Download - Human Factors Involved in General Aviation
Number
Nanjing University of Aeronautics and
Astronautics
Graduat ion Thes is
Managing Human Factors in Aircraft
Maintenance
Student
Name Muhammad Umer Ajmal
ID Number 190761209
College 19
Major Aeronautical Engineering
Class 1907612
Advisor Cao YuYuan
June 2011
Nanjing University of Aeronautics and Astronautics
Graduation Thesis Letter of Commitment
Private solemn statement: the whole content of this Graduation Thesis
(Title:Managing Human Factors in Aircraft Maintenance) is made
and the whole results are experimented personally under the guidance of
my faculty advisor. Except the deliberately added remarkable contents,
this graduation thesis is completed with my own knowledge and doesn‟t
involve other thesis written by any other person or group.
Personal‟s signature: Date: 2011-06
(Student ID Number):190761209
Managing Human Factors in Aircraft Maintenance
i
Managing Human Factors in Aircraft Maintenance
Abstract
Global statistics indicate that 80% of aviation accidents are due to human errors with 50% due
to maintenance human factor problems. Current human factor management programs have not
succeeded to the degree desired. Many industries today use performance excellence frameworks
such as the Baldridge National Quality Award framework to improve over-all organizational
effectiveness, organizational culture and personal learning and growth. A survey administered to a
sample population revealed a consistent problem with aviation human factors and the need for a
more integrated framework to manage human factor problems in aviation maintenance.
Keywords: Aviation Accidents; industries; Baldridge National Quality Award; Survey
Managing Human Factors in Aircraft Maintenance
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飞机维修管理人为因素
摘要
统计数据表明,全球 80%的航空事故是由于 50%是由于人为因素问题,维修人为错误。
目前的人力因素管理方案没有成功的程度不满意。许多行业都使用性能,如鲍德里奇国家质
量奖卓越架构框架,提高过所有的组织效能,组织文化和个人的学习和成长。人口管理的抽
样调查显示,一个与航空人为因素相一致的问题,必须采取更需要管理的综合框架航空维修
人为因素的问题。
Managing Human Factors in Aircraft Maintenance
iii
Contents
Abstract .......................................................................................................................................... i
Chapter 1 INTRODUCTION .................................................................................................. 1
1.1 Background of the Problem ............................................................................................... 1
1.2 Definition of Human Factors ............................................................................................. 3
1.2.1 Some definitions of Human Factors....................................................................... 3
1.2.2 ICAO Definitions Relating to Human Factors ....................................................... 4
1.3 Human Factors History ...................................................................................................... 4
1.4 Current Human Factor Programs in Aircraft Maintenance ................................................ 8
1.5 The Cost of Maintenance Error ......................................................................................... 9
1.6 Unique Human Factors issues in Aviation Maintenance ................................................... 9
1.7 Performance Excellence Framework ................................................................................ 11
1.8 Researcher‟s Work Setting and Role ................................................................................ 11
1.9 Statement of Problem ........................................................................................................ 11
1.10 Limitations and Assumptions ........................................................................................ 12
Chapter 2 REVIEW OF RELEVANT LITERATURE AND RESEARCH ................................ 13
2.1 Summary of Relevant Data .............................................................................................. 13
2.1.1 Human Factor Errors in Aircraft Maintenance Statistics ..................................... 13
2.1.2 Current Human Factor Programs in Aircraft Maintenance .................................. 17
2.2 The Dirty Dozen .............................................................................................................. 18
2.3 Aviation Performance Excellence Framework ................................................................ 19
2.4 A Model of accident and incident causation by Australian Transport Safety Bureau ..... 22
2.5 The PEAR Model ............................................................................................................. 23
2.6 The SHELL Model .......................................................................................................... 26
2.6.1 Elements ............................................................................................................... 26
2.6.2 SHELL interfaces ............................................................................................. 27
2.7 Statement of Research Question ...................................................................................... 28
Chapter 3 RESEARCH METHODOLOGY ............................................................................... 29
Managing Human Factors in Aircraft Maintenance
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3.1 Research Design .............................................................................................................. 29
3.2 Research Model ............................................................................................................... 29
3.2.1 Survey Population ................................................................................................ 29
3.2.2 Source of Data ...................................................................................................... 30
3.2.3 Pilot Study ............................................................................................................ 30
3.2.4 The Data Gathering Device .................................................................................. 30
3.2.5 Distribution Method ............................................................................................. 31
3.2.6 Instrument Reliability .......................................................................................... 31
3.2.7 Instrument Validity ............................................................................................... 32
3.2.8 Treatment of Data and Procedures ....................................................................... 32
Chapter 4 RESULTS ................................................................................................................... 33
4.1 Human Factor Programs and Management ..................................................................... 33
4.1.1 Most Common Outcomes of Safety Occurrences ................................................ 34
4.2 Survey Feedback .............................................................................................................. 37
Chapter 5 DISCUSSION ............................................................................................................ 39
5.1 Human Factor Management Program .............................................................................. 39
5.2 Most Common Outcomes of Safety Occurrences ........................................................... 39
5.3 Top HFIM drivers that need reviewing ............................................................................ 40
5.4 Influence of experience on human factor management ................................................... 40
5.4.1 Safety Culture ...................................................................................................... 41
5.4.2 Safety Quality ...................................................................................................... 41
5.4.3 Reasons for Violations ......................................................................................... 41
5.4.4 Percentages........................................................................................................... 41
5.4.5 Types of Violations............................................................................................... 41
5.4.6 Frequency of Violations ....................................................................................... 42
5.4.7 Calling Time-Out ................................................................................................. 42
5.4.8 Analysis of the Problem ....................................................................................... 42
5.4.9 Over-Time (OT) Management ............................................................................. 42
5.4.10 Open Reporting .................................................................................................. 43
Managing Human Factors in Aircraft Maintenance
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Chapter 6 CONCLUSION & RECOMMENDATION ............................................................... 44
6.1 Recommendation ............................................................................................................. 45
References ................................................................................................................................... 50
Acknowledgement ..................................................................................................................... XX
Appendix .................................................................................................................................... XX
Managing Human Factors in Aircraft Maintenance
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Chapter 1 Introduction
1.1 Background of the Problem
Imagine you are a member of an aviation organization, such as the military, and you have just
been told that you will need to work over the weekend because there has been a fleet grounding
issue on your A320 aircraft. You will need to work to get all the aircraft inspected by Monday
morning. You have just put in close to 60 hours of work that week and you are really tired. Your
organization has sent you for Human Factors (HF) training and workshops and your management
has told you to call for time-out when you feel tired yet they say there is an urgent need to get the
aircraft inspected over the weekend. Although your body tells you that you can no longer take it,
your mind tells you that you must keep going and be a team player or else the whole team will fail
in this important mission. As you console yourself on your way home, you are reminded of how
many times this year you have been doing this and the close encounters you have had with making
an error of judgment. You are immediately reminded of that famous lecture you heard during HF
training that “the chain is only as strong as its weakest link.” The next morning, before you go to
work, you hear that one of your friends the night before had hit and damaged the aircraft nose
landing gear with a Harlan tractor and now management has called for an urgent safety briefing to
remind everyone of the need to be vigilant and aware of such lapses in judgment. You immediately
recall how one of your colleagues had been screaming to remove the Harlan tractor or Toyota
tractor because they both had exactly the opposite reverse gears, in one you push the lever forward
and the other backward.
Today, more than ever, the aviation world is faced with the constant challenge of addressing
human factors in maintenance. While there have been several advances to the study and
implementation of human factors programs, there are still several inconsistencies to the way these
programs are implemented and hence the varied results.
Aircraft maintenance work encompasses fast turnaround, high pressure with possibly hundreds
of tasks being performed by large numbers of personnel on highly complex and technologically
advanced systems in a confined area. It is very easy for information and tasks to fall through the
Managing Human Factors in Aircraft Maintenance
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safety net. Events around the world in the late 1970s, 1980s and early 1990s, involving crashes or
serious accidents with aircraft, alerted the aviation world to the fact that although the aircraft were
becoming much more reliable, the human being in the process had the potential to obliterate any of
these technological advances. The role played by human performance can be found below.
