Human Performance Flashcards
Pilots are judged on three things
Knowledge
Skills
Attitude
8 core ICAO Competencies (CAALPAWS)
Communication Aircraft flight path management in automation Aircraft flight path management in manual process Leadership and teamwork Problem solving and decision making Application of procedures Workload management Situational awareness
3 types of safety culture
Open culture
Closed culture
National culture
James Reason’s 5 components of a good safety culture
Informed culture - knowledge share
Just culture - encouraging honesty
Learning culture - willingness to learn from events
Reporting culture - promoting the integrity to report errors/near misses
Flexible culture - organisation is willing to stray from conventional modes
Individual Aspects of a Good Safety Culture (x 3)
Leadership
Commitment
To set a good example
Number of accidents per 1 million flights (including ALL aircraft)
1.2 accidents. Human error accounts for 73% of these.
ICAO definition of Threat & Error Management (TEM)
Process of detecting and responding to threats or errors, with countermeasures that reduce or eliminate the consequence of threats or errors and mitigate the probability of errors, further errors or undesired states
5 main causes of pilot error
Directional control loss (hence intro of GPWS in 1980s) Poor judgement Air speed not maintained Poor pre-flight planning Not maintaining ground clearance
Most dangerous elements of flying
Approach
Landing
take off
Descent
Three components of TEM
Threats
Errors
Undesired aircraft states
Types of threat (LEO)
Latent - i.e. wrong way point built into system
Environmental - i.e. weather; ATC; Terrain
Organisational - i.e. poor aircraft design; operational
Types of error (PAC)
Procedural - SOPs; poor briefings; incorrect documentation
Aircraft handling errors - manual handling; automation; ground navigation
Communication errors - crew to external; pilot 2 pilot
Types of Undesired Aircraft State (AGI)
Aircraft handling - vertical/lateral or speed deviations; unstable approach
Ground Navigation - wrong taxi/hold point
Incorrect aircraft configuration - incorrect flight controls configuration
Error management strategies
Error Prevention Error reduction Error detection Error recovery Error tolerance
Error management countermeasures (x 5)
Ground proximity warning system (GPWS)
Traffic collision avoidance system (TCAS)
Planning countermeasures
Execution countermeasures - i.e. ground briefings
Review countermeasures
Safety Management Systems (SMS)
An approach to managing safety which includes the organisational structures accountabilities, responsibilities, policies and procedures.
4 key components of SMS
Safety policy
Safety assurance
Safety promotion
Safety risk management
3 areas of Safety Risk Management (which itself is a component of SMS)
Hazard ID process - reactive/proactive/predictive
Risk assessment and mitigation
Internal safety investigation
Lung partial pressure at 10,000ft
Approx half of MSL: 55mmHg
Volume % in lungs of o2 and C02
Oxygen: 14
Carbon dioxide: 5.3%
Blood oxygen saturation levels of haemoglobin (MSL/10,000ft/20,000ft)
MSL: 97.5%
10,000ft: 87%
20,000ft: falls rapidly to 65%
3 roles of the breathing system (nose)
Moistens
Filters
Warms
…the air.
Parts of the breathing system (x 6)
Nasal cavity Trachea Left/right bronchus Bronchioles Alveoli Diaphragm (helps breathing system)
Role of alveoli
Diffuse 02 and C02 through capillaries to/from the bloodstream.
External respiration (3 points)
Transfer of oxygen between environment and lungs
Breathe out c02 and water vapour
Average between 12-16 breaths per minute
Internal respiration (aka metabolism)
Occurs between blood and cells. A chemical reaction converts oxygen, glucose and other nutrients into energy (metabolisation).
Two waste products of internal respiration
Carbon dioxide c02
Water h20
Carbonic acid:
Mixture of c02 and o2 combined. Controls breathing rate.
Lung volumes (x 4)
Tidal volume: 500ml
Inspirationary Reserve Volume (inhale ability over tidal volume): 3100ml
Expiratory Reserve Volume (exhale ability over tidal volume): 1200ml
Residual Volume (left in lungs after exhalation): 1200ml
Lung capacities (x 4)
Total (Tidal + Insp + Exp + Resid): 6000ml
Vital Capacity: (Tidal + Insp + Exp): 4800ml
Inspiratory Capacity: (Insp + Tidal): 3600ml
Functional Residual Capacity (Exp + Residual): 2400ml
Hypoxia:
A deficient amount of oxygen for the body’s needs
Anaemic hypoxia:
Inability of blood to carry oxygen. caused by e.g. smoking, carbon monoxide inhalation, rapid blood loss.
Hypoxic hypoxia
Caused by shortage of oxygen to the body.
