SACAA CPL · Subject 040 · Revision Notes
Every fact below is the marked answer from the 1 417-question bank, phrased the way the exam phrases it. Sections are ordered by how many questions the bank actually asks — read top to bottom and you are spending time where the marks are.
Twenty-four cues that answer a question outright. If you recognise the cue, you do not need to think about the options.
Eliminate these on sight, in any question:
The single biggest topic in the bank. Almost every stress question resolves to one idea: stress is subjective.
The master key
Whenever a question asks what determines, triggers, or sets the level of stress, the answer contains "the subjective evaluation / individual interpretation of the situation and one's ability to cope with it." Every phrasing variant of this is a marked answer.
| Stress is | A normal, necessary adaptation phenomenon — the best mechanism man possesses for responding to situations he faces |
| A stress reaction is | The non-specific response of the body to every demand placed on a person |
| A stressor is | An external or internal stimulus interpreted by the individual as stressful |
| Two inputs to the stress model | Perceived demand of the task + perceived ability to complete it |
| Distress | What you remain in if coping is impossible; also what prolonged/extreme stress produces |
| Physical stress occurs when | Outside conditions strain the homeostatic mechanisms of the body |
| Homeostasis | Maintenance of the body's internal equilibrium |
| Psychosomatic means | Mental/emotional stressors manifest as physical reactions (not the reverse) |
Three phases, in order: Alarm → Resistance → Exhaustion. Associated with the ANS (Autonomic Nervous System). It can activate in response to an imaginary threat.
| Phase | What happens |
|---|---|
| Alarm | Adrenaline → massive glucose release, pulse ↑, BP ↑, rate and depth of breathing ↑, arousal ↑. Recognises the stressor and prepares the body for action. Stress resistance decreases. |
| Resistance | Cortisol converts fat into sugar, prolonging energy mobilisation. Activation of the ANS. Psychosomatic disorders appear if prolonged. |
| Exhaustion | Body must be given time to eliminate the waste products generated in the two preceding phases. |
Watch the wording
Resistance phase characteristics = "1 and 4" (ANS activation + psychosomatic disorders). Testosterone is a distractor — it is cortisol. Alarm phase = "1, 2, 3" — "activation of the digestive system" and "cortisol to mobilise attention" are false for alarm.
| Physiological / environmental | Psychological |
|---|---|
| Noise · vibration · acceleration · extreme temperature (hot or cold) · humidity · sleep deprivation · severe thirst · hunger · radiation | Conflict · a death · loss of spouse or partner · divorce · loss of job · credit card debt · administrative problems · sense of inadequacy |
"Environmental" in a question means physiological. Most serious non-professional stressor = death of a spouse or partner.
| The curve | Inverted U (also stated as an inverted V). Deep sleep at one end, extreme panic at the other; optimum at the mid-point |
| Best performance at | Optimum arousal — not maximum |
| High arousal gives | Faster but less accurate responses; narrows the span of attention |
| Best placed to cope with a difficult task | Below the "break point" |
| The "Break Point" | The point after which, if stress keeps rising, performance is degraded |
| Effect of stress on performance | 2, 3, 4 — optimum arousal gives optimum performance; excessive stress weakens it; insufficient stress also weakens it. It does not always reduce performance |
| "Define arousal" | All of the above is correct |
| Fixation / tunnel vision expected when | Stress is high |
| Two pilots, same situation, opposite reactions | The arousal level of both will be raised |
| Physiological responses | Sweating, dry mouth, breathing difficulties; insomnia, loss of appetite |
| Easily observable signs | Perspiration, flushed skin, dilated pupils, fast breathing |
| Cognitive effects | 1, 3, 4, 6 — excessive haste · a complete block · risk of focusing on one aspect · increased rate of mistakes. (Memory does not improve; decision-making does not get easier) |
| Behavioural effects | 1 and 4 — aggressiveness and withdrawal |
| Overstressed pilot shows | All four — mental blocks/confusion/channelised attention · resignation, frustration, rage · deteriorating motor co-ordination · high-pitched voice and fast speaking |
| First cockpit tool to suffer | Cockpit communications |
| Regression | Correct actions forgotten, substituted for procedures learnt in the past |
| Stress affects | Attention, concentration, memory, judgement — all of them |
| Stressors are | Cumulative — they accumulate and escalate (as do errors, CO effects and human conflict) |
| Succeeding at a stressful task | Next time the stress experienced is less |
| Stress management programmes | The prevention and/or removal of stress |
| Anticipated stress or time pressure | A strategy of preparing decisions |
| In-flight stress | Use all available crew resources |
| Chronic stress | A concept approaching the entire body and improving wellness |
| To limit stress generally | Maintain competence by practising skills and learning from past experience |
| Cognitive coping | Ignoring or rationalising the stress factor |
| Overload during flight | 1, 2, 4 — use own reserves · divide tasks · drop tasks and stick to high-level priorities |
| Workload depends on | The current situation, the pilot's expertise, and the ergonomics of the system |
| Acceptable workload | 2, 3, 4 — about 60% of crew resources (not 90%) |
| Two categories | Acute and chronic (also worded "chronic short-term and acute") |
| Symptoms | Tiredness · slowed reactions · diminished motor skills · tunnelled concentration · diminished accommodation · long-term memory access problems |
| Causes | Sleep loss · jet lag · boredom · low external stimulation — all of them |
| Stress vs fatigue | Stress may be positive; fatigue is always negative |
| A fatigued pilot shows | Increased irritability |
| Fatigue and stress | Lower the tolerance to hypoxia |
| Acute fatigue | Has physical roots — "acute fatigue generally has psychological roots" is the INCORRECT statement |
| Tiredness | A subjective sensation which may result in hypovigilance / poor management of intellectual capabilities. It reduces the ability to manage multiple matters |
Fatigue — the option that may be missing
If "acute and chronic" is NOT among the options, choose "None of the answers are correct." A version circulates offering only high/low, light/chronic, heavy/light, acute/heavy.
| Vigilance is | Sustained attention — consistent monitoring without lapses. Example: continuously scanning for traffic on a long flight |
| Causes of hypovigilance | 1, 2, 3 — monotony of the task · tiredness/need for sleep · lack of stimulation. (Not excessive stress) |
| Signs of losing vigilance | 1 and 3 — decrease in sensory perception · sensation of muscular heaviness |
| Remedies | 1 and 4 — keep active open communication + organise rest periods. Never amphetamines or reducing light |
| Night cruise, low workload | Increase the cockpit lighting to prevent low vigilance |
| Hypovigilance can occur | At any moment of the flight |
| Human underload example | An unexpectedly poor landing at a familiar airfield in perfect weather |
"What is hypovigilance?"
The marked answer describes an extremely agitated state of panic — which is actually hypervigilance. The bank has it wrong but it is marked correct, and the other three options (rapid breathing from stress/fear) are all wrong. Pick the panic/agitation option.
| Type | Description | Main risk |
|---|---|---|
| Autocratic (= authoritarian) | The captain's excessive authority considerably reduces communications and therefore the synergy and cohesion of the crew | Captain becomes overloaded in high stress or emergency. Co-pilot reacts with 2, 3, 4: scapegoat feeling, delayed reactions, disengagement |
| Laissez-faire | A passive approach by the captain allows decisions, choices and actions by other crew members; makes few suggestions or decisions | Inversion of authority |
| Synergistic (the "ideal") | Decisions taken by the Captain with the help and participation of the crew. Characterised by 1 and 4: decisions taken by the captain but prepared by the crew; fluid consensual leadership boundaries | — |
| Self-centred | Each does his own thing without noting what others are doing, assuming everyone is aware. High independence granted by the captain quickly leads to tension | Co-pilot ignored → disengagement, delayed responses, aggression / scapegoat effect |
A non-synergetic cockpit is characterised by withdrawn crew members and unclear communication.
