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Maintenance
Human Factors TrainingEASA 145 & 66
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Maintenance Human Factors
This training is based on EASA 145, whichrequires
That maintenance organizations put in place amaintenance Human Factors program thataddresses ten (10) maintenance Human Factorsissues, and where
One (1) of the issues is the need to trainmaintenance staff to be competent inmaintenance Human Factors knowledge andskills
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EASA 145 Maintenance Human FactorsTraining Requirements
1. General / Introduction to human factors
2. Safety Culture
3. Human Error4. Human Performance & Limitations
5. Environment
6. Procedures, Information, Tools and Practices
7. Communication8. Teamwork
9. Professionalism and integrity
10.Organizations HF Program
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I. General
Introduction toHuman Factors
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Definition
Human Factors is a technical discipline aimed atoptimizing human performance within a system bycontributing to the planning, design, and evaluation of
tasks, jobs, products, organizations, environmentsand systems in order to make them compatible withthe needs, abilities, and limitations ofpeople.
This Not This
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Where Can Human FactorsBe Applied in Maintenance?
Manuals &Procedures
Training
OperationalControls & Displays
Design forMaintainability
Human/ComputerInteraction
Work GroupProcedures
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SHELL Model
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Variations in Performance & limitations
Physical size & shape
Physical needs (sustenance, sleep etc)
Input/Output Characteristics Information processing
Environmental tolerances (temp, pressure,humidity, enclosed space, stress & boredom)
Liveware
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Ergonomics Tool design & operation
Instrument interpretation
Work space & access
GSE reliability
Liveware Hardware
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Non-physical aspects of systems such as:
Document design & layoute.g. maintenance manual
Symbology and computer programmes
Procedures
Training manualsi.e. content and design
Rules and regulationsi.e. company and authority
Liveware Software
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Extremes of temperature affects thoughtprocesses
Excess noise and vibration affectsconcentration
Shift work causes fatigue making error prone
Liveware Environment
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Leadership, co-operation,teamwork, personality
interactions Staff/management relationships,
corporate culture & climate,company operating pressures
Domestic Pressure
Liveware Liveware
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Causes of Accidents
Source : FSF , 2000
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Causes of Accidents
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
1903 TodayTIME
~80% of accidents are now
due to human error
~20% of accidents are now
due to machine causes
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Maintenance-Related Accidents
Maintenance system failures, due to errorsand/or violations, can affect safety of flight in twodifferent ways:
1. Primary Cause of an accident. Accident is due tothe maintenance/inspection failure. Accident is not inany way due to flight crew action.
2. Contributing Factorto an accident. Accident
chain begins with a maintenance/inspection failure thatis incorrectly handled by the flight crew, ultimatelyending up as an accident (Primary Cause is pilot error).
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Accident Where Maintenance Isthe Primary Cause
Kahului, Hawaii, U.S.A. 1988 Upper fuselage separation 737-200
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Kahului 737 Event
Post incident inspection revealed that there were atleast 240 cracks present at the last inspection prior
to incident.Among the contributing factors to the error of notseeing the cracksLack of resourcesNo proper platform or inspection lights.
FatigueInspection carried out late at night.
Lack of technical knowledgeNot enough inspectiontraining.
ComplacencyDone other aircraft and had not find anycracks.
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Maintenance as a Primary Cause
Data provided in a recent Advance-Notice ofProposed Amendment No xx/2007 from EASA*.
Primary Cause of HF-Related Accidents # of Accidents % of Total
Design 135 3%Production 101 2
Operations (flight crew related) 3038 58
Maintenance 416 8
ATM 66 1
Dispatch 18 0
Loading 129 2
TOTAL HF-Related Accidents 3903 75
Non-HF-Related Accidents 1320 25
TOTAL 5223 100*Data obtained from EASA Safety Analysis & Research. It is based on airliner accidents only, covering the period
1990 to January 2006. Only reports where causal factors have been positively identified are included in the analysis.
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Accident Where Maintenance Is aContributing Factor
Lima, Peru 1996 Tape left on static ports 757-200
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Lima 757 Event
The aircraft's three static ports on the left side wereobstructed by masking tape. The tape had beenapplied before washing and polishing of the aircraft
the day before the accident flight.Work was begun on one shift and handed over tonext mornings shift.
Poor shift handover log was a contributing factor.
Mechanics and pilots both missed tape during walkaround.
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Safety Costs ofMaintenance Events 2003
The International Air Transport Association (IATA)Safety Report 2003 found that in 26% of theaccidents a maintenance-caused event started the
accident chain.
IATA Safety Report 200640%
IATA Safety Report 200720%
IATA Safety Report 200815%
Note: IATA did not distinguish between maintenance asa Primary Cause vs. a Contributing Factor.
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Monetary Costs of Maintenance Error
Maintenance error caused
20% to 30% of in-flight shutdowns (IFSDs) at a
cost of US $500,000 per IFSD50% of flight delays due to engine problems at acost of US $9,000 per hour.
50% of flight cancellations due to engine problems
at a cost of US $66,000 per cancellation.
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Murphys Law
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Summary
About 80% of aircraft accidents today are caused by humanerrors.
Maintenance and inspection errors are the primary cause of
8% of the accidents.Maintenance and inspection errors are a link in the accident
chain in an additional 20% - 30% of the accidents.
Maintenance and inspection errors can also be very costly.
The whole industry (manufacturers, vendors, aviationauthorities, airlines, and maintenance providers) must worktogether to reduce the risk from these errors.
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II. Safety Culture/Organisational factors
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Safety Culture
EASA 145 requires that a maintenanceorganization develop a Safety Culture
within the organization.One way to begin development of aSafety Culture is to put the elements of
a Safety Management System intoplace.
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Safety CultureSafety Management System
Definition of culture/safety culture
Importance of a good safety culture
Elements of a good safety culture
Safety Management System (SMS)
International Civil Aviation Organization
(ICAO)
General characteristics and functions ofan SMS
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Definition of Culture
Culture = Customary beliefs, behaviorpatterns, and traits of a racial, religious, orsocial group
Any organization has a culture of its own
Management style
Morale
Acceptable behaviors
Norms
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Definition of Safety Culture
What is a safety culture as it applies to anaircraft maintenance organization?
A safety culture is a (maintenanceorganization) culture in which safety plays amajor role.
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Importance of a Good Safety Culture
Safety, as it applies to maintenance, hasthree components1. Maintenance actions (e.g., an installation error) can
lead to safety of flight issues2. Mechanic actions can lead to personal safety issues
(e.g., cuts, puncture wounds, and broken bones)
3. Maintenance actions can lead to environmentaldegradation.
A good safety culture will reduce theinstances of all three of these events,reducing the accident rate and, thus,saving lives and money.
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J. ReasonThe Elementsof a Good Safety Culture
Informed CultureA culture in which those whomanage and operate the system have currentknowledge about the human, technical,
organizational and environmental factors thatdetermine the safety of the system as a whole.
Reporting CultureA culture in which people arewilling to report errors and near misses.
Learning CultureA culture in which people havethe willingness and competence to draw the rightconclusions from its safety information system, andthe will to implement major reforms when the need isindicated.