Factors affecting hypoxia (x 4)
Altitude
Rate and time of decompression
Smoking
Fitness
Symptoms of hypoxia ( x 11)
Cyanosis Euphoria Loss of basic colour/night vision Pallor Tingling of extremities Loss of judgement Headache Tunnel vision Impaired motor skills Increased breathing rate Unconsciousness and death
If hypoxia is suspected (x 3)
Apply oxygen
Request descent to 10,000ft or minimum safety altitude (MSA)
Seek medical attention
3 thresholds of hypoxic hypoxia
Reaction threshold: 0ft-7000ft: night vision affected
Disturbance threshold: 7000ft-12000ft: homeostasis affected
Critical threshold: 12000ft-22000ft: incapacitation with loss of consciousness.
Definition: Time of Useful Consciousness (TUC)
Amount of time an individual has to act with both mental and physical efficiency, measured from time at which adequate oxygen supply is lost.
TUC altitude rates
20,000ft: Seated/activity: 30 mins/5 mins
30,000ft: 1-2mins/0 mins
35,000ft: 30-90 seconds/0 mins
40,000ft: 15-20 seconds/0 mins
People already short of o2 (i.e. smokers) will have 1/2 the TUC
Definition: effective performance time (EPT)
This is equal to/less than TUC. At 40,000ft, EPT = 4-5 seconds.
O2 requirements (unpressurised aircraft):
MSL-10,000ft: air only
10,000ft-33,700ft: o2 and air mix (keeps body at MSL)
33,700ft-40,000ft: 100% o2 (keeps body at 10,000ft)
40,000ft+: 100% o2 under pressure (keeps body at 10,000ft)
Definition: hyperventilation
Breathing in excess o2. Leads to a reduction in co2 which creates less carbonic acid.
Respiratory alkosis.
Causes by lack of co2. Causes increased alkaline in blood. (Created by hyperventilation).
Symptoms of hyperventilation
Tingling of extremities Poor judgement Increased breathing rate Distress Anxiety Unconsciousness
Treatment of hyperventilation
Breathe into a bag
Slow breathing rate down
Definition: decompression sickness
Removal of pressure on cells, allowing nitrogen bubbles to leave cells into bones.
Symptoms of decompression sickness (DCS) (x 4)
Bends: bubbles on joints
Creeps: bubbles in cells
Chokes: bubbles in lungs
Staggers: bubbles in brain
When DCS occurs?
18,000ft-25,000ft. Unlikely below 14,000ft.
Factors affecting DCS (x 5)
Scuba diving (using compressed air) at depths below 30ft/10m (24hr wait period)
Scuba diving above 30ft/10m (12 hours)
Age
Altitude
Excess weight/obesity
Duration of exposure
Prevention of DCS:
By pre-oxygenation; this can mitigate DCS.
Cabin pressurisation levels?
Between 6000ft-8000ft.
Boyles Law
Volume is inversely proportional to pressure.
Affects barotrauma
Charles’ Law
Volume is proportional to temperature
Daltons Law
Total pressure is the sum of all partial-pressures.
Relates to hypoxia
Henry’s Law
Amount of gas dissolved in a liquid is proportional to the pressure on it.
Relates to decompression sickness.
Fick’s Law
Law of diffusion.
Relates of diffusion within alveoli.
Three parts of the circulatory system
Heart
Blood vessels
Blood
What is vasodilation?
Where the blood vessels widen to cool us down
What is vasoconstriction?
Where blood vessels constrict to heat us up
What are the two types of circulatory system?
Pulmonary: carrying deoxygenated blood to the lungs and oxygenated blood to the heart.
Systemic: carry oxygenated blood to the body and deoxygenated blood back to the heart.
What is the composition of blood?
Red blood cells
White blood cells
Platelets
Plasma
Where is blood made?
In bone marrow
What do coronary arteries do?
They supply the heart with o2 and glucose
What do the coronary veins do?
They remove waste products (carbonic acid) from the heart
What is the pulse rate for an average healthy adult?
70-75 beats per minute
What are the four main factors that affect heart rate?
Carbon dioxide
Adrenaline
Glucose
Exercise
What is stroke volume?
The volume of blood pumped by the left ventricle in one beat. The average is 70ml.
What is cardiac output?
The volume of blood pumped by the left ventricle in beat per minute.
It is measured by Pulse Rate x Stroke Volume. Average is 5040ml per min.
What is coronary heart disease?
It is caused by a restriction of blood (o2 and glucose) to the heart. Coronary arteries become blocked.
What is angina?
Pain associated with coronary heart issues.
What is a heart attack?
Caused by a total blockage of a coronary artery, which starves the muscle of oxygen.
What are symptoms of a heart attack?
Pale Pain in chest Pain down left side of body Cold/clammy Shortness of breath.