CPL Human Factors practice exam.

Methods of detecting error in the aviation system include:

1. AAnnual renewal of the medical certificate, during which the examiner reviews the errors the pilot has made in the past year
2. BWaiting for accidents to occur and then investigating them thoroughly to establish what errors were made by the crew
3. CRandom drug and alcohol testing of flight crew, which is the primary method used to detect error in the aviation system
4. DCrew monitoring and cross-checking, standard calls and read-backs, alerting systems, flight data monitoring, LOSA and occurrence reporting

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Crew monitoring and cross-checking, standard calls and read-backs, alerting systems, flight data monitoring, LOSA and occurrence reporting

Errors are detected in real time by the crew (the pilot monitoring's primary job), by ATC (read-back errors, altitude deviations) and by aircraft systems (configuration warnings, EGPWS, TCAS, altitude alerts); after the event they are detected by flight data monitoring programmes, LOSA observations, incident reports under Part 12, internal hazard reports and audits. Each detection channel feeds the SMS so that patterns are found before they produce an accident. Reference: syllabus 34.52.14; ICAO Doc 9683; ICAO Doc 9859; CAR Part 12.

Positive G (+Gz) acceleration affects the body by:

1. APooling blood in the lower body and starving the head, producing grey-out, tunnel vision and black-out and ultimately G-induced loss of consciousness
2. BForcing blood into the head and producing a red haze over the vision, together with a severe headache and facial congestion
3. CHaving no measurable effect on a healthy pilot below about 9 G, which is why civil aerobatic aircraft carry no G limits for the pilot
4. DImproving vision by increasing blood flow to the eyes, which is why aerobatic pilots report unusually sharp vision under load

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Pooling blood in the lower body and starving the head, producing grey-out, tunnel vision and black-out and ultimately G-induced loss of consciousness

Under sustained +Gz (head to foot) the heart cannot maintain arterial pressure at eye and brain level: at about 3.5-4.5 G peripheral vision greys out and narrows, then vision is lost (black-out) while the pilot remains conscious, and at higher or more rapidly applied G (around 5 G and above for an unprotected, relaxed pilot) consciousness is lost (G-LOC) with a period of confusion on recovery. Tolerance is reduced by fatigue, dehydration, hypoxia, alcohol, illness and heat, and improved by the anti-G straining manoeuvre and G-suits. Reference: syllabus 34.24.2 and 34.24.4; ICAO Doc 8984; FAA PHAK.

The circulatory system consists of:

1. AThe lungs and airways through which oxygen is carried in the air stream to the tissues and carbon dioxide is carried back out again
2. BThe lymph glands and spleen, which filter the blood and remove excess oxygen so that the tissues are not damaged by over-oxygenation
3. CThe heart as a double pump, arteries carrying blood away from it, capillaries where exchange occurs, and veins returning blood to it
4. DThe kidneys and bladder, which regulate blood pressure and control the oxygen content of the blood by adjusting the volume of urine

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The heart as a double pump, arteries carrying blood away from it, capillaries where exchange occurs, and veins returning blood to it

The heart's right side pumps de-oxygenated blood to the lungs (pulmonary circulation) and the left side pumps oxygenated blood to the body (systemic circulation). Arteries carry blood away from the heart under pressure, capillaries allow oxygen, nutrients and waste to exchange with the tissues, and veins return blood at low pressure, assisted by valves and muscle action. Blood pressure, heart rate and the distribution of blood are all affected by G forces, stress, dehydration and illness. Reference: syllabus 34.8.6 and 34.8.8; ICAO Doc 8984.

Stress in oneself or a colleague can be identified by:

1. APhysical signs (tension, headaches, poor sleep), mood change (irritability, anxiety), poor concentration and indecision, and behaviour change
2. BThe person's total flying hours for the month, because stress is directly proportional to the number of hours flown
3. CA blood test that measures the level of the stress hormone cortisol, which is the only reliable way to identify stress in a pilot
4. DOnly by the person concerned, because stress is an internal state that is never visible to colleagues, family or supervisors

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Physical signs (tension, headaches, poor sleep), mood change (irritability, anxiety), poor concentration and indecision, and behaviour change

Stress shows in the body (muscle tension, headache, indigestion, palpitations, disturbed sleep, tiredness), in mood (anxiety, irritability, depression, loss of humour), in thinking (narrowed attention, poor memory, indecision, rigid thinking) and in behaviour (withdrawal, aggression, taking shortcuts, more errors, increased alcohol, smoking, caffeine or eating). Colleagues often notice the change before the person does, which is one value of a good crew and reporting culture. Reference: syllabus 34.38.10; ICAO Doc 9683.