Figure 1.1 The role played by human performance in civil aircraft accidents. (IATA, 1975)
In this research project we will analyze the top human factor problems in aviation maintenance
and evaluate a holistic solution to addressing these problems through a performance excellence
framework. We will start with a brief look at the history of HF programs and the changes that have
taken place over the years. We will also explore the current HF programs adopted by several
organizations and try to understand why HF error occur, and how comprehensive, the solutions
currently adopted. Then finally, we will look at the Baldridge national quality program and criteria
for performance excellence to see if we can formulate a more comprehensive solution to managing
HF in maintenance. In essence, we would be looking at a more systemic solution to HF
management as HF is more than just about people.
Managing Human Factors in Aircraft Maintenance
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1.2 Definition of Human Factors
Human Factors as a term has to be clearly defined because when these words are used in the
vernacular they are often applied to any factor related to humans. The human element is the most
flexible, adaptable and valuable part of the aviation system, but it is also the most vulnerable to
influences which can adversely affect its performance. Throughout the years, some three out of four
accidents have resulted from less than optimum human performance. This has commonly been
classified as human error.
The term “human error” can be misleading when referring to human factors in accident
prevention, because although it may indicate WHERE in the system a breakdown occurs, it
provides no guidance as to WHY it occurs. An error attributed to humans in the system may have
been design-induced or stimulated by inadequate training, badly designed procedures or the poor
concept or layout of manuals. Further, the term “human error” allows concealment of the
underlying factors which must be brought to the fore if accidents are to be prevented. In fact,
contemporary safety thinking argues that human error should be the starting point rather than the
stop-rule in accident investigation and prevention.
An understanding of the predictable human capabilities and limitations and the application of
this understanding are the primary concerns of Human Factors. Human Factors has been
progressively developed, refined and institutionalized for many decades, and is now backed by a
vast store of knowledge which can be used by those concerned with enhancing the safety of the
complex system which is today‟s civil aviation.
1.2.1 Some definitions of Human Factors
Human Factors is concerned to optimize the relationship between people and their activities,
by the systematic application of human sciences, integrated within the framework of systems
engineering [1]
.
Human Factors refers to the study of human capabilities and limitations in the workplace.
Human Factors include, but are not limited to, such attributes as human physiology, psychology,
work place design, environmental conditions, human-machine interface, and more. Human Factors
researchers study system performance. That is, they study the interaction of humans, the equipment
Managing Human Factors in Aircraft Maintenance
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they use, the written and verbal procedures and rules they follow, and the environmental conditions
of any system [2]
.
Human Factors and ergonomics and engineering psychology are roughly equivalent terms used
for the field of science concerned with the optimization of the relationship between people and the
machines they operate through the systematic application of human sciences integrated within the
framework of systems engineering. Human Factors has been more widely used in the USA,
ergonomics has been more widely used outside of the USA, and engineering psychology has been
more widely used in academia [3]
.
1.2.2 ICAO Definitions Relating to Human Factors
Human Factors Principles: Principles which apply to aeronautical design, certification, training,
operations and maintenance and which seek safe interface between the human and other system
components by proper consideration to human performance [4]
.
Human performance: Human capabilities and limitations which have an impact on the safety
and efficiency of aeronautical operations [5]
.
Human factors are essentially a multi-disciplinary field, including but not limited to:
psychology, engineering, physiology, sociology and anthropometry [6]
.
Aviation Human factors are primarily oriented towards solving practical problems in the real
world. As a concept, its relationship to the human sciences might well be likened to that of
engineering to the physical sciences. And, just as technology links the physical sciences to various
engineering applications, there are a growing number of integrated Human Factors techniques or
methods; these varied and developing techniques can be applied to problems as diverse as accident
investigation and the optimization of pilot training [7]
.
1.3 Human Factors History
In the late 1970s, Cockpit Resource Management (CRM) featured prominently in pilot training.
The term was used to apply to the process of training flight crews to reduce pilot error by making
better use of the resources on the flight deck. A change in name was made from Cockpit to Crew
Resource Management to change the emphasis of training to focus on cockpit group dynamics.
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Some airline programs dealt with specific topics such as team building, briefing strategies,
situational awareness and stress management. In the early 1990s, CRM training began to reflect the
many factors, such as organizational culture, within the aviation system in which the crew must
function which can determine safety.
Similarly, but much later, it was not until in the 90s that Maintenance Resource Management
(MRM) was made available to maintenance personnel. After years of accidents, many caused by HF
errors, nothing significant was really done to determine the HF root causes. Unlike CRM, MRM
was very new to the aviation maintainers and it was not until June 10, 1990 when a cockpit window
blew out at 16,000 feet, and a pilot almost went with it, that an in depth look at the contributing
factors to a maintenance error were examined . David King, from the United Kingdom is one of the
first to look at HF in the same light it is looked at today.
Figure 1.2 Human Factors History, the 12th
ICAO Symposium on Human Factors in Aviation Maintenance.
The need for a change in approach to human errors and their reporting was reinforced during
the CAA sponsored 12 Symposium on Human Factors in Aviation Maintenance that was held in
Gatwick Airport, England, on 10-12 March 1998. It was the first of the international symposiums
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involving the CAA, FAA and Transport Canada. The foundation of Human Factors training as a
modern aviation tool was probably initiated in the United States at a workshop sponsored by the
National Aeronautics and Space Administration (NASA) in 1979. This workshop was the
development of NASA research into the causes of air transport accidents. The International Civil
Aviation Organization, (ICAO) now requires organizations to include HFIM training. HF training
which helps our fellow maintenance personnel to avoid an error he/she never intends to make had
finally arrived.
The approach to understanding and applying human factors can be simplified using a model.
The SHEL model, developed in the „60s by E. Edwards, may be the most common model discussed
in aviation human factors circles. However, this author suggests an easier to understand model
developed by Dr. Michael Maddox for a maintenance human factors course that we offer. The
PEAR model is a means to consider human factors within any organization or context. As we
consider the past, present, and future direction of human factors, the PEAR works.
By 1910, the U.S. Army was conducting pilot selection and accident investigations based on
pilot medical factors. Therefore, it is the field of medicine that may deserve the claim to the first
formal study of human factors in aviation. Of course, it can also be reasonably argued that inventors
from Leonardo DaVinci to the Wright Brothers considered all items in the PEAR model. Icarus,
unfortunately, failed to consider Environment during any human factors analysis he may have
conducted.
Military aircraft production drove much of the early consideration of human factors. During
the „40s military aircraft were in heavy production throughout the world, driven by WWII.
Investigations during the war lead to the conclusion that cockpit design was a problem. The original
design, and between-model modifications to displays and controls, caused the pilot to commit errors.
The term “engineering psychology” emerged in the „40s with the focus on designing aircraft with
an improved match to the capabilities and limitations of humans. At a minimum, the early
engineering psychologists had to ensure standardization of displays and controls (a.k.a., knobs)
within and between aircraft types. The attention to knobs and dials, by the way, resulted in the
somewhat humorous term “knobology,” which is indeed a small and ongoing subset of human
factors.
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In the late „40s and „50s, professional societies of human factors engineers and psychologists
formed the Ergonomics Research Society (1949 in the U.K.) and the Human Factors Society (1957
in the U.S.) In 1995 the Human Factors Society evolved to the Human Factors & Ergonomics
(HF&E) Society, thus encompassing all physical, physiological, and cognitive aspects of the human
in any given system. Today the HF & E Society has over 5,000 active members throughout the
world.
Maintenance human factors began receiving attention in the early „50s at Wright Air Force
Base in Ohio. Researchers there focused on such aspects as selection and training of maintenance
personnel. Even then researchers were lamenting the growing complexity of aircraft and the
associated electronics equipment!
Human factors research evolved substantially from the „60s through the „80s. Manned space
flight research made significant contributions to formal studies of the human in the system. While
the PEAR model was not formally used all aspects of PEAR were applicable. The design of the
complex fighter jets introduced increasingly complex aircraft and weapon systems that could easily
overload human processing capability. The importance of the situation awareness was highlighted,
not only by the military aircraft, but also by a few famous commercial incidents and accidents. In
other industries, such as nuclear power electric generation, many examples of human error taught us
that humans sometimes did not fully understand the complex systems that they were “controlling.”
Critical incidents like the aircraft accidents at Tennerife (1977), the United DC8 fuel
exhaustion accident off the Oregon coast (1978), and the nuclear plant Three Mile Island (1979)
focused considerable attention on the study of human factors, such as training, communication,
procedures, situation awareness, and crew resource management. Research, development, and
products have evolved as a result of these accidents.
In 1988 the Aloha Airlines 737 encountered the famous “convertible aircraft” phenomenon.
