49TH ANNUAL CONFERENCE, Punta Cana, Dominican Republic, 12-16 April 2010WP No. 161The Ageing ControllerPresented by PLC |
Summary
The WP looks into the influence of ageing on skills and performance of an ATCO. It contains an overview of mental and job performance and their changes whilst getting older, Furthermore, possibilities for how to decrease negative effects are shown.
Introduction
1.1 At the last conference (Dubrovnik 2009) PLC presented a working paper (WP) with the title „Review of Retirement Policy”. Despite the fact that some MAs are facing retirement age challenges PLC at that time did not see any reason to alter the general meaning and format of the existing policy. An MA presented a WP recommending the increase of the retirement age of ATCOs to 65. Committee C did not follow this recommendation. However, the question and reasons for considering earlier retirement of ATCOs have still remained unanswered.
1.2 For a more systematic approach to this subject, PLC decided to examine the influence of ageing on skills and performance of ATCOs. Consideration of potential benefits (experience) versus negative effects of ageing should be identified and necessary strategies to mitigate a probable decline in performance should be shown (Rybash, Roodin & Santrock (1991)).
Discussion
2.1 In 2003 and 2004 EUROCONTROL published two documents regarding ageing and ATM:
- “Age, Experience and Automation in European Air Traffic Control“
- “Age, Experience and Automation in European Air Traffic Control – Survey in the ECAC Area“.
Most of the content in this part of the WP is based on the EUROCONTROL documents.
2.2 Ageing
2.2.1 Ageing as part of a natural process is a complex mixture of factors (physiological, social, cultural factors). Age can be distinguished (Rabbitt (1994); Stuart-Hamilton (1994)):
- chronologically – numbers of years since birth
- biologically – functional capacity of the vital organ system
- psychologically – ability to adapt to changing demands in environment
- functionally – ability to function effectively within a given environment
2.2.2 Focusing on the negative aspects of getting older the western societies usually associate old age with deterioration and decline. Other cultures connect it with attributes like maturity, wisdom, or calmness.
2.2.3 Obviously there are not only downsides to getting older but also gains like gathering of experience, knowledge and skills. The balance between both sides influences the performance of ATCOs, especially over the age of 40. ATCOs over forty might feel more impact because of increasing air traffic and major changes in technical equipment, in procedures, and in airspace organisation than their younger colleagues. But it is possible to support them to keep up the required professional level as long as possible.
2.3 Neurological effects
2.3.1 Air traffic control is always a perceptive-cognitive activity. “Perceptive“ stands for the ability to see, hear, or become aware of and interpret something. These are mental impressions based on neurophysiological processes, including memory. “Cognitive“ means mental actions or processes of acquiring knowledge and understanding through thought, experience, and the senses.
2.3.2 With increasing age physiological changes are happening to our central nervous system (i.e. in our brain) strongly influencing the functions of our brain and consequently our mental performance.
2.3.3 The human brain consists of about five thousand millions brain cells called neurons. Via dendrites – “wires“ for linking neurons to each other to pass “messages“ – they transmit electrophysiological and chemical impulses. New connections with each other are formed through growing new dendrites. Such networks can be regarded as the biological basis of mental processes like information storage in the brain.
2.3.4 Unfortunately neurons cannot reproduce themselves by cell division. That means with ageing their number will decrease. Furthermore the surviving nervous cells begin to incorporate deposits of proteins. The number of dendritic connections to other neurons decreases. Specific patterns of change for some neurotransmitter systems, which transmit nervous impulses chemically, are another observed mutation in relation to ageing.
2.3.5 All these lead to decreased efficiency of the brain in transmission of nervous impulses. Reaching a certain level mental performance will begin to show impairments like memory problems (Craik (1994); Birren & Schaie (1985); Stuart-Hamilton (1988)).
2.4 Mental Performance
2.4.1 Signal detection of visual or auditory signals, attention, memory, spatial reasoning and problem solving/decision-making are all mental performances being of high importance for the profession of ATCOs. Unfortunately ageing more or less influences them all negatively.
2.4.2 Not only does eyesight deteriorate with age but also dark adaptation. One will be faced with difficulties following moving objects, and the increasing sensitivity of glare and increasing recovery time after glare exposure. Regarding hearing it is important to know for ATCOs that understanding speech sound in a noisy environment gets less with increasing age.