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J. ReasonThe Elementsof a Good Safety Culture
Just CultureA just culture where anatmosphere of trust is present and people areencouraged or even rewarded for providing
essential safety-related information, but wherethere is also a clear line between acceptableand unacceptable behavior.
Flexible CultureA culture that has
organizational flexibility typically characterizedas shifting from the conventional hierarchicalstructure to a flatter professional structure.
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Achieving a Safety Culture
A Safety Culture is achieved over time,requiring:
A commitment to safety from the SeniorManagement down through every worker in theorganization.
A process for achieving safety. This process
often is called a Safety Management System.
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III. HumanPerformance
& Limitations
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Human Performance &Limitations
Normal curve
Human strengths andweaknesses
VisionHearing
Information processing
Attention and
perceptionMemory
Speed/accuracy trade-off
Physical work
Fatigue and sleep
Claustrophobia and
physical accessFitness and health
Alcohol, medication, anddrugs
Repetitive tasks/complacency
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Introduction to Human Performance
Human beings have strengthsand weaknesses
Tasks that do not account forhuman limitations result in: Errors Injuries
If you review a task or workstation, do not ask:
Can it be done?
Ask:
Can it be done safely andcorrectly by the people whodo the job?
Vision
Hearing
Cognition
Strength
Reach
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Humans Are Betterthan Machines in
Detecting small amount of visual and acoustic energy.
Perceiving patterns of light or sound.
Improvising and using flexible procedures.
Reacting to unusual or unexpected events.
Storing very large amounts of information for long periods and recallingrelevant facts at the appropriate time.
Applying originality at solving problems.
Reasoning inductively.
Exercising judgment.
Learning from experience.Use a human operator when a system componentis needed that can think on its feet, process information
in ways that could not be predicted, and can then acteffectively using the result.
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Machines Are Betterthan Humans in
Responding quickly to control signals.
Applying great force smoothly and precisely.
Performing repetitive, routine tasks.
Storing information briefly and then erasing itcompletely.
Reasoning deductively, including computational
ability.Handling highly complex operationsdoing manydifferent things at once.
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Other Major Differences
Machines can be modified, redesigned, andretrofithumans cannot.Humans are born with innate, genetically determined
differences that are shaped by the environment. Innate aptitudes or abilities are developed througheducation and training.
Machines can be manufactured to be identicalwith (nearly) identical output or performance.Humans are not identical and vary across all sensory,cognitive, physical, and performance characteristics.
Specific aspects of human performance can be mademore equal through education and training.
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Vision Performance Issues
Being able to see clearly is vitalin aircraft maintenance andinspection.
Vision requirements are taskbased.
Illumination requirements are
task based.Technicians must recognizetheir individual visuallimitations and capabilities.
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The Normal Visual Field
Provide visual access to workarea... Without excessive bending
For both short and tall peopleVisual access is critical to...
Doing the task
Visual validation of the task
Examples of problems due topoor visual access: Incorrect attachment
Inspection errors
Increased task time
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Colorblindness
Complete color blindness is quiterare.
Most people are actually colordeficient and have problems
seeing red and green.About 10%-15% of males and 1%
of females are color deficient.
Most do not even know.
They learn to compensate with
degrees of brightness andtexture.
If you find you have it, avoiderrors by asking other peoplewhen you are unsure.
An estimation of what the spectrum lookslike for different types of colorblindness.
No Red receptors
No Green receptors
No Blue receptors
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A Quick Colorblindness Test
This is a demonstration.You should see the number 12.
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What Numbers Do You See?
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Recommended Illumination Levels*
Tasks
Illumination Levels in Lux Light
SourceRecommend Minimum
Perceiving small details with low contrast for
prolonged times, or where speed and accuracy are
essential, such as repairing small components,
inspecting dark materials
1650 1075 General service
plus
supplementary
Perceiving small details with fair contrast where speed
and accuracy are not so essential, such as electronic
assembly
1075 540 General service
and/or
supplementary
Prolonged reading, desk or bench work, general office
and laboratory work, such as assembly work and filing
records
755 540 General service
and/or
supplementary
Occasional reading, recreation, reading signs where
visual tasks are not prolonged, such as reading abulletin board
540 325 General service
and/orsupplementary
Perceiving large objects with good contrast, such as
locating objects in a bulk supply warehouse
215 110 General service
Passing through walkways and handling large objects,
such as loading from a platform
215 110 General service
*Illumination requirements for representative tasks (MIL-HDBK-759A)
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The Human Auditory System
The outer ear collects sound
The middle ear channels sound to theear drum
The inner ear converts sound to nerveimpulses
Tiny hair cells (cilia) in the Cochleavibrate with different sounds
Excessively loud noise can result inthe hair cells stretching too far andbreaking
Listening to the same frequency orpitch for a long time can also damagethe hair cells
Listening to loud noise for a longperiod can also cause fatigue
Outer Ear Middle Ear Inner Ear
Ear Drum
Cochlea
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Protect Your Hearing!!
Types of Hearing ProtectionDisposable plugs
Reusable plugs
Custom-fitted plugsEar muffs
Wearing Hearing Protection ProperlyFollow package directions when putting protection on.
Make sure the selected protection fits properly.Maintain hearing protective devices in a sanitary condition.
Make sure nothing interferes with the use of hearingprotectors (e.g., eyeglass frames).
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Sound Intensity Levels
Db Level Example Dangerous Time Exposure
0 Lowest sound audible to ear None
30 Quiet library, soft whisper None
40 Quiet office, living room None
50 Light traffic at a distance, refrigerator None60 Air conditioner at 6 m., conversation None
70 Busy traffic, noisy restaurant Critical level begins
80 Subway, heavy city traffic, alarm clock More than 8 hours
90 Truck traffic, lawn mower, shop tools Less than 8 hours
100 Chain saw, boiler shop, pneumatic drill Less than 2 hours
120 Rock concert in front of speakers, Immediate danger
sandblasting, thunderclap
140 Gunshot blast, jet plane @ 15 m. Any exposure is bad
180 Rocket launching pad Hearing loss inevitable
American Academy of Otolaryngology, Washington, DC
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Information
Processing/Attention and
Perception/Memory
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A Model ofHuman Information Processing.
(Adapted from Wickens, C.D. Engineering Psychology and Human Performance. Columbus, Ohio: Charles E. Merrill Publishing Co., 1984.)
Three types of memory Sensory memory
Working or short-term memory
Long-term memory
Attention (concentration) is a limitedresource, which must be shared between
Observing the situation
Deciding on a response
Executing the response
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Attention and Selection
The first process of memory is attention.
There is much more information in your environmentthan you can process at any one time.
You must make choices (conscious & unconscious)regarding the stimuli to which you will attend.
Early theory was that we could only attend to onething at a time.
That theory is still believed to be true. However, wecan switch our attention quickly, especially if theinformation comes from different channels (e.g.,hearing and vision).
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Working (Short-Term) Memory
This is the memory that we use, for example, whensome one gives us a phone number to call or givesus directions on how to find an office in a building
Working memory lasts only about 20 seconds,although you can make the memory last longer byrepeating the information to yourself in your head
Working memory can hold about 7 + 2 (5 to 9)
chunks of information. For example, you willremember the name
Steven as one chunk of information, not as sixseparate letters.