This accident placed focus on the aging aircraft fleet, but just as much attention was focused on
maintenance human factors. The Aloha Accident report identified numerous human factors issues
including, but not limited to, training, use of procedures, and use of a manufacturer‟s service
bulletins.
In 1988 the U. S. Congress passed the Aviation Safety Research Act (PL 100-592). Within that
Managing Human Factors in Aircraft Maintenance
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law was the expressed intent to study all aspects of human factors in aviation safety including
human factors in maintenance. That Act, and the associated ongoing funding, without doubt, has
had the single greatest impact on the current international airline and government attention to
human factors in airline maintenance. Since 1988, the FAA Office of Aviation Medicine has
invested an average of $1.25M per year on maintenance human factors research and development.
The FAA R&D has been matched by considerable aviation industry services and participation
in-kind. The success story of the research program constitutes the next subsection of this paper.
1.4 Current Human Factor Programs in Aircraft Maintenance
MRM which later evolved into Human Factors in Maintenance (HFIM) was developed to
provide primarily the training required to understand and prevent HF errors from occurring. The
main breakthrough that was achieved in recent years is the emphasis given by senior management
in organizations to HF programs. Many consultants and companies have enjoyed this upward focus
on HF. Gordon Dupont, formerly of Transport Canada, is one such consultant whose excellent
“Dirty Dozen” classification of HF root causes has been widely adopted by several aviation
organizations. Other organizations like Boeing have developed their own in-house Maintenance
Error and Decision Analysis (MEDA) programs with more in depth analysis including the
background of personnel that commit these HF errors to better understand the extent of solutions
necessary. Most of these programs are designed to identify the HF errors, educate the personnel on
their causal potential, suggest ways to contain and correct the problem and create a HF error-free
environment. While many of these programs have truly made the aviation work environment safer,
many of them still look at HF from a „people‟ perspective rather than “an organization” perspective.
There may be a need to develop programs that improve the performance of all areas of an
organization as a whole which will provide long term solutions to HFIM.
1.5 The Cost of Maintenance Error
Since the end of World War II, human factors researchers have studied pilots and the tasks they
perform, as well as air traffic control and cabin safety issues. Yet until recently, maintenance
Managing Human Factors in Aircraft Maintenance
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personnel were overlooked by the human factors profession. Whatever the reason for this, it is not
because maintenance is insignificant. Maintenance is one of the largest costs facing airlines. It has
been estimated that for every hour of flight, 12 man-hours of maintenance occur. Most significantly,
maintenance errors can have grave implications for flight safety.
Accident statistics for the worldwide commercial jet transport industry show maintenance as
the „primary cause factor‟ in a relatively low four per cent of hull loss accidents, compared with
flight crew actions that are implicated as a primary cause factor in more than 60 per cent of
accidents. Yet primary cause statistics may tend to understate the significance of maintenance as a
contributing factor in accidents. In 2003, Flight International reported that technical and
maintenance failure emerged as the leading cause of airline accidents and fatalities, surpassing
controlled flight into terrain, which had previously been the predominant cause of airline accidents.
According to former NTSB Board member John Goglia, deficient maintenance has been implicated
in 7 of 14 recent airline accidents.
Maintenance errors not only pose a threat to flight safety, but can also impose significant
financial costs through delays, cancellations, diversions, and other schedule disruptions. For
example, in the case of a large aircraft such as a Boeing 747-400, a flight cancellation can cost the
airline around USD $140,000, while a delay at the gate can cost an average of USD $17,000 per
hour. In this context it can be seen that even simple errors such as gear pins left in place, requiring a
return to gate, can involve significant costs. Even a small reduction in the frequency of
maintenance-induced schedule disruptions can result in major savings.
1.6 Unique Human Factors issues in Aviation Maintenance
Maintenance personnel are confronted with a set of human factors unique within aviation.
Maintenance technicians work in an environment that is more hazardous than most other jobs in the
labor force. The work may be carried out at heights, in confined spaces, in numbing cold or
sweltering heat. The work can be physically strenuous, yet it requires clerical skills and attention to
detail. Maintenance technicians commonly spend more time preparing for a task than actually
carrying it out. Dealing with documentation is a key activity, and maintenance engineers typically
Managing Human Factors in Aircraft Maintenance
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spend nearly as much time wielding a pen as they do holding a screwdriver. The work requires good
communication and coordination, yet verbal communication can be difficult due to noise levels and
the use of hearing protection. The work frequently involves fault diagnosis and problem solving in
the presence of time pressures, particularly at the gate.
Maintenance personnel also face unique sources of stress. Air traffic controllers and pilots can
leave work at the end of the day knowing that the day‟s work is complete. In most cases, any errors
they made during their shift will have either had an immediate impact or no impact at all. In
contrast, when maintenance personnel leave work at the end of their shift, they know that the work
they performed will be relied on by crew and passengers for months or years into the future. The
emotional burden on maintenance personnel whose work has been involved in accidents is largely
unrecognized outside the maintenance fraternity. On more than one occasion, maintenance
personnel have taken their own lives following aircraft accidents caused by maintenance error.
From a human factors perspective, maintenance personnel have more in common with doctors
than with pilots. We know from medicine that iatrogenic, or doctor caused, injury can be a
significant threat to patient health. Medical errors include surgical instruments sewn up inside
patients, disorders being misdiagnosed, and very occasionally, surgeons operating on the wrong
limb. Most aircraft maintenance personnel will be familiar with these types of errors. Opening up a
healthy patient at regular intervals to check that organs are functioning normally would not be an
appropriate strategy in health care, yet preventative maintenance in aviation often requires us to
disassemble and inspect normally functioning systems, with the attendant risk of error.
Just as medicine can be about preventing or responding to a condition, so maintenance can be
divided into two categories. These are scheduled and unscheduled maintenance. The distinction
between these two categories has significant implications for maintenance human factors.
Scheduled maintenance tasks are typically preventative. Many preventative tasks are
performed regularly, and so are familiar routines for maintenance personnel. Experienced personnel
will be unlikely to make mistakes related to a lack of knowledge or skills on a familiar preventative
task. Maintenance discrepancies on familiar tasks are more likely to involve breakdowns in
teamwork; everyday „absent minded‟ mistakes such as forgetting to install components, and action
slips where a person absent-mindedly performs a routine action that they had not intended to
Managing Human Factors in Aircraft Maintenance
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perform.
Unscheduled tasks are usually corrective in nature, and are performed in response to unplanned
events such as aircraft damage or component failure. Although some unscheduled tasks are minor,
others require extensive system knowledge, problem solving and specialized skills.
1.7 Performance Excellence Framework
Performance Excellence Framework (PEF) has been used in several countries and in several
sectors such as Education, Healthcare, Tourism and Housing. Most recently, the Defense industry
has been using such framework to gauge its quality health. One of the first of such frameworks,
established in 1988, is the Malcom Baldridge National Quality Award (MBNQA) framework which
covers all areas of a business such as Process Management, Information Management, Strategic
Planning, Human Resource Development and the Use of Results [8]
. The key thrust for performance
excellence is to establish a culture of continuous improvement and innovation that builds upon a
strong foundation of quality, professionalism and team excellence always.
1.8 Researcher’s Work Setting and Role
The researcher is a Bachelors student with the major of Aerospace Engineering (Bach 2007) in
Nanjing University of Aeronautics & Astronautics situated in Nanjing, Jiangsu, Peoples Republic of
China. This paper is the graduation thesis of the researcher. In order to complete his bachelors the
researcher chose this topic for his thesis because it is very interesting and has a very wide role and
impact in the field of aviation.
1.9 Statement of Problem
Global statistics indicate that 80% of aviation accidents are due to human errors with 50% due
to maintenance human factor problems. Most programs currently implemented are designed to
identify the HF errors, educate the personnel on their causal potential, suggest ways to contain and
correct the problem and create a HF error-free environment. However, the percentage of HF errors
in aviation mishaps is on the rise today. There is a need for a more integrated and holistic approach
Managing Human Factors in Aircraft Maintenance
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to HF management.
1.10 Limitations and Assumptions
Due to the limited time and access to a limited area of the aviation industry, the researcher was
limited to survey just the students and professors of the university and only a handful of people who
are holding jobs in some aviation industry. Due to lack of time and access the researcher was forced
to find details and previously done research on the respected topic and also had to make some
assumptions on the way.
