Human Factors Flashcards
(38 cards)
Hypoxia
Lack of oxygen
Hypoxic hypoxia
Insufficient oxygen available to the body as a whole - ex sublimation of dry ice.
Hypemic hypoxia
Oxygen deficiency in the blood. Mostly due to CO poisoning and anemia
Stagnant hypoxia
Oxygen rich blood in lungs not flowing. Ex arm going to sleep. Occurs with excessive acceleration of gravity G’s
Histotoxic hypoxia
Inability of cells to effectively use oxygen. Toxic. Alcohol or drugs. One oz of alcohol equates to 2000’ of physiological altitude.
Symptoms of hypoxia
From high altitude. Euphoria or carefree feeling.
- cyanosis (blue fingernails/lips)
- headache
- increased reaction time
- impaired judgement
- visual impairment
- drowsiness/lightheaded
- tingling/numbness
Hypoxia treatment
Flying lower or supplemental oxygen
What is hyperventilation
Excessive respiration leading to loss of carbon dioxide from the blood.
Hyperventilation symptoms
- Visual impairment
- unconsciousness
- lightheaded
- tingling sensation
- hot and cold sensation.
- muscle spasm
Hyperventilation treatment
Slow breathing, breath into paper bag or talking aloud.
Middle ear/sinus problems and remedy
Pressure differences between middle ear and outside world not equalized.
Pinch nostrils and blow slowly
When does sinus block occur
Descent. Use slow descent rates. Don’t fly with upper respiratory infections or nasal allergic conditions.
Spatial disorientation
Lack of orientation with regard to the position, attitude or movement of the aircraft in space due to conflicting agreement of the vestibular, somatosensory, and visual systems.
Those did vestibular illusions
The leans - sudden return to level flight after gradual and prolonged turn feels like banking to the opposite.
- Coriolis illusion: turning long enough for fluid in ear canal to move same speed as canal then a turn in head creates illusion aircraft turning or accelerating.
- graveyard spiral: prolonged constant-rate turn illusion of not turning. Actions put aircraft into a spiral
- somatogravic illusion: rapid acceleration causes belief in nose up attitude.
- inversion illusion: abrupt change from climb to straight and level creates illusion of tumbling backward.
- elevator illusion: abrupt vertical like in an updraft creates illusion of being in a climb.
Visual illusions
- false horizon: sloping clouds or obscured origin
- autokinesis: stationary light may appear to move.
Motion sickness and response
Brain receives conflicting messages about the body. Anxiety and stress can contribute.
Open fresh air vents, focus on object outside, and avoid sudden head movements.
Carbon monoxide poisoning
CO is odorless gas produced by all engines. Prevents hemoglobin from carrying oxygen to cells resulting in hypemic hypoxia.
Turn off heater and open fresh air vents.
Smoking at sea level can raise the CO concentration in the blood and result in physiological effects similar to flying at 8000’
Stress
Bodies response to the physical and psychological demands placed on it. Body releases chemical hormones into blood increasing the metabolism. Blood sugar, heart rate, blood pressure, respiration and perspiration all increase.
Two tours of stress
Acute and chronic
Acute stress
Short term involving an immediate threat perceived as a danger
Chronic stress
Level of stress that presents an intolerable burden. Unrelenting psychological pressures. Unfit to fly.
Fatigue.
Frequently associated with Pilot error. Degradation of attention, concentration, impaired coordination and ability to communicate.
Acute fatigue.
Normal tiredness. Causes timing disruption and disruption of perceptual fields. Results in mild hypoxia, physical and psychological stress.
Proper diet and sleep
Chronic fatigue.
Continuous high stress levels. Consult a physician.
