Exam Revision Flashcards
What height is considered to be the Physiological Zone?
MSL - 10000feet
What height is considered to be physiologically deficient zone?
10000-50000 feet
What is considered to be the Space Equivalent Zone?
50000 feet and above
What is the break down of the atmosphere?
78% Nitrogen
21% Oxygen
1% other gases (ozone, CO2, methane etc)
Does the percentage of gases in atmosphere change?
No, pressure may change but percentage relationship stays the same
What height is pressure approximately half that of atmosphere?
18000 feet
What is hypoxia?
Lack of 02 to tissue sufficient to cause impairment of function
What are the four types of hypoxia?
Hypoxic hypoxia (due to low o2 levels) Anaemic Hypoxia (insufficient blood) Stagnant (lack of flow, g force) Histotoxic hypoxia (poison)
At 33000 feet on 100% oxygen, what is this equivalent to?
Sea level on air
At 40000 feet on 100% oxygen, what is this equivalent to?
10000 feet on air
What are some signs of hypoxia?
Tingling cyanosis Loss of judgement Loss short term memory Slower reaction times Mental 'Tunnel vision" Hot flushes, (cherry cheeks) Sense of euphoria Muscular in-coordination and tremors Loss of peripheral, colour and night vision
What factors will increase risk of hypoxia?
Rate of ascent Exercise/fitness (lack there of) Illness/cold Fatigue Drugs and alcohol (hangover) Smoking Stress/workload
How do you ‘recover’ from hypoxia?
O2 mask, 100% oxygen Descend below 10000 feet Breathe normal rate and depth Declare emergency Land ASAP
What is oxygen paradox?
Worsening of symptoms following re-introduction of O2 after period of exposure to hypoxia
What is you useful level of conciousness at FL180?
20-30 minutes
What is your useful level of conciousness at FL250?
3-5 mins
What is your useful level of conciusness at FL300?
1-2mins
What is your useful level of conciusness at FL350?
30-60 seconds
What is your useful level of conciusness at FL400?
15-30seconds
What is your useful level of conciusness at FL430?
9-12 seconds
What are some post hypoxic symptoms?
Fatigue
Headache
Lethargy
What are some causes of hyperventilation?
Hypoxia Vibration Pain Excessive G forces Anxiety/fear/stress Motion sickness Voluntary over breathing Environmental stressors (high temperatures)
What are some symptoms of hyperventilation?
Dizziness Lightheaded Sensory changes Tingling Apprehension Unconsciousness then recovery
What are some body cavities that contain gas?
Teeth Lungs Gastrointestinal tract Middle ear Sinuses Post op sites
Gas expansion in lungs can lead to what illnesses?
Pneumothorax
Air embolism (air bubbles)
Pnemomediastinum
What can lead to gas expansion in the lungs?
Pressure changes and holding your breath
When is pain in the ears likely to occur?
During descent
Where in the ear are you likely to feel affects of pressure change?
Middle ear (known as barotrauma)
Why do we feel pain in the ear?
Air cannot easily escape Eustachian tube to equalise pressure
What are the four sinuses
Ethmoidal
Sphenoidal
Frontal
Maxillary
What are some techniques to avoid trapped gas problems?
Valsava technique
Fly when healthy
Equalise ear pressure regularly when on descent
Eat non gaseous type foods/maintain healthy diet
What are the two types of pressure systems in aircraft?
Pressured and sealed cabins
What altitude is high differential systems normally set at?
About that of 5000-8000 feet
What are the advantages of high differential systems?
Minimal 02 consumption
No Decompression illness
Don’t need special equipment
What are the disadvantages of high differential systems?
Payload and endurance penalty
Large decompression on failure
If the high differential system fails, how can you prevent hypoxia from occurring?
Breath cabin air
Supplementary 02 available
What are the advantages of low differential systems?
Optimum payload and endurance
Minimum decompression on failure
What are the disadvantages of low differential systems?
Greater risk of hypoxia and DCI
Greater O2 requirement
What are some physiological effects of cabin depressurisation?
Pressure changes (ears, stomach, lungs sinuses) Hypoxia Decompression illness Cold (-56 degrees) Noise
What is spatial disorientation?
Inability to correctly interpert a/c, altitude or attitude or airspeed in relation to Earth or other points of reference
What are the three types of spatial disorientation?
Recognised
Unrecognised
Incapacitating
What is the make up of orientation?
Eyes 80%
Proprioceptors 10%
Vestibular 10%
What is the stimulation threshold of the semi circular canals?
2 degrees / second squared
What does the semi circular canals pick up?
Angular acceleration
How many semi circular canals do we have in each ear?
3
What do our otolith organs detect?
Linear acceleration and sense gravity
How many otolith organs do we have?
2 per ear
What are proprioceptors?
Sensitive to touch
‘Seat of pants’
What are some vestibular illusions?
Somatogravic
Somatogyral
Leans
Cyrolis
What is somatogravic illusion?
