ANS-TRAINING
SETTEMBRE 2011
FATTORI UMANI
ATCO Basic Training
Human Factors
Student Manual
Training
Document
VERSIONE DRAFT
Introduction to Human Factors
INDICE
BASIC TRAINING
HUMAN FACTORS
TRAINING DOCUMENT
Table of contents
1 INTRODUCTION TO HUMAN FACTORS
PAG. 8
1.1 Why Human factors?
1.1.1 Definition
1.1.2 Why human factors is a subject in this course
1.1.3 The concept of systems
1.1.4 Consequences of a systems failure in ATS
1.1.5 ATM in systems terms
1.1.6 The SHELL model
1.1.7 Overview on the topics that are covered in the course
PAG. 9
PAG. 9
PAG. 9
PAG. 10
PAG. 11
PAG. 11
PAG. 12
PAG. 13
1.2 Recap
PAG. 14
1.3 References
PAG. 14
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1. INTRODUCTION TO HUMAN FACTORS
Training objectives Student shall…
L
Subj
Ref
1
Define Human Factors
1
INTR
2.1.1
2
Explain why Human Factors is a subject in this course
2
INTR
2.1.2
3
Explain the concept of systems
2
INTR
2.1.3
4
Explain ATM in systems terms
2
INTR
2.1.3
5
Recognise the consequences of a systems failure in the ATS
1
INTR
2.1.3
6
Explain the use and benefits of the SHELL model
2
INTR
2.1.4
7
Explain the information requirement of ATC
2
INTR
2.1.4
8
List the topics that will be covered in the course
1
INTR
2.2.1
9
List the reference documents used
1
INTR
2.2.2
L
CCC Level
Subj CCC subject abbreviation
Ref CCC reference code
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1.1 WHY HUMAN FACTORS?
1.1.1 Definition
Human Factors is the study of how humans behave physically and psychologically in relation to particular environments, products or services. Human Factors is concerned with the
application of what we know about people, their abilities, characteristics, and limitations to
the design of equipment they use, environment in which they function, and jobs they perform. Ergonomics (or human factors) is the application of scientific information concerning
humans to the design of objects, systems and environment for human use.
1.1.2 Why human factors is a subject in this course
It was first calculated in 1940 that three out of four aircraft accidents were due to human
failures of one kind or another. This figure was confirmed by the International Air Transport
Association (IATA) at their Istanbul conference in 1975, where it is well recognised that the
initial development of Human Factors within aviation began. The high number of accidents
resulting almost entirely from Human Factors led ICAO to implement Human Factors training requirements and licensing requirements.
In 1977 two aircraft collided on the runway of Tenerife, 583 people died. Reasons were:
Communication and ranking problems, the airport was crowded, all pilots wanted to take
off quickly, the weather was very bad. Within a year after the accident, one of the airlines
involved had launched the first “Human Factors Awareness Course”. Human Factors intends to have a positive impact on safety in ATM. The knowledge about personal behaviour,
performance and effects of stress will help to recognize potential error and prevent it beforehand. People working close together now and then get into conflict with each other. It
becomes easier to handle critical situations when we are aware of safety-related processes
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in teams. Our own attitude towards the job is essential for a good and safe performance in
air traffic control. What stresses controllers in their daily work and how can they deal with
it? What influences our teamwork? Why do we sometimes misjudge situations? How do we
communicate effectively and without misunderstandings? How can the human deal with
the technological and highly automated work environment? These are only a few questions
Human Factors is trying to answer.
1.1.3 The concept of systems
The ATM System consists of at least three elements. First we need people to operate within
the system, to fulfil the task the system was designed for. In addition we need certain procedures, how the people are supposed to do their job. Most of the times within the system
there is specific equipment to help the people to apply the procedure and to do their work
efficiently.
Within the ATM System, there are various people working. Not only controllers, but also
FDO, the pilots and technicians belong to the ATM system. Procedures in the ATM System
are all kind of regulations, agreements, the communication and the data processing, etc.
Equipment within the ATM system can be the radar, radio, telephones or touch input devices.
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1.1.4 Consequences of a systems failure in ats
If one element of the system fails it can lead to decreased capacity and safety. The worst
case would be the complete breakdown of the system.
1.1.5 ATM in systems terms
Systems never stand alone by themselves but are parts of other systems and influence each
other. The ATM system can be looked at as a system by itself with the components people,
procedures and equipment, but at the same time it is also a system which contains other systems, e.g. ATS, ASM and ATFCM which again contain the components people, procedures
and equipment.
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1.1.6 The shell model
The SHELL model was originally developed by Edwards in 1972 as SHEL-Model. In 1975
Hawkins modified it and added the second L to it. It is a theoretical framework designed
to aid in the analysis of workplace interactions between people (Liveware) and all other
aspects of the working environment: software, hardware, environment and other liveware.
The speciality of this model in comparison to others is that the Liveware, the human, stands in the centre of the model and the workplace is being looked at from his point of view.
Hardware in the ATC means radars, telephones with headsets, computers, displays of all
kinds, touch input devices etc. Software stands for the actual software which is being used
by the systems but as well what we called procedures before: the rules, policies, informal
guidelines in use. The environment includes factors such as temperature, light and noise
levels. Liveware are the colleagues, the supervisors, managers as well as the customers, i.e.
the pilots. The SHELL model looks at the interaction between the components.
Examples for a Liveware-Software interaction would be that a controller does not apply
a certain rule correctly because it is not clear to him. Maybe the rule is too complicated,
maybe it cannot be applied in the intended way. An example for a Liveware-Hardware interaction: imagine a controller being not able to look out of the tower window because the
chairs cannot be brought up high enough, or touch input devices which don’t work when
you touch them with your fingers.
Liveware-Environment: the sun is shining directly into the eyes of the tower controller. He
is not able to see anything. Or another example: the noise level in the control room is on
such a high level – maybe there is construction work going on – that the controllers are not
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able to hear the transmissions of the pilots. The edges of the parts of the SHELL-model are
not straight because this is where the problems occur. The model helps to identify those
problems beforehand, e.g. when designing new systems or creating new procedures, and
to find solutions as soon as difficulties arise. With the application of the SHELL model the
human-machine interface and the working conditions for the controller especially can be
improved.
1.1.7 Overview on the topics that are covered in the course
The Human Factors Basic Course consists of 5 topics which will be covered in ten lessons
• Introduction to Human Factors
• Human Performance
• Human Error
• Communication
• The Work Environment
“Human Performance” deals with individual behaviour, professional conduct, health and
well being, teamwork as well as basic needs of people at work. Stress and Stress Management are also subjects which will be discussed.
“Human Error” defines Human Error and shows its relevance in respect to safety.
Classification of Human Error is a sub-topic as well as a model which explains how errors
occur (The Reason model)
“Communication” covers the communication process and the communication modes.
“Work Environment” looks more deeply at the hardware part of the SHELL model. It is
about equipment and tools and deals with automation.
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1.2 RECAP
• Define “Human Factors”
• Why do you think Human Factors is important for a controller?
• What is special about a system?
• What happens to the system if one element within fails?
• Name the components of the SHELL model
• What is the benefit of the SHELL model?
• Give an example for a Liveware-Hardware-interaction!
• Why is it important to match humans and equipment?
1.3 REFERENCES
Cram, A (2005). SHELL model analysis of the info.csu Call Centre. Retrieved Oct, 13,
2007 from www.andrewcram.com/SHELLmodel.pdf
International Civil Aviation Organization (ICAO) (1998). Human Factors Training Manual,
Doc 9683-AN/950, Montreal
Isaak, A. R, Ruitenberg, B. (1999). Air Traffic Control: Human Performance Factors, Aldershot: Ashgate
Krieger, D. J. (1998). Einführung in die allgemeine Systemtheorie. 2. unveränderte Auflage, München: Fink
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Human Performance
INDICE
ATCO BASIC TRAINING
HUMAN FACTORS
TRAINING DOCUMENT
Table of contents
2 HUMAN PERFORMANCE
PAG. 18
2.1 Individual behaviour
2.1.1 Differences and commonalities that exist between people
2.1.2 Basic needs of people at work
2.1.3 Dangers of boredom, overconfidence,
complacency and fatigue
2.1.4 The effect of health on performance
PAG. 19
PAG. 19
PAG. 20
PAG. 22
2.2 Recap
PAG.24
2.3 References
PAG. 24
PAG. 23
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2. HUMAN PERFORMANCE
Training objectives Student shall…
L
Subj
Ref
1
Explain the differences and commonalities that exist between
people
2
HUM
3.1.1
2
Explain the dangers of boredom
2
HUM
3.1.2
3
Explain the dangers of overconfidence and complacency
2
HUM
3.1.3
4
Explain the dangers of fatigue
2
HUM
3.1.4
5
Consider the effect of health on performance
2
HUM
3.3.1
6
List the basic needs of people at work
1
HUM
3.5.1
7
Characterize the factors of work satisfaction
2
HUM
3.5.2
L
CCC Level
Subj CCC subject abbreviation
Ref CCC reference code
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2.1 INDIVIDUAL BEHAVIOUR
2.1.1 Differences and commonalities that exist between people
Poor performance always is a possible safety risk. Therefore it is important to know which
factors influence our work and performance as controllers.
Even if the Hardware, Software, Environment and the other Liveware were exactly the
same the system would not operate exactly the same because we, the Liveware in the middle are not the same. Every person has his own personality, his own special ways of doing
things, his characteristics and attitudes and so on. Differences and commonalities that exist
between people can be:
• cultural background
• experiences
• language
• attitudes
• age
• training
• hobbies, interests
• gender
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2.1.2 Basic needs of people at work
2.1.2.1 The Tromsö Incident
In August 1993 an incident took place over a locator near Tromsö, Norway, where a loss of
separation occurred between a Twin Otter and a Boeing 737. The Twin Otter was at 5000ft
and the B737 was cleared to 7000ft by ATC. When this clearance was read back the pilot
said he was descending to 5000ft and this error was not spotted by the controller.