| Synergy | Co-ordinated action of all members towards a common objective, where collective performance exceeds the sum of individual performances. As maths: 1 + 1 > 2 |
| Building synergy | Built from the start of the mission (briefing) and maintained until it ends (debriefing) |
| Co-action | Working in parallel to achieve one common objective (one version instead marks the synergy definition — see Traps) |
| Co-ordinated co-operation | 1 and 3 — allows synergy between captain and co-pilot; communication synchronises actions and distributes responsibilities |
| Advantages of co-ordination | Redundancy, synergy, clarification of responsibility |
| Teamwork advantages | 1, 3, 5, 6 — workload lessened · safety enhanced · work stress reduced · improved decision-making. (Not conformity to group norm, not risky shift) |
| What optimises crew co-operation | All three — shared common task · confidence in each other's capability · precise definition of functions |
| Team spirit depends on | Both pilots respecting each other and striving for the same goals |
| Crew performance quality depends on | The social competence of individual team members |
| Discussing private matters in the cockpit | Can improve team spirit |
| Too much cohesion | Groupthink, which can be negative |
| Very high ambition / need for achievement | Disturbs the climate of co-operation |
| Pilots take greater risks when | Part of a group and feeling observed and admired (e.g. air shows) |
| Two most important positive attributes | 2 and 3 — exemplary role-behaviour and mastery of communication skills |
| Primary functions of leadership | Regulating information flow, directing and co-ordinating crew activities, motivating crew, decision making |
| Leader behaviour depends on | The situation, the goals, and the composition of the group |
| Friendly, encouraging, compromising, trusting captain | Low task-orientation, high relationship-orientation |
| Ideal professional pilot | Both person and goal oriented |
| Inexperienced but highly motivated co-pilot | Inappropriate: letting him fly and observing without any comments |
| Status vs role | Role defines, via behaviour, the functions to be performed; status defines the hierarchical position and its recognition by the group |
| Status/role conflict examples | A senior Captain acting as co-pilot to a junior Captain; two Training Captains flying together |
| Informal roles | Evolve as a result of interactions among crew members |
| Group norms | Regulate the interaction and behaviour between group members |
| Overall responsibility for the flight | The Pilot in Command. Flight safety generally = everyone involved |
| Antidotes / resolution strategies | 1, 2, 4 — seeking arbitration · actively listening · becoming aware of cultural influences. (Never move the conversation to an emotional level) |
| Best single behaviour | Active listening |
| Democratic/co-operative leader in conflict | Clarifies the reasons and causes with all persons involved |
| Conflict management involves | Participation of all involved parties in finding an acceptable collective solution |
| Resolution process | All four — realise and accept the conflict · verbalise mutual expectations · search for common agreements · express one's own viewpoint |
| Consequences of conflict | 1, 2, 4 — work performance decreases · communication quality decreases · fewer available resources used |
| Feeling unfairly treated by the Captain | Point out the problem, concentrate on duties, clarify at a more appropriate time |
| Captain smokes and dismisses you | Do not discuss further; return to it at the de-briefing |
| Intra-personal conflict | Conflict within oneself |
| Differences of opinion are | Helpful |
| Effective communication | Transmission of a message from one brain to another with a minimum of change |
| Depends most heavily on | The sender |
| Feedback | A message is measured and corrected against the original meaning; the element confirming a message was received and understood, without adding new information |
| Feedback rules | Should always relate to a specific situation. It gives information about the sender, the sender's intentions and the situation — all three |
| Non-verbal communication | Constitutes approximately 70% of human communication · supports verbal communication · can substitute for oral speech (all three appear as answers) |
| Metacommunication | Approximately 80% of communication is achieved by factors other than words — the tools other than the actual words that complement them |
| Why word choice matters more in a cockpit | Loss of body language |
| "One cannot NOT communicate" | Being silent and inactive are non-verbal behaviours which express meaning |
| Most sensitive to | Workload and interruptions. Influenced by workload, noise and voice |
| Increased workload leads to | Shorter and less frequent exchange of information |
| Communication in the cockpit | Uses up resources, limiting resources for work in progress |
| Professional language | 1 and 4 — limited vocabulary · context provides meaning and reduces ambiguity. Gives quick comprehension and simplified grammar |
| Main cause of ground-to-crew message failure (NASA) | Listening errors |
| Making communication effective | Only 2 — send information in line with the receiver's decoding abilities |
| Sender who thinks the receiver is incompetent | Only 3 — tends to simplify the content of sentences |
| The recipient must | 3 and 4 — be able to reject/postpone if too busy · stabilise or finish a challenging manoeuvre first |
| Implicit ("between the lines") communication | Sender can always claim to have been misunderstood |
| Glass cockpit | Communication does not lose its importance; automation means co-ordination calls for even greater effort |
| English | All pilots should master it — aviation needs one common language |
| Words heard vs spoken | Listen to 900 per minute, speak 125 |
| Purpose of a briefing | Done systematically to refresh memory and co-ordinate actions; initiates procedures for situations that are most likely, risky or difficult |
| Qualities of a good briefing | 2, 3, 4 — standard type, reusable · short and precise · understandable to the other crew |
| Pre-flight general briefing emphasises | Particular requirements in crew co-ordination and co-operation due to specific circumstances |
| Checklist design | 1, 4, 5 — subdivide long lists · panel scan sequence · redundancies for critical points. Most important items at the beginning (attention is focused there) |
| Checklist use | Must not be done simultaneously with other actions |
| Checklist before start contributes to | Safety — draws attention to flight-related tasks, reducing distraction from personal stress |
| Check procedures matter most when | Flying an unfamiliar type and experiencing mental pressure |
| Action plans / SOPs | Must be shared by the crew and updated at each modification to maintain maximum synergy |
| Pre-thought action plans | 1, 2, 4 — ease access to information · prepare for a coming situation · define a framework and probable strategy |
| Planning / anticipation allows | 1, 2, 4 — precise reference framework · avoid saturation of the cognitive system · activate necessary knowledge |
| Standardising behaviour | Reduces errors even under adverse circumstances |
| Interrupting the Captain for a sound reason | Afterwards, remind him of his last action before the interruption |
| End Deterioration Effect ("home-itis") | Tendency to sudden, imperceptible errors shortly before the end of a flight |
| Definition | Perception of the elements in the environment within a volume of space and time, comprehension of their meaning, and projection of their status in the near future |
| Short form | "When a pilot's perception equals reality" |
| SA skills | Monitor, evaluate, anticipate |
| To maintain good SA | 2, 3, 4 — gather data from every source · question whether your hypothesis still fits · test your hypothesis. Never believe only your own interpretation |
| Most common SA problems | All of the above |
| Too high a workload | Loss of situational awareness — a contributing factor in many accidents |
| CRM / MCC training is designed to | Improve the quality of crew performance — developing effectiveness by improving attitudes toward flight safety and human relationship management |
| CRM in practice, e.g. | Expression of doubts or a different opinion (long version: for as long as the doubt cannot be rejected on the basis of evidence) |
Every question in this section
The cure is always the instruments — "believe the instruments", "rely on instruments", "maintain an effective instrument cross-check", "depend on the instruments". The seat-of-the-pants sense is completely unreliable in IMC.
| Organ | Senses | Location |
|---|---|---|
| Semi-circular canals (three) | Angular acceleration — roll, pitch and yaw | Inner ear |
| Otoliths (utricle + saccule) | Linear acceleration and gravity | Inner ear (the vestibule) |
| Cochlea | Sound | Inner ear |
The vestibular apparatus consists of "the semi-circular canals and the otoliths" — or "semi-circular canals, utricles and saccules". Both are marked correct. Composition = 2, 3, 4 (saccule, utricle, three semi-circular channels — not "two ventricles"). The cupula bends when rotation begins because the endolymph lags behind the accelerated canal walls.
Orientation in flight uses all four: eyes · utriculus and sacculus · semi-circular canals · seat-of-the-pants sense.
| Illusion | Cause and sensation |
|---|---|
| Somatogravic | Otoliths. Forward acceleration = illusion of climbing / pitching up (backward displacement of the otolithic membranes). Deceleration = sensation of nose-low / descending. Gives "a false impression of climbing or descending" |
| Somatogyral / the Leans | Semi-circular canals. Caused by prolonging a turn — and also by reducing bank following a prolonged turn. Both are marked answers |
| Graveyard spin | A spin in which the pilot, on recovery, tends to re-enter the spin due to the somatogyral illusion where the vestibular system no longer senses radial acceleration. Stopping the rotation feels like starting a spin in the opposite direction |
| Coriolis | Simultaneous stimulation of several semi-circular canals — caused by a head movement during a turn. The instrument panel seems to tumble. Classic scenario: bending down to pick up a pencil in a tight turn |
| Pilot's vertigo | Either "dizziness / tumbling sensation caused by contradictory impulses to the CNS" or "a sensation of rotation due to multiple irritation of several semi-circular canals at the same time". Both marked. Result of the Coriolis effect |
| Flicker vertigo | Flashing light — from strobes in cloud or sunlight through rotor blades. Causes spatial disorientation and/or nausea. Cure: switch the strobe lights off |
Rolling out of a prolonged level turn → sensation of turning in the opposite direction. Rolling out of a co-ordinated level turn → descending and turning into the opposite direction. Starting a co-ordinated level turn → belief you are climbing (pressure receptors feel increased pressure along the body's vertical axis, the same sensation as a climb).
Prevention: avoid steep turns and abrupt manoeuvres, minimise head movements, maintain an effective instrument cross-check. In good visibility, prevent vertigo by looking at the horizon.
| Situation | You FEEL | You FLY | Result |
|---|---|---|---|
| Narrow runway | Higher than you are | Low / flat approach | Undershoot — land short |
| Wide runway | Lower than you are | High approach | Overshoot — high/early round-out, land long |
| Upsloping runway or terrain | Higher than you are | Low approach | Land short |
| Downsloping runway or terrain | Lower than you are | High approach | Land long |
| Black hole (night, water/desert/jungle, no lights, no VASIS) | Too high and too far away | Drops low, "ducks under" | Land short |
| Fog, haze, mist, snow, rain | Objects further away than reality | Delays descent, then steepens | Steep approach |
45 m → 25 m runway = low approach with undershoot · 27 m → 45 m runway = high approach with overshoot
Threshold area descending towards the threshold (downslope terrain) → approach is higher than normal, long landing. No information about runway dimensions or approach terrain → make an instrument approach and be aware of the illusory effects.
