Human Performance and Limitations

Why does a pilot need to study human factors?

Why it matters

Four branches: why, where from, what flight does to you, and the numbers. Tap + to open.

• Human factors why pilots study it Human performance and limitations: the human factor knowledge ICAO requires of flight crew, also useful to cabin crew, ATCs and maintenance personnel.
  • Why it matters Humans are the most flexible yet most vulnerable part of the aviation system, and three out of four accidents came from less than optimum human performance.
    • Humans: most flexible, most vulnerable People are the most flexible and adaptable part of aviation, and the most valuable, but also the part most easily knocked off their best by outside pressures.
    • 3 in 4 accidents: human performance Less than optimum human performance.
    • Error is generally inescapable It is inherent to how the mind works, so systems must tolerate it.
    • Flight and cabin crew, ATC, maintenance The material is written for flight crew to meet ICAO requirements; the relevant parts also serve cabin crew, ATCs and maintenance personnel.
  • Where the knowledge comes from Human factors is multidisciplinary, drawing on psychology, engineering, physiology, sociology, anthropometry and more, while staying focused on practical problems.
    • Six core sciences psychology to anthropometry Psychology, engineering, human physiology, medicine, sociology and anthropometry, the six disciplines set out in the book's table.
    • Problem-oriented, not one discipline Human factors is practical and problem-oriented rather than discipline-centred.
  • What flight does to the body Flight makes numerous, large demands on the body's compensatory mechanisms: pressure, temperature and motion changes, and reduced oxygen.
    • Pressure, temperature, 3D motion three changes to adapt to The changes in flight that matter most to the body: big swings in air pressure, large changes in temperature, and fast movement up, down and sideways.
    • No oxygen: death in 5 to 8 min The body can cope with less oxygen for a while, but with no oxygen at all a person dies in about five to eight minutes.
  • What the numbers say Roughly one accident for every million airport movements; human factors named in more than 73% of accidents; and CFIT the most common kind.
    • Over 73% human factors Human factors are named as a main cause in more than 73% of accidents, and that share has hardly moved since the 1950s.
    • About 1 per million movements Leaving out sabotage and terrorism, commercial aviation has roughly 1 accident for every million airport movements.
    • CFIT: most common accident Flying a working aircraft into the ground (CFIT) is the most common kind of air accident.

Takeaway: The human is the most flexible part of the system and the most vulnerable, and error is part of how the mind works.

Which sciences, which phases, which numbers?

Human factors in numbers

Three views: the six sciences, accidents by phase and the headline numbers.

Human factors studies people at work in aviation: the most flexible part of the system, and the most vulnerable.

• Human factors studies people at work in aviation: the most flexible part of the system, and the most vulnerable.
• Sciences
• Six sciences, six questions
• Human factors draws on many sciences; these are the six core ones. Spin to find them all.
• Psychology
• 1
• Mind and behaviour
• Studies mind and behaviour. Used for displays, training, selection, stress.
• Engineering
• 2
• Matter and energy put to use
• Studies matter and energy put to use. Used for controls, systems, simulators.
• Human physiology
• 3
• The healthy working body
• Studies the healthy working body. Used for environment, heat, cold, hypoxia.
• Medicine
• 4
• Disease and injury
• Studies disease and injury. Used for toxic smoke, impact protection, health.
• Sociology
• 5
• Groups and teams
• Studies groups and teams. Used for crew selection, passenger safety.
• Anthropometry
• 6
• Body sizes and muscle strength
• Anthropometry studies human body sizes and muscle strength, applied to work station layout, seat adjustment and reach, and maintenance access door size.
• Phases
• When do accidents happen?
• Accidents bunch up at the start and the end of a flight. The taller the bar, the bigger its share of accidents. Drag the slider or tap a bar.
• Most accidents
• Fewest
• Landing
• 24.1% of accidents
• Landing alone accounts for 24.1% of accidents, more than any other phase of flight.
• Takeoff and initial climb
• 23.4%, in about 2% of the time
• 23.4% of accidents occur during takeoff and initial climb, in about 2% of flight time.
• Cruise
• 15.7%, in 83% of the time
• Cruise fills 83% of flight time but accounts for only 15.7% of accidents.
• Approach
• 9.7%; with landing 33.8%
• Approach (9.7%) and landing (24.1%) together give 33.8% of accidents, so approach and landing is where most accidents take place.
• Odds
• The numbers behind human factors
• Headline figures from the chapter. Tap a row.
• Over 73%
• Accidents citing human factors
• Human factors are named as a main cause in more than 73% of accidents, and that share has hardly moved since the 1950s. Do not mix this up with the accident rate.
• 73%
• Three in four
• Less than optimum human performance
• Year after year, three accidents in every four come from people not performing at their best, usually called human error.
• 3 IN 4
• About 1 per million
• Accidents per airport movement
• Commercial aviation, excluding sabotage and terrorism.
• 1 IN 1000000
• 57.2% at the ends
• Takeoff, approach and landing
• Takeoff and initial climb plus approach and landing account for 57.2% of accidents, in under 17% of flight time.
• 57.2%
• Five to eight minutes
• With no oxygen at all
• The body can cope with less oxygen for a while, but with no oxygen at all a person dies in about five to eight minutes.
• 5-8 MIN

Takeaway: Six sciences: psychology, engineering, physiology, medicine, sociology, anthropometry. Most accidents at landing and takeoff. Human factors in over 73%.

What does each science give human factors?

What each science gives

Each science answers one kind of question. Tap + to open each.

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Core HF discipline or another contributor?

Named disciplines

Tap a science, then where the book lists it.

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Which science would study this problem?

Which science

Read each case and press the stamp that applies.

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What makes a professional pilot?

Pilot qualities

The book lists 18 qualities. Here they sit in four groups. Tap + to open each.

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In which phase of flight do accidents happen?

Flight phases

Bars show each phase's share of accidents. The strip below shows its share of flight time.

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How does the body cope when oxygen falls?

Less oxygen

Fly the route: three ways the body compensates, then the hard limit.

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What does flight demand of the body?

How the body adapts

Three big changes, four everyday adjustments, one hard limit. Tap + to open each.

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Numbers to know

Numbers

The figures examiners like, in one list.

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Pairs that catch students out

Don't mix up

Read each pair, then the rule that tells them apart.

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Test yourself

Ten questions from this chapter.

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