Human Factors Flashcards
What is the atmosphere made up of?
78% nitrogen, 21% oxygen, 1% trace gases
What is barotrauma?
Gases trapped in our bodies expanding due to the decrease in pressure with altitude. These trapped gases can cause pain.
What is decompression sickness?
Excess nitrogen in the blood bubbling out into the muscles and joints; this is called the bends.
After scuba diving how long should you not fly for?
4 hours after diving if no decompression stops were needed.
12 hours if the session was LESS than four hours with decompression stops.
48 hours if the session was MORE than four hours duration with decompression stops.
How long would you need to wait before flying if you were diving with no decompression stops?
4 hours
If you were diving for 3 hours and required decompression stops how long would you have to wait to fly?
12 hours. As the diving session was less than four hours and you required decompression stops.
If you were diving for 5 hours and required decompression stops how long would you have to wait before flying?
48 hours as the diving session was more than four hours and required decompression stops.
How deep do you dive to require decompression stops?
10m (33ft)
What is hyperventilation?
Over breathing resulting in the alteration of the body’s acid balance.
What is hypoxia?
Insufficient oxygen available for the body to function. At high altitudes, this is due to insufficient partial pressure of oxygen.
What are the symptoms of hypoxia?
Blue discoloration of the fingernails and lips, warmth, wellbeing, overconfidence, giddiness, light headedness, failure of vision, eventual loss of consciousness.
What does a blue discoloration of the fingernails and lips indicate?
Hypoxia; blue discoloration is cyanosis.
What is the difference between Hypoxia and Hyperventilation?
Cyanosis; blue discoloration.
What is a blackout and what is the threshold for this?
A blackout is caused by pulling positive Gs at an average of 4.7G; the range is 2.7 to 7.8G.
What are the different types of stress?
Physical, physiological, emotional.
What is Acute fatigue?
Occurs due to physical or mental exhaustion, usually cured by a good night’s sleep or a couple of days rest.
What is Chronic Fatigue and why is it a problem?
Fatigue that has built up over weeks, months, or even years. Can be caused by difficult rosters, work or social pressures, or problems at home. The only cure is attending to the underlying issues.
What are threats, and what are the 2 types of threats?
Any situation or event that has the potential to impact negatively on flight safety; it promotes the opportunity for pilot error. The two types are internal and external.
What are internal threats?
Threats brought on by the crew: pilot fatigue, language/cultural barriers, pilot experience and personality, teamwork, health and fitness.
What are external threats and what are the three types?
Threats from the outside environment. Expected: weather, traffic, unfamiliar aerodromes. Unexpected: distractions from passengers, in-flight diversions, and missed approaches. Latent (hidden): poor cockpit design, company policy.
What are expected threats?
An expected threat is a type of external threat, e.g., adverse weather, heavy traffic, unfamiliar aerodromes.
What are unexpected threats?
Unexpected threats include distractions from passengers, in-flight diversions, and missed approaches.
What is an Error and what kind of errors are there?
An error originates from a pilot’s actions or inactions that have the potential to adversely affect the safety of the flight. There are aircraft and handling errors, procedural errors, and communication errors.
What is a mishandled error defined as?
One that leads to a further error or an undesired aircraft state.
What is a procedural error?
Not following procedures, not using checklists, flying incorrect circuit directions.
What are the three types of handling errors?
Systematic, Random, Spiritic.
What is a systematic error?
Errors that occur with a definite pattern.
What is a random error?
An error that occurs without any specific pattern.
What is a Spiritic Error?
The most difficult error to fix; an error that occurs very rarely in one element which has otherwise been performed correctly.
Most common cause of pilot incapacitation?
Food poisoning
How long after blood donations should you not fly?
24 hours
What is the blood alcohol allowed to fly?
0.02
How long between after drinking can you fly?
8 hours bottle to throttle
How does alcohol leave the body?
Urinating, breathing and metabolic processes
What are some types of medications that you should use while flying?
Analgesics, Laxatives, common cold medication, indigestion remedies, stimulants, antibiotics, sedatives, blood pressure medication.
What does the IMSAFE check list stand for?