| Autokinesis | Apparent movement of a static single light stared at for a long period in the dark — without a frame of reference. Can make a star look like another aircraft. Prevention: look for additional references inside and outside the cockpit, using peripheral vision |
| Relative movement | Without external references, the sensation that your vehicle is moving when it is the one alongside that is moving |
| Taxiing illusions | Caused by relative movement and cockpit height above the ground |
| Tree-size illusion | Illusion of greater height when suddenly flying over small trees after prolonged flight over tall trees |
| Empty field myopia | Caused by a lack of distant focal points. Prevention: short sharp scans, or periodically focus on a distant object such as a wing tip or cloud edge |
| Flash blindness | Protection: all four — turn cockpit lights up, look inside, wear sunglasses, use face curtains |
| Low contrast generally | Difficult to estimate the correct speed and size of approaching objects; perception of distance and speed is difficult |
| Fading light source in fog/haze | Sensation that the source of light moves away from him |
| Spatial disorientation is | False perception of orientation of the aircraft with respect to spatial references. Most likely when the brain receives conflicting information and the pilot does not believe the instruments |
| Most probable reason | A poor instrument cross-check and permanently transitioning back and forth between instruments and visual references |
| More likely when | 1, 2, 4 — flying in IMC · frequently changing inside/outside references · approaching over still water at night or having a cold (whichever appears) |
| Proprioceptive / seat-of-the-pants | Receptors in muscles, tendons and joints plus subcutaneous pressure receptors. Both: "reacts to pressure on skin, joints and muscles" and "senses the seat-of-the-pants movements". Completely unreliable for orientation in IMC |
| Kinaesthetic sense | Does not orient you to your surroundings — informs you of the relative motion and relative position of your body parts |
| Illusions from perceptive conflicts | Sensory conflict on the vertical and horizontal between the vestibular and the visual system |
| Which conflicts are visual/vestibular? | 1 and 4 — illusions about aircraft attitude, and illusions of rotation. (Autokinesis and size/distance are visual only) |
| Motion sickness systems | 2, 3, 4, 5 — vestibular, vision, proprioceptive, gastro-intestinal (or 2, 3, 4). Hearing is never included |
| Air-sickness is | A sensory conflict within the vestibular system with nausea, vomiting and fear. More likely when the passenger is afraid and/or demotivated |
| Preventing passenger air-sickness | All four — avoid turbulence · avoid rough weather · seat them close to the centre of gravity · give pertinent information |
| Vibration | 1–100 Hz causes tuned resonance of body parts; 0.1–2 Hz upsets the vestibular apparatus (air-sickness); blurred vision is resonance of the eyeballs |
| Sensory threshold | Stimuli must be of a certain strength for receptors to pick them up. Raising the threshold means less sensitivity |
| Protection against illusions | Comprehensive briefing and de-briefing |
| Store | Capacity | Duration | Key facts |
|---|---|---|---|
| Sensory | — | Lost within 10–20 s unless rehearsed | First stage of processing is sensory stimulation |
| Short-term / working | About 7 items | About 20 s | Limited in time AND size. Very sensitive to interruptions which may erase content. Lets you hold a clearance long enough to write it down |
| Long-term | Unlimited | Effectively unlimited | Main limitation is retrieval / loss of access unless information is recalled regularly |
Short-term memory limits = 1, 3, 4 (sensitive to interruption · limited in size · lost in ~20 s). It is not "difficult to access".
Long-term memory stores semantic, episodic and procedural memory — also stated as descriptive, rule-based and schematic knowledge. Correct combination is 1 and 4: information is stored in those forms, and pre-activation / frequency of recall reduces access time. It is influenced by experience, repetition, suggestion, desires and expectations.
| Episodic memory | Memory of events, held in LTM, can be influenced by suggestion |
| Semantic memory | Meaning of words and general knowledge; lasts longer and is more accurate than episodic |
| Motor programmes | Stored routines enabling patterns of behaviour to be executed without continuous conscious control |
| To speed LTM access | Mentally rehearse information before it is needed |
| Mnemonics | Help to increase retention of information |
| Knowledge acquired through | Sight 75% · hearing 13%. Also stated: 70% of information enters via the visual channel |
Long-term memory question
"Which answers are correct concerning Long Term Memory?" — statement 4 ("LTM is where motor programmes are kept") is true in reality, but the bank marks "1 only is correct". Answer 1 only.
| Two types of attention | Selective and divided |
| Divided attention | "Alternative management of several matters of interest" or "the management of several matters of interest dealt with individually one after the other" — both marked. As statements: 1 and 2 correct, 3 and 4 false |
| Attention (definition) | The ability to detect relevant information not presented in an actively monitored input channel |
| Cocktail party effect | The ability to pick up relevant information unintentionally. Associated with attention mechanisms |
| Factors guiding attention | 1, 3, 4 — level of automation of behaviour · salience of the information · expectations |
| Selective attention is required | Because of the limited capacity of the central decision maker and working memory |
| Two cognitive tasks at once | Sharing of resources causes performance on each to be reduced. Cognitive resources are limited — it is impossible to perform two attentional tasks at the same time |
| Tasks possible simultaneously | Maintain manual straight and level flight and solve a problem (one is automated) |
| Wickens' theory | The brain has different reservoirs of resources for the information-gathering, information-processing and action phases |
| Omitting to monitor fuel while fighting the aircraft | A lack of attention due to distraction |
| Perception is based upon | Information received as well as past experience and knowledge |
| Most dangerous characteristic | It is frequently extremely resistant to correction (same for a false mental model) |
| Incorrect perception | Can be highly persuasive |
| Adverse effect of expectations | They guide the focus of attention towards a particular aspect while alternatives are neglected |
| Basis of all perceptions | The intensity of the stimuli |
| Gestalt laws | Basic principles governing how objects are mentally organised and perceived |
| Mental models / schemes | Built on past experience and learning; memorised representations of procedures and situations reactivated at will |
| Cognitive illusions | Associated with the task of mental construction of the environment |
| Reflex | A stereotyped, involuntary reaction of the organism to stimulation of receptors |
| Anderson — three stages of skill acquisition | Cognitive → Associative → Automatic (also "autonomous") |
| Rasmussen — three control modes | Skill-based → Rule-based → Knowledge-based. Skill-based errors are routine errors; rule-based errors are errors of technical knowledge (application of a poor rule / poor application of a good rule) |
| Flying a co-ordinated turn | Skill-based behaviour. Following a familiar VFR approach with no surprises = skill-based too |
| Choosing when to select flaps | Skill and/or rule based (some versions: skill based) |
| Rule-based → knowledge-based when | The known rules are unsuitable for the problem posed |
| Automated → rule-based when | Detecting that automated behaviour will no longer lead to the intended outcome |
| When a rule resolves the situation | Actions return to an automatic mode |
| More automation of behaviour | Less conscious attention required → frees mental resources |
| Learning is | Any lasting change of behaviour due to practice and experience; facilitated by reinforcing successful performance and feedback on one's own performance |
| Mental training / ideomotor simulation | Most important for the acquisition of complex perceptual motor skills; helpful at all levels of proficiency |
| Procedural consistency | Developing procedures makes pilots more effective and more reliable |
| Information | 2 and 3 — intended to reduce uncertainty for the receiver; measured in bits |
Definition: a state of oxygen deficiency in the body — "any condition where the oxygen concentration of the body is below normal limits, or where the oxygen available cannot be used due to some pathological condition". Caused by reduced partial pressure of oxygen in the lung, itself caused by decreased atmospheric pressure. Explained by Dalton's Law.
| Type | Cause |
|---|---|
| Hypoxic | Low ppO₂ — altitude without oxygen, oxygen system failure, loss of pressurisation |
| Hypaemic | Blood cannot carry it — anaemia, CO poisoning, blood donation, smoking |
| Stagnant | Blood not flowing — +Gz pooling, cold, heart failure |
| Histotoxic | Cells cannot use it — alcohol, drugs, cyanide, hangover |
| Most dangerous for flight safety | Impaired judgement — long version: "impaired judgement, disabling the pilot to recognise the symptoms". Also worded "degradation of reasoning and perceptive functions" and "euphoria and impairment of judgement" |
| Standard symptom list | Visual disturbances, lack of concentration, euphoria · fatigue · headache · dizziness · lack of co-ordination · tingling · cyanosis · blurred and/or tunnel vision |
| Symptoms 1–5 questions | 1, 2, 3 — fatigue, euphoria, lack of concentration. Pain in the joints (DCS) and suffocation sensation are always false |
| Early symptoms | 1, 3, 4 — euphoria, lack of concentration, visual disturbances. Breathing rate increases, it does not decrease |
| Beginning of hypoxia | 1, 2, 4 — blue lips and fingernails · euphoria · unconsciousness. (Not flatulence) |
| During explosive decompression | Increase in heart and respiratory rates, euphoria, impairment of judgement, memory disorders |
| Crew with blue lips, mental disturbance, tingling, reduced peripheral vision | Hypoxia |
| Shared with hyperventilation | Tingling sensations in arms or legs |
| Unique to hypoxia | Cyanosis — blue colour of finger nails and lips |
| 5 000 ft | Hypoxia begins to affect night vision — the function most sensitive to lack of oxygen (rods more than cones) |
| 6 000–7 000 ft | Threshold for compensatory reactions — the body starts remarkable measures to compensate for falling PO₂ |
| 8 000 ft | Short-term memory can already be affected; night vision affected above this cabin altitude |
| 10 000 ft | Limit below which oxygen saturation is unlikely to affect judgement. Use supplemental oxygen above 10 000 ft. ppO₂ falls below the critical value of 55 mmHg |
| 10 000–12 000 ft | Healthy people can usually compensate up to here |
| 12 000 ft | Hypoxic hypoxia — short-term memory impairment starts. Symptoms: headache, fatigue, dizziness, lack of co-ordination |
| 15 000 ft | Night vision reduced >25% — the compensatory stage |
| 20 000 / 21 000 ft | The critical threshold — both numbers are marked correct in different questions. Pick whichever is offered |
| below 3 000 m | The indifferent phase — altitude hypoxia on ambient air should not occur |
| Compensating hypoxia | 1, 2, 4 — descend below 10 000 ft · breathe 100% oxygen · reduce physical activity. Never "climb to or above 10 000 ft" |
| Prevention at altitude | Pressurise the cabin to achieve oxygen saturation in the blood of more than 90% |
| Passenger with blue lips at 9 000 ft | Reduce altitude and supply oxygen |
| Acuity dropped at 10 000 ft at night | Breathe extra oxygen through the mask |
| Severity depends on | All four — rate of decompression · physical fitness · flight level · individual tolerance. Sensitivity varies from person to person |
| Lower your tolerance | Fatigue, stress, smoking, alcohol, obesity, sleep deprivation, exhaustion |
| Why solo flight is dangerous | The first signs are hard to detect (hypoxia of the brain) so the pilot may not react in time |
| Most dangerous incapacitation | One that develops slowly and gradually — insidious |
First action, every time
Don your own oxygen mask — even when the other pilot is incapacitated. Then maintain aircraft control and descend below 10 000 ft.
