Free UK CAA Part-66 Module 9A Human Factors (B1.1 MCQ) Practice Questions

Sample Practice Questions

Try these 10 sample questions from the UK CAA Part-66 Module 9A Human Factors (B1.1 MCQ) practice bank. Each includes the answer and explanation. Continue with the interactive practice above to review the full question set.

1. 1What is the central aim of human factors in aircraft maintenance?

   1. A.To optimise the relationship between personnel and systemsCorrect answer: A
   2. B.To transfer responsibility for safe maintenance to equipment
   3. C.To increase task speed by reducing the use of procedures
   4. D.To select personnel who can work without human limitations

   Explanation: CAP 715 states: "The aim of human factors is to optimise the relationship between maintenance personnel and systems with a view to improving safety, efficiency and well-being" The aim concerns how people and systems work together, with safety, efficiency and well-being as goals. It does not remove human limitations or justify bypassing procedures.

   Reference: CAA CAP 715: Aircraft Maintenance Engineering Human Factors — Chapter 1, 1.4.3, page 2

2. 2Which retinal receptors are principally responsible for fine detail and colour discrimination in good light?

   1. A.Rods concentrated toward the retinal periphery
   2. B.Cones concentrated in the central retinal areaCorrect answer: B
   3. C.The nerve fibres leaving the eye at the blind spot
   4. D.The muscle fibres that change the pupil diameter

   Explanation: CAP 715 states: "Cones function in good light and are capable of detecting fine detail and are colour sensitive." Cones support colour and fine-detail vision. Rods favour low-light and peripheral movement detection; the optic nerve and iris muscles do not perform the cones' receptor function.

   Reference: CAA CAP 715: Aircraft Maintenance Engineering Human Factors — Chapter 2, 2.5.1, page 3

3. 3What is diffusion of responsibility within a maintenance team?

   1. A.Team members disagree about the most effective technical method
   2. B.A team adopts a riskier decision than its members would individually
   3. C.A person increases effort because colleagues can observe the result
   4. D.Individuals assume someone else will act, so no one takes responsibilityCorrect answer: D

   Explanation: CAP 715 states: "no-one feels personally responsible for safety (referred to as diffusion of responsibility)." Responsibility becomes so dispersed that individuals expect others to act. Technical disagreement, risky shift and increased individual effort describe different phenomena.

   Reference: CAA CAP 715: Aircraft Maintenance Engineering Human Factors — Chapter 3, 2.5.2, page 3

4. 4Why can a minor illness matter when assessing fitness for maintenance work?

   1. A.Illness can affect cognitive as well as physical task performanceCorrect answer: A
   2. B.Illness affects performance only when it limits limb movement
   3. C.Illness changes the task requirements rather than the person's capacity
   4. D.Illness is relevant only if it causes a permanent loss of capability

   Explanation: CAP 715 states: "Fitness and health can have a significant affect upon job performance (both physical and cognitive)." Even temporary illness can reduce thinking and physical performance. Fitness depends on the person's actual condition and the task, not just permanent impairment or restricted movement.

   Reference: CAA CAP 715: Aircraft Maintenance Engineering Human Factors — Chapter 4, 1.5.1, page 2

5. 5What is an appropriate way to protect the accuracy of an important maintenance discussion when nearby equipment noise masks speech?

   1. A.Move the discussion to an area where noise will not impair communicationCorrect answer: A
   2. B.Keep the discussion beside the equipment and rely on familiar terminology
   3. C.Shorten the discussion by omitting details that require repetition
   4. D.Assume that a colleague's nod confirms every detail was heard

   Explanation: CAP 715 states: "Common sense dictates that important matters are discussed away from noisy areas." Moving the discussion addresses the masking noise. Familiar words, omitted details and assumed acknowledgement do not establish accurate information transfer.

   Reference: CAA CAP 715: Aircraft Maintenance Engineering Human Factors — Chapter 5, 1.4, page 2

6. 6Before starting an unfamiliar physical maintenance task, what should the engineer establish about the available resources?

   1. A.That any missing resources can be replaced by experience after work starts
   2. B.That personnel, equipment, information and facilities can support safe completionCorrect answer: B
   3. C.That equipment availability takes precedence over the need for written information
   4. D.That a task assignment is itself confirmation that every resource is available

   Explanation: CAP 715 states: "Are the resources available to do it effectively (safely, accurately and within the time permitted)?" Planning must check the actual resources needed, including people, equipment, documentation and facilities. Assignment and experience do not prove that resources are sufficient.

   Reference: CAA CAP 715: Aircraft Maintenance Engineering Human Factors — Chapter 6, 1.1.1, page 2

7. 7Two engineers hear the same acronym but assign different meanings to it. What communication requirement has not been met?

   1. A.The message must be delivered through more than one physical channel
   2. B.The sender must use written information instead of speech
   3. C.The sender and receiver must share the code used to convey meaningCorrect answer: C
   4. D.The receiver must have more technical experience than the sender

   Explanation: CAP 715 states: "engineers must have a similar knowledge of technical language, jargon and acronyms." Shared language includes the intended technical meanings. Merely hearing or reading the same symbols does not ensure they are decoded in the same way.

   Reference: CAA CAP 715: Aircraft Maintenance Engineering Human Factors — Chapter 7, 1.2.3, page 2

8. 8An engineer intends to copy a reference number correctly but accidentally transposes two digits while writing it. Which error type does this illustrate?

   1. A.A deliberate violation
   2. B.A mistake in planning the intended task
   3. C.A lapse caused by forgetting to perform the task
   4. D.A slip during execution of the intended actionCorrect answer: D

   Explanation: CAP 715 states: "Slips can be thought of as actions not carried out as intended or planned" The intention is correct but execution is wrong. A lapse concerns an omitted action, a mistake a faulty plan, and a violation a deliberate departure from rules.

   Reference: CAA CAP 715: Aircraft Maintenance Engineering Human Factors — Chapter 8, 1.4.3, page 4

9. 9After identifying a workplace hazard, which two features determine the level of risk to people?

   1. A.The likelihood of harm and how serious that harm could beCorrect answer: A
   2. B.How familiar the work is and whether the workers feel confident
   3. C.How often the written procedure is revised and who approved it
   4. D.Whether a warning sign is posted and whether training is recorded

   Explanation: HSE states: "decide how likely it is that someone could be harmed and how serious it could be." Risk level concerns likelihood and severity. Familiarity, procedure administration and evidence of signs or training do not by themselves assess the potential harm.

   Reference: HSE: Steps needed to manage risk — Assess the risks

10. 10In the SHEL model, which element includes the layout of a maintenance checklist?

    1. A.Hardware
    2. B.Environment
    3. C.SoftwareCorrect answer: C
    4. D.Liveware

    Explanation: CAP 715 states: "Software (e.g. maintenance procedures, maintenance manuals, checklist layout, etc.);" Software includes procedural information and its presentation. Hardware refers to physical equipment, environment to working conditions, and liveware to people.

    Reference: CAA CAP 715: Aircraft Maintenance Engineering Human Factors — Chapter 1, 1.5.1, page 2