Illness, Medications, Stress, Alcohol, Fatigue, Eating
What class of medical do you need for your private pilot license?
Class 2 or 3 medical
Incapacitation/unwell for how long before it needs to be reported to your DAME?
30 days PPL class 2 or 3, 7 days for CPL class 1
What are the functions of the ear?
Hearing and balance
What does the eardrum do?
The eardrum vibrates to sound waves arriving through the canal
What are the Ossicles, what else are they known as and what are their function?
The ossicles are 3 bones in the middle ear aka the hammer, anvil and stirrup; they transfer vibrations from the eardrum to the inner ear.
What is the Eustachian tube and what is its functions?
The middle ear is vented to the atmosphere via the Eustachian tube. The Eustachian tube connects the middle ear to the throat cavity and allows pressure either side of the eardrum to be equalized.
What is barotrauma and what is it caused by?
Pain caused by an imbalance of pressure on either side of the eardrum due to a blocked Eustachian tube.
What is the Cochlea and what does it do?
The Cochlea converts sound vibrations into electrical impulses which are sent to the brain to interpret as sound.
What is located in the inner ear responsible for changing sound vibrations into electrical impulses?
The Cochlea
Where is the cochlea located and what does it look like?
The inner ear, looks like a snail
What are the semicircular canals? What do they do?
Located in the inner ear, they are responsible for sensing angular acceleration (pitch, yaw and roll) and mediating sense of balance.
Where is the Otolith organ and what is it responsible for?
In the inner ear connected to the semicircular canals, the Otolith organ is responsible for sensing linear acceleration (straight line acceleration/deceleration).
What is the db of a light aircraft cockpit?
80db-100db
What are the 3 primary systems involved in maintaining body equilibrium?
The visual system, the vestibular system – inner ear balance, and the proprioceptive system – nerves.
What db is it recommended to wear hearing protection?
Above 85db
What does the retina do?
Converts light rays into electrical impulses to send to the brain via the optic nerve so we can see.
What are the photo sensitive cells that detect colour and fine detail called?
Cones
What are cones?
Photo sensitive cells that detect colour, small details and distant objects. Most effective in daylight.
What are the photo sensitive cells that are sensitive to movement?
Rods, responsible for peripheral vision and night vision.
What are rods, and what are they responsible for?
Rods are photo sensitive cells located on the retina above and below the cones; they give us our night vision and peripheral vision.
What is empty field Myopia and how do we prevent this?
Tendency for the eye to rest while there is nothing to focus on, usually occurs 1-2 meters in front of you. A way to avoid this is by looking at the wingtip from time to time to refocus.
What is the first sense affected by hypoxia?
Vision, often color vision.
What is Anaemic Hypoxia?
The reduced ability of the blood to carry oxygen. Most common cause is carbon monoxide poisoning. Haemoglobin bonds with carbon monoxide easier than it does with oxygen.
What is the Time of useful consciousness?
The time which you can act with physical efficiency and alertness from when an adequate oxygen supply is no longer available. 20,000ft less than 10 mins, 30,000ft less than 1 minute.
What is Hyperventilation?
Excessive breathing leading to abnormal loss of carbon dioxide from the blood.
When is barotrauma most likely to occur?
Barotrauma is most likely to occur during rapid descent.
What is somatogravic illusion?
The tendency, in the absence of visual reference to incorrectly perceive acceleration as an increase in pitch attitude.
What is the Coriolis illusion?
Sudden or intense feeling of tumbling, often accompanied by nausea. It occurs when a pilot has been in a turn long enough for the fluid in the inner ear’s semicircular canals to stabilize and move at the same speed as the canal.
What is the Autokinetic illusion?
Occurs at night when pilots stare at a fixed point of light against a dark background. Light may appear to move and the pilot may make unnecessary inputs.
What can hazy conditions cause?
Things to appear further away than they are.
What is a Greyout?
Partial loss of vision caused by hypoxia during sustained G’s. Vision obscured by a grey haze. Remains fully conscious occurs around a min of 3.5g.
What is a Blackout?
At around 5 g’s pilots’ entire vision field turns black, can’t see but remains conscious.
What is G-LOC?
Gravity induced loss of consciousness.