Managing Human Factors in Aircraft Maintenance
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CHAPTER 2 Review of Relevant Literature and Research
2.1 Summary of Relevant Data
2.1.1 Human Factor Errors in Aircraft Maintenance Statistics
In the United Kingdom (UK) between 1982 and 1991, there were 1,270 Mandatory Occurrence
Reports (MOR) which involved maintenance errors submitted to the CAA Safety Data Department
(CAA, 1992). Of these, only 230 resulted in an unexpected or undesirable occurrence that interrupts
normal operating procedures that may cause an accident or incident. The CAA concluded that there
was no significant risk to the public. In the period 1992-1994, however, there were 230 MORs and
in 1995 to 1996 there were 534. The number of reported errors was occurring at a greater frequency.
Similarly a study by Boeing in 1993 of 122 occurrences between 1989- 1991 revealed that 56% of
human factors errors resulted in omissions with a further 30% resulting in incorrect installations.
In a field test by Boeing in 1994 to 1995 with nine maintenance organizations, the main types,
causes and results of errors are summarized below in table 2.1.
Table 2.1 Boeing field test with MEDA
In 1998, the Australian Transport Safety Bureau (Hobbs & Williamson, 1998) surveyed close
to 1400 Licensed Aircraft Maintenance Engineers (LAMEs). The most common outcomes for
airline related maintenance occurrences were:
1. Systems operated unsafely during maintenance
2. Towing events
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3. Incomplete installation
The most common outcomes of non-airline occurrences were:
1. Incorrect assembly or orientation
2. Incomplete installation
3. Persons contacting hazards
The most common causes to these unsafe acts are summarized below in table 2.2.
Table 2.2 1997 Survey by Australian Transportation Safety Bureau
A ground crew attitude survey in the military in Asia (classified source, n.d) revealed similar
findings to that of the Australian Transport and Safety Board. The surveys were conducted
bi-annually from 1999 to 2003 on approximately 2500 aviation technicians. In the survey conducted
in 1999, the top three violations were:
1. Servicing without a checklist
2. Speeding
3. Omitting job steps
Approximately 20% of those surveyed disclosed that they would violate rules daily or once a
week. The top three reasons for these violations were:
1. Too much work, too little time
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2. Insufficient manpower
3. Time pressure to complete duties
In 2003, when the survey was conducted again, several key initiatives had been implemented
to address HFIM such as:
1. Implementing a Human Factor training program initiated by Mr. Gordon Dupont, Chief
Executive Officer (CEO), and System Safety Services in 1999.
2. Training 100% of the licensed aircraft engineers in Human Factors Management.
3. Implementing a MEDA type Human Error Analysis Tool (HEAT).
4. Embracing a local version of the Malcom Baldridge Performance Excellence Framework for the
military over six years from 1998.
5. Embracing additional performance excellence measurement tools such as the Balanced Score
Card and Enhanced Value Organization principles.
The survey results comparison between 1999 and 2003 revealed the following significant
improvements which is show below in table 2.3.
Table 2.3 Asian Study survey comparison between 1999 and 2003
Survey Coverage Results
Safety Culture (new)
99% agreed that the organization placed strong
emphasis on safety and quality. Personnel also
agreed that management (96.43%), supervisors
(97.30%) and personnel (94.38%) showed strong
emphasis and take safety / quality seriously.
Reasons for Violations
Top 4 reasons remain unchanged. “Easy way out
(Taking short cuts)”, which registered an
increase of 11% (13% to 24%), has emerged as
the 5th reason. "Lack of proper tools", the 6th
reason, registered a significant increase of 14%
(7% to 21%).
Types of Violations Overall reduction of 4% (14% to 10%) was
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noted for the 6 common types of violations
observed everyday and once a week.
Frequency of Violations Improvements of 22% (21% to 43%) that
violations observed were “very infrequent.”
Calling Timeout Reduction by 11% (50% to 39%) in holding
back to call timeout.
Overtime Management Reduction by 16% (49% to 33%) in frequency
(weekly) of overtime.
Open Reporting Culture
Improvement of 16% (66% to 82%) that open
reporting is being practiced widely in the
organization.
Safety / Quality
Information
Dissemination
98% (an improvement of 8%) agreed that
Safety/Quality information is readily available.
Management are also conducting briefings and
disseminating safety/quality information more
frequently, matching closely to that desired in
the previous survey.
Several UK maintenance organizations have pooled their Maintenance Error Management
System (MEMS) data, using a common MEDA taxonomy. The initial results were presented at a
MEMS-MEDA seminar in the UK in May 2003, a selection of which is listed below in table 2.4.
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Table 2.4 Several UK Maintenance Error Management System (MEMS) data.
The maintenance error trends in US, Australia, Asia and United Kingdom from 1982 to 2003
are alarmingly similar and they continue to plague the aviation industry and in some areas of
aviation such as in the military. The trends in maintenance human factor errors have continued to
increase. A closer look at the statistics indicates that these trends are due mainly to lapses in the
organizational operational culture and business processes. Time pressure seems to be the main
factor due to lack of manpower and excess workload. In recent years, HF training has focused on
these lapses in rules and the detrimental consequences of such actions. There is still an uptrend of
these maintenance errors and violations in the aviation maintenance field.
2.1.2 Current Human Factor Programs in Aircraft Maintenance
Several HFIM courses have evolved since ICAO required HFIM training which include those
by the UK CAA, FAA as well as JAR compliant courses to ensure consistency and conformance to
minimum standards set out by the governing bodies. A typical HFIM course such as the one
developed to comply with JAR145-12 includes:
1. A General introduction to Human Factors
2. Safety Culture/Organizational factors overview
3. Human Performance, limitations and Human Error models
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4. Environmental issues impacting Human Performance
5. Procedures, Information, Tools and Practices
6. Professionalism, Integrity, Communication and Teamwork
7. Organization HF program including the management of HF errors
2.2 The Dirty Dozen
Gordon Dupont, formerly from Transport Canada, now CEO of System Safety Services, is a
renowned human factors proponent and conducts several of his HPIM courses all around the world
in the aviation sectors. He is best known for his “Dirty Dozen” [9]
posters which depict the most
common 12 human factor errors in maintenance. Some dirty dozen posters are shown in figure 2.1
below.
Figure 2.1 “The dirty dozen” posters from Gordon Dupont, System Safety Services.
Names of the “dirty dozen” 12 points:
1. Complacency
2. Distraction
3. Fatigue
4. Norms
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5. Pressure
6. Stress
7. Lack of Assertiveness
8. Lack of Awareness
9. Lack of Communication
10. Lack of Knowledge
11. Lack of Resources
12. Lack of Teamwork
Gordon conducts three workshops, HPIM Part One to Part Three, and covers areas such as the
background to HFIM behaviors and errors through case studies, organizational culture and risk
management and ways to manage them.
As can be seen from the typical course structures above, current HFIM courses generally adopt
the three E‟s or Educate personnel, Equip personnel with the tools necessary to contain, correct and
prevent HF errors and Evaluate the management of HFIM programs. This in essence is the main
coverage for most HFIM courses and programs adopted by commercial airline and other aviation
industries.
Professor James Reason and his “Swiss Cheese” model propounds that there are several latent
conditions prior to an active failure or unsafe act. These failed or absent defenses line up to cause a
mishap or injury waiting to happen. Interestingly, one of the first lapses in defenses in his model
starts at organizational influences as can be seen from the model below. Gordon Dupont, CEO,
System Safety Services modified James Reason‟s “Swiss Cheese model” incorporating his famous
“Dirty Dozen” human error factors as the preconditions to unsafe acts which could eventually cause
an accident/incident. Gordon attributes 70% of accident causation to fallible decisions by
management, deficiencies in line management and the preconditions which are the “Dirty Dozen”
human error factors.
2.3 Aviation Performance Excellence Framework
More than 66 business excellence awards in 43 countries have been established adopting
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similar frameworks to the MBNQA framework. One of the many objectives of this framework is to
create the values desired by businesses and customers and build a system which can sustain a
competitive edge for an extended period of time. Most of these performance excellence frameworks
have seven main criteria areas namely:
1. Leadership
2. Strategic Planning
3. Measurement, Analysis and Knowledge Management
4. Human Resource Focus
5. Process Management
6. Customer and Market Focus
7. Business Results
Figure 2.3 explains these criteria systematically.