After a few minutes the B737 reported over the locator at 5000ft. The Twin Otter crew, having passed the locator shortly before at 5000ft as well, immediately descended to 4500ft,
while the controller instructed the B737 to climb to 6000ft. Afterwards it was determined
that the horizontal distance between the two aircraft was about 4NM during the time when
vertical separation was not established.
In the subsequent investigation the following findings were recorded:
• There was a severe shortage of staff at the time of the incident
• The controller had worked on average 40 hours of overtime per month in the three months
preceeding the incident
• The week before the incident the controller worked seven shifts; two of these were overtime shifts and two of them were nightshifts
• The controller was at the end of a period of eleven days at work without any days off
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• There was no relief for the two controllers in the tower (working TWR and APP control
respectively); consequently the controllers had to eat their meals at their work stations
during quiet periods
• The tower cab was too small: originally designed for one controller plus one assistant, it
often was occupied by a crew of three controllers, one assistant and two trainees
• Flight planning and pre-flight briefing took place in the tower
• Controllers at Tromsö were reluctant to refuse overtime work, for that would increase the
burden on their colleagues
The official recommendation to the Norwegian CAA were:
• Intensify efforts to increase staffing permanently
• Take action to reduce the use of overtime among controllers
• Improve the physical working conditions
• Consider establishing a concept for control rooms during aircraft operations
• Establish rules for controllers enabling them to assess their own physical and mental
health prior to the provision of air traffic control service
2.1.2.2 Basic needs and work satisfaction
According to a job-characteristic-model proposed by Richard Hackman and Greg Oldham
in 1976 people basically want their work to be meaningful, they want to be responsible for
the outcome and the want to know the results of their work. These three items can be considered basic needs of people at work. If the basic needs are satisfied the workers are highly
motivated and show a high work performance. The work satisfaction is great. People don’t
miss many working days (absenteeism) and don’t give up the job (turnover) easily.
The outcome of high motivation and work satisfaction is of course of great interest for
every company. Therefore it is important to meet the basic needs of people at work. This
can be achieved by creating an environment which helps to meet the basic needs. These
environmental factors are: skill variety, task identity and task significance, autonomy and
feedback. The first three factors help to gain the feeling of meaningfulness. If the various
skills are needed and the task seems important to the worker the work as a whole is seen as
meaningful.
Autonomy means that the worker can make decisions on his own and is not just a tiny part
in a huge process. Feedback is important in order to know about the results of work.
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2.1.3 Dangers of boredom, overconfidence, complacency and fatigue
Individual behaviour includes dangers to safety. Everyone can imagine that stress is a danger to safety, but not many people think of boredom as a danger to safety, but it is – especially when working in an automated environment. Boredom is a Liveware issue and it may
occur when there is substantial activity which has all become routine, requires little effort
and is not much challenge and of not much interest to the controller.
It is difficult for the controller to maintain direct and active involvement in the control loop.
Boredom tends to increase as skill and experience increase. So the better you get, the higher
the danger of boredom 21 becomes. The job of a controller is very demanding. A controller
has to make decisions constantly and quickly. He therefore has to be very confident in his
abilities. There is no room for indecisive persons in ATC. However, confidence can lead to
overconfidence and complacency.
If a job never tests an individual’s limitations, every difficulty may seem familiar and every
problem foreseeable – this can induce complacency. Another important Liveware issue is
fatigue. When people are over-tired, their judgement can be impaired, and the safety and efficiency of the ATC service can be put at risk. Controllers are responsible for not impairing
their decision making by tiredness or fatigue.
On the other hand the organisation is responsible for offering an environment such as working hours which enable enough rest time and breaks for the controller. Sleep disturbance
can be the result of personal stress or worries. The consequence of sleep disturbance might
be fatigue at work. To work heavy traffic requires a high level of concentration. After a longer period of time the brain becomes tired. The result here as well might be fatigue.
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2.1.4 The effect of health on performance
Shift work may influence the performance in a negative way. Firstly because it is difficult
for the body to constantly adjust to the different working times. There is no regularity which
would be better for the human organism. Also, due to the shift work many social contacts
cannot be held the way we wish. This causes problems and leads to stress or dissatisfaction which in the end reduces the performance of the controller. Studies regarding working
hours show that the longer you work the poorer you perform.
Therefore breaks during which the controllers really relax are very important. Lack of sleep
leads to a slower brain activity. Decision making becomes poorer and the controller’s job
mainly is a decision making task. Therefore regular and sufficient sleep is essential for a
controller. A person’s performance is reduced by the taking of drugs of any kind, such as
alcohol or medicine. Also the consumption of psychoactive substances reduces the working
ability of people. Therefore, whenever it says that a medicine reduces the ability to concentrate or that one should not drive a car after having taken the medicine the person should not
work as a controller. Stress is a factor which reduces the performance as well.
To keep your performance on a high level you have to keep your body and mind healthy.
Healthy and regular meals are important as well as keeping your body fit. Regular sportive
activities will help you to stay in shape for such a demanding profession. The activity will
also help you to keep your body and mind in balance and to reduce the stress which you will
have to deal with during your work. Your body is your own responsibility and you can do
with it whatever you like. But remember, when you are sitting down to take over control,
you are also taking over the responsibility for many, many people who trust you and your
performance. Keep this in mind!
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2.2 RECAP
• Which differences exist between people?
• List basic needs of people at work!
• What is necessary for work satisfaction to develop?
• What is boredom caused by and why can boredom be dangerous?
• Explain overconfidence and complacency – why can they be dangerous?
• Why is fatigue dangerous for a controller?
• Explain the connection between the health and the performance of a controller!
• Why is it important for a controller to take care of his body?
2.3 REFERENCES
International Civil Aviation Organization (ICAO) (1998). Human Factors Training Manual,
Doc 9683-AN/950, Montreal
Map of Tromsö: www.notur.no/notur2004/tromso_endelig.JPG retained Oct 23rd, 2007
Job-characteristic-model by Hackman and Oldham: Wikipedia, retrieved Dec 12th, 2007
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Stress
INDICE
ATCO BASIC TRAINING
HUMAN FACTORS
TRAINING DOCUMENT
Table of contents
3. STRESS
PAG: 28
3.1 Stress
3.1.1 Stress symptoms and sources
3.1.2 Different kinds of Stress
3.1.3 Stages of stress
3.1.4 Entering a State of “Flow”
3.1.5 Techniques for Stress Management
PAG. 29
PAG. 29
PAG. 31
PAG. 32
PAG. 34
PAG. 35
3.2 Recap
PAG.44
3.3 References
PAG. 44
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3. STRESS
Training objectives
L
Subj
Ref
1
Consider the effect of health on performance
2
HUM
4.3.1
2
Recognise stress symptoms and sources
1
HUM
4.6.2
3
Define stress
1
HUM
4.6.1
4
Describe the stages of stress
2
HUM
4.6.3
5
Describe techniques for stress management
2
HUM
4.6.4
L
CCC Level
Subj CCC subject abbreviation
Ref CCC reference code
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3.1 STRESS
3.1.1 Stress symptoms and sources
Health and Performance both suffer from the effect of stress. The sources of stress are the
so-called stressors. Of course a death of a loved person or a big event such as a wedding or
a birth of a child are stressful events but what causes health problems and influences our
performance in a negative way are the little, every day stressors like the ones:
• too much work to do
• pain
• too many appointments
• time pressure
• noise
• heat/cold
• conflicts, anger
• traffic jam
• exams
• parents
• shopping
• interruptions
• people constantly talking on the mobile phones
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Stress symptoms are reactions of the body, reactions which we realize through our feelings
and there are reactions which we can see by the action a person takes, by his or her behaviour:
Body
Feelings
Behaviour
• heartbeat
• tenseness
• sweat
• fast breathing
• blood pressure
• pain
• anger, rage
• anxiety
• disappointment
• sadness
• irritability
• fatigue
• being unjust
• becoming loud
• becoming hectic
• smoking
• eating
• doing many things at once
What happens between the source and the symptom of stress? If the source is a traffic jam
and the reaction is smoking a cigarette or anger, why is the traffic jam causing such a reaction. Where is the link between traffic jam and smoking a cigarette? It is the thought that is
being triggered by the source which is causing the stress reaction!
The traffic jam is triggering the thought “I will be too late, I will not make it!” It is the
thought which is causing the stress reaction, not actually the traffic. Stress can be defined as
a survival mechanism, a natural body reaction to a “dangerous” situation. In the old ages,
when a bear was about to attack us we quickly had to fight or flee. There was no time to
think the situation through. By the time we would have come to a conclusion the bear probably would have made the decision for us…
The body takes over control and within a split of a second reacts to this dangerous situation:
blood is being pumped into the muscles (so that we can run!) and the face turns pale. The
digestion stops (we don’t need to eat anything at this moment anyway) and the blood vessel
contract so that bad injuries are avoided. There are many more reactions going on in the
body.
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3.1.2 Different kinds of stress
Sometimes the pressures and demands that may cause stress can be positive in their effect.
One example of this is where sportsmen and women flood their bodies with fight-or-flight
adrenaline to power an explosive performance. Another example is where deadlines are
used to motivate people who seem bored or unmotivated. This kind of stress is called “Eustress”. Eustress is a type of short-term stress that provides immediate strength.
Eustress arises at points of increased physical activity, enthusiasm, and creativity. Eustress
is a positive stress that arises when motivation and inspiration are needed. Distress is a negative stress brought about by constant readjustments or alterations in a routine. Distress
creates feelings of discomfort and unfamiliarity. There are two types of distress. Acute
stress is an intense stress that arrives and disappears quickly. Chronic stress is a prolonged
stress that exists for weeks, months, or even years.