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Moving Information from Short-TermMemory into Long-Term Memory
All verbal information goes first into the short-termmemory.
When it is rehearsed (recited), part of it goes into
long-term memory.
The rest of it, usually the part we are leastinterested in, returns to short-term memory and isthen forgotten.
Whether new information is "stored" or "dumped"depends, then, on our reciting it out loud and onour interest in the information.
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Accessing Long-Term Memory
Two ways to access your memory:Recallcoming up with the information from memory
Fill-in-the-blank exams
Coming up with a persons name.
Recognitionrecognizing the correct information Multiple choice tests
True/false tests
Recognizing someone that you know.
Recognition is easier than Recall.
Often need to recall information we learned longago. How quickly/reliably we recall it depends on:Activation: How long since we last used the information.
Strength: How well we have practiced it.
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Negative Transfer of Training
When you learn new material, old material that youlearned before is still in long-term memory.
If the new material is similar to the old material but
with some small differences, you can becomeconfused. Example: Mechanic knows how to replace a hydraulic pump on airplaneA. The airline buys a newer model--airplane B.
The pump bolts on airplane A must be torqued to 50 ft lbs
The pump bolts on airplane B must be torqued to 60 ft lbs
Later, the mechanic makes an error by:
Replacing a pump on airplane A and tightening the bolts to 60 ft lbs, or
Replacing a pump on airplane B and tightening the bolts to 50 ft lbs.
MESSAGE: Be sure to check details when things
are almost, but not quite the same.
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Physical Work
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Bio-Mechanics
Human Force
Application
Spine Geometry
Work Posture
Thisimagecannot currently bedisplayed.
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Occupational Risk Factors forCumulative Trauma Disorders
Force
Frequency
Vibration
Posture
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Neutral Position ofHand and Wrist
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OK Avoid
Work Posture - Hand and Wrist
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OK
Avoid
Work Posture - Arm and Shoulder
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OK Avoid
Work Posture - Arm and Shoulder
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Neck Flexion
Neck flexion greater than 30 degrees
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Back Flexion
Back flexion greater than 30 degrees
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Squatting
> 2 Hours per Shift
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Kneeling
> 2 Hours per Shift
Hands Above Head or
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Hands Above Head orElbows Above Shoulders
> 2 Hours per Shift
Repetitively Raise Hands Above
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Repetitively Raise Hands AboveHead or Elbows Above Shoulders
> 4 Times/Minute
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Highly Repetitive Motion Neck, Shoulders, Elbows, Hands
> 4 Times/Minute
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Highly Repetitive Motion andForceful Exertions with Hands
30o
Greater than 30 degrees
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Pinch Grip
Objects weighing > 1 kg per hand
or force > 2 kg per hand
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Pinch Grip Plus Repetitive Motion
> 4 times/minute
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Pinch Grip Plus Wrist Deviation
30o
Greater than 30 degrees
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Power Grip
Objects weighing > 5 kg per hand
or force > 5 kg per hand
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Power Grip Plus Repetitive Motion
> 4 times/minute
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Power Grip Plus Wrist Deviation
Greater than 30 degrees
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Repeated Impact - Hands
> 10 times/hour
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Repeated Impact - Knees
> 10 times/hour
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Intensive Keying and Mousing
> 40 words per minute
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Lifting
> 11 kg or > 5 kg more than
two times/minute
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Pushing/Pulling
> 16 kg of initial force
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Use of Vibratory Tools
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Workstation Design
Design work stations for a range ofpeople, not for the average person
Permit several different workingpositions
Design should start from the pointwhere the hands spend most oftheir time
Work should be conductedbetween shoulder and waist height
Raise the work surface for workthat requires precision, so it iscloser to your eyes
Lower the work surface for workthat requires more force so yourarms are in a more neutral position
Boeing airplanes are designed forpeople from 157 cm to 193 cm
A drill which allows the user tochange grip positions
A component work bench whichholds the component in the centerand the tools around it
Getting a ladder so that you arenot working over your head
Raising a manual to see detailor a component work bench whichmoves up and down.
A component work bench whichholds a hydraulic pump at aboutwaist high
Principle Example
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Fatigue
andSleep
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Fatigue
EASA-145 requires the organisationsplanning procedures to take into
account the limitations of humanperformance, focusing on fatigue.
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Definitions
FatigueA feeling of lack of energy,weariness or tiredness. Also calledtiredness, weariness, exhaustion, or
lethargy. Fatigue is a normal response tophysical exertion, emotional stress, andlack of sleep.
AlertnessVigilantly attentive andwatchful; mentally responsive andperceptive.
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Effects of Fatigue
More than 100,000 car accidents annually inthe US are fatigue-related
Disasters such as:
Chernobyl (Russian nuclear power plant)Three Mile Island (US nuclear power plant)
Bhopal (chemical release in India)
Exxon Valdez (oil supertanker accident in
Alaska)were officially attributed to errors in
judgment induced by fatigue.
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Effects of Fatigue
Overall performancegets worse
Loss of motivation
Slowed reactions
Forgetful
Poor cognitivefunctioning
Thinking
Reasoning/judgment
Problem solving/decision making
Loss of creativity
Withdrawal from socialsituations
Mood changes
Increase alcohol use
Long term health candegrade
Quality of life degrades
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Our Circadian Sleep Wake Clock
Alertn
ess
Low
High
6 am Noon 6 pm Midnight 6 am
Time of Day3-5 am and pm = sleepy9-11 am and pm = alert
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Sleep
Sleep is defined as a state of partial or fullunconsciousness during which voluntaryfunctions are suspended and the body rests
and restores itself.Lying down
Little movement
Do not respond as readily to disturbances
Reversiblecan wake up
Observed in all mammals, all birds, and manyreptiles, amphibians, and fish.
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Sleep
Still not totally sure why we need sleep, but thereare two theoriesEnergy conservationsleep to conserve energy (old theory)
Restoration(new theory)
Neural circuits in the brain are rewired
Memory is consolidated and strengthened
Short-term memory items move into long-term memory
Growth hormone levels are restored
Blood pressure drops
The cells in your organs are strengthened by protein synthesis Sleep breaks your stress pattern.
Also, we know that bad things happen if we donot sleep.
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Effects of Missing Sleep
A person who loses one nights sleep will generallybe irritable and clumsy during the next day and willeither become tired easily or speed up because of
adrenalin.After missing two nights sleep, a person will haveproblems concentrating and will begin to makemistakes on normal tasks.
Three missed nights and a person will start tovisually hallucinate and lose grasp of reality.
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How Much Sleep Do You Need?
Depends onAgeHealthCircadian rhythmBody metabolismPhysical exercise levelThe quality of the sleepAmount of recent sleepBody temperaturePersonal differences.
Magic number of 8
hours of sleep is an
average.
Short sleepersNeedaround 6 hrs of sleep.
Long sleepersNeedaround 9 hrs of sleep.
1 in 25 people needmore than 10 or lessthan 5 hrs of sleep.