Figure 2.3 MBNQA Criteria for Performance Excellence Framework one
One of the main objectives of the framework criteria is to motivate an organization into
creating strategies, systems and methods of achieving excellence, stimulating innovation and
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building knowledge and capabilities. Achieving the highest levels of business performance requires
a well-executed approach to organizational and personal learning. This will result in not only better
products but also move toward being more responsive, adaptive, innovative and efficient thus
giving an organization marketplace sustainability and performance advantages while it gives
employees the satisfaction and motivation to excel [10]
.
Today, the main focus in many businesses is the relentless pursuit for innovation. Innovation
means making meaningful change to improve an organization‟s products, services and processes
and to create a new value for the organization. Organizations should be led and managed so that
innovation becomes part and parcel of the learning culture and is integrated into daily work. The
use of a balanced composite of leading and lagging performance indicators measures the effective
means to communicate short and long term priorities. It also helps monitor performance and
provides a clear basis for improving results. The adoption of this framework constitutes a systemic
approach to managing an organization and is proposed in this paper as a necessary means for
reducing significantly aviation‟s “Dirty Dozen” maintenance human factor issues.
Several defense related organizations have adopted this framework and tailored it to their needs.
Some of the key realigned objectives from the framework can be found below. The MBNQA
framework has been adopted by many sectors in the industry namely health, education and most
recently in the defense industry in Asia over the last 10 years. The framework provides excellent
criteria for organizations to follow to permeate a culture of excellence. Most relevant for the
defense industry, and to human factor management, are the four main areas of the framework
namely:
1. Leadership and Organizational Culture
2. Measurement, Analysis and Knowledge Management
3. Human Resource Focus
4. Process Management
The key objectives for the Malcom Baldridge National Quality Award framework for
performance excellence can be translated to key objectives for a successful Human Factor program.
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2.4 A Model of accident and incident causation by Australian Transport Safety
Bureau
The errors of maintenance personnel can be the most visible aspects of maintenance human
factors, but to understand how and why maintenance errors occur, we need to understand the
organizational context in which they occur. The Figure below shows the main causal elements
involved in accidents and incidents. It is an adaptation of the „Swiss Cheese‟ model originally
developed by James Reason.
According to this model, accidents or incidents are usually triggered by the actions of
operational personnel, such as pilots or maintenance engineers. However, these actions occur in the
context of local conditions, such as communication, workplace conditions, and equipment. The task
environment also includes risk controls. These are features such as procedures, checks or
precautions designed to manage hazards that threaten safety. Risk controls, local conditions and
individual actions can, in turn, be influenced by organizational factors such as company policies,
resource allocation, and management decisions.
In order to understand and ultimately prevent accidents, it is necessary to trace the chain of
causes back through all the elements of the system including organizational influences. This is often
referred to as root cause analysis. The model is shown in figure 2.4.
Figure 2.4 A model of accident and incident causation
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Individual Actions
Human error is a threat to virtually all advanced technological systems. It has been estimated
that human error is involved in 70 per cent of aircraft accidents, as well as 80 per cent of shipping
accidents, and at least 58 per cent of medical misadventures.15 According to some authorities,
around 80,000 people in the US die each year because of avoidable medical errors.16 So it should
not be surprising to learn that human error is a significant threat in airline maintenance.
The use of the term „human error‟ should not imply that we have a problem with people. In
many cases, maintenance errors are symptoms of underlying problems within the organization.
Although they are unwanted events, errors are valuable opportunities to identify improvements.
There are two main approaches to describing errors: physical descriptions and psychological
descriptions.
2.5 The PEAR Model
For over a decade, the term “PEAR” has been used as memory jogger, to characterize human
factors in aviation maintenance. PEAR prompts recall of the four important considerations for
human factors programs: People who do the job, the Environment in which they work, the Actions
they perform, and the Resources necessary to complete the job. The Aircraft Electronics
Association (AEA) acknowledges that PEAR is an excellent way to remember key considerations
for a human factors program.
A maintenance human factors program does not have to be complex, expensive, or a burden to
the organization. A human factors program will help minimize errors and complement the design
of a safety management system (SMS). There are plenty of excellent resources to help you tailor a
program for your organization.
For nearly 20 years, the Federal Aviation Administration (FAA) has provided extensive
information on human factors. More recently, the European Aviation Safety Authority (EASA) and
Transport Canada have also published human factors information. A recent Google search of the
term “maintenance human factors” delivered 11,300 hits. The real challenge is convert the vast
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amount of information into understandable and practical solutions for your organization.
The memory jogger PEAR makes the recognition and mitigation of human factors even easier. It
stands for:
1. People who do the job
2. Environment in which they work
3. Actions they perform
4. Resources necessary to complete a job
This article will consider these four topics and their relevance to human factors and safety
management systems.
People
Aviation maintenance human factors programs focus on the people who perform the work, and
address physical, physiological, psychological, and psychosocial factors. It must focus on
individuals, their physical capabilities, and the factors that affect them. It should also consider
their mental state, cognitive capacity, and conditions that may affect their interaction with others.
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Environment – Physical and Organizational
There are at least two environments in aviation maintenance. There is the physical workplace
on the ramp, in the hangar, or in the shop. There is also the organizational environment that exists
within the company. A human factors program must pay attention to both environments.
The physical environment is obvious. It includes ranges of temperature, humidity, lighting,
noise control, cleanliness, and workplace design. Companies must acknowledge these conditions
and cooperate with the workforce to either accommodate or change the physical environment. It
takes a corporate commitment to address the physical environment.
The second, less tangible, environment is the organizational one. The important factors in an
organizational environment are typically related to cooperation, communication, shared values,
mutual respect, and the culture of the company. An excellent organizational environment is
promoted with leadership, communication, and shared goals associated with safety, profitability,
and other key factors.
Actions
Successful human factors programs carefully analyze all the actions people must perform to
complete a job efficiently and safely. Job task analysis (JTA) is the standard human factors
approach to identify the knowledge, skills, and attitudes that are necessary to perform each task in a
given job. The JTA helps identify what instructions, tools, and other resources are necessary.
Adherence to the JTA helps ensure that each worker is properly trained and that each workplace has
the necessary equipment and other resources to perform the job. Many regulatory authorities
require that the JTA serve as the basis for the company‟s general maintenance manual and training
plan.
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Resources
The final PEAR letter is “R” for Resources. Again, it is sometimes difficult to separate
Resources from the other elements of PEAR. In general, the characteristics of the People,
Environment, and Actions dictate the Resources. Many resources are tangible, such as lifts, tools,
test equipment, computers, technical manuals, and so forth. Other resources are less tangible.
Examples are the number and qualifications of staff to complete a job, the amount of time allocated,
and the level of communication among the crew, supervisors, vendors, and others.
2.6 The SHELL Model
The SHELL Model is defined as “the relationship of human factors and the aviation
environment. This concept has originated from the „SHEL Model‟ by Edwards in 1972, which the
name was derived from the initials of its components (Software, Hardware, Environment, and
Liveware). In 1975, Hawkins developed the concept into the „SHELL Model‟ with an introduction
of another Liveware into the original concept, „SHEL Model‟.
2.6.1 Elements
The main elements in the model can be listed as follows:
Hardware
Various equipments, tools, aircraft, workspace, buildings and other physical resources without
human elements in aviation constitute the Hardware.
Software
The Software comprehends all non-physical resources, which are for organically operation,
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like organizational policies/rules, procedures, manuals and placards.
Environment
The Environment includes not only the factors which influence where people are working such
as climate, temperature, vibration and noise, but also socio-political and economic factors.
Liveware
The Liveware includes factors like teamwork, communication, leadership and norms.
Central Liveware
The Liveware, which is in the centre of the SHELL Model, can be defined as human elements
such as knowledge, attitudes, cultures and stress. This Liveware is regarded as the core of the
SHELL Model and other components match with the Liveware as the central figure.
2.6.2 SHELL interfaces
L-H System
Firstly, the interaction between the Liveware and the Hardware (L-H system) is usually named
man-machine system. This system can be easily explained by an example which aircrafts should
provide a great value of services as much as they can, such as fitting seat in aircraft, for the
passenger‟s comfortable flight.
L-S System
The second interface, in the SHELL Model, is represented as the interaction between the
Liveware and Software. As the Software indicates intangible objects than those of the Hardware, it
is clear that the error of L-S interaction is more difficult to solve than the error of L-H interaction.