TUC = the length of time during which an individual can act with both mental and physical efficiency and alertness, measured from the moment he loses his available oxygen supply. It is the same as EPT / Effective Performance Time — if both options appear, take "both are correct". It varies individually and depends on cabin pressure altitude, and varies with 1 and 3: physical activity of the crew, and the strength/time of the decompression.
| Altitude | Standard table | Answers actually marked in the bank |
|---|---|---|
| 20 000 ft | 5–10 min | — |
| 25 000 ft | 2–3 min | "Between 3 and 5 minutes depending on physical activity" |
| 30 000 ft | 45–85 s | "Between 45 seconds and 1 minute 30 seconds" |
| 35 000 ft | 30–45 s | 45 s (seated) · 30–90 s · 30–40 s · 30–60 s — all four appear |
| 37 000 ft | — | 18 seconds |
| 40 000 ft | 18–30 s | About 12 seconds |
| 43 000 ft | — | 5–15 seconds |
Method for any TUC question
Estimate from the standard table, then pick the closest option offered. Above 30 000 ft think "under a minute"; at 40 000 ft+ think "seconds".
| Cause | Nitrogen coming out of solution — over-saturated nitrogen gas molecules in the body tissues. Explained by Henry's Law: the quantity of gas dissolved in a fluid is proportional to the pressure of that gas above the fluid |
| Occurs from | Above 18 000 ft — as statements, 1 and 3 (above 18 000 ft; rate of climb >500 ft/min exceeding 18 000 ft). In airline ops, may develop after decompression from 7 000 ft cabin to 30 000 ft |
| Bends | Pain in the joints — the primary and most frequent symptom |
| Chokes | Gas bubbles in the lungs / respiratory system |
| Creeps | Gas bubbles under the skin — itching, rash |
| The Leans | NOT a form of DCS — it is a vestibular illusion. It is the odd one out in "Bends, Chokes, Creeps, Leans" |
| Full symptom list | Bends, chokes, skin manifestations, neurological symptoms and circulatory shock. They can appear with a delay after the aeroplane is on the ground |
| Risk factors | Age, obesity and scuba diving (not body height) |
| Action on symptoms | 2, 3, 4 — descend to the higher of 10 000 ft or MSA and land as soon as possible · breathe 100% oxygen · get medical advice about recompression after landing |
| Prevention | 1, 2, 4 — avoid cabin altitudes above 18 000 ft · keep cabin below 8 000 ft · breathe 100% oxygen for 30 min before and during flight (denitrogenation). Never physical exercise |
| Joint pain hours after FL300 decompression | Ask for medical advice (flight surgeon) — it is DCS |
| Rapid decompression, no symptoms | Seek prompt aeromedical advice; wait 12 hours before the next flight |
| Dysbarism | The various medical problems caused by gas expansion induced by decreased barometric pressure |
| Cabin pressure in airline operation | Normally not exceeding 6 000 to 8 000 ft |
| A pressurised cabin prevents | 1, 2, 3 — decompression sickness · gas expansion in the intestines · hypoxia. (Not coronary disease) |
| Purpose of pressurisation | All of the answers are correct |
| Gradual depressurisation 12 000–18 000 ft | Loss of co-ordination with fatigue and headache |
| Above 10 000 ft, explosive decompression | Don an oxygen mask and descend below 10 000 ft |
| Scuba >10 m depth | Wait 24 hours before flying. Can cause DCS even below 18 000 ft. Flights immediately after are forbidden |
| Snorkelling | No waiting time |
| Survival at 40 000 ft depressurised >10 min | Yes — provided 100% oxygen is immediately available from masks |
| Blood pressure (normal adult) | 120 / 80 mmHg (systolic/diastolic), measured in the artery of the upper arm at heart level |
| Pulse at rest | 60–100 bpm (also stated 60–80) |
| Breathing rate at rest | 16 cycles/min — range 12–20 |
| Tidal volume | 500 ml |
| Cardiac output at rest | 5 litres/min (= heart rate × stroke volume) |
| O₂ saturation at sea level | 98% |
| CO affinity for haemoglobin | 210–250× that of oxygen |
| External respiration | Gas exchange in the alveoli — O₂ into the blood, CO₂ diffuses from blood into the lungs |
| Internal respiration | A metabolic process inside the cells where oxygen is used and carbon dioxide produced. O₂ from blood → tissues, CO₂ from cells → blood |
| The mechanism | Diffusion — driven by the partial pressure / diffusion gradient. Oxygen diffusion into cells depends on their ppO₂ gradient |
| Gaseous exchange depends on | All four — diffusion gradients · permeable membranes · ppO₂ in alveolar air · acid-base balance |
| Rate and depth of breathing is controlled by | The amount of CO₂ in the blood — via receptor cells in the brain |
| Increased CO₂ in the blood | Shortness of breath or an increased respiratory rate — both marked |
| Components of the respiratory system | Oral-nasal passage, pharynx, larynx, trachea, bronchi, alveoli |
| Total lung volume | All four — tidal + inspiratory reserve + expiratory reserve + residual volume |
| Purpose of respiration | Intake of O₂ for the metabolic process in living cells |
| Expired air contains | More carbon dioxide than inspired air |
| Survival at any altitude requires | Enough oxygen, pressure and heat |
| Red cells | Transport oxygen — via haemoglobin inside them |
| White cells / platelets | Immunity / coagulation |
| Plasma | The part of blood without cells |
| Pulmonary artery contains | Oxygen-poor, carbon-dioxide-rich blood |
| Heart muscle is supplied by | The coronary arteries |
| Capillary walls are permeable to | Gases |
| Circulation does | All three — transports O₂ to cells · withdraws waste · conveys nutrients. Also transports information by chemical substances (hormones) |
| Blood pressure depends on | All four — work of the heart · peripheral resistance · elasticity of arterial walls · blood volume and viscosity |
| Pressoreceptors | Measure changes in blood pressure; located in the carotid and aortic arterial vessels |
| When pressoreceptors sense a BP drop | 2, 3, 4 — arterioles constrict · cardiac output increases · heart rate rises. (Respiration does not) |
| Saturation decreases with | 1, 2, 3 — decreasing air pressure · CO poisoning · increasing altitude |
| Anaemia | Not enough functional haemoglobin |
| After donating blood | Increased susceptibility to fainting (low BP from lost volume) and to hypoxia |
| CNS | Brain and spinal cord. Vision is processed at the cortex. Handles reception of stimuli, transmission of nerve impulses, activation of muscle mechanisms |
| PNS | Passes information from sensory inputs to the CNS through sensory and motor nerves |
| ANS | Controls breathing, digestion, heart rate — no voluntary control. Regulates sweating, arterial pressure, body temperature and the General Adaptation Syndrome |
| Brain's main parts | Brain stem, cerebellum, cerebrum. The cerebellum is the reflex centre for co-ordination of equilibrium |
| Neurones / synapse | Neurones are the conducting elements; the synapse is the functional connection between them. Nerve cells are capable of both "slow generalised activity" and "efficient rapid activity" |
| Metabolism | "The transformation by which energy is made available for the uses of the organism" or "the generation and utilisation of energy by the body's cells and tissues" — both marked |
| Energy comes from | Carbohydrates, protein and fats (as statements: 2 and 3 — not minerals or vitamins) |
| Metabolic waste product | Water or carbon dioxide — both marked in different questions. Water is lost via skin, lungs and kidneys |
Definition: an excessive rate and depth of respiration leading to an abnormal loss of CO₂ from the blood — simply "an increased lung ventilation". Symptoms are caused by a shortage of CO₂, which makes the blood more alkaline (acidity reduced, carbonic acid falls).
| Causes | Fear, anxiety and distress; overstress, strong pain, pressure breathing, high arousal. As statements: 1, 2, 3, 4 correct, 5 (jogging) false — jogging is a genuine physiological need |
| Symptoms | Dizziness, tingling in fingers and toes, nausea, blurred vision, muscular spasms, rapid heart rate, unconsciousness |
| Not a symptom | Cyanosis — that is hypoxia only |
| Cure | Control the rate and depth of breathing · breathe into a plastic or paper bag (to raise CO₂ as fast as possible) · talk yourself through the procedure aloud to calm down and slow breathing |
| Why unconsciousness | Blood circulation to the brain is slowed down |
| Alkaline blood effect | More oxygen binds to haemoglobin in the lung, so less oxygen is diffused into the cells |
| Also defined as | A normal compensatory physiological reaction to a drop in ppO₂ — e.g. climbing a high mountain |
| Approach scenario | Dizzy + tingling hands + rapid heart rate on a bad-weather approach = hyperventilation → control the rate and depth of breathing |
Hypoxia vs hyperventilation — the comparison question
Cyanosis exists only in hypoxia. Tingling in arms/legs is common to both. Euphoria is hypoxia. The cures are opposite: hypoxia → oxygen and descend; hyperventilation → slow the breathing / paper bag. Never use a mask for hyperventilation, never a paper bag for hypoxia.
