Corrective Actions
    • For flights below 8,0000' MSL:
      • At least 12 hours after diving that does not require controlled ascent (non-decompression stop diving)
      • At least 24 hours after diving that does require controlled ascent (decompression stop diving)
    • For flights above 8,000' MSL: At least 24 hours
• IMSAFE checklist
• Optical Landing illusions
  • False Horizon
  • Runway Width Illusion
  • Sloping Terrain
  • Featureless Terrain
  • Water Refraction
  • Haze
  • Fog

References

Pilot's Handbook of Aeronautical Knowledge pg. 17-1