Avoiding FatigueNo Shift Rotation
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Avoiding Fatigue No Shift RotationGetting a Good Nights Sleep
Get up and go to bed at the same time.
If you are tired, go to bed early.
Use your bed only to sleepno reading, eating, etc.
Keep the bedroom dark, quiet, and cool (58F/15C).Exercise in the morning or early afternoon, not evening.
Do not eat a heavy meal before bed--a light snack at most.
No alcohol before bedtime, no caffeine after early afternoon,and avoid nicotine.
Quit worrying about falling asleepit keeps you from fallingasleep!
Stop looking at that clock! Get up if you are not sleeping.
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Avoiding Errors While Fatigued
Admit you are tired!
Remain physical to remain alert.
Exercise/stretch at frequent intervals.
Talk to people.Drink plenty of liquids.
Take a nap.
Avoid tedious, boring work.Work with somebody else so you can catcheach others errors.
Go back over and check your work.
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Drugs and Diet
Using drugs to get to sleep should be a last resort, because these drugsdecrease REM and deep sleep.
But, remember, there are drugs in food, also (like caffeine in coffee, tea,soft drinks, and chocolate).
Thus, it makes sense to approach food and drugs together.
Food and drugs release chemical that interact with our basic body rhythms.This interaction is one cause of the varied effects they produce.
One step in controlling the bad effects of foods and certain drugs is tocontrol when we consume them. If you are a morning person, the use of uppers like coffee and sugar-coated
cereal in the morning makes no sense.
Another control strategy is to avoid the combined consumption of food anddrugs that have similar effects. For example, combining downers, such as alcohol, sleeping pills, and pain
medication can be particularly dangerous.
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Drugs and Diet
Food in the stomach causes the stomach walls to stretch.The more the stretch, the stronger the signal to the body tosend blood to the stomach to aid digestion.
Diverting too much blood to the stomach by overeating cancreate a shortage of blood elsewhere, like your brain, whichcauses you to feel sluggish following a big meal.
Eating frequent, smaller meals is preferable to eating a fewlarge meals before and during work.
Eating smaller meals in the hours prior to heavyphysical work is a key dietary strategy for shift
workers.
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Physical Fitness
The Drug and Diet control strategies that we have discussedare meant to decrease the build up of stress resulting fromshift work.
However, some stress will still occur.
One factor that clearly improves our ability to cope withstress is physical fitness.
Shift work tends to drain your energy levels; fitness tends to build upyour energy levels.
Physical activity can burn off excess energy and start the cycleleading to a relaxed state that leads to good deep (non-REM) sleep.
Regular physical activity can help stabilize body rhythms and ishelpful in speeding the resettling of body rhythms in the first few daysof a shift change.
Putting It All Together to Get a
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Putting It All Together to Get aGood Sleep after Your Night Shift
Determine how much sleep you need and try to get it everyday. Use naps, as necessary.
Mental relaxation before bedPhysical relaxation before bedControl your drugs and dietGet physically fitDeal with any sleep-related medical problemsKeep the bedroom dark, quiet, and cool (15C)
Use sun-blocking shades
Work with family and neighbors for bedroom quiet
Wear sunglasses on the drive home to fool your brainTake a nap before the night shift starts in addition to your
after-shift sleep.
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Repetitive Tasks
Complacency
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Complacency
Complacency = Self-satisfactionaccompanied by unawareness of actual dangersor deficiencies.
Mechanics can become complacent when theyhave done a task over and over again withoutmaking an error.
Inspectors can become complacent when they
have done an inspection many times beforewithout finding a problem.
We must fight complacency!
Complacency
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p yOne of the Dirty Dozen
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Environment
Stress and anxiety
Definition
Why worry?
Symptoms
Stressors
Physical
Psychological
Conditions of thework environment
Cold
Heat
Illumination
Noise level
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What Are Stress and Anxiety?
Stress is a physiological reaction to physical and psychological factors(stressors) in our environment.
Anxiety (also called angst or worry) Is a psychological and physiological state characterized by somatic,
emotional, cognitive, and behavioral components. It is the displeasing feeling of fear and concern in either presence or absence
of psychological stress.Anxiety can create feelings of fear, worry, uneasiness, and dread.Anxiety is also considered to be a normal reaction to a stressor.
In other words, stress and anxiety are about the same thing.
Stress/anxietyStressors Adaptations
Positive
Negative
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Stress/Anxiety and Performance
Time Magazine December 5, 2011
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Physical & Psychological Stressors
Physical stressors Illness
Acute
Chronic
Environment Temperature
Vibration
Noise
Fumes
Fatigue Shift work
High work load.
Psychological stressorsUnpredictability
Uncertainty
Uncontrollability
Bereavement/tragedy
Daily annoyances Time pressure
Peer pressure
Management pressure
Chronic stressors Home environment
Work place pressures.
Why Worry About Threat
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Why Worry About ThreatStress/Anxiety?
Human Error
Injury
Illness
Reduced
Productivity
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Conditions of the
Work Environment
Another Effect of Heat and Cold
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Another Effect of Heat and Coldon Work Performance
Some airlines have noted an increase inmaintenance errors in line maintenance during thesummer. Why? It is so hot outside or on the aircraft that the mechanicworks quickly so that he can get back to the air-conditioned building.
Speed/accuracy trade-off applies, so errors increase.
Similar thing happens during winterWork quickly to get in out of cold.
Have to wear heavy gloves and clothing, so that it isharder to do the work. Thus, errors increase.
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V. Procedures,Information, Tools, and
Practices
Procedures, Information,
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Procedures, Information,Tools, and Practices
Visual inspection
Task inspections/duplicate inspections
PlanningWork logging and recording
Procedurepractice mismatch
Technical documentationaccessand quality.
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Visual Inspection Outline
Definitions
Visual inspectionsearch and decision
Factors affecting visual inspection
Task Factors
Subject Factors
Equipment Factors
Environment Factors
Social Factors
Concept of Damage Tolerance
Systems, Structural, and Zonal Inspections
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Visual Inspection
Over 80% of inspections on aircraft are visualinspections.
Visual inspection is often the most economical and
fastest way to find defects on an aircraft.Airframe manufacturers and airlines depend onregular visual inspections to ensure the continuedairworthiness of their aircraft.
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Definition of Visual Inspection
Visual Inspection means inspection using either orall of human senses such as vision, hearing, touchand smell.
Visual Inspection typically means inspection usingraw human senses and/or any non-specializedinspection equipment.
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Types of Inspection
General visual inspection (GVI)
Detailed inspection (DET)
Special detailed inspection (SDI)
Definition of General Visual
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Definition of General VisualInspection (GVI)
A visual examination of an interior or exterior area,installation or assembly to detect obvious damage,failure or irregularity. This level of inspection ismade from within touching distance unless
otherwise specified. A mirrormay be necessary toenhance visual access to all exposed surfaces inthe inspection area. This level of inspection ismade under normally available lighting conditionssuch as daylight, hangar lighting, flashlight or
drop-light and may require removal or opening ofaccess panels or doors. Stands, ladders orplatforms may be required to gain proximity to thearea being checked.