| Dry air | 78% nitrogen · 21% oxygen · 0.9% argon · 0.03% CO₂ (precisely: N₂ 78.08%, O₂ 20.94%) |
| Largest part | Nitrogen — including below 70 000 ft |
| Oxygen percentage with altitude | Constant at 21% at every altitude — it is the partial pressure that falls, not the percentage. Same in cabin air as at sea level |
| ICAO Standard Atmosphere data | 1, 2, 3 — density, pressure, temperature. Humidity is NOT included |
| Troposphere lapse rate | −2 °C per 1 000 ft |
| Ozone | A toxic gas, situated in the stratosphere, removed by ozone converters |
| Pressure change with altitude | Non-linear, with a higher rate of change at lower levels. The greatest absolute drop is between 0 and 5 000 ft |
| Half sea-level pressure at | 18 000 ft — where ppO₂ is also halved |
| Cabin humidity | 5–15% (humans need 40–60%) → causes dehydration. Statements 2 and 3 |
| Radiation | Galactic (cosmic) — steady and predictable, increases with altitude — and solar from flares. Risks: cancer and birth defects. Records kept above 49 000 ft |
| Law | States | Explains |
|---|---|---|
| Dalton | Total pressure = sum of the partial pressures | Altitude hypoxia |
| Henry | Gas dissolved in a fluid ∝ pressure of that gas above the fluid | Decompression sickness / evolved gas |
| Boyle | Volume inversely ∝ pressure (the balloon) | Trapped gas expansion — barotrauma. At sea level a gas has ⅓ of the volume it has at 27 000 ft |
| Fick / Graham (diffusion) | Gas moves from high to low concentration | O₂ and CO₂ transfer at the alveoli |
Gases of physiological importance to man: oxygen and carbon dioxide.
| Altitude | Requirement / equivalence |
|---|---|
| Up to 10 000 ft | Air only |
| 10 000 – 33 700 ft | Oxygen/air mixture |
| 33 700 ft | 100% O₂ = breathing air at sea level. Total pressure 190 mmHg → ppO₂ ≈ 38 mmHg |
| 38 000 ft | 100% O₂ = breathing air at 10 000 ft. "100% O₂ lifts the physiological safe altitude to" → 38 000 ft |
| 40 000 ft | 100% O₂ = breathing air at 10 000 ft. "100% O₂ elevates the physiological safe altitude to" → 40 000 ft |
| Above 40 000 ft | 100% oxygen under positive pressure |
38 000 vs 40 000
Both are marked correct on duplicate questions. Match the verb: "lift" → 38 000 ft, "elevate" → 40 000 ft. "Breathing pure O₂ without pressure is sufficient up to…" appears as both 38 000 and 40 000 — take whichever is offered.
Calculation: ppO₂ = 21% (use 20%) × total pressure.
| Cornea + crystalline lens | Cause the convergence of light rays onto the retina. The cornea is the clear portion where light passes through |
| Lens | Performs accommodation — changing shape via the ciliary muscle. Focusing near → the lens becomes more spherical |
| Iris / pupil | The iris controls the size of the pupil; the pupil controls the amount of light striking the retina |
| Retina | Light-sensitive inner lining containing the photoreceptors — acquires the visual signal and codes it into physiological data |
| Fovea | Area of best day vision; cones predominate. Piercing/alphanumeric vision is limited to the foveal area |
| Blind spot | The optic disc — the optic nerve has no rods or cones |
"The fovea is…"
Both "the area of best day vision and NO NIGHT VISION AT ALL" and "…and OF REDUCED VALUE AT NIGHT" are marked correct in different versions. Take whichever appears.
| Rods | Cones | |
|---|---|---|
| Vision | Scotopic — night | Photopic — day and colour |
| Location | Peripheral zone of the retina | Central zone / fovea (~150 000 per mm²) |
| Chemical | Rhodopsin / visual purple — needs Vitamin A | — |
| Hypoxia | More affected — night vision is the most sensitive function | Also highly sensitive (colour vision) |
| Good for | Detecting moving objects (peripheral vision) | Detail, colour, resolution |
Correct statement combination: 1 and 3 — rods on the peripheral zone and cones on the central zone; rods allow night vision. Central vision statements: 2 and 4.
| Dark adaptation time | 30 minutes (25–30 min). Light adaptation: 10 seconds |
| Why more sensitive after 30–45 min | Both: "light bleaches out visual purple (rhodopsin)" and "visual purple must build up in the rods" |
| Night scanning technique | Look to the side (10–15°) of the object — slight eye movements, do not focus directly on it |
| Optimising night vision | 1, 3, 4 — adapt to low illumination · do not focus on the point observed · avoid blinding light sources |
| Degraded by | All four — hypoxia · smoking · poor diet lacking Vitamin A · bright lights. Also age, cabin altitude above 8 000 ft, alcohol |
| Hypoxia affects night vision from | 5 000 ft (≈1 600 m — within the indifferent zone) |
| Vitamin A | Essential to the regeneration of visual purple. Statements: 1 and 3 correct, 2 and 4 false — excess Vitamin A does not improve night vision |
| Myopia | Near-sightedness — image forms in front of the retina |
| Presbyopia | Long-sightedness / far-sightedness linked with age (both wordings marked). Both: a result of normal ageing and the lens hardens. Causes a decrease of accommodation. Common over 50 |
| Astigmatism | Inability to focus different meridians simultaneously — caused by unequal curvature / a misshapen cornea |
| Glaucoma | Increased intraocular pressure; detected by pressure testing the eyeball. Characterised by 2, 3, 4 — progressive narrowing of the visual field · insidious onset · raised pressure. (Light adaptation is not disturbed). Can lead to total blindness |
| Cataract | Clouding of the lens |
| Colour blindness | May be subtle and only detected with specialised tests |
| Visual acuity affected by | Hypoxia, age and angular distance from the fovea. At altitude: all four — anaemia, smoking, CO poisoning, hypoxia |
| Visual disturbances caused by | 1, 2, 4 — hyperventilation, hypoxia, fatigue. (Not hypertension) |
| Eye movement | Short jerky movements called saccades; smooth vision achieved in the visual cortex |
| Why scan despite a 180° field | Only in the foveal area is resolution good enough to see an object clearly |
| Depth perception | Binocular vision at close/medium range; proportion and perspective further away. Stereoscopic vision = focusing both eyes on a single object |
| Colour vision requires | Only 1 — a considerable amount of ambient light |
| Good sunglasses must | Absorb enough visible light to eliminate glare without decreasing visual acuity (long version adds: absorb UV and IR, and absorb all colours equally) |
| Photochromic sunglasses | Disadvantage in the cockpit — they depend on UV light, which is screened by the cockpit glass |
| Warned of a thunderstorm | Turn the cockpit lights up |
| Does NOT impair photosensitive cells | High speed |
| Part | Contains / does |
|---|---|
| Outer ear | Collects sound |
| Middle ear | The ossicles — malleus, incus, stapes (hammer, anvil, stirrup) |
| Inner ear | Cochlea (sound) · semi-circular canals (angular) · otoliths (linear + gravity). Perceives all three: angular acceleration, linear acceleration, noise |
| Eustachian tube | Equalises pressure between the middle ear and the external atmosphere. Passageway between the nasopharynx / throat and the middle ear (both wordings marked). Opened by swallowing |
| Audible range | 20 Hz – 20 kHz — but 16 Hz – 20 kHz is also marked. Prefer 20 Hz–20 kHz when offered. Greatest sensitivity 750 Hz – 3 kHz |
| Sound is measured in | dB (decibels) |
| Noise-Induced Hearing Loss | Governed by intensity and duration of noise in excess of 90 dB. Causes permanent loss of selected frequencies by damaging the sensitive membrane in the cochlea |
| Noise damage depends on | All four — intensity · frequency · exposure time · proper use of the headset |
| How noise damages hearing | Both: hair cells fatigue and need several hours of quiet, and if loud/long enough they may never return to normal |
| Does noise above 90 dB improve performance? | Never |
| Presbycusis | Gradual loss of hearing with age — high tones go first |
| Conductive hearing loss | 1, 3, 4 — ossicle damage · outer-ear obstruction · ruptured tympanic membrane. (Auditory nerve damage is sensorineural, not conductive) |
| Hearing tests at medicals | To detect early signs of deafness |
Definition: caused by pressure differentials between gases in hollow cavities of the body and the ambient pressure — disturbances of pressure equalisation in air-filled cavities. Governed by Boyle's Law. Most frequent locations: facial sinuses, middle ear and dental cavities.