2.4.3 Capacity of attention is never unlimited. But this capacity seems to decrease with age. However “growing old” influences the different kinds of attention differently (Rybash, Roodin & Santrock (op. cit.); Kline & Scialfa (op. cit.)). Divided attention of older people remains stable compared to that of younger people as long as complexity of the tasks to be performed is not increasing. Sustained attention appears to decrease, with performance decrements over a longer period of time as a consequence. That can be improved to the level of younger colleagues by short breaks (5 min.) in certain time intervals (Thackray & Touchstone (1982)). Regarding selective attention it has been stated that older people have more difficulties to discriminate between relevant and irrelevant information. With high similarity of information and noise as a distraction factor, these difficulties still increase further. Practice or experience lead to an automatic information processing, demanding little attentional capacity. Therefore this kind of information processing does not change during life. Difficult information processing, for example tasks that demand selection and sequencing aspects of attention, or tasks that are especially time-consuming, require a great deal of attentional capacity and will decline with age.
2.4.4 Memory can be divided into three different kinds of memory with separated and different functions. The „sensory store“ as a first filter works totally unconsciously. It checks the relevance of incoming information in only milliseconds and is hardly affected by age. If the information is attracting attention it enters the “short-term memory“. While its capacity is barely affected by age its dynamics is. Performance of the working memory which selects, coordinates and processes incoming information, especially its speed, declines substantially after the age of sixty (Salthouse (1994); Craik (1994)). Tasks with high demand on working memory like more complex tasks and tasks process information in parallel (multitasking) are performed disproportionately worse by older people. The “long-term memory“ will be reached by relevant information after some minutes of processing by the “short-term memory“. This part of the memory obviously decreases with getting older. But the nature of the memory test, the learning strategy, the material to be remembered and characteristics of the learner have an influence on the extent of the decline (Rybash, Roodin & Santrock (1991)). Memory testing can be done in two ways: recognition or free recall.
On this occasion free recall means to call to mind directly as much as possible former learned material. Recognition is a way to remember previous learned material with the help of selection (e.g. a list which contains more than the previous learned items). Across all age groups performance in recognition is much higher than those in free recall. Free recall task memory performance of older people diminishes whereas in recognition almost no age differences are shown. With beneficial learning strategies like organisation, semantic elaboration and mental imagery it is possible to equalize the decrease in free recall performance. Furthermore familiarity and meaningfulness of the items to be remembered is very important for memory performance in older people. And last but not least attitudes, interests, health-related factors, intelligence level and the amount of previously acquired knowledge and skills of the person remembering have a great impact on memory performance.
2.4.5 Spatial visualisation being of high importance for the profession of ATCOs slows down with increasing age. On average, processing of spatial information like perspective-taking, mental rotation of objects, spatial memory, or environmental learning task, will be slower and less accurate compared with that of younger people. These effects can be observed in a novel setting and when abstract components are involved in the tasks. They are reduced or even completely removed by tasks with concrete material and familiar context. The same situation exists in regard to problem solving. Older persons are less efficient in solving problems in unfamiliar domains because of impaired working memory. Especially when regarding complex problems, performance deteriorates disproportionately when complexity increases even though that reduction generally does not start before the age of sixty of even seventy. On the other hand there is hardly any impairment of efficiency and quality due to increased age when older people are requested to solve a problem in their domain of expertise (Charness (1985); Glaser (1994)). Obviously basic processes, underlying information processing and problem solving which are necessary for solving new and unfamiliar problems (mechanical intelligence) declines with increasing age. However skills and knowledge-related aspects like factual knowledge and knowledge regarding strategies (pragmatic intelligence) needed for solving well-known and familiar problems grow with age.
2.5 Job Performance
2.5.1 It is almost impossible to assess job performance in general. To master a domain it is necessary to learn a great number of specific facts and procedures. It takes about ten years of intensive preparation and practice to reach an expert level of performance. This experience seems to be a better predictor for job performance than age (Davies, Matthews & Wong (1991); Welford (1985)). But it is possible to identify some common trends in the relationship between age and job performance. Components such as concentration, some aspects of attention and most of long-term memory will show no change with age at all (Behrend (2000)). Proficiency, exactness, experience, faculty of judgement, reliability, sense of responsibility and knowledge of company and their procedures will be increased. For muscular strength, movability, vision and hearing, flexibility, speed of information processing, speed of reactions and working memory a decrease has to be expected. Consequently older employees will try to leave jobs which place high physical demand or high time stress on them. Production records show an inverted U-shaped relationship with age for skilled and semi-skilled workers, with peak performance mostly between the mid- thirties and the early forties whereas such a decline in performance for sales and office work is not obvious.
2.5.2 Expertise meaning knowledge and skills of well-experienced operators is mainly characterized by structured, principled knowledge, proceduralised knowledge, skilled memory, automaticity, effective problem representation and strong self- regulatory skills. Apparently expertise provides a benefit for ageing employees in a sense of compensating declines in mental abilities.