L-E System
The efforts toward the error of this L-E interaction is well shown from flight instruments,
which help overcome obstacles of flight, like helmet against the noise, flying suit against the cold,
goggles against the effects of altitude.
L-L System
Finally, there is the last interface in the SHELL Model, which is the interaction between the Liveware and
Liveware. This L-L interface is also related to leadership, crew cooperation and personality interaction and human
factors experts have ascertained that, the problems of L-L interaction, such as errors within team-work, had caused
a great deal of accidents.
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2.7 Statement of Research Question
Since the dawn of aviation, the aviation maintenance community has been constantly
motivated to reduce human factor errors and its operational/organizational impact. Most programs
currently implemented are designed to identify the HF errors, educate the personnel on their causal
potential, suggest ways to contain and correct the problem and create a HF error-free environment.
While many of these programs have truly made the aviation work environment safer, human factor
errors still continue to persist today. There is a need for a more integrated and holistic approach to
human factor management.
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Chapter 3 Research Methodology
3.1 Research Design
The research design used for this study was the self-report descriptive research method. A
quantitative descriptive approach will be used to collect and assess the data. Survey results were the
sole source of data collection for this study.
3.2 Research Model
The researcher has collected a wealth of HFIM data and results from organizations in Asia,
Australia and the United States to understand the current state of HFIM and the initiatives currently
implemented. The researcher used a survey that will be e-mailed to 25 OO-ALC/YPX Senior
National Representatives (SNR) representing close to 18 countries with military ranks ranging from
Major to Brigadier General at Hill AFB. The survey was administered to ascertain the effectiveness
of human factor management through various programs and initiatives adopted.
3.2.1 Survey Population
The survey population for this study is 25 People. The survey was done in complete
confidentiality and with the consent of the personnel involved in the survey. Out of the 25 people
surveyed 15 were students of aerospace engineering, 5 were senior professors and 5 were
employees of some aviation organization which they wish to be remained undisclosed. The survey
demographics are listed in table 3.1
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Table 3.1 Survey Demography
Overall
Participation of Personnel
Total (R) 25
Total Participants (TP) 25
Participation Rate (%) 100 %
No. of Students 15
No. of Professors 5
No. of Aviation Industry Employees 5
3.2.2 Source of Data
The sources of data was a combination of completed research from organizations such as
NTSB, FAA, Boeing and civil aviation organizations that is available on the internet as well as a
data collection device in the form of a survey.
3.2.3 Pilot Study
A pilot survey was presented to the researcher‟s Nanjing University of Aeronautics &
Astronautics Bach 2007 classmates. The survey sample for this study was 15 personnel with varied
background majors such as maintenance, administration and contracts. Invaluable feedback was
given by the classmates on the researcher‟s use of terms, flow of questions in the questionnaire as
well as the clarity of certain feedback surveyed.
3.2.4 The Data Gathering Device
The data gathering device used in this study was a researcher designed survey. The survey
included questions to determine the engineering field, job description (If Any), total length of job
experience (If Any), HFIM awareness and nine questions designed to determine the implementation
and effectiveness of HFIM programs. The researcher consulted the opinion of several renowned
HFIM activists and organizations on the details of questions in the survey.
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Table 3.2 Survey coverage and objectives
3.2.5 Distribution Method
The HF survey was written as a word document and e-mailed to the personnel who agreed to
be a part of this research. The researcher met with the personnel involved personally prior to
sending out the survey so as to notify them of such an effort. The researcher also met with them to
go through the survey and clarify each question as required. The researcher also took the
opportunity to gather personal feedback from senior officers in some airlines on their experiences
with human factor issues. The people surveyed were given one week to review the questions. All
responses were collected back by the researcher at a stipulated time.
3.2.6 Instrument Reliability
This researcher‟s Nanjing University of Aeronautics & Astronautics Bach 2007 classmates
conducted a peer review of the HFIM management Survey which gave the researcher good
feedback on the reliability of the survey. Upon completion of the survey on these personnel, the
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researcher conducted a stability or test-retest reliability analysis.
3.2.7 Instrument Validity
This researcher‟s Nanjing University of Aeronautics & Astronautics Bach 2007 classmates
conducted a peer review of the HFIM management Survey. Additionally, the researcher consulted
several experts in the field of Human Factor management such as those from the University‟s
aircraft maintenance department and human resources office, on the survey structure and contents.
Each question was reviewed to evaluate the relevancy to the purpose. The results of the survey were
collected, and the researcher was able to validate the accuracy of the measurement instrument.
3.2.8 Treatment of Data and Procedures
Because the researcher surveyed two groups of people, namely those with only the knowledge
of extensive maintenance and no experience in the relevant field and those with only a few years of
experience, he reviewed the results of the survey by experience level. As the survey population was
too small, the researcher was forced to omit some points raised by some classmates using statistical
analysis. The data gathered from the HFIM management surveys were analyzed to determine the
effectiveness of HFIM programs. The researcher then made conclusions and recommendations
based on the provided data.
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Chapter 4 Results
The results of the Human Factor Management Survey carried out from March 2011 to May
2011 can be found below. Of the survey population, 96% was sampled. The results are broken down
to the four parts of the survey questionnaire. The survey can be found in Appendix.
4.1 Human Factor Programs and Management
Of the countries surveyed, 66.6% have a structured Human Factors Maintenance Program. Of
these countries that have a structured program, 80% have had it for more than five years. Most
countries agree that the programs in their organizations have improved human factor error
management. The responses on the effectiveness of tools and training to manage human factor
errors in maintenance were mixed in that 54% thought they were adequate while 45% thought
otherwise. However, a good majority, or 95.8% of those surveyed clearly felt that “More needs to
be done to manage HFIM Errors”.
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Table 4.1 Human Factors Management Survey
4.1.1 Most Common Outcomes of Safety Occurrences
The most common outcome of HFIM safety occurrences were “System operated unsafely
during maintenance”. This was followed closely by “Incorrect assembly or orientation of part”.
More than 50% of those surveyed thought that these were the Top two outcomes of safety
occurrences in their organization.
Table 4.2 Most common Outcomes of Safety Occurrences
POS Outcomes %
1 System Operated Unsafely during maintenance 62.5
2 Incorrect assembly or orientation of part 50.0
3 Part/aircraft damaged during repair 33.3
4 Tool lost on aircraft/in maintenance facility 29.0
5 Material left of aircraft 26.6
6 Injury to personnel 25.0
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“Pressure” was the top most likely reason for the occurrence of safety violations. “Pressure”
and “Lack of Training” were the two top reasons for safety violations.
Table 4.3 Most common reasons for the occurrence of the outcomes
POS Outcomes %
1 Pressure 62.5
2 Lack of Training 50.0
3 Fatigue 45.8
4 Supervision 41.6
5 Lack of Equipment 12.5
6 Environment 12.5
In the opinion of those surveyed, more than 50% listed the “Attitudes of Personnel”, “Training
Effectiveness” and “Organizational Culture” as the top factors that need to be reviewed to better
manage human factor errors in maintenance.
Table 4.4 Top HFIM drivers that need reviewing
POS Outcomes %
1 Attitudes of Personnel 58.3
2 Training Effectiveness 54.1
3 Organizational Culture 50.0
4 Processes 33.3
5 Leadership 33.3
6 Management of Information 25
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Figure 4.1 Influence of experience on human factor management survey from A. Xavier, 2005
Comparison of the survey answers by experience level revealed very little differences in the
answers and agreement levels between the three bands of experience levels surveyed.
Figure 4.2 Breakdown of results of those who “strongly agree” that they have a structured HFIM program.
Of those surveyed, 17% “strongly agreed” that they had a structured HF program and that the
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program was showing improvements to HF management. Also, 56% “strongly agreed” that more
was needed to be done to improve the HFIM program.
4.2 Survey Feedback
Several senior professors that were surveyed, most of whom had been teaching maintenance in
the university, had very good comments and feedback during the survey. Some of these comments
were:
1. The main issue in my opinion is “complacency”. A lot is due to repeated jobs over and over. Not
paying attention to the little details.
2. Managers and Supervisors need to be more patient when shops get a lot of work. Most mistakes
are made when technicians get interrupted during their tasks to do other jobs and feel pressure to
always get done quickly. The Technicians are usually very good; it‟s the amount and variety of
different tasks that causes problems. It is hard to do tasks that may be quite complicated when you
are always in a rush.