Definition of a Detailed Inspection
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e t o o a eta ed spect o(DET)
An intensive visual examination of a specificstructural area, system, installation or assembly todetect damage, failure or irregularity. Available
lighting is normally supplemented with a directsource of good lighting at an intensity deemedappropriate by the inspector. Inspection aids, suchas mirrors, magnifying lenses, etc. may be used.
Surface cleaning and elaborate access proceduresmay be required.
S f O
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Some of the Operating Rules
Normal cleanup procedures are to be used prior toconducting general visual or detailed inspections. Specifiedcleanup procedures are to be used for special detailedinspections, if necessary. Sealant and corrosion protection
finishes should only be removed when specified andrestored in accordance with the Corrosion PreventionManual after the task is completed.
Excessive dust, debris, or overspray of corrosion inhibitingcompounds found during any inspection are considered tobe an unsatisfactory condition possibly reducing the fireresistance of the airplane design. Cleanup of thesematerials should be a standard part of maintenance activity.
Definition of a Special
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pDetailed Inspection (SDI)
An intensive examination of a specific item(s),installation or assembly to detect damage, failure orirregularity. The examination is likely to make
extensive use of specialized inspection techniquesand/or equipment.
Special detailed inspections are to be used whenspecified for inspecting hidden details or may be used asalternatives to detailed inspections.
NDT
Borescope
Typical Aircraft Defects Found by
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Visual Inspection
Typical airframe defects that can be found by visualinspection includeCracks
Corrosion
Disbonding
Other defects that can be found by visualinspection includeSystem and component wear
Accidental damageEnvironmental damage from long-term storage, sunlight,etc.
Factors InfluencingVi l I ti
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Visual Inspection
Task Factors
Subject Factors
Equipment Factors
Environment Factors
Social Factors
T k F t
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Task Factors
Size/complexity of the object searchedingeneral, search time is linearly related to eithersearch field area or number of inspectable items inthe field.
Number of different types of defectsthegreater the number of types of defects, the slowerthe search performance and/or the lower the hitrate.
Defect/background contrasthigherdefect/background contrast produces faster andmore accurate searches.
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Task FactorCompanyInspection Instructions
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Inspection Instructions
Before certifying any work, you must be satisfied that allcomponents, parts and materials utilized have been obtainedfrom approved sources, are of the correct specification, and arecompletely serviceable. You must also ensure that all work are
performed in accordance with current and approved MaintenanceSchedules, Maintenance Manuals, Overhauls Manuals, RepairTest Schedules/Capabilities List, Drawings or any other relevanttechnical publications, and that all applicable MandatoryModifications, Inspections or any other special requirements havebeen duly carried out. In the case of repairs not covered by theapproved technical publication, all work performed must be inaccordance with the approved instructions of the equipmentowner, e.g., Engineering Notes issued by the EngineeringDepartment.
S bj t F t
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Subject Factors
Inspector demographicsage, experience, and gender (noaffect)
Trainingnot the same as experience. Even experienced inspectorscan improve their performance (often dramatically) with a well-designedtraining program, which is based on a task analysis and which providesKnowledge of Results to the trainees.
Visual performancenot related to visual acuityas measured by a Snellen Chart. The size of the visuallobe is a predictor of inspector performance. However, studies done by the US FAA found that 20/20
vision or correctable to 20/20 should be requiredfor inspectors.
Cognitive performancepeople with the ability to dis-embedobjects from a complex/confusing background make better inspectors.
Hidd Fi E l
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Hidden Figure Example
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Hidd Fi E l
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Hidden Figure Example
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Inattentional Blindness and
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Human Errors/Accidents
Someone performing a task simply fails to see what shouldhave been plainly visible and cannot explain the lapseafterwards.
Inattentional blindness causes accidents when attention
mistakenly filters away important information, due to acombination of factors: low conspicuity, divided attention, highexpectation, low arousal.
People are unaware of the blindness. Training mainly affect
conscious, voluntary behavior.
Equipment Factors
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Equipment Factors
Magnificationincreasing magnification may onlychange the speed-accuracy trade-off with highermagnification improving target detection at theexpense of speed.
Field integrationusing a known perfect itemfor comparison during the inspection.
Visual enhancementspecific to NDI.
Human/machine function allocationspecificto NDI. Typically shows that a hybrid of human andmachine functions work better than either alone.
Environment Factors
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Environment Factors
Visual environmentcorrect lighting is important both forphysical inspection and to avoid glare in computer-basedinspection.
Auditory environmentno necessarily clear affects,although some studies show that noise >90 Db worsenedinspection performance.
Thermal environmentsome data to suggest that reallyhot and really cold environments have a negative affect on
inspection.Workplace comfortno data. However, the myth that
comfortable inspectors lose vigilance has been refuted.
Social Factors
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Social Factors
Working perioddetection performance decreases rapidlyover the first 20-30 minutes of a vigilance task (e.g., watchingradar), although this phenomenon is hard to replicate in typicalvisual inspection tasks.
Job designrest periods have been shown to improveperformance.
Supervision, instruction and other pressuresfromsignal detection theory, we know that criterion used by an inspectorfor reporting defects is influenced by the sum of all biases on theinspector. These biases are affected by a priori probability of adefect and also by the perceived costs of misses and false alarms,
which can be affected by supervisory instructions/reprimands.Information environmentboth feedback of inspection
performance (knowledge of results) and feed forward information(where to look for a defect) have been shown to improve inspectionperformance.
Summary
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Summary
Over 80% of inspections on aircraft are visualinspections, which are often the most economicaland fastest way to find defects on an aircraft.
Visual Inspection means inspection using either orall of human senses such as vision, hearing, touchand smell.
A visual inspection includes a search and adecision. The decision criteria can be influenced
by outside factors, such as management pressure.Common aircraft visual inspections include systeminspections, structural inspections, and zonalinspections.
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Error Capturing/
Task Inspectionsand Duplicate
Inspections
Error Capturing
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Error Capturing
Error capturing = Adding a task to find amistake.
Common error capturing tasks
Operational/functional checks
Mechanic/pilot pre-flight walk around checks
Task inspections/duplicate inspections.
Task Inspection
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Task Inspection
Task (Job) cards typically have two types of signoff:
Worked by (Discussed later under Norms.)
Checked by
What does SIAECs GMM say the checked byperson is supposed to do in order to feelcomfortable in signing off the task or sub-task?
Supposed to watch the whole task, or the critical parts of
the task, being performed?Must have a high degree of confidence that the work hasbeen carried out correctly.
What Standard Do You Inspect To?
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What Standard Do You Inspect To?
Many are found in the Aircraft Maintenance Manual(AMM)
Chapter 20 Airframe Standard Practices
Chapter 51 Standard Practices and StructuresChapter 70 Engine Standard Practices
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Planning of Tasks,
Equipment, andSpares
Planning of Tasks,E i t d S
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Equipment, and Spares
Planning of Tasks, Equipment and Spares
EASA 145 does not require a procedureon the planning of work.
EASA 145 and AMC material clarifies theobjective of good planning and includesthe elements to consider when
establishing the planning procedure.