Someone who is constantly relocating or changing jobs may experience distress. In most
work situations jobs, our stress responses cause our performance to suffer. A calm, rational,
controlled and sensitive approach is usually called for in dealing with most difficult problems at work: Our social inter-relationships are just too complex not to be damaged by an
aggressive approach, while a passive and withdrawn response to stress means that we can
fail to assert our rights when we should.
Before we look further at how to manage stress and our performance, it is important to look
at the relationship between pressure and performance in a little more detail, first by looking
at the idea of the “Inverted-U”, and second by looking at “Flow”. This is the ideal state of
concentration and focus that brings excellent performance.
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3.1.3 Stages of stress
Pressure & Performance – the Inverted U The relationship between pressure and performance is explained in one of the oldest and most important ideas in stress management, the
“Inverted-U” relationship between pressure and performance. The Inverted-U relationship
focuses on people’s performance of a task. Hypostress: When a controller is bored or feels
unchallenged he feels very little pressure (stress) on himself. The performance is very low
as well – the chances for mistakes or errors are high.
When there is very little pressure on us to carry out an important task, there is little incentive for us to focus energy and attention on it. This is particularly the case when there may
be other, more urgent, or more interesting, tasks competing for attention. As pressure on us
increases, we enter the “area of best performance”. Here, we are able to focus on the task
and perform well – there is enough pressure on us to focus our attention but not so much
that it disrupts our performance. We are all aware that we have a limited short-term memory: If you try to memorize a long list of items, you will not be able to remember more than
six or eight items unless you use formal memory techniques.
Similarly, although we have huge processing power in our brains, we cannot be conscious
of more than a few thoughts at any one time. In fact, in a very real way, we have a limited “attentional capacity”. As we become uncomfortably stressed, distractions, difficulties,
anxieties and negative thinking begin to crowd our minds. This is particularly the case
where we look at our definition of stress, i.e. that it occurs when a person perceives that
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demands exceed the personal and social resources the individual is able to mobilize. These
thoughts compete with performance of the task for our attentional capacity. Concentration
suffers, and focus narrows as our brain becomes overloaded.As shown in the figure, this is
something of a slippery slope: the more our brain is overloaded, the more our performance
can suffer. The more our performance suffers, the more new distractions, difficulties, anxieties and negative thoughts crowd our minds.
Hyperstress: Imagine a controller who has too much traffic to handle. He thinks he cannot
manage the high amount of traffic. He feels an enormous amount of pressure and stress.
The chances of errors increases, the performance of the controller decreases. Distress: The
procedures (Software!) within a system have changed. The controller has been forced to
readjust to the change. This was stressful for him, he feels very uncomfortable because he is
not used to the new procedures yet. His performance is not as good as usual. Other research
has shown that stress reduces people’s ability to deal with large amounts of information.
Both decision-making and creativity are impaired because people are unable to take account of all the information available. This inability accounts for the common observation
that highly stressed people will persist in a course of action even when better alternatives
are available. It also explains why anxious people perform best when they are put under
little additional stress, while calm people may need additional pressure to produce a good
performance.
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3.1.4 Entering a state of “flow”
The following information (1.1.4) may be considered as additional information. When you
are operating in your “area of best performance”, you are normally able to concentrate
and focus all of your attention on the important task at hand. When you do this without
distraction, you often enter what Professor Mihaly Csikszentmihalyi of Chicago University
describes as a state of ‘flow’. This involves “being completely involved in an activity for
its own sake. The ego falls away. Time flies. Every action, movement, and thought follows
inevitably from the previous one, like playing jazz.
Your whole being is involved, and you’re using your skills to the utmost”. You perform
at your best in this state because you are able to focus all of your efforts, resources and
abilities on the tasks at hand. While you are sufficiently motivated to resist competing temptations, you are not so stressed that anxieties and distractions interfere with clear thought.
This is an intensely creative, efficient and satisfying state of mind. It is the state of mind in
which, for example, the most persuasive speeches are made, the best software is developed,
and the most impressive athletic or artistic performances are delivered.
Helping Yourself to Get Into Flow: One of the frustrations of management is that managers
can feel that they lose the ‘right’ to these periods of deep concentration when they must be
readily available to others, and be able to deal with the constantly changing information,
decisions and activities around them. Studies of good managers show that they rarely get
more than a few minutes alone without distraction. This alone can be frustrating, and can
contribute strongly to managerial stress.
In jobs where concentration is a rare commodity, there are various solutions to creating the
periods of flow that sustain good performance. Solutions include working from home, or
setting aside parts of the day as quiet periods. Another solution might be to delegate the activities that require the greatest levels of concentration, allowing the manager to concentrate
on problems as they arise, serving to create a flow of its own.
http://www.mindtools.com/stress/UnderstandStress/StressPerformance.htm
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3.1.5 Techniques for stress management
Stress is being caused by the thought which is being triggered by the situation. Since it is
not possible to fight the symptoms we can only do something about the situations or the
thoughts, e.g. avoid traffic jams and time pressure before work by leaving a little earlier
so that a traffic jam is no longer a threat. Time management helps to cure many situations.
Some of the suggestions which were covered during the lesson about learning techniques
help to get rid of some of the stress sources caused by bad exam preparations.
Some of the sources however cannot be avoided. The autopilot goes on and the thought in
our head causes the stress reaction. At this point it helps to be aware of this process. Just like
in an airplane we need to switch off the autopilot and think about the situation consciously:
What will happen if I arrive late? Will I be killed? Is it going to be life threatening? No! So
there is actually no need for a survival reaction of the body, is there?
It helps to realize: yes, I am nervous and it is good to be nervous because the adrenalin will
help me to perform well. Think of the eustress!
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3.1.5.1 Exercise
Exercise, especially stamina training strengthens the cardiovascular system. A person exercising regularly becomes more stress resistant.
The following information of this chapter (4.1.5.1) may be considered as additional information. Physical exercise is manual activity that develops or maintains physical fitness and
overall health. It is often practiced to strengthen muscles and the cardiovascular system,
and to hone athletic skills.
Frequent and regular physical exercise boosts the immune system, and helps prevent diseases of affluence such as heart disease, cardiovascular disease, Type 2 diabetes and obesity.
It is also improves mental health and helps prevent depression. Exercises are generally
grouped into three types depending on the overall effect they have on the human body:
1. Flexibility exercises such as stretching improve the range of motion of muscles
and joints.
2. Aerobic exercises such as cycling, walking, running, hiking, and playing tennis focus on increasing cardiovascular endurance.
3. Anaerobic exercises such as weight training, functional training or sprinting increase
short-term muscle strength.
Physical exercise is important for maintaining physical fitness and can contribute positively to maintaining a healthy weight, building and maintaining healthy bone density, muscle strength, and joint mobility, promoting physiological well-being, reducing surgical
risks and strengthening the immune system. Frequent and regular aerobic exercise has been
shown to help prevent or treat serious and lifethreatening chronic conditions such as high
blood pressure, obesity, heart disease, Type 2 diabetes, insomnia, and depression.
Strength training appears to have continuous energyburning effects that persist for about 24
hours after the training, though they do not offer the same cardiovascular benefits of aerobic
exercises. Exercise can also increase energy and raise one’s threshold for pain.
There is conflicting evidence as to whether vigorous exercise (more than 70% of VO2 Max)
is more or less beneficial than moderate exercise (40 to 70% of VO2 Max).
Some studies have shown that vigorous exercise executed by healthy individuals can effectively increase opioid peptides (aka endorphins, a naturally occurring opiate that in conjunction with other neurotransmitters is responsible for exercise induced euphoria and has
been shown to be addictive), positively influence hormone production (i.e., increase testosterone and growth hormone), benefits that are not as fully realized with moderate exercise.
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Exercise has been shown to improve cognitive functioning via improvement of hippocampusdependent spatial learning, and enhancement of synaptic plasticity and neurogenesis. In
addition, physical activity has been shown to be neuroprotective in many neurodegenerative and neuromuscular diseases. For instance, it reduces the risk of developing dementia.
Physical activity is thought to have other beneficial effects related to cognition as it increases levels of nerve growth factors, which support the survival and growth of a number of
neuronal cells. Both aerobic and anaerobic exercise also work to increase the mechanical
efficiency of the heart by increasing cardiac volume (aerobic exercise), or myocardial thickness (strength training, see Organ hypertrophy).
Not everyone benefits equally from exercise. There is tremendous variation in individual
response to training: where most people will see a moderate increase in endurance from
aerobic exercise, some individuals will as much as double their oxygen uptake, while others
will never get any benefit at all from the exercise. Similarly, only a minority of people will
show significant muscle growth after prolonged weight training, while a larger fraction
experience improvements in strength. This genetic variation in improvement from training
is one of the key physiological differences between elite athletes and the larger population.
Exercise is a stressor and the stresses of exercise have a catabolic effect on the body contractile proteins within muscles are consumed for energy, carbohydrates and fats are
similarly consumed and connective tissues are stressed and can form microtears. However,
given adequate nutrition and sufficient rest to avoid overtraining, the body’s reaction to this
stimulus is to adapt and replete tissues at a higher level than what existed before exercising.
The results are all the training effects of regularly exercise - increased muscular strength,
endurance, bone density and connective tissue toughness.
Too much exercise can be harmful. The body part exercised needs at least a day of rest,
which is why some health experts say one should exercise every other day or 3 times a
week. Without proper rest, the chance of stroke or other circulation problems increases,
and muscle tissue may develop slowly. Inappropriate exercise can do more harm than good,
with the definition of “inappropriate” varying according to the individual. For many activities, especially running, there are significant injuries that occur with poorly regimented
exercise schedules.