3. To improve or reduce HFIM management/errors you need:
b. Effective implementation of supervisory training
c. Timely sharing of information (incidents/accidents)
d. Motivation at all levels
e. Involvement of leaders and supervisors with the subordinates
4. Personnel should be trained and watched by supervisors to make sure they are gaining an
understanding of correct processes and staying to the procedures. Personal opinions as to how a job
should be done should be eliminated, in favor of closely following pre-established procedures.
5. I think that the lack of pressure and fatigue are special human error producer. I think generally,
the air forces have to consider a rest time for technicians just like the rest time valid for crew
members.
6. Most common outcome is repeat or recurring of present malfunction due to lack of efficient
maintenance procedures related to HFIM.
b. The first thing that maintenance leaders/managers and maintainers must believe is in the
necessity and help of the HFIM concept.
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c. The most important is psychological factors (i.e. wants ,expectations, attitudes and motivation)
then next comes human sensory factors and physiological factors.
d. As a 16 years aircraft maintenance officer to me the most problematic area for HFIM
management in aircraft maintenance are:
i. Norms of the maintenance people
ii. Night shifts (you‟d better check the effectiveness of shifts and their change over
consequences in A/C maintenance)
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Chapter 5 Discussion
While many research studies in the past have been done mainly on airline organizations, this
research study has also shown consistent results with those studies in the last 20 years. The
management survey conducted revealed very consistent findings thus far on the management of HF
errors in maintenance. The discussion here is a combination of the study done by the researcher and
the comprehensive studies already done by many organizations.
5.1 Human Factor Management Program
It was very comforting to note that many (80%) of the organizations surveyed had
implemented a structured human factor program for at least five years now with a good proportion
(70.8%) of them seeing improvements from these programs. This is a testament to the focus and
attention given by all major aviation agencies such as the FAA, NTSB, CAA, ASTB, and JAA on
the need for educating and evaluating aviation maintainers on the nature and detriment of human
factors.
5.2 Most Common Outcomes of Safety Occurrences
The top three common reasons for the occurrence of safety outcomes which are “pressure”
(62.5%) , “lack of training” (50.0%) and “fatigue” (45.8%) seem to be the clear catalysts for the
most common outcomes which are “system operated unsafely during maintenance”(62.5%) and
“incorrect assembly or orientation of parts” (50.0%). Although aviation operations are high,
operational tempo environments, the „pressure‟ factor has consistently been the main influencing
factor for human factor errors for the last 20 years. Some of the reasons for “pressure” could be due
to lack of training, tools, equipment or just the attitude of the personnel or organizational culture.
Many people have different eustress levels which are the stress level that allows them to perform
optimally. As such, job matching and training needs analysis are vital to ensuring organizations
have the right people at the right place at the right job.
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5.3 Top HFIM drivers that need reviewing
While the top three drivers for human factor errors were “attitudes of personnel”(58.3%),
“training effectiveness” (54.1%) and “organizational culture”(50.0%), the remaining three factors
were just as contributory namely, „processes‟, leadership and „management of information‟. These
six factors are so varied that one can only conclude that it is clearly the view of those surveyed that
there is a need for an extensive review of an organization to eradicate human factor errors. Even
those surveyed who “strongly agreed”(20.8%) that they had a structured HF program, and that the
program was improving the management of human factor errors, felt that “more was needed to be
done to manage human actor errors” (56.6%).
5.4 Influence of experience on human factor management
The results of the survey shows that the experience level had little or no effect on the views of
current human factor management programs, that is, even those with a few years of experience had
similar responses to the effectiveness of human factor management and the types of errors it
produced.
It was evident in the comments and feedback given by the professors and employees of the
aviation organization being surveyed at the end of the survey, as well as personally to me during our
discussions that the three main areas they see as contributory to errors occurring in the workplace
were:
1. Complacency
2. Distraction
3. Not following proper procedures
These contributory human factors support the results of the most common safety outcomes
derived from the survey. These factors are similar to what the “Dirty Dozen” factors by Mr. Gordon
Dupont warn us to take note of daily in aviation maintenance.
The Asian study from 1999 to 2003, after implementing several new initiatives and a
performance excellence framework similar to the MBNQA framework, reaped several significant
results such as a 50% reduction in human factor errors and in many others such as these:
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5.4.1 Safety Culture
This was a new segment of questions that surveyed on the safety and quality culture at the
various levels, e.g. from the organization level down to individuals. Results showed that 99.01%
(51.02% = Strongly Agree; 47.99% = Agree) of personnel agreed that the organization placed strong
emphasis on safety and quality. Similarly, personnel also agreed that management (96.43%),
supervisors (97.30%) and personnel (94.38%) also showed strong emphasis and take safety and
quality seriously.
5.4.2 Safety Quality
A good safety and quality culture is due to the many years of strong and continual safety and
quality emphasis at the various staff and command levels, coupled with the comprehensive safety
and quality programs and initiatives implemented at the various levels as part of the performance
excellence framework reviews.
5.4.3 Reasons for Violations.
The top four reasons remained unchanged, i.e. “Time pressure to complete task”, “Too much
work, too little time,” “Insufficient manpower” and “Unrealistic requirements from management.”
Among the top four reasons, “Unrealistic requirements from management” registered a 9% drop
(35% to 26%), whereas “Time pressure to complete task,” “Too much work, too little time”
“Insufficient manpower” increased by 10%, 11% and 5% respectively.
5.4.4 Percentages
The increase in percentages for the top three reasons for violations correlated with the increase
in airline schedules, especially after the 911 accident, where more standby requirements were put in
place.
5.4.5 Types of Violations
The results showed an overall improvement of 4% for the six common types of violations
observed everyday and once a week. Analysis was also done by examining whether there were any
adverse trends by specific units or by specific group of personnel (years of service). The results
showed that there was no specific trend.
5.4.6 Frequency of Violations
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There was an across-the-board reduction in the frequency of violations being observed,
particularly, a significant reduction of 100% was noted for "Very Infrequent," from 21% to 43%.
Slight improvements were also noted for "Everyday" (5% to 4%) and "Once a week" (9% to 6%).
5.4.7 Calling Time-Out
The results showed an overall drop of 11% (50% to 39%) in holding back to call time-out, with
an across-the-board drop in all the concerns. "Fear of being labeled as lazy" registered a significant
drop of 23%. These results showed that calling time-out is slowly gaining acceptance.
5.4.8 Analysis of the Problem
Analysis revealed that the length of service played a part in the willingness of personnel to call
time-out. The more senior personnel concerns were "Do not wish to 'let down' supervisors or
management" and "Worry for not meeting operations requirements." This is not surprising because
they are the group who holds the responsibilities to ensure that the work is completed on time.
Though it shows that they are committed, it must not be overdone. A balance must be struck, or else
it would create unnecessary pressure on the junior to hold back on calling time-out when the real
need arises. This effect was indeed reflected by the junior as one of their concerns was "Fear that
supervisors are not supporting for calling time-out." Other reasons include "Pressure from
colleagues," "Fear of being labeled as lazy” and "Manpower shortage."
5.4.9 Over-Time (OT) Management
The results showed a 16% reduction in the frequency of OT done weekly. This is most likely
contributed by the following:
a. A 6% reduction of “Unrealistic requirements from management
b. Better (3% improvement) co-ordination among multi-trade rectification.
c. Lesser (45% improvement) waiting time (<2 hours) between jobs
d. Better (3% improvement) time management of personnel.
e. Lesser (8% lesser) secondary duties.
f. 11% increase in “Easy way out (taking short cuts)”.
5.4.10 Open Reporting
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Open reporting is a concept of reporting those minor/major incidents that did not result in
damage or anything clearly visible to management or your peers but yet can contribute significantly
when shared amongst peers so as to create a culture of sharing and learning. The open reporting
concept has, over the years, encouraged people from reporting mistakes/incidents without the fear
of being punished. Although there was a 6% drop on “Open reporting is well accepted in the
organization” to 84%, the willingness to open report has improved. Forty percent of personnel held
back from open reporting due to “Uncertainty of what the consequences would be” if they open
report.
Chapter 6 Conclusion and Recommendation
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In summary, the researcher‟s hypothesis for an urgent need for a more holistic and integrated
approach to managing human factor errors in maintenance is supported by this study. The researcher
recommends a performance excellence framework, like the MBNQA framework, be adopted to
review the organizations people, processes and results. The solutions adopted today, in terms of
organizational reviews and human factor training, have been done in isolation and not as an
integrated review of the entire organization. The results from the Asian study from 1999 to 2003
reported in this study, supports the researcher‟s hypothesis and proposed solution to the problem.