2.6 Job performance of ATCOs
2.6.1 While some older studies conducted in the US indicated a negative relationship between age of ATCOs and their job performance the latest one came to a converse result (Nunes, Kramer (2009)). But unfortunately these studies only took into account relatively isolated tasks of the job. If the requirements of the whole work situation is not fulfilled, it will not be possible to assess the overall work strategies (e.g. prioritisation of tasks, workload management, risk-taking behaviour, etc.). Moreover, all the expert knowledge in terms of contextual conditions related to a certain sector is not asked in such simulator-based tests. To draw well-founded conclusions on the relationship between age of ATCOs and job performance it is necessary to research not only a few selected aspects but also more natural situations within the entire context of ATC.
2.6.2 Nevertheless, taking into account the statements of the preceding chapters we may expect different developments regarding cognitive skills of ATCOs in relation to ageing:
1. Cognitive skills that are likely to decline
- multitasking,
- direct attention to information source,
- manage working memory,
- active problem solving,
- diagnose novel situations/problems
2. Cognitive skills that are likely to improve
- take account of and process external information,
- monitoring,
- build up mental picture of traffic situation,
- develop a plan,
- maintain situational awareness,
- make decision for control actions,
- diagnose perceived problem,
- awareness of team situation,
- team multitasking,
- establish mental picture of situation during takeover.
3. Cognitive skills remaining neutral
- integrate into long-term memory,
- active planning,
- solve aircraft conflict,
- manage requests and assist pilots,
- team working,
- share mental picture of traffic situation during handover.
2.6.3 Important when considering ageing, are only those cognitive skills, which will be affected in a positive or negative way by age and experience. Countermeasures to cope with ageing should be developed for the five skills that are likely to decline. The ten skills that are expected to improve could be a tool to tackle ageing-related problems.
2.7 Mitigation strategies regarding ageing in ATM
2.7.1 Retirement
2.7.1.1 An early retirement age for ATCOs is a tool to avoid their employment in a time where a significant deterioration of the declining cognitive skills may be expected. It is IFATCA-policy that for active air traffic controllers the age of retirement should be closer to 50 than 55. But only a few States follow this recommendation. In some of the States there is no difference between legal retirement age and retirement age of ATCOs. Moreover, in States which have currently an earlier retirement age for ATCOS, ANSPs often attempt to raise this age because of demographic shift in general, the lack of ATC-personnel worldwide and because pension systems are stretched to their limits. Even for this IFATCA has strong policy:
| “ANSPs must not increase retirement ages in an attempt to address ATCO staff shortage issues.“ (TPM 4151) |
2.7.1.2 To maintain the high level of safety in aviation is one of the main reasons for terminating operational work of ATCOs. Personal limits could arise with increasing age. Denying these limits either by management or by the ATCO itself could have serious consequences on safety. Therefore appropriate procedures should be in place especially in States with retirement ages over 55 years to assess the suitability of ATCOs in connection with nature and scope of their assignment and the technical equipment of their working positions. These procedures should contain not only at least yearly medical examination but also adequate proficiency checks and checks of mental performance.
2.7.2 Training
2.7.2.1 Regular and frequent refresher training can help to maintain skills sufficient even at greater age. That is especially important to support older controllers in dealing with the unexpected in their day-to-day work.
2.7.2.2 A basic requirement regarding transition training for the implementation of new equipment is that each controller receives the training time he or she needs. Computer-based Training (CBT) tools e.g. allow each ATCO to spend as much time as necessary.
2.7.2.3 As self-awareness about one own limit is crucial for a safe working behaviour, ATC-training addressing the issue of ageing should be made available directly in a training course.
2.7.3 Career development
2.7.3.1 A systematic approach to ATCOs career development is rarely to be found within the different ANSPs. But controllers need clear and achievable alternatives to operational work in case they cannot cope with the demand for whatever reason.
2.7.3.2 The constantly increasing traffic load, the more and more demanding night shifts, health problems or other grounds may lead to a need for medium- to long-term alternatives to the operational job. Preferably, older controllers should have the opportunity to find positions appropriate to their competency. That means not only the transition between several ATC services but also to switch from an operational position like executive controller to another operational position like coordinating controller, or from more demanding sectors/positions to less demanding ones.
2.7.3.3 Involvements in tasks like training, supervisory, managerial or administrative tasks, and performance assessment, selection of personnel, incident investigation and technological system are another way to minimise the strain of the ops room.
2.7.4 Working hours
2.7.4.1 The negative impacts of shift work on health and well-being are intensified by ageing so that the combination of both can become health-critical. This should be taken into consideration regarding the medical status of older ATCOs. Even if it is not possible as an ATCO to avoid working shift time, there should be a reduction in the number of night shifts as controllers become older.
