The Dirty Dozen and maintenance human factors (A&P General)

Human factors questions are definitions taken almost word for word from chapter 14 of the FAA General handbook, often with the handbook's own examples. Learn the twelve factors and the few models around them and this subject becomes recognition, not reasoning.

Questions and answers, explained

All 12 questions above, with the correct answer and why it is correct. Everything here is on the dirty dozen and maintenance human factors (a&p general).

1. The "Dirty Dozen" is a list of

   • Atwelve FAA violations most often found on ramp checks
   • Btwelve tools that must be accounted for at shift change
   • Ctwelve human factors that degrade safe performanceCorrect
   • Dtwelve inspection items required on every annual

   Why: Transport Canada identified twelve human factors that degrade people's ability to perform effectively and safely and can lead to maintenance errors. The aviation industry adopted them as the Dirty Dozen, including lack of communication, complacency, fatigue, pressure and norms.

   Reference AM.I.L.K2 · FAA-H-8083-30B, Ch. 14 (The Dirty Dozen)

2. An experienced technician skips part of a routine inspection because that item has never been faulty before. Which Dirty Dozen factor is this?

   • AComplacencyCorrect
   • BLack of resources
   • CLack of assertiveness
   • DDistraction

   Why: The handbook describes complacency as developing over time: with experience comes self-satisfaction and false confidence, and a repetitive inspection item may be overlooked or skipped because it has never shown a fault.

   Reference AM.I.L.K11 · FAA-H-8083-30B, Ch. 14 (Complacency)

3. In human factors terms, norms are

   • Athe FAA's minimum standards for maintenance work
   • Bthe torque values listed in standard tables
   • Cthe average error rate in a repair station
   • Dunwritten practices followed or tolerated by a groupCorrect

   Why: Norms are the way things are actually done in a work group, often unwritten. The handbook warns negative norms can detract from the established safety standard, and newcomers tend to adopt them by watching others.

   Reference AM.I.L.K1 · FAA-H-8083-30B, Ch. 14 (Norms)

4. According to the FAA handbook, what is the primary cause of fatigue?

   • APoor lighting in the hangar
   • BA lack of sleepCorrect
   • CWorking with unfamiliar aircraft
   • DExcessive caffeine during the shift

   Why: The handbook: the primary cause of fatigue is a lack of sleep, and the best remedy is enough restful sleep on a regular basis. Stress and overwork add to it; countermeasures such as caffeine only mask it.

   Reference AM.I.L.K4 · FAA-H-8083-30B, Ch. 14 (Fatigue)

5. In the PEAR model of maintenance human factors, the letters stand for

   • APlanning, Execution, Audit, Review
   • BPressure, Error, Awareness, Risk
   • CPeople, Environment, Actions, ResourcesCorrect
   • DProcedures, Equipment, Approval, Records

   Why: PEAR is a memory aid for the four considerations of a human factors program: the People who do the job, the Environment they work in (physical and organizational), the Actions they perform, and the Resources needed to do the job.

   Reference AM.I.L.K4 · FAA-H-8083-30B, Ch. 14 (The PEAR Model)

6. A technician reading a job card unintentionally transposes a torque value of 26 into 62. This is an example of

   • Aa violation
   • Ba latent error
   • Ca negative norm
   • Dan unintentional errorCorrect

   Why: The handbook uses exactly this example of an unintentional error, an accidental deviation from accuracy. Knowingly choosing to deviate from procedures would be a violation, which the handbook says is how an intentional error should be treated.

   Reference AM.I.L.K11 · FAA-H-8083-30B, Ch. 14 (Types of Errors)

7. A technician falls from a ladder that everyone knew was broken but no one had replaced. In human factors terms, the broken ladder is

   • Athe active error
   • Ba latent errorCorrect
   • Ca slip
   • Da lack of knowledge

   Why: The handbook's own example: the active error is the obvious event, falling from the ladder. The latent error is the underlying company issue that led up to it, the broken ladder someone should have replaced.

   Reference AM.I.L.K10 · FAA-H-8083-30B, Ch. 14 (Active and Latent Errors)

8. What is the goal of the Maintenance Error Decision Aid (MEDA) process?

   • ATo find root causes and prevent recurrence instead of placing blameCorrect
   • BTo identify which technician should be disciplined
   • CTo decide whether a repair is major or minor
   • DTo calculate the cost of an incident for insurance

   Why: MEDA is built on the idea that errors result from a series of contributing factors. Its goal is to investigate errors, understand root causes and prevent accidents, rather than simply blaming the person who made the error. It assumes positive employee intent.

   Reference AM.I.L.K3 · FAA-H-8083-30B, Ch. 14 (Maintenance Error Decision Aid)

9. Why is a thorough turnover especially critical when a partially completed job is handed to the next shift?

   • AThe next shift needs it to bill the customer correctly
   • BRegulations require the job to restart from step one
   • CCompleted steps may be hidden and impossible to verify laterCorrect
   • DThe arriving technician must re-torque every fastener anyway

   Why: The handbook: many steps cannot be seen or verified once completed because later installation hides the work, and later steps may depend on earlier ones. The departing technician must explain exactly what has been done so the job is completed correctly.

   Reference AM.I.L.K9 · FAA-H-8083-30B, Ch. 14 (Lack of Communication)

10. Assertiveness, as the FAA handbook uses the term, means

    • Ainsisting on your own way regardless of others
    • Bexpressing concerns and opinions in a positive, productive wayCorrect
    • Cavoiding conflict by keeping concerns to yourself
    • Dcompleting work quickly to meet the schedule

    Why: The handbook defines assertiveness as the ability to express your feelings, opinions, beliefs and needs in a positive, productive manner, not to be confused with being aggressive. Keeping safety concerns to yourself is the Dirty Dozen factor lack of assertiveness.

    Reference AM.I.L.K6 · FAA-H-8083-30B, Ch. 14 (Lack of Assertiveness)

11. An airline's tight schedule pushes a technician to close up a job before every step is checked. Which Dirty Dozen factor is at work?

    • ALack of knowledge
    • BLack of teamwork
    • CLack of awareness
    • DPressureCorrect

    Why: Pressure is the Dirty Dozen factor created by tight schedules and financial expectations to return aircraft to service quickly. The handbook is blunt: maintainers must not let time constraints get in the way of safely finishing a repair. If a job needs more time or help, say so before signing.

    Reference AM.I.L.K9 · FAA-H-8083-30B, Ch. 14 (Pressure)

12. Lack of awareness, as defined in the FAA handbook, is

    • Aa failure to recognize all the consequences of an actionCorrect
    • Bbeing unaware of the latest FAA rule changes
    • Cforgetting to sign the maintenance record
    • Dworking without the right tools

    Why: The handbook defines lack of awareness as a failure to recognize all the consequences of an action, or a lack of foresight, often in experienced technicians who stop thinking through what else a task affects. Working without the right tools is lack of resources.

    Reference AM.I.L.K5 · FAA-H-8083-30B, Ch. 14 (Lack of Awareness)

Drill the whole domain

• Human Factors (6%)

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