In extreme instances, over-exercising induces serious performance loss. Unaccustomed
overexertion of muscles leads to rhabdomyolysis (damage to muscle) most often seen in
new army recruits. Another danger is overtraining in which the intensity or volume of training exceeds the body’s capacity to recover between bouts.
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Stopping excessive exercise suddenly can also create a change in mood. Feelings of depression and agitation can occur when withdrawal from the natural endorphins produced
by exercise occurs. Exercise should be controlled by each body’s inherent limitations. While one set of joints and muscles may have the tolerance to withstand multiple marathons,
another body may be damaged by 20 minutes of light jogging. This must be determined by
each individual.
Nutrition and recovery
Proper nutrition is at least as important to health as exercise. When exercising it becomes
even more important to have good diet to ensure the body has the correct ratio of macronutrients whilst providing ample micronutrients, this is to aid the body with the recovery
process following strenuous exercise.
Proper rest and recovery are also as important to health as exercise, otherwise the body
exists in a permanently injured state and will not improve or adapt adequately to the exercise. Hence, it is important to remember to allow adequate recovery between exercise sessions.The above two factors can be compromised by psychological compulsions (eating
disorders such as exercise bulimia, anorexia, and other bulimias), misinformation, a lack of
organization, or a lack of motivation. These all lead to a decreased state of health. Delayed
onset muscle soreness can occur after any kind of exercise, particularly if the body is in an
unconditioned state relative to that exercise.
3.1.5.2 Time management
Time management strategies are often associated with the recommendation to set goals.
These goals are recorded and may be broken down into a project, an action plan or a simple
task list. For individual tasks or for goals, an importance rating may be established, deadlines may be set and priorities assigned.
This process results in a plan with a task list or a schedule or calendar of activities. Authors
may recommend a daily, weekly, monthly or other planning periods, usually fixed, but
sometimes variable. Different planning periods may be associated with different scope of
planning or review. Authors may or may not emphasize reviews of performance against
plan. Routine and recurring tasks may or may not be integrated into the time management
plan and, if integrated, the integration can be accomplished in various ways.
A task list (also to-do list) is a list of tasks to be completed, such as chores or steps toward
completing a project. It is an inventory tool that serves as an alternative to memory. Task
lists are used in self-management, grocery lists, business management, project management, and software development. It may involve more than one list. When you accomplish
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one of the items on a task list, you check it off or cross it off.
The traditional method is to write these on a piece of paper with a pen or pencil, usually on
a note pad or clip-board. Numerous software equivalents are now available, and many popular e-mail clients include task list applications, as do most PDAs. There are also several
web-based task list applications, many of which are free.
3.1.5.3 Conflict resolution
Conflict resolution is the process of attempting to resolve a dispute or a conflict. Successful
conflict resolution occurs by listening to and providing opportunities to meet each side’s needs, and adequately address their interests so that they are each satisfied with the outcome.
Conflict Practitioners talk about finding the win-win outcome for parties involved, vs. the
win-loose dynamic found in most conflicts.
While Conflict resolution engages conflict once it has already started conflict prevention
aims to end conflicts before they start or lead to verbal, physical, or legal fighting or violence. Conflict itself has both positive and negative outcomes. Practitioners in the field of
Conflict Resolution aim to find ways to promote the postive outcomes and minimize the
negative outcomes. Conflict resolution processes can vary. However group conflict usually
involves two or more groups with opposing views regarding specific issues, often another
group or individual (mediator or facilitator) who is considered to be neutral (or suppressing
biases) in their opinion on the subject.
This last bit though is quite often not entirely demanded if the “outside” group is well respected by all opposing parties. Resolution methods can include conciliation, mediation,
arbitration or litigation. These methods all require third party intervention. A resolution
method which is direct between the parties with opposing views is negotiation.
Negotiation can be the ‘traditional’ model of hard bargaining where the interests of a group
far outweigh the working relationships concerned. The ‘principled’ negotiation model is
where both the interests and the working relationships concerned are viewed as important.
It may be possible to avoid conflict without actually resolving the underlying dispute, by
getting the parties to recognize that they disagree but that no further action needs to be taken
at that time.
In many cases such as in a democracy, a dialogue may be the preferred process in which
it may even be desirable that they disagree, thus exposing the issues to others who need
to consider it for themselves: in this case the parties might agree to disagree and agree to
continue the dialogue on the issue.
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3.1.5.4 Stress balls
A stress ball is a malleable toy, usually not more than 7cm in diameter. It is squeezed in
the hand and manipulated by the fingers, ostensibly to either help relieve stress and muscle
tension or to exercise the muscles of the hand. There are many types of stress balls. Many
are a closed-cell polyurethane foam rubber. This type of stress ball is made by injecting the
liquid components of the foam into a mold.
The resulting chemical reaction creates carbon dioxide bubbles as a byproduct, which in
turn creates the foam. Stress balls, especially those used in physical therapy can also contain gel of different densities inside a rubber or cloth skin. Another type uses a thin rubber
membrane surrounding a fine powder. The latter type can be made at home by filling a
balloon with baking soda. Some balls similar to a footbag are marketed and used as stress
balls. Despite the name, many stress balls are not spherical.
Many stress toys are molded in amusing shapes and screen or spot printed with corporate
logos. They are presented to employees and clients as gifts and marketing pieces. Stress
toys are a staple of cubicles where repetitive stress injuries such as carpal tunnel syndrome
are common. Because of the many shapes now available, stress balls are generically known
as stress relievers, and are a popular corporate promotional product.
3.1.5.5 Progressive relaxation
Progressive muscle relaxation is a technique of stress management developed by American
physician Edmund Jacobson in the early 1920s. Jacobson argued that since muscular tension accompanies anxiety, one can reduce anxiety by learning how to relax the muscular
tension. Jacobson trained his patients to voluntarily relax certain muscles in their body in
order to reduce anxiety symptoms.
He also found that relaxation procedure effective with ulcers, insomnia, and hypertension.
There are many parallels with autogenic training, which was developed independently.
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Relaxation steps
Sit in a comfortable chair – reclining arm chairs are ideal. Bed is okay too. Get as comfortable as possible – no tight clothes or shoes and don’t cross your legs. Take a deep breath; let
it out slowly. Again. What you’ll be doing is alternately tensing and relaxing specific groups
of muscles. After tension, a muscle will be more relaxed than prior to the tensing. Concentrate on the feel of the muscles, specifically the contrast between tension and relaxation. In
time, you will recognize tension in any specific muscle and be able to reduce that tension.
Don’t tense muscles other than the specific group at each step. Don’t hold your breath, grit
your teeth, or squint. Breathe slowly and evenly and think only about the tension-relaxation
contrast. Each tensing is for 10 seconds; each relaxing is for 10 or 15 seconds. Count “1,000
2,000...” until you have a feel for the time span. Note that each step is really two steps – one
cycle of tension-relaxation for each set of opposing muscles.
Do the entire sequence once a day until you feel you are able to control your muscle tensions. Be careful: If you have problems with pulled muscles, broken bones, or any medical
contraindication for physical activities, consult your doctor first.
1. Hands. The fists are tensed; relaxed. The fingers are extended; relaxed. 2. Biceps and
triceps. The biceps are tensed (make a muscle – but shake your hands to make sure not
tensing them into a fist); relaxed (drop your arm to the chair). The triceps are tensed (try to
bend your arms the wrong way); relaxed (drop them). 3. Shoulders. Pull them back (careful
with this one); relax them. Push the shoulders forward (hunch); relax. 4. Neck (lateral).
With the shoulders straight and relaxed, the head is turned slowly to the right, as far as you
can; relax. Turn to the left; relax. 5. Neck (forward).
Dig your chin into your chest; relax. (Bringing the head back is not recommended – you
could break your neck.) 6. Mouth. The mouth is opened as far as possible; relaxed. The
lips are brought together or pursed as tightly as possible; relaxed. 7. Tongue (extended
and retracted). With mouth open, extend the tongue as far as possible; relax (let it sit in
the bottom of your mouth). Bring it back in your throat as far as possible; relax. 8. Tongue
(roof and floor). Dig your tongue into the roof of your mouth; relax.
Dig it into the bottom of your mouth; relax. 9. Eyes. Open them as wide as possible (furrow
your brow); relax. Close your eyes tightly (squint); relax. Make sure you completely relax
the eyes, forehead, and nose after each of the tensings. 10. Breathing. Take as deep a breath
as possible – and then take a little more; let it out and breathe normally for 15 seconds. Let
all the breath in your lungs out – and then a little more; inhale and breathe normally for 15
seconds.
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11. Back. With shoulders resting on the back of the chair, push your body forward so that
your back is arched; relax. Be very careful with this one, or don’t do it at all. 12. Butt. Tense
the butt tightly and raise pelvis slightly off chair; relax. Dig buttocks into chair; relax. 13.
Thighs. Extend legs and raise them about 6in. off the floor or the foot rest but don’t tense
the stomach’ relax. Dig your feet (heels) into the floor or foot rest; relax.
14. Stomach. Pull in the stomach as far as possible; relax completely. Push out the stomach
or tense it as if you were preparing for a punch in the gut; relax. 15. Calves and feet. Point
the toes (without raising the legs); relax. Point the feet up as far as possible (beware of
cramps – if you get them or feel them coming on, shake them loose); relax. 16. Toes. With
legs relaxed, dig your toes into the floor; relax. Bend the toes up as far as possible; relax.
Now just relax for a while. As the days of practice progress, you may wish to skip the steps
that do not appear to be a problem for you. After you’ve become an expert on your tension
areas (after a few weeks), you can concern yourself only with those. These exercises will
not eliminate tension, but when it arises, you will know it immediately, and you will be able
to “tense-relax” it away or even simply wish it away.