Many experts believe and this study supports the argument, that there has to be a
transformation. Without a doubt, unless aviation maintenance organizations transform their people,
processes and antiquated operational strategies, they will not succeed in eliminating the “Dirty
Dozen” from their organizations.
Figure 6.1 Human Performance X’cellence Model
6.1 Recommendation
Based on the results of the survey, and the downward trends from the Asian study between
1999 and 2003 , it is recommended that aviation maintenance organizations adopt a human
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performance excellence model like the MBNQA framework to reduce, if not eradicate, the uptrend
and spate of avoidable human factor errors in their organizations. There are many areas that an
organization can focus on but results of surveys in the last 20-30 years suggest that the key areas
requiring improvement are:
1. Leadership and Organizational Culture
2. Learning and Growth
3. Measurement, Analysis and Knowledge Management
4. Process Management
A major change that is required in these organizations is the reduction in time pressure
imposed on their staff to complete maintenance jobs and tasks. Organizations that adopt a
performance excellence framework should tailor the framework to their needs rather than
implement the details of the framework lock-stock and barrel. Instead, organizations should fit their
systems and processes into the framework and make changes where necessary. The key thrust for
performance excellence is to establish a culture of continuous improvement and innovation that
builds upon a strong foundation of quality, professionalism and team excellence, always.
Figure 6.1 Human Performance Excellence Model
In order to establish a culture of excellence, organizational reviews cannot be restricted to
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certain areas of the aviation business such as safety and training. Reviews done in isolation
underestimate the interdependency of several areas in a complex organization such as the aviation
industry. A framework such as the one proposed in the tables that follow, provide the over-arching
framework for an organization to review its current health and the issues that require attention to
prevent an incident or accident from occurring.
Table 6.1 Performance Excellence Framework in relation to HFIM
Criteria Objectives HFIM relation
Leadership
And
Organizational
Culture
How senior executives develop, communicate
and demonstrate the purpose, vision and goals
for the organization that focus on
Safety/Quality.
How the organization translates these values
into policies, practices and behavior.
How the organization permeates a culture
consistent with its values.
How the organization overcomes any difference
between the current culture and the desired
culture
+ Human Factor goals, targets.
+ Management view on errors.
+ Open reporting, tools for
data collection.
+ Training, rewards, feedback.
+ Surveys, process reviews,
crisis teams to review
organization.
Measurement,
Analysis and
Knowledge
management
How information needed to drive day to day
management and improvements to
organizations performance is selected and
managed.
List key types of information and describe how
they are related to organizations performance
+ Key performance indicators
for Safety must be selected
and managed.
+ Create a database of cases
and incident/accidents and
measure its effect such as cost
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objectives & goals.
How the organization ensures information is
reliable, accessible and disseminated quickly to
employees and external parties.
How the organization evaluates and improves
its management of information How
comparative and benchmarking information is
selected to improve the organizations
performance.
of a HF error etc.
+ Accessibility of database
and sharing of lessons learnt
to prevent a re/occurrence
through meetings/forums etc.
+ Implementation of safety
information system.
+ Benchmark accident
statistics and do comparative
studies with leading
companies.
Learning &
Growth
Describe the organizations human resource
requirements and plans, based on the
organizations strategic objectives and plans.
How the organization implements and reviews
its human resource plans.
Mechanism available to encourage employee
involvement and commitment to teamwork,
innovation and the achievement of the
organizations goals and objectives.
How the organization identifies and reviews it‟s
education, training and development needs to
support its goals and objectives.
How the organizations employee performance
+Manpower levels with
relation to task levels, training,
rewards, staff performance
management and recognition.
+ Deployment of personnel
based on needs, recognition
system and constant review
based on complexities of
tasks.
+ Implementation of cross
functional/project mgt teams,
innovations efforts to improve
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and recognition systems support its objectives
and goals.
work environment.
+Training needs analysis,
management system, and
review based on HFIM
trends/cases.
Interviews with staff on their
needs.
+Morale of employees, task
saturation, promotion and
rewards.
Process
Management
The organization has a systematic process to
acquire, evaluate and implement creative ideas.
The organization‟s key processes have clear
objectives and targets.
The organization has a system to analyze root
causes, take prompt corrective action and
prevent future occurrence when a process fails
to meet specified standards or targets.
There are various methods to access the quality
and performance of the organization‟s key
business processes.
+Safety improvements,
process changes.
+Is safety one of the key
processes?
+Safety Management system
that tracks and follow-ups on
safety findings.
+Audits/inspections and
feedback channel.
+Committee/program/track
follow-up actions.
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References
[1] David C. Nagel Human Factors in Aviation [M]. Waltham, Massachusetts, Academic Press, 1989.
[2] FAA Human Factors Guide for Aviation Maintenance[S]. United States: FAA, 2002.
[3] Jensen R. Opening address for the 9th International Symposium on Aviation Psychology[A], Toronto, Canada
1997.
[4]Guidance Material on the UK CAA Interpretation of Part-145 Human factors and error Management
Requirements[S]. Annex 6, part 1.
[5]Guidance Material on the UK CAA Interpretation of Part-145 Human factors and error Management
Requirements[S]. Annex 6, part 1, Definitions.
[6] ICAO HF Training Manual[S]. Part 2, Para 1.4.3.
[7] ICAO HF Training Manual[S]. Part 2, Para 1.4.6.
[8] Human Resource Development and the Use of Results[C]. Hertz, 2004.
[9] The dirty dozen[N]. Gordon Dupont, System Safety Services.
[10] Human Resource Development and the Use of Results[C]. Hertz, 2004.
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Acknowledgements
First and Foremost, I would like to express my sincere gratitude to my advisor Prof. Cao YuYuan
for the continuous support of my Graduation Thesis, for his patience, motivation, enthusiasm, and
immense knowledge. His guidance helped me in all the time of research and writing of this thesis. I
could not have imagined having a better advisor and mentor for my Graduation Thesis. My sincere
thanks also goes to my fellow classmate and friend Dennis Ochengo for his valuable advice and
priceless time on every turn during my research. I would like to thank all my fellow Bach mates
who gave invaluable information without which this thesis would not have been possible.
Lastly, and most importantly, I wish to thank my parents. They bore me, raised me, supported
me, taught me, and loved me. To them I dedicate this thesis.
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Appendix
HUMAN FACTORS MANAGEMENT SURVEY
Name:
(Optional)
Years in
organization :
> 20 years < 10 years None
□ □ □
Job
Description
(if any):
Rank (if any): HFIM
Awareness
Poor Good Excellent
□ □ □
Involved in
Maintenance? Y/N
Human Factors (HF) Fact: Global statistics indicate that 80% of aviation accidents are due to human
errors with 50% due to maintenance human factor problems. Most programs currently implemented are
designed to identify the HF errors, educate the personnel on their causal potential, suggest ways to
contain and correct the problem; and create a HF error-free environment. However, HFIM errors are
still on the rise today.
Please mark your response in boxes
Strongly agree Strongly
disagree
6 5 4 3 2 1
1. Human Factors Programs
1.1 There is a structured Human Factors Program in your
Maintenance organization?
1.2 If yes, how many years has it been in existence?
> 10 years 5-10 years < 5
years
1.3 Is it important to have one?
2. Human Factors Management
2.1 The HFIM programs currently implemented have
improved the management of human factor errors?
2.2 The training and tools currently available in the aviation
organizations are sufficient to manage HFIM?
2.3 More needs to be done to manage HFIM errors in
maintenance?
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3. Most Common Outcome of Safety Occurrences (check all that apply)
3.1 In your opinion, which of these are the most common outcomes of HFIM safety occurrences?
□Incorrect assembly or orientation of part
□Injury to personnel
□Tool lost on aircraft / in maintenance facility
□Part/aircraft damaged during repair
□Material left on aircraft
□System operated unsafely during maintenance
3.2 The most likely reason for the occurrence of these outcomes
□Pressure
□Fatigue
□Lack of training
□Supervision
□Lack of equipment
□Environment
3.3 In your opinion, HFIM errors can be managed better by reviewing it‟s
□Leadership
□Processes
□Management of information
□Organizational culture (not just safety)
□Attitudes of personnel
□Training effectiveness
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4. Do you have any additional comments or suggestions to improve or reduce HFIM
management/errors?
Thank You for your valuable input.