Planning of Tasks, Equipment,and Spares
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and Spares
Planning is critical to ensure that there areadequateAppropriately qualified and alert maintenance staff
Tools
Equipment
Material
Maintenance data
Facilities
for scheduled and un-scheduled maintenance.Long-term planning.
Short-term planning.
Planning of Tasks,Equipment & Spares
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Equipment & Spares
Planning consideration should be given to
Logistics.
Inventory control.
Space availability (hangar and floor space).
Man-hours estimation.
Man-hours availability.
Preparation of work.
Co-ordination with internal and external suppliers.
Scheduling of safety-critical tasks during periods when staffare likely to be most alert, and avoiding periods whenalertness is likely to very low, such as early morning ornight shift.
Work Logging and Recording
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Work Logging and Recording
Importance of proper work logging/recording
All work on an aircraft should be documented.
Work sign-offs should occur soon after the sub-
task is completed. Do not wait until the end ofthe task to sign off all worked by blocks.
Any work done on the aircraft that is notcovered in the maintenance manual (e.g.,loosening a clamp on a wire bundle in order toget access to a part) should be recorded,typically with a non-routine card.
Technical Documentation
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Technical Documentation
EASA 145 addresses technicaldocumentation (poor maintenance data)
Inaccurate, ambiguous, incomplete
maintenance procedures, practices,information or maintenance instructionscontained in the maintenance data used by
personnel must be reported to the author ofthe data.
Technical Documentation
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Technical Documentation
The US Federal Aviation Administrationrecently did a study of aircraft maintenancemanuals (AMMs). They found that:
The manuals rarely had technical errors in them,but
The manuals were not written by mechanics,meaning that the order of the tasks typically doesnot follow the way in which a mechanic wouldactually do the task.
Documentation andMaintenance Errors
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Maintenance Errors
MEDA investigations have found thatdocumentation is the most frequent contributingfactor to maintenance error.
Problems includeNot used (50% in MEDA investigations)
Not understandable
Incorrect step
Conflicting information
No illustration.
Poor illustration
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VI. Teamwork
Team Behavior
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Team Behavior
Team Behavior- The way people behavewhen part of a team.
Overview
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Overview
What AffectsTeam Behavior?
Responsibility
Motivation
Norms
Culture
Effective TeamBehaviors
Communication
Assertiveness
SituationAwareness
Leadership
Responsibility
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Responsibility
Responsibility is...Recognizing that you can affect the teams success.
Choosing to act to help that success.
In a team, we tend to feel lessresponsible.Someone else will do it.
The whole team agreed.Nobody saw me, it could be anyone.
Social Influence
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Social Influence
How behavior is influenced by thesocial environment and the presence ofother people
Obedience to authority
Conformity to group/team.
Examples of TakingResponsibility
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Responsibility
Admitting and fixing errors.
Saying something about a situation whenyou know there is something wrong.
Addressing non-critical problems Picking up debris from the ramp
Finding the safety wire you dropped.
Maintaining professional responsibility. Maintaining technical currency.
ProfessionalismSome Examples ofUnprofessional Behaviors in Maintenance
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Unprofessional Behaviors in Maintenance
Memorizing tasks instead of using manuals/cards.
Not using torque wrenches or other calibrated tooling.
Troubleshooting through experience, instead of using theFault Isolation Manual (FIM).
Deviating from maintenance manual procedures.Failing to attach Do Not Use tags when pulling
circuit breakers and switches.
Skipping operational or functional tests.
Signing off for tasks neither seen nor checked.Providing minimum information in task handover log.
Failing to document work not specified in the manual (e.g.,loosening a clamp on a wire bundle).
Why Do We SeeUnprofessional Behavior?
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Unprofessional Behavior?
Behavior starts to stray from the professionalstandard for various reasons (uncomfortable, timeconstraints, calibrated equipment unavailable).
Supervisor does not intervene.Staff believe that supervisor does not care.
Behavior is seen as low risk.
Unprofessional behavior becomes the norm.
Existing workers put peer pressure on new hires toconform to these behaviors.
Why Do We SeeUnprofessional Behavior?
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Unprofessional Behavior?
Supervisor actually rewards unprofessionalbehavior.
Weve got 4 days of work to do in 2 days. I dont carewhat you do, just get it done. I am going into my officeand closing the door. [After meeting the 2-day deadline.]Way to go guys!! Pizza for everybody.
Supervisor threatens punishment for carrying outprofessional behavior.
What do you mean you dont feel qualified to do the job?Youre trained. Youre certified. Go out there and do thatwork. You want to keep your job, dont you?
Then How Do We Move Back toProfessional Behaviors?
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Professional Behaviors?
What not to do
Pick out an offender and punish him/her in frontof their work group.
Threaten staff.
Then How Do We Move Back toProfessional Behaviors?
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Professional Behaviors?
What you should doManagement decides what behaviors are desired.Management and labor meet to agree on the newbehaviors. Address issues brought up by labor, e.g.,
Time it will takeAvailability of equipment, calibrated tools, parts, etc.
Supervisors are provided training on new expectations No threats to staff if they are doing correct behavior. Reward correct behavior and model correct behavior.
Labor told of progressive punishment for failure to exhibitnew behaviors Verbal warning Letter to file Time off without pay.
Motivation
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ot at o
Motivation = A process within a person thatcauses the person to move toward a goalthat is rewarding.
Two types of motivation:IntrinsicWe move toward a goal because ofrewards that are internal to ourselves (e.g.,feelings of satisfaction or accomplishment).
ExtrinsicWe move toward a goal because ofrewards that are external to ourselves (e.g.,praise, a good grade on a test, or money).
Motivation Affected by Beliefs
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y
Motivation is determined both by
The intrinsic orextrinsic reward, and
The beliefthat effort will result in achieving the
reward.Example: Someone who does not believe they canwin a race will not be motivated to try hardto prepare for and win the race,
no matter how badly they wantthe $100K prize money.
Performance = Skill X Motivation
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Performance is determined by BOTH:
Skill
&
Motivation
Example: Someone with medium skills
and high motivation can out performsomeone of high skills and no motivation.
Implications for Management
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p g
Management must not only provide hygiene factorsto avoid employee dissatisfaction, but must providemotivation factors intrinsic to the work itself in orderfor employees to be satisfied with their jobs.The job should have sufficient challenge to use the fullabilities/skills of the employee.
Employees who demonstrate increasing levels of ability/skill should be given increasing levels of responsibility.
If a job cannot be designed to use an employees full
abilities/skills, then the organization should considerreplacing the employee with one who has fewerabilities/skills. If an employees abilities/skills cannot befully used, then there will be a motivation problem.
Norms
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Definition: Typical behavior in a social group ororganization.