Dark night, acceleration, think you are pitching up.
Deceleration = pitch down
What is somatogyral illusion?
False sense of rotation
‘graveyard spin’
poor visual clues
What are the leans?
False sense of roll
cause pilot to lean to cancel sensation
What is coriolis illusion?
False sense of tumbling
May cause nausea and vomitting
What is autokinesis?
Illusion involving apparent moving of single point source of light.
Eyes normal movement are interpreted by the bran as movement of object
What is empty field myopia?
Eyes naturally rest at 1-2 m resulting in distance vision being reduced
How can you ‘cure’ empty field myopia?
Focus on something in distance (ie wingtip)
What a focal traps?
Object (Bugs/dirt/oil etc) on the windscreen leading to your eyes focusing on that object
How can you deal with visual illusions?
Being aware of them, signs, symptoms etc Prior planning Good visual scans Trust instruments Fly when healthy Limit head movement
What is the cornea and how much focusing % does it make up?
Majority of focusing ability of eye
75%
What is the lens and how much focusing % does it make up?
Fine tunes the visual image
25%
What is the retina?
Light sensitive area where light converted to electrical impulses
Where do the rods and cones ‘live’?
In the retina
What does the iris do?
Controls the amount of light entering the eye
What does the pupil do?
Operative in iris through which light enters the eye
What do the cones do and where are they concentrated?
High resolution and detail (colour, red green and blue)
Gives best visual acuity
Concentrated in fovea
What is each cone connected to?
Single optic nerve fibre
What are rods and where are they located?
Give poor visual acuity, resolution and detail.
Not sensitive to colour
Night vision
Located in peripheral retina outside fovea
What is the blind spot?
Where there is a lack of rods and cones at optic disc
What can blind spot do to an object?
Block an 18m object at 200m away
What degrees does blind spot affect?
2-6 degrees
On average, what is the total time to perceiver and react to oncoming traffic?
5 seconds
1 second to detect, 2 seconds to decide what to do 2.5 seconds for muscle movement
How long does it take for rods to adapt to the dark?
30-45 minutes
What are some techniques to assist with night blind spot?
Look off centre
Never fixate more than 2-3 s
15 degrees overlap
With night vision, what does it deteriorate at, at 4000 feet?
5% worse
With night vision, what does it deteriorate at, at 10000 feet?
20% worse
What is the OHS limit for noise exposure?
85db
If noise level is 88db, what is OHS exposure limit?
4 hours
If noise level is 82 db, what is OHS exposure limit?
16 hours
What are the primary signs and symptoms of motion sickness?
Pallor (pale) Cold sweats Nausea Vomitting Increased saliva Burping/flatulence Stomach awareness Headache Drowsiness/lethargy Yawning/sighing
Which sex is more likely to suffer from motion sickness?
Female
What are the age tolerances to motion sickness?
0-2 = rare 3-12 = peak 13+ = tolerance improves
How can you best manage motion sickness?
Minimise head movements Lie down Keep mind occupied Stay in the most stable part of AC (middle and window) View horizon
What is the G tolerance window?
4.5-5.5 g
What is the G continum
Weight increase Grey out Black out ALOC GLOC
When are you likely to grey out?
3-4 g
When are you likely to black out?
4-4.5 g
Do you lose consciousness at blackout?
no
What is ALOC?
Almost loss of consciousness
Short duration to 6+ g’s(approx 5 seconds)
What is GLOC?
When blood flow to brain ceases (4.5-5.5g)
What is the recovery time for GLOC?
1-5mins
After exposed to GLOC, how long and you at absolute and relative incapacation?
15 seconds each
What are symptoms of GLOC?
Euphoria Confused/disorientated Muscle spasm Seizures Light headed Amnesia (50%) Denial
What factors affect G Tolerance?
Being unprepared Rapid onset of G Fatigue Dehydration Alcohol Hypoxia Negative G
What condition can occur for Negative G?
Red out
What happens in the body when exposed to negative G?
Blood goes to head Mental confusion Headache Facial pain Fullness in head
What G protection options are there?
Anti g straining manoeuvre Anti g suits (1-1.5g) Regular exposure to G Positive pressure breathing Centrifuge training Avoiding stresses that lower tolerance
How many hours of sleep do you require?
7-8 hours
What is sleep driven by?
Circadian rhythm
What is REM and NREM?
Rapid Eye Movement
Non Rapid Eye Movement
How many stages of sleep are there?
4
With your Circadian rhythm, when is your performance best/worst?
Approx 6pm
After midnight, between 2am-5am
Which stage of sleep is your recovery stage?
Stage 4
What happens in REM sleep?
Dreaming, laying down memory
What are some affects of fatigue?
Increased irritability Impaired judgement Diminished check lists Fumbling Decreased crew coordination Lack of concern
After being awake for 17 hours, what is your approx performance %?
30% equivalent of 0.05BAC
What is sleep inertia?