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3.1.5.6 Autogenic training
Autogenic training is a relaxation technique developed by the German psychiatrist Johannes Schultz and first published in 1932. The technique involves the daily practice of sessions that last around 15 minutes, usually in the morning, at lunch time, and in the evening.
During each session, the practitioner will repeat a set of visualisations that induce a state of
relaxation.
Each session can be practiced in a position chosen amongst a set of recommended postures
(e.g. lying down, sitting meditation, sitting like a rag doll, etc.). The technique can be used
to alleviate many stress-induced psychosomatic disorders. Schultz emphasized parallels to
techniques in yoga and meditation. It is a method for influencing one’s autonomic nervous
system. Abbe Faria and Emile Coue are the forerunners of Schultz. There are many parallels to progressive relaxation.
Example of an autogenic training session:
sit in the meditative posture and scan the body
“my left arm is heavy and warm” (repeat 3 times)
“my arms and legs are heavy and warm” (repeat 3 times)
“my heartbeat is calm and regular” (repeat 3 times)
“my solar plexus is warm” (repeat 3 times)
...
finish part one by cancelling
start part two by repeating from steps 2 to cancelling
part three repeat steps 2 to cancelling
Quite often, one will ease themselves into the “trance” by counting to ten, and exit by
counting backwards from ten. This is another practice taken from progressive relaxation.
Effects of autogenic training Autogenic
Training restores the balance between the activity of the sympathetic (flight or fight) and
the parasympathetic (rest and digest) branches of the autonomic nervous system. This has
important health benefits, as the parasympathetic activity promotes digestion and bowel
movements, lowers the blood pressure, slows the heart rate, and promotes the functions of
the immune system.
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3.2 RECAP
• Which effect does stress have on health and performance?
• Explain “stress source” or “stressor”!
• List at least five stress symptoms!
• Give a definition of stress!
• Describe the connection between stress and performance!
• Which four stages of stress do you know?
• How can stress be managed?
3.3 REFERENCES
DRK Pain-Centre, Mainz (Germany): Method of developing “Stress sources and symptoms”
International Civil Aviation Organization (ICAO) (1998). Human Factors Training Manual,
Doc 9683-AN/950, Montreal
www.meb.uni-bonn.de/psychiatrie/medpsy/manuskripte/KursMedPsy5- 31.10.Stress.ppt :
Stress Performance Curve, retained Oct 24, 2007
http://www.thehealthcenter.info/adult-stress/types-of-stress.htm: Stress Definitions, retained Oct 24, 2007
http://www.mindtools.com/stress/UnderstandStress/StressPerformance.htm: Stress Performance Curve, Explanations, retained Oct 24, 2007
44
Teamwork
INDICE
ATCO BASIC TRAINING
HUMAN FACTORS
TRAINING DOCUMENT
Table of contents
4.
TEAMWORK
PAG. 48
4.1 Differences between social human relations
and professional interactions
4.1.1 Team
PAG. 49
4.2 Principles of teamwork
PAG. 49
4.3 Leader style and group interaction
5.3.1 Different leader styles
PAG. 52
PAG. 52
4.4 Recap
PAG. 53
4.5 References
PAG.53
PAG. 49
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4. TEAMWORK
Training objectives
L
Subj
Ref
1
Describe the differences between social human relations and
professional interactions.
2
HUM
5.4.1
2
Describe the principles of teamwork.
2
HUM
5.4.3
3
Describe the different types and characters in a team.
2
HUM
5.4.2
4
Describe leader style and group interaction.
2
HUM
5.4.4
L
CCC Level
Subj CCC subject abbreviation
Ref CCC reference code
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4.1 DIFFERENCES BETWEEN SOCIAL HUMAN RELATIONS
AND PROFESSIONAL INTERACTIONS
There are many situations where people do things together: shopping, talking, going out to
dinner, perhaps preparing dinner together and so on. But professional interactions are different: this is where teamwork is needed, especially in air traffic control.
Good teamwork is essential for safety. Social relationships are optional. You can leave if
you feel uncomfortable or unhappy with the relationship. Even in a non-professional team,
such as a football team you can leave if you no longer want to play football or if you feel
unhappy with the other players or with the team spirit or whatever.
Professional interactions are different: you cannot leave! You have to interact whether you
like it or not. The objective is a professional one. In air traffic the objective is to establish
respectively to preserve safety in the air and on the ground. Whether you get along well
with your colleagues or not, you always have to interact professionally.
4.1.1 Team
A team can be defined as a group of people – two or more people – who interact dynamically. Their interactions are dependent and they are trying to achieve a common goal. With the
team there are different tasks which need to be fulfilled. The team members have different
positions/functions and roles.
4.2 PRINCIPLES OF TEAMWORK
Group dynamics Teams develop according to the Forming-Storming-Norming-PerformingModel. The Forming – Storming – Norming – Performing model of team development was
first proposed by Bruce Tuckman in 1965, who maintained that these phases are all necessary and inevitable in order for the team to grow, to face up to challenges, to tackle problems,
to find solutions, to plan work, and to deliver results. This model has become the basis for
subsequent models of team dynamics and frequently used management theory to describe
the behavior of existing teams.
In the first stages of team building, the forming of the team takes place. The team meets and
learns about the opportunity and challenges, and then agrees on goals and begins to tackle
the tasks. Team members tend to behave quite independently. They may be motivated but
are usually relatively uninformed of the issues and objectives of the team. Team members
are usually on their best behaviour but very focused on themselves. Mature team members
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begin to model appropriate behaviour even at this early phase. Sharing the knowledge of
the concept of “Teams - Forming, Storming, Norming, Performing” is extremely helpful to
the team. Every group will then enter the storming stage in which different ideas compete
for consideration. The team addresses issues such as what problems they are really supposed to solve, how they will function independently and together and what leadership model
they will accept.
Team members open up to each other and confront each other’s ideas and perspectives. In
some cases storming can be resolved quickly. In others, the team never leaves this stage.
The maturity of some team members usually determines whether the team will ever move
out of this stage. Immature team members will begin acting out to demonstrate how much
they know and convince others that their ideas are correct. Some team members will focus
on minutiae to evade real issues.
The storming stage is necessary to the growth of the team. It can be contentious, unpleasant
and even painful to members of the team who are averse to conflict. Tolerance of each team
member and their differences needs to be emphasized. Without tolerance and patience the
team will fail. This phase can become destructive to the team and will lower motivation if
allowed to get out of control. At some point, the team may enter the norming stage.
Team members adjust their behaviour to each other as they develop work habits that make
teamwork seem more natural and fluid. Team members often work through this stage by
agreeing on rules, values, professional behaviour, shared methods, working tools and even
taboos. During this phase, team members begin to trust each other. Motivation increases as
the team gets more acquainted with the project.
Teams in this phase may lose their creativity if the norming behaviours become too strong
and begin to stifle healthy dissent and the team begins to exhibit groupthink. Some teams
will reach the performing stage. These high-performing teams are able to function as a unit
as they find ways to get the job done smoothly and effectively without inappropriate conflict or the need for external supervision.
Team members have become interdependent. By this time they are motivated and knowledgeable. The team members are now competent, autonomous and able to handle the decisionmaking process without supervision. Dissent is expected and allowed as long as it is
channelled through means acceptable to the team. (Wikipedia.com)
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Advantages of teamwork
The basic idea is: More people can achieve more. The advantages of teamwork are higher
efficiency because tasks can be shared among the group members. Problems can be solved
better because more ideas can be brought up. Errors can be identified by another team member which otherwise would not have been detected if the person had been working alone.
Therefore higher safety can be considered an advantage of teamwork in ATC.
Disadvantages of teamwork
Groupthink is a type of thought exhibited by group members who try to minimize conflict and reach consensus without critically testing, analyzing, and evaluating ideas. During
Groupthink, members of the group avoid promoting viewpoints outside the comfort zone of
consensus thinking. A variety of motives for this may exist such as a desire to avoid being
seen as foolish, or a desire to avoid embarrassing or angering other members of the group.
Groupthink may cause groups to make hasty, irrational decisions, where individual doubts
are set aside, for fear of upsetting the group’s balance. (Wikipedia.com)
Diffusion of responsibility is a social phenomenon which tends to occur in groups of people
above a certain critical size when responsibility is not explicitly assigned. This mindset can
be seen in the phrase “No one raindrop thinks it caused the flood”.
Examples for diffusion of responsibility are
• Kitty Genovese, a New York woman, was stabbed to death near her house. More than 30
of Genovese’s neighbours heard her screaming for help for approximately a half an hour,
yet no one helped her, each thinking that somebody else eventually would.
• In a firing squad, one of the shooters may be randomly issued a weapon containing a blank
cartridge rather than one with a bullet.
This allows each of the members of the firing squad to believe that he did not fire a fatal
shot. This phenomenon also applies to much more mundane circumstances, such as cleaning and maintenance of shared space/items or unassigned work in large organizations
getting neglected.
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Conflicts and solutions
Many conflicts within a team are role conflicts.
To identify the conflict it is important to look at the phase of the team. For example, communication problems more likely occur in the forming phase than in the phase of performing.
Groupthink however never occurs in the forming phase but needs a team which is used to
working together with established team structures and rules as well as norms.
Very often conflicts within a team are not being addressed openly because of the “team
spirit”. Team members don’t want to blame anyone else within their team. Safety-related
aspects are not addressed openly. This is neither a professional attitude nor a professional
behaviour. Conflicts have to be discussed openly in order to be able to solve them.