Norms are simply the state of actual conditions
They can be effective or ineffective in theperformance of quality work
Tagging connectionsWearing appropriate
safety equipmentFollowing check lists
and procedures
Some Ineffective NormsWe Have Seen at Airlines
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We Have Seen at Airlines
Memorizing tasks instead of using manuals/cards
Not using torque wrenches
Troubleshooting through experience, instead of using the FaultIsolation Manual (FIM)
Deviating from maintenance manual proceduresFailing to attach Do Not Use tags when pulling circuit breakers
and switches
Skipping functional or operational tests
Signing off for tasks not seen nor checkedProviding minimum information in shift handover log
Failing to document work not specified in the manual (e.g.,loosening a clamp on a wire bundle)
Norms
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The Asch studies suggest that new staffwill quickly pick up the existing norms intheir work group. If these are norms like
Memorizing tasks instead of usingmanuals/cards
Not using torque wrenches,
then new staff will quickly learn these
behaviors.
Procedural Non-Compliance
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p
EASA 145 requires that procedural non-compliance be addressed. Very important!There is an assumption that people will follow theprocedure as written.
When this assumption is broken, the whole basis of thesafety system is put at risk.Maintenance requirements, therefore safety, are basedalmost solely on an assumption that people will follow theprocedures.
Therefore, maintenance organizations should:Not allow procedural non-compliance to become anormal behavior (norm), and
Make sure written procedures are easy to follow so thatthey will be used.
Signing Tasks Not SeenNor Checked
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EASA 145 requirement to address thisissue.
New Alternate Means of Compliancematerial elaborates on the meaning ofsign-off and the need to check orinspect the task before signing off.
Signing Off Tasks
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g g
A sign-off is a statement by the competent personperforming or supervising the work that the task orgroup of tasks has been correctly performed. Thisis a worked by sign-off, not a QC inspection sign-
off nor a release to service sign-off.Research has shown that many maintenancetasks, which are carried out by workers who are notcompetent to sign off on their own work (e.g.,
temporary staff or trainees), are signed-off unseenby the person supervising the work.
Signing Off Tasks
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g g
Some airlines have one sign-off for each task card.Other airlines have sign-offs for each sub-task withina task card.
Signing off small groups of tasks (sub-tasks)Will help prevent situations where a technician is calledaway from a task (to do another task or at shift end), andthe person picking up the previous task has no record ofwhat has been completed on the task, and
Will encourage a mechanic to continue with the task up to
the next break point before leaving the task (e.g., either totake a break or end the shift).
Sign-off points would be determined by M&E asappropriate to the nature of the work.
Signing Off Tasks
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CAP 716 statesSign-offs should be considered as a mechanism for
ensuring that all steps in the task have been carriedout correctly
Not a method for knowing whom to blame if the taskis not done correctly.
It is expected that the person signing off anotherswork view or inspect the work before signing off.
However, CAP 716 states, It is understood that, in
some cases, the person signing-off the taskwill beunable to view or inspect, in detail, the work whichhas been carried out, but it is important that thatperson has a high degree of confidence that the workhas been carried out correctly.
Effective Team Behaviors
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Communication
Assertiveness
Situation Awareness
Leadership.
Communication
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Communication - The ability to clearly andaccurately send and acknowledge informationand to provide useful feedback.
Basic Communications Model
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Sender
Message
Receiver
Feedback
ENVIRONMENT
Communication Modelin the U.S. Nuclear Industry
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y
Sender
1. Message
Receiver
ENVIRONMENT
2. Feedback
3. Feedback
Senders Responsibility
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Communicatinginformation clearly.
Covering timelyinformation accurately.
Requesting verification of
feedback.Verbalizing plans.
Receivers Responsibility
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p y
Acknowledge communications.
Repeat information.
Paraphrase information.
Clarify information.
Provide useful feedback.
Barriers to EffectiveCommunication
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Passive listening
No feedback
Poor feedback.
Not using the rightwords.
Inappropriate method.
Vague or lateinformation.
Active Listening
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g
DO NOT
Argue about things.
Bring up things that are notimportant.
Plan out your words whilethe other person is talking.
Think about other thingswhile the other person istalking.
DO
Ask good questions.
Make eye contact.
Use positive bodylanguage.
Repeat back using yourown words to make sureyou understand.
Written Communication
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Written communication can be hard. No visual feedback to tell you if the reader
understands.
The reader cannot ask questions.
Make sure that your writing is: Correct
Complete Clear.
Use computer spell checker.
Shift and Task Handover
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EASA and the FAA require a shift and taskhandover procedure acceptable to theNational Aviation Authority.
Incident investigation data shows that taskhandovers are one of the major contributingfactors to error-caused events.
Shift and Task Handover
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The primary objective of handovers is to ensure that allnecessary information is communicated between the out-going and in-coming personnel.
Effective handovers depend on three basic elements:
1. The outgoing persons ability to understand andcommunicate the important elements of the job or taskbeing passed over to the incoming person.
2. The incoming persons ability to understand thisinformation.
3. A formalized process for exchanging informationbetween outgoing and incoming persons and a placeand time for such exchanges to take place.
Shift and Task Handover
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Organizations should have a recognizedprocedure for task and shift handovers which allstaff understand and adhere to. This procedure
should be listed in the GMM.The procedure should provide for sufficient timeto be made available by way of a shift overlap20 to 30 minutes is considered good practice.
Aids to Effective Communicationat Shift Handover
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If only one communication method is used there is arisk of erroneous transmission. For this reasoninformation should be repeated using more thanone method.
While all essential information (especially the detailedstatus of tasks) should be recorded in written form, itis also important to pass this information verbally inorder to reinforce it. Then feedback/questioning canbe used to test ones understanding of the handover,
which increases accuracy.The ability for two-way communication to take place is,therefore, important at shift handover.
Aids to Effective Communicationat Shift Handover
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A part of the shift handover process is to helpdevelop a shared mental picture of themaintenance system, aircraft configuration, tasks inwork etc. This is particularly true when deviations
from normal working has occurred, such asHaving the aircraft in the flight mode at a point in amaintenance check when this is not normally done.
When people have returned following a lengthy absence(the state of things could have changed considerably
during this time) andWhen handovers are carried out between experiencedand inexperienced personnel.
In all these cases handovers can be expected totake longer.
Aids to Effective Communicationat Shift Handover
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Written communication is helped by thedesign of the documents, like the handoverlog, which consider the information needs of
those people who are expected to use it.Involve the people who conduct shift handovers
Ask them what key information should be included andWhat format it should be in.
This helps accurate communication and gets theirbuy-in, which contributes to its use andacceptance of the process.
Handing Over a Task Directly toAnother Person
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When the task is being directly handed over tosomeone who is present, the task handover shouldbe done face to face using verbal and writtencommunication.
In these cases the written element is normally thetask card or non-routine process sheets. Theseshould be accurately completed and clearly identifywhere in the task the work ended.
Any deviations from normal working practices orprocedures must be clearly highlighted with thenon-routine sheets.
Handing Over a Task for Somebody toComplete Later
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It is common that a job is left incomplete during a shift.
In these cases it is often not known who will eventually pickup the job of completing and certifying the release toservice.
These situations present a far greater risk and challenge toeffectively communicate the stage of task accomplishmentand what is required to complete the job.
Face to face communication is not possible. Therefore, totalreliance has to be placed on written communication. Thisprovides no redundancy or an opportunity to question andtest a true understanding by the person expected to finishthe job.