Transition phase between sleep and awakeness
Can last approx 30 mins
What is the IMSAFE fitness model?
I-Illness M-Medication S-Stress A-Alcohol F-Fatigue E-Eating
What can a common cold increase the risks of when flying?
Disorientation Barotrauma Fatigue Dizziness Poor flight performance
How long do you need to be sick with a CPL before seeing a DAME?
7 days
How long do you need to be sick with a PPL before seeing a DAME?
30 days
Is malignancy a permanent grounding?
Not necessarily, can be restricted and depends on risk of sudden incapacitation
What can medications do to your performance in the air?
Impair cognitive functions Sedation Altered arousal/alertness Alter mood Impairment of vision, hearing and balance Allergic reactions Gastro upset
How long can it take to be rid of canabis effects?
24 hours
What does alcohol do to your performance?
Increase risk of dehydration
risk of hypoxia
reduced g tolerance
How long should your last drink be before flying?
8 hours bottle to throtte
What is the leading cause of total pilot incapacitation?
Gastro (58%)
When should you eat before flight?
6 hours
What is low blood sugar also known as?
Hypoglycemia
How many litres of water should you drink on a normal day?
1-2 litres
What is your blood alcohol content limit?
0.02%
What is your drugs limit for flying?
0
What does DAMP stand for?
Drugs and Alcohol Management Policy
What is the CREEP model?
C-Container R-Restraint E-Energy Absorption E-Escape P-Post crash factors
What are the four principles of survival?
Protection
Location
Water
Food
Describe immersion suits
Stops water getting into suit providing insulating layer.
Provides insulating layers only in combo with layers underneath
What is the standard survivability in 14 degrees and 6 degrees water in normal clothes?
14 = hour 6 = half an hour
What is the standard survivability in 14 degrees and 6 degrees in an immersion suit?
14= 15hours 6 = 13 hours
What is the airway freeboard and floatation angle for lifejackets?
120mm and 45 degrees
What are the three categories of hypothermia
Mild (>32)
Moderate (28-32)
Severe (<28)
How was the statue law of the Occupational Health and Safety Act passed?
Through parliament by govenment
Under the new Workplace Health and Safety Laws, a PCBU (person conduction business or undertaking) can be what?
Volunteer organisation
Sole trader
Employer
What is the main OHS document in Victoria?
OH&S Act 2004
What does Section 25 of OH&S Act 2004 state?
While at work, employee must take reasonable care for his or her own safety
What can effective consultation lead to?
More informed management decisions
Stronger commitment to decisions
More openness, respect and trust
What is a hazard?
A source or situation with a POTENTIAL for harm of human injury or ill health, damage to property, environment, or a combo
What are the three processes for risk assessment?
Identification
Analysis
Evaluation
Describe two considerations for Reasonably Practice
Likelihood of hazard or risk occurring
degree
Degree of harm that may result from hazard or risk
When is a Safe Work Method Statement used?
Used in high risk construction work
What does a Safe Work Method Statement do?
Considers and documents a risk assessment of the identified hazards for each job step and the controls
What are the hierarchy for dealing with a hazard?
Eliminate the hazard altogether
Substitute the hazard with a safer alternative
Isolate the hazard
Use engineering controls to reduce the risk
Use admin controls to reduce the risk
Personal Protective Equipment (PPE)
What is the process for OHS Management Systems?
OHS Policy Planning Implementation Measurement Evaluation
What is the framework for ICAO safety management system?
Safety Policy and objectives
Safety risk management
Safety Assurance
Safety Promotion
Who do you report workplace incidents to?
Victorian Workcover Authority
Within how long do you need to send an incident for to Victorian Workcover authority?
48 hours
How long must you keep a record of an incident notification form?
At least 5 years
When is notification required if a serious injury or death has occurred?
Phone call immediately
Written within 48 hours
What are the most common type of workplace injury?
Sprains and strains
What are the components of the spine?
Disc Vertebrae Liagaments Muscles Spinal cord
What is the best way to protect your back before you lift?
Stabilise your core
When does hearing loss occur?
When hair cells are damaged to a point that they can no longer move back and forth freely
What is the most effective way of reducing risk when dealing with heights?
Seek to perform task on ground
What personal protection equipment is to be used on an elevated work platform?
Safety harness connected to platform
Hard hat
Insulated footwear
What is the first step in the lock out-tag process?
Shut down the machinery and equipment, ensure it can’t be operated
At what height is Armstrongs Line?
65000 feet
What is Boyle’s Law?
At a constant temperature, the volume of gas is inversely proportional to the pressure to which it is subjected
What is Dalton’s Law?
Total pressure of a mixed gas is equal to the sum of partial pressures of the constituent gases
What is the oxygen pathway?
Atmosphere Trachea and Bronchi Alveoli Blood (haemoglobin) Tissues
3 factors that affect ergonomics
Manual handing
movement
posture
What is WRMSD?
Work Related Muscular Skeletal Disorder