4.3 LEADER STYLE AND GROUP INTERACTION
In 1939 Lewin, Lippitt and White carried out their classic experiment which focused on the
behaviour of the leader instead of his or her personal character. The democratic leader style
turned out to be the most advantageous style. In this experiment school 10 and 11-year old
school children came together over a period of 12 weeks to play together once a week for
an hour. They were asked to do handicrafts. After six weeks the leader was changed as well
as the leader style. The interaction within the groups was observed and recorded.
4.3.1 Different leader styles
Autocratic style
The autocratic leader style is a very strict style with lots of control, orders and threats. In the
autocratic style, the leader takes decisions without consulting with others. The decision is
made without any form of consultation. In Lewin’s experiments, he found that this caused
the most level of discontent.
An autocratic style works when there is no need for input on the decision, where the decision would not change as a result of input, and where the motivation of people to carry out
subsequent actions would not be affected whether they were or were not involved in the
decision-making. In the experiment there was no understanding shown for the followers.
The pressure on the groups led to aggressive behaviour.
Everyone wanted to be noticed by the leader. The activity of the group depended very much
on the presence of the leader. As soon as he was not in the room, the group would stop working. If mistakes were made during the handicrafts the group would look for a scapegoat.
The individuals used the words “I and mine” very often. After the experiment the group did
not want to meet anymore under this leadership.
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Democratic style
The democratic style emphasizes tolerance and understanding. Measures which need to be
taken are discussed in the group. The atmosphere was friendly and cooperative. The group
members trusted each other more than under a authoritarian leader style. Whenever the leader was not present the group continued working on their tasks. The group would not look
for scapegoats in case of mistakes but took responsibility for the mistakes.
Laissez-faire style
During the laissez-faire style the leader does not give any orders. The group members can
do whatever they like. The group was very active but they were not able to reach the aim of
the task. The non-leadership was very often interrupted by informal leaders stepping out of
the group telling the other group members what to do.
This experiment influenced the research on leadership as well as the discussions on what is
the best way to lead a group a lot. However, we need to keep in mind that the experiment
was carried out with children. Not all the results can be transferred into the world of an air
traffic controller for example.
4.4 RECAP
• What is the difference between a group and a professional team?
• In your own words: define “team”!
• What are the characteristics of good teamwork?
• What are the advantages of teamwork?
• What is groupthink?
• Which disadvantages of teamwork may occur?
• Name three leader styles!
• In which way does the leader style influence the group interaction?
4.5 REFERENCES
Deutsche Flugsicherung GmbH (DFS):
SORT-Exercise created by Nanda Adam, 1999
International Civil Aviation Organization (ICAO) (1998).
Human Factors Training Manual, Doc 9683-AN/950, Montreal
www.wikipedia.com: Forming-Storming-Norming-Performing Model,
retained Nov 1, 2007
www.wikipedia.com: Groupthink, retained Nov 1, 2007
www.wikipedia.com: Diffusion of responsibility, retained Nov 1, 2007
53
Human Error
INDICE
ATCO BASIC TRAINING
HUMAN FACTORS
TRAINING DOCUMENT
Table of contents
5.
HUMAN ERROR
PAG. 58
5.1 The danger of error in ATC
PAG. 59
5.2 Human error
PAG. 59
5.3 Factors which help to cause error
PAG. 59
5.4 Error and violation
PAG. 60
5.5 Classification of human error
5.5.1 Skill based behaviour
5.5.2 Rule-based behaviour
5.5.3 Knowldege-based behaviour
5.5.4 Violations
PAG. 61
PAG. 61
PAG. 62
PAG. 63
PAG. 64
5.6 The Reason model
PAG. 65
5.7 Recap
PAG. 66
5.8 References
PAG. 66
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5. HUMAN ERROR
Training objectives
L
Subj
Ref
1
Recognise the dangers of error in ATC.
1
HUM
6.1.1
2
Define human error.
1
HUM
6.2.1
3
Describe the factors which help to cause error.
2
HUM
6.2.2
4
State the types of errors.
1
HUM
6.3.1
5
Define violations.
1
HUM
6.3.2
6
Differentiate between errors and violations of rules
2
HUM
6.3.3
7
Describe the three levels of performance according to the
Rasmussen model.
2
HUM
6.3.4
8
Describe the Reason Model
2
HUM
6.4.1
L
CCC Level
Subj CCC subject abbreviation
Ref CCC reference code
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5.1 THE DANGER OF ERROR IN ATC
There are many sources for errors and errors in ATC always endanger safety. Therefore we
will look at human error in more detail.
5.2 HUMAN ERROR
Human error is the failure of planned mental or physical activities to achieve their
intended outcome.
This definition has been taken from the book by James Reason “Human Error” (p. 9). It is a
working definition which has proved its utility in a psychological rather than a philosophical sense. It tries to embody the essential psychological characteristics of the phenomena
without struggling too hard to mark out their exact semantic boundaries.
The study of error, being largely an inductive mode of enquiry, does not demand precise axioms and definitions at the outset, as do the deductive sciences. It is to emphasize that we speak about error in relation to planned activities with an intended outcome.
We do not use the term “error” in relation to unintended actions or not-as-planned actions
(Reason1990, p. 8).
5.3 FACTORS WHICH HELP TO CAUSE ERROR
In order to fight the errors one first has to know the circumstances which favour them.
Such factors can be:
• Fatigue
• Lack of skill
• Workload
• Misunderstanding
• Lack of information
• Distraction
• Boredom
• Stress
• Lack of work satisfaction
• Health problems
• Loss of situational awareness
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5.4 ERROR AND VIOLATION
A slip describes an attentional failure such as intrusion, omission, reversal, misordering or
mistiming. A lapse is a memory failure. It occurs when you forget the intention, lose place
or omit planned items. Mistakes are known as rule-based or knowledge-based mistakes.
Knowledge-based mistakes can refer to all kinds of wrong knowledge which disturb the
proceedings from plan to intended action.
Rule-based mistakes mean either an application of a bad rule or a misapplication of a good
rule (Isaac & Ruitenberg 1999, p. 25). A violation is an active or deliberate set of actions
which are in contravention of the rules and mores of the organisation (Isaac & Ruitenberg
1999, p. 24). An example for the difference between an error and a violation of a rule: You
are driving on a street and the speed limit is 100 km/h. A violation: you know that the speed
limit is 100 and you are doing 120 because when you are caught it does not cost too much
and you don’t lose your license.
You always go a little faster than the speed limit. This would be a routine violation. If you
are in a hurry because your wife is about to have a baby and therefore you are doing 160 but
normally you keep the speed limit, then it is also a violation but an exceptional violation. It
is an error if you missed the sign which says 100. You didn’t see it. An attentional failure,
a slip. Or you did see the sign 5 minutes ago but you forgot! A memory failure, a lapse. I
might also be that there was no sign but it is a rule that on this kind of street the speed limit
is 100. But you have been applying a wrong rule. Then you have made a mistake, an application of a wrong rule.
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5.5 CLASSIFICATION OF HUMAN ERROR
The chart shows the Levels of Performance as developed by Rasmussen (1990). When the
situation is a routine situation, a situation which is expected and the task to be done is mainly automatic, the behaviour is a skill-based behaviour. When the situation is familiar or it is
a situation which on has been trained for and the task can be done conscious and automatic,
the behaviour is rule-based. When the situation is unknown, novel and the task needs all of
our attention, then the behaviour is knowledge-based.
5.5.1 Skill based behaviour
At the skill-based level, it can be seen that the types of activity are usually routine and automated, such as annotating flight strips. This type of behaviour tends to encourage errors
which are associated with attentional or memory failures. These include slips and lapses
and can be demonstrated by omitting information from the strip, annotating the strip in the
wrong place or forgetting what to annotate.
Attentional slips, in which we do not monitor our routine actions at critical points, often occur following a change in either our intentions or circumstances. The outcome is that we do
what is habitual in these circumstances rather than what is intended. This can be illustrated
after a runway change when controllers often keep using the old runway number in radio
transmissions. Memory lapses occur when we omit items in the action plan, or forget what
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we intended to do. Perceptual errors, in which objects and situations can be mis-recognised,
are the result of our expectations and habits. Examples here include flight crew indicating
that there are three green lights in response to a landing gear challenge, when in fact they
are red.
In Air Traffic Control the controller may assume that the same carrier and call sign arriving
at the same time is a certain weight category aircraft, when in fact the carrier is using a
different aircraft type. Also included in these error types are the various forms of disorientation that arise from our motion sensors in three-dimensional flight. Slips and lapses are the
problems faced by humans who do many of their actions in an automated way.
Normally the consequences of these errors are trivial, such as trying to open your front of
the door with your car keys. However the same type of error can be more serious depending
on the circumstances and environment. Turning the radio on instead of the compact disk is
just inconvenient, but hitting the wrong switch, such as the crash alarm instead of the runway lights, could be considered more serious.
5.5.2 Rule-based behaviour
At the rule-based level of activity, an individual uses certain types of response to known and
often rehearsed scenarios. For instance, in the flight situation standard operating procedures
would be classed as rule-based behaviour and in Air Traffic Control the use of separation
procedures and weather limits would also be classed as a similar type of activity. Rulebased mistakes involve the application of already known but inappropriate solutions to
problems that have been encountered many times before or which have been highly trained.
Rule-based mistakes can be divided into two types; the misapplication of good rules and
the application of bad rules. The misapplication of good rules is demonstrated in situations
where, during a problem solving exercise, the rules to be used are wrongly applied. This
can happen in situations that have many common features but in which there may be information which is not attended.
An example might be during a winter airfield inspection in which you brake to avoid a foreign object on the tarmac, forgetting the fact that the airfield surface is icy, and you slide
into a ditch. The application of bad rules is concerned with the use of poor problem solving,
which may have been picked up during training. They are considered bad because they may
be inadvisable or can lead to greater errors at a later date.