Handing Over Non-Scheduled Tasks
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Complex or lengthy non-scheduled tasks should always bebroken down into a number of discrete steps using stage sheetsor process sheets.
Many incidents have occurred when people have started a non-scheduled task, but had to leave before it was finished without
anybody to handover to.These situations are normally associated with time pressure or
emergency situations.
It is vital that time is taken by the person leaving the job to recordin detail what activities have taken place and what is requiredto complete the job. Record this on stage sheets andemphasize any deviations from the maintenance manual.
Management and supervisors have a responsibility to ensure thatadequate time is given to maintenance staff to record their work,if the task is not completed for any reason.
Cultural Differences in Communication
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Culture = Customary beliefs, behaviorpatterns, and material traits of a group(organization).
Some of these beliefs deal withcommunication issues.Do not admit to mistakes.
Indirect (not straightforward) communications.
Pilots will not talk to maintenance staff, etc.
Discuss how the participants national/organizational cultures affect communication.
Assertiveness
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Assertiveness - The willingness to activelyparticipate, and the ability to state and maintainindividual position.
What Is Assertiveness?
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Providing relevant information without being asked.
Making suggestions.
Asking questions as necessary.
Confronting ambiguities.
Willingness to make decisions.
Maintaining position when challenged until convincedby the facts.
Clearly stating positions on decisions and procedures.
Refusing an unreasonable request.
If a disagreement exists, take the most conservative
action until more information is available.
Situation Awareness
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Situation Awareness - The ability to maintainawareness of what is happening on the ramp or thehangar, as well as what is happening on the task.
Situation AwarenessIs the Ability to...
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See elements (e.g., people and equipment) inthe work environment.
Where they are now.
Whether they are moving or stationary.
Understand the importance of what you see,especially with regard to hazards/problems.
Project the status of the elements for the nearfuture (i.e., determine future implications) inorder to detect situations requiring action.
Barriers to Situation Awareness
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Insufficient communication
Fatigue/stress
Task overload/underload Groupthink mindset
Press-on mentality
Degraded operating conditions.
Overcoming Barriersto Situation Awareness
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Actively question/evaluate.
Use assertive behavior when necessary.
Analyze/monitor situation continuously.
Leadership
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Leadership - The use of influence to direct and
coordinate the activities of the members of a group
toward the accomplishment of group objectives.
Types of Leadership
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Designated - Leadership by authority,position, rank, or title. Formal/permanent.
Functional - Leadership by knowledgeor experience.
Informal/temporary.
Designated Leadership BehaviorsCompany Level
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Inspire a shared vision, develop a mission, and establishstandards that help the organization achieve its next stageof development.
Foster teamwork, collaboration, and ownership and motive
team members by recognizing/rewarding individual andteam contributions.
Plan and manage change efficiently and nurture thestrengths of followers to facilitate goal directive activities.
Serve as a symbol of the group and influence others beyondthe group to achieve mutually workable arrangements.
Establish an environment that is conducive to learning.
Functional Leadership BehaviorsCrew Level
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Direct and coordinate crew activities.
Delegate tasks to crew members.
Ensure crew understands expectations.
Focus attention on critical aspects of situations. Keep crew informed of task/shift information.
Ask crew members for relevant task/shiftinformation.
Provide feedback to crew on their performance.
Create and maintain a professional atmosphere.
Effective Functional Leadership
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Make suggestions; do not dictate.
Encourage crew to participate.
Lead by inspiration.
Provide feedback to the crew.
Barriers To EffectiveLeadership
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Micro-management - failure to delegate
Poor interpersonal skills
Easily frustrated Pressures crew members to perform
Unable to adapt to new situations
Rigidity.
Summary
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Factors that affect theway that people behavewhen part of a teaminclude
Obedience to authority
Conformance to team
Amount of responsibility
Motivation to do a good
jobWork group norms
Work group and nationalculture.
Effective teambehaviors includeGood communication,including active listening
AssertivenessSituation awareness
Leadership.
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VII. Human Error/Incident
Investigation
Human Error/IncidentInvestigation
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Errors and violationsTypes of errors
Error models and theoriesReasons Swiss Cheese modelBoeing Maintenance Error DecisionAid (MEDA) contributing factors model
Incident InvestigationPractice
Definitions of Error and Violation
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An erroris a human action (behavior)that unintentionally departs from theexpected action (behavior).
A violation is a human action(behavior) that intentionally departs
from the expected action (behavior).
Violations
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Violations are often made by well-intentioned staff trying to finish a job, notstaff who are trying to increase comfort or
reduce their work load.There are several types of violations
Routine
Situational
Exceptional
Violation Definitions
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RoutineThese are common practice.Often occur with such regularity that they areautomatic. Violating this rule has become a
group norm. Often occur when the existingprocedure does not lead to the intendedoutcome. Condoned by management.
Violation Definitions (contd.)
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SituationalOccur as a result of factorsdictated by the employees immediate workarea or environment. Due to such things
asTime pressure
Unavailability of equipment, tools, or parts
Insufficient staff
Lack of supervisor/degreed engineer to askquestions to.
Violation Definitions (contd.)
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ExceptionalMechanic/inspector willfullybreaks standing rules while disregarding theconsequences.
These are very rare in our business!
Errors and Violations
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Errors have been the focus of research, so we havemore theories of why errors occur than theories ofwhy violations occur.
However, errors and violations often occur together
to produce an unwanted outcome. Data from theU.S. Navy suggest that
~20% of the events are caused by a violation only~20% of the events are caused by an error and a
violation, and~60% of the events are caused by an error only.
Types of Maintenance Error
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Maintenance Error= Error by amechanic/engineer/inspector that leads toproblems on the aircraft.
Installation errorsServicing errorsRepair errorsFault isolation/inspection/testing errors
Errors causing foreign object damage (FOD)Errors causing equipment damageErrors causing personal injury.
Human Error in AircraftMaintenance: UK CAA 1992
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1. Incorrect installation of components.2. Fitting of wrong parts.
3. Electrical wiring discrepancies.
4. Loose objects left in aircraft.5. Inadequate lubrication.
6.Access panels/fairings/cowlings notsecured.
7. Fuel/oil caps and fuel panels not secured.
8. Gear pins not removed before departure.
UK Flight Safety Committee 2004Top 10 Causes of Maintenance Mishaps
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1. Failure to follow published technical data or local instructions.2. Using an unauthorized procedure not referenced in the
technical data.
3. Supervisors accepting non-use of technical data or failure tofollow maintenance instructions.
4. Failure to document maintenance properly in maintenancerecords, work package.
5. Inattention to detail/complacency.
6. Incorrectly installed hardware on an aircraft/engine.
7. Performing an unauthorized modification to the aircraft.8. Failure to conduct a tool inventory after task completion.
9. Personnel not trained or certified to perform the task.
10. Ground support equipment improperly positioned for the task.
Why Are Technicians Such a ValuableAsset in Reducing Mx Errors/Violations?
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Error Models and
Theories
Error Theories
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Now we will focus on the theoriesof error.
Reasons Swiss Cheese modelMEDA contributing factors model.
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Reasons Swiss
Cheese Model
Reasons Model of AccidentCausation
Defenses
Functional Tests
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