Climb vs descent
Descent is worse for ears and sinuses (the tube collapses shut and cannot be vented). Climb is worse for teeth and the gut (gas expands). Aerodontalgia in the descent = No.
| Otic barotrauma (aerotitis) | Worse on descent — the air in the middle ear is at lower pressure than the cabin, which closes the Eustachian tube so pressure cannot be equalised. Accompanied by reduced hearing and a feeling of increasing pressure |
| Counter-measure | Stop descending, climb again, then descend with a reduced sink rate. Also the Valsalva: close the mouth, pinch the nose, blow out, and swallow or move the lower jaw |
| Aerotitis vs aerosinusitis | Hearing difficulties normally accompany aerotitis |
| Flying with a cold | Tissue at the nasal end of the Eustachian tube swells, so pressure cannot equalise; pain and eardrum damage, particularly during fast descents. Risks: 2, 3, 4 — ear pain on descent, pressure vertigo, sinus pain. May cause incapacitation |
| Gastrointestinal gas | On ascent the gases expand → pressure pain or flatulence. More frequent above 18 000 ft unpressurised. Cure: descend |
| Passenger with an inflated belly at 8 000 ft | 1, 2, 3 — press the stomach in gently / massage · stand up to release gas · eat less gas-forming food and avoid carbonated drinks in future. (Not drink a lot of water) |
| Barotrauma after decompression involves | 1 only — the digestive tract |
| Pre-flight meal | Simple, easily digested, with non-carbonated water |
| Most frequent cause of in-flight incapacitation | Acute gastrointestinal disorders |
| GI or cardio-pulmonary pain before take-off | 2 and 3 — assess your fitness, with a doctor if necessary; if in doubt, do not fly |
| Barodontalgia | Arises with irritations of the sensitive tissues close to the root of a tooth |
An error is the mismatch between the pilot's intention and the result of his actions. Current thinking: humans are fallible and errors are inevitable / inescapable — systems and procedures should be designed to minimise them. To minimise error, first understand its nature. Improvement of reliability entails understanding the causes and finding means of recovery.
| Active error | Latent error | |
|---|---|---|
| Who | Produced by the operator / front-line | Built into the system earlier (design, management) |
| Detection | Rapidly detected via the effects and consequences it induces | Remains undetected; hard to identify due to the time lag between generation and occurrence |
| Where | At the human/system interface, immediate effect | Dormant in the system |
| Statements | 2 and 3 — rapid direct consequences; down to first-line operators | 1, 2, 4 — remain undetected · manifest only under certain conditions · lull pilots into security |
| Example | — | An unnoticed way-point error in the aircraft database |
| Error vs violation | Violations are deliberate; errors are not. Taking off with a 12 kt tailwind against a 10 kt limit is a violation |
| Murphy's Law | If equipment can be operated incorrectly, sooner or later it will be |
| Human error rate, simple repetitive task | 1 in 100 |
| Human error involvement in accidents | ~70% as primary cause; 70–80% cited overall. There is hardly ever a single cause |
| Accident rate | Approximately 1 accident per million airport movements. Most accidents are caused by lack of good judgement |
| Equipment that cut hull losses in the 1980s | GPWS |
| Motor programme errors | Action slip and environmental capture (habituation) |
| Environmental capture | 1 and 2 — a skill executed in the environment where it is frequently exercised, even when inappropriate; and a skill from one type executed in a new type |
| Habit reversion / negative transfer | The fuel lever example — forward-for-ON in the old type, aft-for-ON in the new |
| Highly automated actions produce | 1 and 4 — capture of a poor action sub-programme · an action mode error |
| Rule-based level errors | 2 and 4 — application of a poor rule, and poor application of a good rule |
| Representation errors originate from | 1, 3, 4 — perception errors · incorrect information from the observed world · receipt of a bad piece of information |
| Combating error | 1, 2, 4 — reduce error-prone mechanisms · improve training · improve recovery. Never sanctions |
| Better error detection | 1, 2, 3 — improve the man-machine interface · systems checking situation consistency · cross-over redundant procedures |
| Coping with low error tolerance | Constantly complying with cross-over verification (cross-monitoring) |
| Error-tolerant system | One where the consequences of an error will not seriously jeopardise safety. A system where one error affects the whole is vulnerable |
| Error chain | Ambiguity · distractions · confusion · no-one flying · no-one looking outside · fatigue · non-standard procedures · violating minima · unresolved discrepancies · departure from SOP · incomplete communications |
| Random error example | Rifle shots scattered high and low around the target |
| Mode error | Associated with automation |
| Organisational error factors | 2 and 3 — fuel-saving policies and rostering |
| Ergonomic factors | Cockpit noise and restricted field of view from windscreen design |
| Age and performance | Little impact when the pilot compensates with flight experience |
| Element | Means | Mismatch example |
|---|---|---|
| Software | Checklists, procedures, manuals, SOPs, symbology, computer programmes | Irrational indexing in an ops manual · conceptual deficiencies in warning systems → L–S |
| Hardware | Aircraft, equipment, tools, buildings | Misreading the old three-point altimeter · poorly designed switches and displays → L–H |
| Environment | The situation the others must function in — social, economic, natural | Disturbance of the biological rhythm → L–E |
| Liveware (central) | The human — the hub of the model; all other components must be adapted and matched to it | — |
| Liveware (peripheral) | Other people — crew, ATC, engineers, management | The interface between people → L–L |
Ergonomics is associated with the human/workplace interface. Detectability of a system = 2 and 4 (automatic monitoring/detection/warning + alerting capability of the interface).
| Decision making is | A voluntary and conscious process of selection from among possible solutions. It results in a choice between different options/solutions to achieve a goal |
| Judgement is | A process involving the pilot's attitude to take and evaluate risks by assessing the situation and deciding on the basis of knowledge, skill and experience |
| A good decision depends on | Analysis of the situation |
| Selection of a solution depends on | All four — objective and subjective criteria · the objective · the risks · the personality of the decision-maker |
| Risk assessment is based on | Subjective perception and evaluation of situational factors |
| Decisions in a cockpit | Remain valid for a limited time only |
| To make sound decisions | Understand why and how we make decisions |
| Facing a problem in flight | Take as much time as you need and is available |
| Emergency decision making requires firstly | Delegation/distribution of tasks and crew co-ordination |
| Rushed decision overlooks | Analysis of the current actual situation, applying instead a decision prepared beforehand |
| After an important decision | Always make time to explain the reasons, even after landing |
| Crew decision making is most efficient if all | Adapt their management style to meet the situational demands |
| Personality trait that helps most | Assertiveness |
| Does NOT improve decision making | The ability to persuade others to follow their own point of view |
| Passenger offers money to press on | Decide to divert if you think it is necessary |
| Confirmation bias | A tendency to look for information which confirms the validity of the decision, and to ignore information indicating the decision is poor. Once a mental model is built we give undue weight to information that confirms it. Best countered by searching for information that will falsify the hypothesis |
| Frequency / habit bias | Tendency to select the most familiar solution first, sometimes to the detriment of the best result. Example: the pilot who orders fuel before flight preparation because he "always flies this route" |
| Which biases apply? | 1, 2, 3 — personal experience alters risk perception · natural tendency to confirm · the group influences the decision. (People do not naturally select only objective facts) |
| Influences on decisions | 1 and 3 — people conform to the majority opinion in their group; people select data meeting their expectations |
| Order and attention effects | All three — the first information determines how later information is evaluated · contradictory information may not get the attention it needs · stress limits attention and reduces flow to the central decision maker |
| Wanting to fit in / be liked | Leads to agreeing with decisions made by other crew members |
| Once thinking a certain way | Difficult to get out of that way of thinking and try a different interpretation |
| An excessive need for safety | Hampers severely the way of pilot decision making |
| Pre-determined opinion | A plan or opinion made before the flight is conducted |
| Personality | The unique organisation of characteristics determining typical behaviour; refers to unique psychological characteristics. Based on heredity, upbringing, childhood environment and experience. In a healthy person, traits are stable — personality is very hard to change |
| Attitudes | Tendencies to respond to people, institutions or events either positively or negatively — or "to respond to people, things or events in a particular manner". Both marked. They are learned dispositions (likes and dislikes) and are the product of personal disposition and past experience |
| Behaviour | The outward result of personality and attitude — and is adaptable |
| Self-concept | How you see yourself. Long form takes both: "a mental blueprint composed of ideas, attitudes, values and commitments influenced by past experience" and "part of our personality formed by the way others reacted to us in our formative years". A co-pilot upgrading to captain will have a changing self-concept because of new roles and tasks |
| Human behaviour is determined by | Biological characteristics, social environment and cultural influences |
| Effectiveness of the individual | The ability to balance the dictates of one's needs and the demands of reality |
| The five hazardous attitudes | Anti-authority · Impulsiveness · Invulnerability · Resignation · Macho |
| "It will not happen to me" | Invulnerability |
| Always proving they are better than anyone | Macho |
| Two basic behavioural styles | Relationship oriented and task oriented |
| Task-oriented behaviour | Both: first consideration to the task or goal, and high task / low relationship = an aggressive style |
| Relationship-oriented | First consideration is the feelings of others |
| Assertive behaviour | Helps you get what you want and need |
| Under-confident co-pilot promoted to captain | Often becomes aggressive if challenged by another crew member |
| Stereotypes | Preconceptions that make us mis-judge individuals even if we have contact with them |
| Peer pressure | Self-imposed pressure from trying to live up to others' performance or expectations |
| Reversion to earlier behaviour | 1 and 3 — when concentration is relaxed, and under stress |
| Effect on attention | Increases the mobilisation of energy and thus facilitates the quality of alertness and attention |
| Excessive motivation | Combined with high stress, limits attention management capabilities; leads to stress which adversely affects performance |
| High motivation relates to | High levels of arousal |
| Primary sources | All four — being in control of one's situation · fear of punishment · success/achievement · social promotion and money |
| High performers | Enjoy their work situation; to perform well one must be motivated by feeling trusted and involved |
| Needs | Lead to a change in motivation and consequently an adaptation of behaviour |
| Maslow's hierarchy | Lowest level = physiological needs. Includes all: freedom from pain and danger · expression of capacities and talents · self-esteem · self-fulfilment · physiological |
| Phobic or obsessional disorders | May require successful treatment before flying is permitted |