Examples may be found in radar when a trainee insists on always giving a flight level instruction before a heading direction irrespective of the situation or in radio transmission
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when flight numbers are used instead of both call sign and number. As can be seen the
two types of rule-based mistakes have different origins. The misapplication of good rules
evolves from the problems of failing to recognise the difference between appropriate and
inappropriate problem situations.
The difference between these two responses is hard to distinguish because we often apply
solutions to familiar problems with automatic pattern matching type responses. Bad rules
are developed through poor training or supervision and persist because the circumstances in
which they are used are often forgiving; rarely will they develop into an incident or accident.
5.5.3 Knowldege-based behaviour
Knowledge-based behaviour is the result of skill, ability, observation, training and experience. These variables will enable us to tackle novel, difficult or even dangerous situations with
adequate reliability and in most cases the likelihood of a successful outcome. In most cases
we are able to accomplish these successes through trial and error, although in Air Traffic
Control most will also have the benefit of long hours of strict training and supervision.
Some controllers will actively rehearse some of the more rare occurrences to be encountered, such as emergency calls, lost pilots or an accident in their airspace. In this way thy may
be able to handle such occurrences in a more systematic way, using problem solving techniques already known and familiar to them. Much of the success attributed to the recovery
from the catastrophic accident at Sioux City in 1989 was due to endless rehearsal of all the
emergency teams and the contingency plans which ware created by all the major groups at
and around the airport, including the Air Traffic Controllers.
In many cases the response to a knowledge-based situation can be managed at a rule-based
level depending on the circumstances. Knowledge-based mistakes occur when a person is
attempting to solve a novel problem; that is a person searching for a solution to a problem
which has not been previously encountered in training or experience. The main problems
with this situation are that a person is forced into a position of active reasoning and retrieval
from longterm memory which has an influence on the working-memory capacity.
There are also issues regarding the inaccurate use of mental models to support these problem solving activities. This type of reactive thinking is liable to several psychological
biases. Firstly, conformation bias, that is jumping to the wrong conclusion and then bending
the facts to fit these conclusions; secondly, frequency bias, a situation when frequently encountered possibilities are chosen despite conflicting information; thirdly, similarity bias,
the response of erroneously matching like situations; and lastly overconfidence.
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5.5.4 Violations
The last type of behaviour which should be mentioned is that of violation. This is an active
or deliberate set of actions which are in contravention of the rules and mores of the organisation. This behaviour can be seen in various ways and is often found, but not restricted, to
situations in which compliance goes unrewarded, there is little autonomy, there are unfair
sanctions, there is blame culture, poor supervisory standards and an adversarial industrial
climate (them and us).
Violations at a skill-based level often involve corner-cutting which is often the result of a
relatively indifferent environment, one which rarely rewards compliance or punishes violations. Violations at a rule-based level are associated with rules, regulations and safety
procedures, all of which are written to control behaviour in risky situations. As such there
are plenty of examples which can be found in the controlling situation.
When systems or technologies are initially introduced the procedures simply provide the
instructions for various tasks which are envisaged. These procedures, however, are continuously changing as the system becomes more familiar. Modifications are also incorporated into the system or technology as known problems emerge from various incidents.
The outcome is that the ability of the human to constantly work within the system is reduced as the system or technology develops. Because the range of actions necessary to be
used within the operational and commercial constraints may not reduce, the opportunity
for violations increases. This can be seen in the controlling environment when rules, which
usually have few if any negative consequences, are ignored or changed because of a perceived better way of operation.
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5.6 THE REASON MODEL
Latent conditions and active failures
The aim of air traffic control is to achieve safety. We have safety nets: procedures, rules,
professional attitudes, functioning equipment and professional know-how in order to avoid
incidents or accidents. In the model by James Reason these safety nets are symbolized by
the Swiss-Cheese-Slices. But not all systems are perfect. We all know that incidents happen.
This is because of the holes in the Swiss-Cheese. The holes in the Swiss-Cheese-Model
symbolize active failures – errors or violations– which trigger unwanted events but also
latent conditions which do not immediately trigger an incident. Let’s have an example:
A procedure has been in place for many years.The amount of traffic has increased but the
procedure was never adapted, which can be considered a latent condition.
The controllers adapted the procedure themselves which would be an active failure in this
case but this failure does not automatically mean that an incident occurs. It needs a combination of “holes” for an incident to occur. For example, maybe another error of a controller
or an error of a pilot. An incident or accident is the result of a combination of latent conditions and active failures.
This example also shows the combination of latent conditions and active failures. Latent
conditions can increase the likelihood of active failures. As a controller you usually don’t
always know all the decisions which have been made within your company and especially those in the top-management which do not effect your work directly. As an individual
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we are responsible for the safety of aircraft. This means that as soon as we feel that there
is anything which contradicts with our responsibility, e.g. a procedure, a rule or anything
which makes our work difficult for us, we should feel obliged to speak up and try to improve the conditions for everybody.
We should feel responsible for the whole system of air traffic control and not just for the
part of work which we are doing within the system. Coming back to the Swiss-Cheese- Model: whenever we recognize a hole, no matter where the hole is, we need to talk about it and
we need to find a way to fix it in order to increase the safety situation.
5.7 RECAP
• In your own words: Define human error!
• Describe the factors which help to cause error!
• State the different types of error!
• What is the difference between an error and a violation?
• In which situations do we show skill-based behaviour?
• Which behaviour do we show in complex and unknown situations?
• What is the connection between latent conditions and an accident?
• Describe latent conditions and active failures!
5.8 REFERENCES
Isaac, Anne R. / Ruitenberg, Bert: Air Traffic Control: Human Performance Factors.
Ashgate: Aldershot 1999
Reason, James: Human Error. Cambridge University Press: New York 1990
Reason, James: Education and debate. Human error: models and management, BMJ 2000;
320:768-770 ( 18 March )
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Communication
INDICE
ATCO BASIC TRAINING
HUMAN FACTORS
TRAINING DOCUMENT
Table of contents
6. COMMUNICATION
PAG. 70
6.1 Information requirement of ATC
PAG. 71
6.2 The importance of good communication
PAG. 71
6.3 Communication
PAG. 72
6.4 The Communication process
PAG. 72
6.5 Factors which affect communication
PAG. 73
6.6 Good communication practices
PAG. 74
6.7 Recap
PAG. 74
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6. COMMUNICATION
Training objectives
L
Subj
Ref
1
Explain the information requirement of ATC
2
HUM
7.2.8
2
Demonstrate the importance of good communications in ATC
2
HUM
7.1.1
3
Define communication
1
HUM
7.2.1
4
Define the communication process.
1
HUM
7.2.2
5
Describe the factors which affect verbal communication
2
HUM
7.4.1
6
Describe the factors which affect non-verbal communication
2
HUM
7.4.2
7
Apply good communication practices.
3
HUM
7.4.3
L
CCC Level
Subj CCC subject abbreviation
Ref CCC reference code
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6.1 INFORMATION REQUIREMENT OF ATC
Communication is a very important human factor aspect: It is THE media to transport information between Liveware and Liveware. Very much information is passed between the
pilot and the controller via verbal communication and between the controller and his colleagues via verbal as well as non-verbal communication.
6.2 THE IMPORTANCE OF GOOD COMMUNICATION
Communication is the strength of the human being over the systems. But because of the
risk of misunderstandings it can become dangerous. To avoid as many misunderstandings
as possible the information requirements of ATC are: pass relevant information only, pass it
timely and pass it accurately!
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6.3 COMMUNICATION
The word “communication” derives from the Latin word “communicare” which means to
share, to do together or to unite. Notice that it does not mean “to tell” or “to speak” – the
meaning of communication as we mainly use it today. The original meaning of the word
communication meant a joint action during which ideas, thoughts and knowledge was shared and created.
This meaning of communication or communicare you still find in the English word “community” which means that people are together, doing things, creating new ideas, making
plans etc. Also the word “communion” includes this original idea of a special sharing of an
idea. Communication can be defined as a process that allows organisms to exchange information by several methods.
6.4 THE COMMUNICATION PROCESS
The communication process begins with an idea which the transmitter or the sender wants
to pass on to somebody else, the receiver. The idea is in his head. To pass it on it is necessary to encode because we have to use our speech to pass on ideas between each other. The
transmitter wants to pass on the idea about a “tree” which is in his head.
He encodes “Tree”. This word is sent as a signal from the transmitters mouth to the receivers
ear. The receiver hears “Tree”. He has to decode the signal “Tree” to a picture in his head.
Whether this is the same picture as the sender has in his head remains unclear. One way of
making it clearer is the feedback. Feedback is again encoded information, either verbal or
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nonverbal, sent back to the original sender (now the receiver) which he has to decode again.
Communication can be seen as a constant process of encoding and decoding. Obviously
there is room for interferences and disturbances, called misunderstandings usually.
6.5 FACTORS WHICH AFFECT COMMUNICATION
Verbal communication
may be affected by:
Non-Verbal communication
may be affected by:
• Word choice
• Intonation
• Speed
• Tone
• Distortion
• Load
• Expectation
• Noise
• Interruption
• Language knowledge
• Accents
• Dialects
• Vocabulary
• Age, hierarchy
• expectation
• interruption
• misunderstandings of signals
• mood
• mimic art
• gestures not clear
• darkness
• too many people around
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6.6 GOOD COMMUNICATION PRACTICES
It is difficult to pass on information without changing details. Personal attitudes and thoughts have an influence on what you pass to your communication partner. Speaking and listening needs full concentration especially in a high risk environment like the ATM world.
Misunderstandings can be dangerous.
6.7 RECAP
• Name the three information requirements in ATC!
• Why is a timely and accurate communication of relevant information essential in ATC?
• In your own words: define communication!
• Describe the communication process!
• Why does the “code” sometimes cause communication problems?
• What is the purpose and advantage of “feedback”?