2.7.4.2 Keeping in mind that mental capacity can be improved to the level of younger colleagues by short breaks; a change in break patterns for older employees seems to be beneficial. Older colleagues should take breaks more often, but of shorter duration than younger ones.
2.7.4.3 Taking into account the age of colleagues when allocating work positions is another way to show consideration regarding ageing.
2.7.5 Workplace design
2.7.5.1 As working memory is a vulnerable area regarding ageing, well-developed technological equipment should provide a support for it. Tasks requiring a lot of resources from working memory like the five declining cognitive skills of ATCOs could be relieved by aide memoirs. The automation of complex mental processes but even more simple tools like acoustic or visual reminders could be a contribution. Development of support tools for active problem solving and situation diagnosis could assist the planning process and limit the number of unexpected events. To compensate for the decrease in speed of older ATCOs input features should be as simple and timesaving as possible.
2.7.5.2 Human Machine Interfaces (HMI) issues like font size, the use of colour screens and contrasts on the screen and usability of the equipment are also important with regard to older colleagues. Regarding lighting, older ATCOs will prefer ops rooms with daylight. During night-time or for ops rooms without daylight adjustable light source for every workplace should be available.
2.7.5.3 Hearing can also decrease with ageing. Noise lowering floors and adjustable auditory information sources may help to minimise background noises.
2.7.5.4 All ATCOs should have easy access to information sources. That is even more important for the older controller, because the ageing body is less tolerant regarding twisting or stretching the body. Therefore chairs and consoles should also be individually adaptable.
2.7.5.5 In general representatives of older ATCOs should be involved in the design phase of new equipment. This would not only help to increase the acceptance of new techniques or procedures by this group but also to build into new systems their experience.
Conclusions
3.1 Ageing is a natural process with a complex mixture of factors. It is associated not only with negative aspects like deterioration and decline but also with positive ones like maturity, wisdom or calmness. Both sides of ageing and their interaction have a substantial impact on performance of ATCOs between the age of 40 and 65.
3.2 The relationship between age and job performance in ATC has not yet been researched sufficiently until now. Only relatively isolated tasks of the job had previously been investigated. These studies came to opposite results. It seems obvious that experience can compensate declines in mental abilities and cognitive skills up to a certain point. To draw solid conclusions on the relationship between age of controllers and job performance more research, taking into account the entire ATC work situation is needed.
3.3 Cognitive skills of ATCOs that are likely to improve by ageing:
- take account of and process external information,
- monitoring,
- build up mental picture of traffic situation,
- develop a plan,
- maintain situational awareness,
- make decision for control actions,
- diagnose perceived problem,
- awareness of team situation,
- team multitasking,
- establish mental picture of situation during takeover
could be a tool to tackle ageing-related problems.
3.4 Countermeasures to cope with the cognitive skills that are likely to decline:
- multitasking,
- direct attention to information source,
- manage working memory,
- active problem solving,
- diagnosed novel situations/problems
should be developed.
3.5 An early retirement age of ATCOs is a tool to avoid their employment in a time where a significant deterioration of the declining cognitive skills may be expected. In States without earlier retirement ages for ATCOs procedures should be in place with at least yearly medical examination, adequate proficiency checks and checks of mental performance after the age of 55.
3.6 ANSPS should offer career development plans as medium- to long-term alternatives to the operational job.
3.7 Training courses for ATCOs regarding the effects of ageing should be established.
3.8 For healthcare of older ATCOs the number of night shifts after the age of 50 shall be reduced to a minimum. The mental capacity of older controllers can be improved by breaks which should be more often but of shorter duration than for younger colleagues. Another possibility is to reduce the number of ratings after a certain age.
3.9 Because older ATCOs have other needs regarding the design and equipment of new procedures or technologies than the younger ones, representatives of the older age group should be involved in all development phases of new systems.
Recommendations
New policy to be added on page 4136 new Para 3.7: Ageing ATCOs:
4.1 ANSPS should offer career development plans as medium- to long-term alternatives to the operational job.
4.2 Training courses for ATCOs regarding the issue of ageing should be made available.
4.3 ATCOs with an age of 50 years or older shall be entitled to abstain from nightshifts on their request.
4.4 Ageing ATCO’s should be entitled to additional short breaks to assist in their performance with short-term memory.
4.5 Ageing ATCOs should be entitled to reduce the number of their ratings to a reasonable minimum.
References
HRS/HSP-005-REP-02 “Age, Experience and Automation in European Air Traffic Control”,
HRS/HSP-005-REP-05 “Age, Experience and Automation in European Air Traffic Control – Survey in the ECAC Area“.
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Last Update: September 29, 2020