| A proficient pilot | Has automated a large part of routine operations to free cognitive resources |
| An experienced pilot | Prepares thoroughly and anticipates the majority of possible problems. Inexperienced pilots refer to information more than experts on the same task |
| Machines are better at | Humans are better at |
|---|---|
| 1, 2, 3 — waiting for an infrequent phenomenon · long-term control of a set value · monitoring that values are not exceeded | 1 and 4 — qualitative decision-making · detecting unusual conditions (smell, noise). Plus creativity, innovation, adaptability and the aptitude to deal with novel situations |
| Automation complacency | Monitoring and cross-checking is reduced because of belief in the infallibility of the automatic systems. Also: boredom and complacency because portions of flight are so completely automated that pilots are lulled into inattention |
| Complacency (general) | Careless negligence or unjustified self-confidence. Definition takes both: "not paying attention and not using the senses properly" and "a state of mind that can occur during routine operations" |
| Passive monitoring | A pilot watching what is going on rather than analysing and constantly checking |
| How to avoid complacency | Regard the automatic system as an additional crew member that must be cross-checked |
| Mode awareness | Being aware of the active mode(s) and understanding the corresponding actions and responses |
| Role of automation | Used as an aid to the pilot, not as an end in itself |
| Advantages | Reduced workload, more time to monitor systems, better situational awareness when managed properly |
| Disadvantages | All of the above. As statements: 1 and 2 — reduced manual competence · increased likelihood of slips while programming. High automation → attention reduced → crew "out of the loop"; also causes routine errors (slips) |
| "Which statement about automation is correct?" | All of the above are correct |
| Glass cockpit technology has | Facilitated feedback from the machine via more concise data for flight-deck communication |
| To avoid wrong decisions, a system should at least | Report its malfunction |
| Man vs computer | Man has more effective means of action (output) and is above all capable of considerable synergy; the human system is more efficient because of its flexibility |
| Design priority against error | Reduce the risks of the appearance or non-detection of errors with serious consequences |
| Axis | Direction | Effect |
|---|---|---|
| Gz — radial | Vertical axis, head to foot | The most significant physiological effect. +Gz pools blood in the lower body → greyout, blackout |
| Gx — linear | Chest to back | 2 and 4 — slight physiological consequences · causes sensory illusions on the pitch axis |
| Gy — transverse | Shoulder to shoulder | 3 only — rare during routine flights |
| Order of +Gz symptoms | Grey-out → tunnel vision → black-out → unconsciousness |
| Grey-out threshold | +3 Gz — the first effect noticed on gradual exposure |
| Tunnel vision threshold | +3.5 Gz |
| Objective +Gz effects | 2, 3, 4 — blood pools in the lower body · BP drops above heart level · soft organs displaced downward. Heart rate increases, it does not decrease |
| Increase G tolerance by | Tightening the stomach muscles — long version: tightening muscles, ducking the head and a kind of pressure breathing. Also bending forward or a supine position, and a tilt-back seat |
| Reduce G tolerance | Obesity, alcohol, sleep deprivation; also low blood sugar and hypoxia |
| Effects depend on | All four — duration · onset rate · magnitude · direction |
| "Long duration" acceleration | Lasting more than 1 second |
| Spinning an aircraft | Angular acceleration predominates |
| Inertia head → feet | Blood pressure in the brain decreases |
| Legal limit, flight and cabin crew | 20 mg per 100 ml of blood |
| Elimination rate | ~0.015% per hour (0.01–0.015 mg% /h) — cannot be expedited; it is purely a question of time. 60 mg/100 ml takes about 4 hours |
| Absorbed | Directly from the stomach and intestines into the bloodstream. Metabolised by the liver |
| Effects | Creates histotoxic hypoxia, increases physiological altitude (1 oz ≈ 2 000 ft). Makes brain cells more susceptible to hypoxia. Judgement and decision making are affected even by small amounts, and normal cautionary attitudes may be lost |
| Loss of fine co-ordination above | 0.05% blood alcohol |
| Alcohol and sleep | Degrades paradoxical (REM) sleep |
| Alcohol with drugs | Intensifies the effects of the drugs |
| Addictive substance | Nicotine |
| Carcinogen | Tar |
| The flight hazard | Carbon monoxide — mild CO poisoning, decreasing tolerance to hypoxia and raising physiological altitude |
| One pack a day costs | 5–8% of total oxygen transport capacity (the explanation text says ~10%, but 5–8% is the marked option) |
| 3 cigarettes in 1 hour at sea level | Lower degree of hypoxic tolerance |
| Moderate/heavy smoker at 10 000 ft | Blood oxygen equal to an altitude above 10 000 ft |
| Smoker risks | All three — coronary heart disease · raised physiological altitude · lung cancer |
| Why dangerous | All of them — initial symptoms not alarming · colourless · odourless · highly toxic · effects are cumulative |
| Mechanism | Competes with oxygen for haemoglobin and binds before O₂ does — affinity 210–250× that of oxygen |
| Symptoms | Headache, increasing nausea, dizziness; as a list 1, 2, 3, 5 — loss of muscular power, headache, impaired judgement, loss of consciousness. Not pain in the joints |
| Source in aircraft | More likely where cabin heating passes air over the exhaust manifold; also cigarette smoke and all engine exhaust |
| Treatment | Increase the oxygen physically dissolved in the blood — i.e. breathe 100% oxygen. Recovery takes several days |
| Effects with altitude | Increase as altitude increases; reduce TUC and cause hypoxia at a lower altitude than normal |
| Antihistamines | Cause drowsiness and dizziness — in the "which apply" version the answer is only 1. In the long list: all five (drowsiness/dizziness, dry mouth, headaches, impaired depth perception, nausea) |
| Aspirin, excessive | Gastric bleeding |
| Over-the-counter medicines | Get professional advice from an aviation medical specialist before flying while self-medicating |
| Why medicines affect fitness to fly | All four — the disease itself may disqualify · flight conditions modify the body's reactions · side effects impair safety · effects do not necessarily disappear when treatment stops |
| Sleep/nerve medication | Watch the effect on reaction time and perceptual awareness |
| Circadian cycle | 25 hours free-running — but 24 hours is also marked. If the question says "free-running" or "about", take 25 h |
| Sleep needed per night | 8 hours |
| Sleep cycle length | 90 minutes — 5 stages including REM |
| Resynchronisation rate | 1 – 1.5 hours per day |
| Direction of travel | Eastbound is worse — takes longer to resynchronise. Westbound readjustment is most rapid. Varies substantially between individuals (statements 2 and 4) |
| Stopover more than 24 h | Move to the new local time as soon as possible. (Note: one question on crossing 3–4 time zones with a >24 h layover marks 2 and 3 — keep departure rhythm and maintain regular living patterns) |
| Stopover less than 24 h | Maintain eating and sleeping cycles on home time |
| Layover day 3 in Moscow | Relevant measure is LT — local time |
| Orthodox / deep sleep | Physical recovery and reconstitution of neuron energy reserves |
| Paradoxical / REM sleep | Rapid eye movements. More important for the regeneration of mental functions than other stages. Each succeeding cycle contains more REM; frequent interruption is harmful |
| Sleep pattern is associated with | Body temperature. Duration of a sleep period is governed by the point in your circadian rhythm at which you try to sleep |
| During sleep | 1, 2, 3 — metabolic rate falls · arterial BP falls · pulse decreases. Sensitivity of the senses decreases |
| Lack of sleep causes | Increased fatigue, reduced concentration, increased risk of sensory illusions (+ mood disorders in the long version) |
| Sleep-deprivation effects | 1 and 3 — increase with altitude and with higher workload |
| Sleep loss awareness | Both correct — a person is unlikely to be aware of their own performance degradation, and performance loss lasts up to 20 minutes after a nap (sleep inertia) |
| Biological clock disturbed by | 2 and 4 — day flight Amsterdam–New York, and night flight New York–Amsterdam |
| BMI | kg / m². Obese over 30 for males, 29 for females. (1.7 m, 57 kg → BMI ≈ 19.7 → normal) |
| Exercise for coronary health | Double the resting heart rate, at least 20 minutes, three times a week |
| Weight loss | Exercise is beneficial, but the most efficient way to lose weight is reducing caloric consumption |
| Breakfast | About 25% of daily calorie intake |
| Caffeine excess | Over 250 mg/day |
| Trace elements | Obtained through a balanced diet |
| Dehydration | Thirst is a belated symptom; causes dizziness and fatigue. Drink non-carbonated liquids before you get thirsty (statements 2 and 3) |
| Hypoglycaemia | Caused by not eating regularly or fasting. Symptoms: headache and lack of concentration. Prevention: eat regularly, balanced diet |
| Heart attack (myocardial infarction) | Total blockage of a coronary artery leading to death of a piece of heart muscle; the most common cause of death in men over 40 |
| Predisposing factors | Smoking, high cholesterol, diet, blood pressure — plus obesity, distress, family history (all four) |
| Angina | A symptom of reduced oxygen supply to the heart muscle from narrowing/obstruction of a coronary artery |
| Stroke | Blood supply to part of the brain is cut off |
| Hypertension | Increased pressure on the arterial walls; increases the risk of heart attack and stroke |
| Obesity is associated with | High blood pressure, coronary problems, diabetes |
| Medical disqualification factors | High and low blood pressure and poor circulatory condition |
| Body core below 37 °C | Reasoning problems begin |
| Body core below 35 °C | Shivering ceases, followed by apathy. Hypothermia disorders appear |
| Body core at 39 °C | Impairment of physical and mental performance |
| Danger of extreme cold | Sleepiness with a feeling of contentment or apathy. Earliest significant feature: apathy |
| Response to cold | Intense vasoconstriction. Hypothermia increases the demand for oxygen (initially) |
| Response to heat | 3 and 4 — sweating and vasodilation of peripheral vessels |
| Hypothermia statements | 1, 3, 4 — affects physical and mental ability · shivering combats cold but uses a lot of energy · disorders below 35 °C. Man has NO effective natural protection against intense cold |
| Heat acclimatisation | Complete adaptation to a hot country takes about a fortnight. Exercise in tropical heat causes painful muscle and abdominal cramps |
| Avoid in developing/tropical areas | All five — ice cubes · swimming in lakes/rivers · unpeeled fruit · local ice cream and salads · short clothing in the evening |
| Contaminated water causes | Typhoid, Cholera, Dysentery — and Hepatitis A (food or water) |
| Hepatitis B / C | Tattooing and immunisation with improperly sterilised needles |
| Yellow fever | A virus transmitted by an infected mosquito |
| Tetanus | Bacterial spores via a puncture in the skin |
| Cold drinks in the tropics | Take from sealed containers; avoid ice |
| Ditching | Ditch PARALLEL to the swell — "ditch against the swell" is the not advisable option |
| Fire in flight — most fatalities | Suffocation from fumes from aircraft furnishings and wiring |
| Fuel spillage on the body | Wash with copious water and WITHOUT soap |
| After a hospital stay | Seek advice of the authority or AME |
| Medical fitness requirements are in | Part 67 |
| Regular exercise | 1 and 2 — raises pulse/stroke volume short term, lowers BP/HR long term. It does NOT reduce hypoxia tolerance |
| Scuba, medicines, fluids, diet | 2 and 3 — many medicines are incompatible with flight safety; drink adequate fluid |
| The 5 human senses | Tend to adapt — true |
These are the places where two versions of the same question carry different marked answers, or where the marked answer is factually wrong. Reading this section is worth more marks per minute than anything else here.