• Which factors may affect the communication process?
• How can we overcome communication problems?
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The Work Environment
INDICE
ATCO BASIC TRAINING
HUMAN FACTORS
TRAINING DOCUMENT
Table of contents
7.
WORK ENVIRONMENT
PAG. 78
7.1 The need for good building design
PAG. 79
7.2 Ergonomics
PAG. 80
7.3 Good working position design
7.3.1 Ergonomics and error
PAG. 81
PAG. 82
7.4 Automation
7.4.1 Reasons for Automation
7.4.2 Constraints of automation
PAG. 83
PAG. 83
PAG. 84
7.5 Recap
PAG. 85
7.6 References
PAG. 85
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7. WORK ENVIRONMENT
Training objectives
L
Subj
Ref
1
Be aware of the need for good building design
0
HUM
8.1.2
2
Define Ergonomics
1
HUM
8.1.1
3
Explain the need for good work position design
2
HUM
8.1.3
4
Characterise the equipment and tools that will be used in simulation
in accordance with the SHELL model.
2
HUM
8.2.1
5
Explain the reasons for automation
2
HUM
8.3.1
6
Describe the constraints of automation
2
HUM
8.3.2
L
CCC Level
Subj CCC subject abbreviation
Ref CCC reference code
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7.1 THE NEED FOR GOOD BUILDING DESIGN
Whether a building design is “good” or not depends on the individual purpose and the
perspective. Just think about the dilemma of street designers: wheelchair users prefer low
sidewalks to be able to get up and down easier, the sightless prefer high sidewalks because
they can recognizes them better with their cane.
The pictures show how such a compromise can be achieved: a tactile guiding system for the
sightless! Special design of the pavement allows the sightless to recognize that the sidewalk
is coming to an end and a street needs to be crossed.
Wheelchairs users have no difficulties crossing the streets either. In the ATM environment
there are not many wheelchair users and sightless people working. But the need for compromises between the various needs of different people is exactly the same. Compromises
have to be found which allow the controller to work safe and efficiently.
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7.2 ERGONOMICS
Ergonomics is the study of the principles of interaction between human and equipment, for the purpose of applying them in design and operations.
Ergonomics is a study subject. This means, ergonomists are people who are doing research.
They study the principles of interaction between human and equipment. They do not study
the interaction but the principles of the interaction. This means they are looking for the general idea behind the interaction between humans and machines and the general ideas of the
problems as well, of course. Having identified the principles, the results are used to design
systems which enable the human to work good, safe and efficient.
The purpose of the study ergonomics is to improve the work environment. It therefore is
a practical research. In many countries the terms “ergonomics” and “Human Factors” are
used interchangeably, but there is a small difference in emphasis. Human Factors has acquired a wider meaning, including aspects of human performance and system interfaces which
are not generally considered in the mainstream of ergonomics. Before a person-machine
system can be specified and designed system goals must be defined.
The goals, together with the identified operational constraints, spell out the conditions within
which the person-machine system will function. Operation of the system outside this set of
conditions may lead to unsafe conditions (ICAO 1998, 1-4- 3). An important task of the ergonomist is the allocation of functions and tasks to the human and machine components. The
system design team (including the ergonomist) decides what functions should be given to the
hardware and software and to the human, based on considerations such as human characteristics, task needs, workload, costs, training requirements, and technologies available.
Functions allocated inappropriately may jeopardize system effectiveness and safety. The
tendency to compare human and machine, in terms of the functions for which humans are
superior to machines vis-à-vis those for which machines are superior to humans, should
not be allowed to lead to a simplistic allocation of functions entirely to the human or the
machine. Humans and machines should be complementary in the accomplishment of tasks. Furthermore, this complementarity should be designed with adequate flexibility so that
function allocation can be adapted to various operational situations (from routine flight to
emergencies) (ICAO 1998, 1-4-3).
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7.3 GOOD WORKING POSITION DESIGN
It is essential for the controller to be able to reach all input devices without problems. It is as
well absolutely necessary to see all the displays in order to obtain the information provided
by the systems. If the chair is too high the radar screen cannot be seen. If it is too low the
touch input devices cannot be seen very well.
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7.3.1 Ergonomics and error
To minimize human error, one must first understand its nature. There are basic concepts
associated with the nature of human error: the origins and frequencies of errors can be
fundamentally different; and the consequences of errors can also be significantly different.
While some errors may be due to carelessness, negligence or poor judgement, many are
induced by poorly designed equipment or may result from the normal reaction of a person
to a stressful situation.
Errors due to poor equipment are likely to be repeated and can be remedied through the
practice of ergonomics. Each of the interfaces in the SHELL model has a potential for error
where there is a mismatch between its components. For example: The Liveware-Hardware
interface is a frequent source of error: knobs and levers which are poorly located or improperly coded create mismatches at this interface.
In the Liveware-Software interface, delays and errors may occur while seeking vital information from confusing, misleading or excessively cluttered documentation and charts.
Problems can also be related to information presentation and computer software design. In
the Liveware-Liveware interface, the focus is on the interaction between people because
this process may affect team and system effectiveness.
This interaction also includes leadership and followership. Shortcomings in these areas
may reduce operational efficiency and cause misunderstandings and errors. Considerations
which prevent errors such as these are in the mainstream of ergonomics.
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7.4 AUTOMATION
Automation refers to “a system or method in which many of the processes of production are
automatically performed or controlled by self operation machines, electronic devices, etc.”
(ICAO 1998, 1-3-9) Automation derives from the Greek and means “self-dictated”.
Automation can be defined as the replacement of human operators by machines. Automation is a step beyond mechanization which provided human operators with machinery to
assist them with the physical requirements of work, automation greatly reduces the need for
human sensory and mental requirements as well.
7.4.1 Reasons for automation
Why do we automate processes? What is the advantage? Machines can respond quickly to
control signals and are able to apply great force smoothly and precisely. They can perform
repetitive and routine tasks better than humans. Machines are able to store information briefly and to erase it completely as well. They can do many different things at once and they
can handle complex situations. Increased automation in aviation is inevitable.
The issue is therefore about when, where and how automation should be implemented, not
if it should be introduced. Properly used and employed, automation is a great asset. It can
aid efficiency, improve safety, help to prevent errors and increase reliability. This task is
to ensure that this potential is realized by matching automated aids with human capabilities and by mutual adaptation of human and machine to take full advantage of the relative
strengths of each.
In aviation automated systems, the human (pilot, controller, etc.), who is charged with the
ultimate responsibility for the safe operation of the system must remain the key element of
the system: automation or the machine must assist the human to achieve the overall objective, never the contrary. (ICAO 1998, 1-3-9).
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7.4.2 Constraints of automation
After looking at the positive aspects of automation we need to address the risks that come
along with the advantages as well: the constraints of automation.
High reliability may induce complacency
All forms of automated assistance for the human operator must be highly reliable, but this
may also induce complacency. Boredom and automation complacency may occur if a major
portion of air traffic management is completely automated, and human operators are lulled
into inattention. In the particular case of complacency, humans are likely to become so
confident that the automatic systems will work effectively that they become less vigilant or
excessively tolerant of errors in the system’s performance.
Human expertise may be lost
Human expertise may gradually be lost and if the machine fails, the human operator may accept an inappropriate solution or become unable to formulate a satisfactory alternative. The
most appropriate forms of human-machine relationship depend on the type of task which
is automated and particularly on the interaction between planning and executive functions.
Situational awareness might get lost
In the air traffic management environment, it is highly accepted that the performance of
routine ATC tasks aids memory, which is not the case if these tasks are done automatically
for the controller. Scientific studies have shown that, in order to form a mental picture of the
situation, controllers derive a lot of their situational awareness by speaking to the aircraft
and by making annotations on paper strips or making inputs (in more automated systems).
Verbal and written (or keyboard) inputs keep people “in the loop” and allow active updating
of the mental picture and situational awareness in its widest sense.
Deficiencies in human performance
It is believed that the automation of data can lead to deficiencies in human performance, since it can deprive the controller of important information about the reliability and durability
of information.
Loss of job satisfaction
Automation may well reduce the effort required to perform certain tasks and the stress
associated with them, but may lead to loss of job satisfaction by taking away some of the
intrinsic interest of the job and the perceived control over certain functions. Motivation and
job satisfaction involve problem areas such as loss of the controller’s feeling of importance, the perceived loss in the value of professional skills, and the absence of feedback about
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personal performance. Many operators feel that their main source of satisfaction in their
job lies in its intrinsic interest to them. They believe that the challenge of the job is one of
the main reasons they enjoy their profession. A takeover by automation to the point that job
satisfaction is reduced can lead to boredom and general discontent.
7.5 RECAP
• Why is it important to have a well designed working position?
• Define ergonomics!
• What does an ergonomist do?
• Which human-machine-interface problem can occur?
• Give an example for a human-machine-interface problem using the SHELL model!
• What are the advantages of automation?
• What are negative side effects of automation in ATM?
• Why should machines assist the human and not the other way around?
7.6 REFERENCES
http://www.graz.at/cms/beitrag/10026642/421969/: Pictures from Graz,
retained October 30, 2007, Stadtbaudirektion Graz - Referat Barrierefreies Bauen
International Civil Aviation Organization (ICAO) (1998).
Human Factors Training Manual, Doc 9683-AN/950, Montreal
85
INDEX
HUMAN FACTORS
TRAINING DOCUMENT
1. INTRODUCTION TO HUMAN FACTORS
PAG. 8
2. HUMAN PERFORMANCE
PAG. 18
3. STRESS
PAG. 28
4. TEAMWORK
PAG. 48
5. HUMAN ERROR
PAG. 58
6. COMMUNICATION
PAG. 70
7. THE WORK ENVIRONMENT
PAG. 78