True contradictions — you cannot get both right
1. "Hypoxia can occur because:"
Marked "you are hyperventilating" in Incapacitation, and "the percentage of oxygen is lower at altitude" in Extra Questions. The percentage is 21% at every altitude, so that option is factually false. Answer "you are hyperventilating" and appeal if marked wrong.
2. Hollnagel's descriptive error model (repetition/omission · forward and backward leap · intrusion and anticipation · intrusion)
Marked "1, 2, 4" in Human Error, "1, 2, 3" in Extra Questions. "1, 2, 4" is better supported — take it if both appear.
Marked answer is wrong — answer correctly and appeal
Number pairs — take whichever is offered
| Item | The two answers | How to choose |
|---|---|---|
| Circadian cycle | 25 h / 24 h | "Free-running" or "about" → 25 h |
| Critical threshold, no O₂ | 20 000 / 21 000 ft | Both marked — take what appears |
| Pure O₂ without pressure sufficient to | 38 000 / 40 000 ft | Both marked |
| 100% O₂ raises safe altitude to | 38 000 / 40 000 ft | "Lift" → 38 000 · "elevate" → 40 000 |
| Audible range | 20 Hz / 16 Hz – 20 kHz | Prefer 20 Hz–20 kHz |
| Short-term memory affected from | 8 000 / 12 000 ft | "Can already be affected as low as" → 8 000. "Hypoxic hypoxia, STM impairment starts at" → 12 000 |
| Metabolic waste product | Water / carbon dioxide | Both marked |
| Listening / speaking rate | 900 / 125 wpm | Choose 900 and 125 |
| 20 cigarettes/day O₂ loss | 5–8% | Explanation says ~10%, the marked option is 5–8% |
Near-identical stems where one word decides the answer
| "The fovea is…" | "no night vision at all" or "of reduced value at night" — both marked |
| "Presbyopia is…" | "long sightedness" and "far sightedness" linked with age — both marked |
| Eustachian tube joins… | "nasopharynx and the middle ear" or "throat and the middle ear" |
| Vestibular apparatus consists of… | "canals and the otoliths" or "canals, utricles and saccules" |
| Pilot's vertigo… | "contradictory impulses to the CNS" or "rotation due to multiple irritation of several canals" |
| The Leans caused by… | "prolonging a turn" or "reducing bank following a prolonged turn" |
| Co-action recommends… | "working in parallel toward one common objective" or the synergy definition |
| Increased CO₂ leads to… | "shortness of breath" or "an increased respiratory rate" |
| Hyperventilation is… | "an increased lung ventilation" or "a normal compensatory reaction to a drop in ppO₂" |
| Above 10 000 ft hypoxia because… | "ppO₂ below the critical value of 55 mmHg" or "ppO₂ lower than at sea level" |
| Most dangerous hypoxia symptom | "impaired judgement" or "impaired judgement, disabling the pilot to recognise the symptoms" |
| Increase Gz tolerance… | "tightening the stomach muscles" or the long "muscles + ducking the head + pressure breathing" |
| DCS symptoms… | "bends, chokes, skin, neurological, circulatory shock" or "can appear with a delay after landing" |
| Metabolism is… | "transformation by which energy is made available" or "generation and utilisation of energy by cells and tissues" |
| Motion sickness systems | 2, 3, 4, 5 (incl. gastro-intestinal) or 2, 3, 4 — hearing is never included |
| Disorientation more likely when… | 1, 2 + "approaching over still water at night" or 1, 2 + "having a cold" |
| Night-flying illusion, you should… | "rely on instruments" or "continue on instruments" |
| Active error is… | "produced by the operator and rapidly detected" or the long "…via the effects and consequences it induces" |
| Divided attention is… | "alternative management of several matters" or "several matters dealt with individually one after the other" |
| Self-centred captain result | co-pilot "disengaging, delayed responses or aggression" or "…or demonstrate the scapegoat effect" |
| Anderson's three stages | cognitive, associative, automatic or cognitive, associative, autonomous |
| Sunglasses requirement | short version (glare without reducing acuity) or long version (+ UV/IR + all colours equally) |
| Heart attack is… | "total blockage of a coronary artery" or "most common cause of death in men over 40" |
"Which of the following statements is correct?" — a bare stem
Several questions have no usable stem. Read the options. The answer has been: 70% of information enters via the visual channel · scotopic vision is via the rods · short-term memory is affected by interruptions · oxygen diffusion from blood to cells depends on the ppO₂ gradient · problems in personal relationships hamper communication · high performers enjoy their work situation — depending on which set of options appears.
One more that catches people
"Which system should be trusted during flight in IMC?" — the answer is VISUAL. It means your eyes reading the instruments, not looking outside. The wrong options are vestibular, proprioceptive and "combined".
When two individually true statements appear plus a combined option, and you can verify two of them, take the combined option. Confirmed cases:
| "1, 2, 3, 4 — which combination?" | Evaluate each statement independently, then find the option. Look for the single obviously false statement — it usually eliminates two options at once |
| "Which is NOT…" | Read twice. The correct answer is the false statement |
| "Which lists ALL the correct answers?" | Usually the longest list containing no false statement |
| Two statements only | Both true / both false / one of each — four options map exactly onto those |
| Calculations | ppO₂ = 21% × total pressure · BMI = kg/m² · alcohol clears 0.015%/h · cardiac output = HR × stroke volume |
If you remember nothing else from this page, remember these.
| 01 | Instruments — the answer to every disorientation, illusion and vertigo question. |
| 02 | Own oxygen mask first — the answer to every decompression question. |
| 03 | Impaired judgement — the most dangerous hypoxia symptom. |
| 04 | Cyanosis = hypoxia only. Tingling = both. Euphoria = hypoxia. |
| 05 | Slow the breathing / paper bag — hyperventilation. |
| 06 | Narrow → feel high → fly low → land short. Wide is the opposite. Upslope like narrow, downslope like wide. |
| 07 | Henry = DCS · Dalton = hypoxia · Boyle = trapped gas · Fick/Graham = diffusion. |
| 08 | Descent is worse for ears and sinuses; climb is worse for teeth and gut. |
| 09 | Subjective evaluation — the answer to nearly every "what determines stress?" question. |
| 10 | Rods = night, periphery, rhodopsin. Cones = day, fovea, colour. |
| 11 | Semi-circular canals = angular. Otoliths = linear and gravity. |
| 12 | The lists: acute/chronic fatigue · alarm/resistance/exhaustion GAS · cognitive/associative/automatic Anderson · skill/rule/knowledge Rasmussen · monitor/evaluate/anticipate SA · software/hardware/environment/liveware×2 SHELL. |
Compiled from the 1 417-question SACAA CPL bank across 13 topics, the 040-series JAA syllabus question set, and the master notes. Where the bank marks an answer that is factually wrong, both are given — answer what is marked, then appeal. Good luck.