Aviation Australia Memory, Claustrophobia and Physical Access PDF

Memory, Claustrophobia and Physical Access (9.2.5-6) Learning Objectives 9.2.5 Describe the aspects of memory and explain common barriers to remembering (Level 2). 9.2.6.1 Explain claustrophobia and describe situations/locations in which aircraft maintenance workers may suffer clau...

Memory, Claustrophobia and Physical Access (9.2.5-6) Learning Objectives 9.2.5 Describe the aspects of memory and explain common barriers to remembering (Level 2). 9.2.6.1 Explain claustrophobia and describe situations/locations in which aircraft maintenance workers may suffer claustrophobia (Level 2). 9.2.6.2 Explain physical access and describe situations/locations in which aircraft maintenance workers may experience restricted physical access (Level 2). 2023-01-12 B-09 Human Factors Page 73 of 340 CASA Part 66 - Training Materials Only  Memory Summary Memory is critical to our ability to act consistently and to learn new things. Without memory, we could not capture the constant stream of information reaching our senses. Without memory, we could not draw on past experience and apply this knowledge when making decisions. Memory can be considered the storage and retention of information, experiences and knowledge, as well as the ability to retrieve this information. Memory Processes Memory depends on three processes: Registration - the input of information into memory Storage - the retention of information Retrieval - the recovery of stored information. Image by Andrea Piacquadio from Pexels Memory can be considered the storage, retention and retrieval of information 2023-01-12 B-09 Human Factors Page 74 of 340 CASA Part 66 - Training Materials Only  Types of Memory It is possible to distinguish among three forms of memory: Ultra-short-term memory (or sensory storage) Short-term memory (often referred to as working memory) Long-term memory. Ultra-Short-Term Memory We described ultra-short-term memory when we examined the role of sensory stores. It has a duration of up to 2 seconds (depending on the sense) and is used as a buffer, giving us time to attend to sensory input. Short-Term Memory Short term memory receives a proportion of the information gathered into sensory stores and allows us to store information long enough to use it (hence the idea of ‘working memory’). It can store only a relatively small amount of information at one time, 7 ± 2 items of information, for a short duration, typically 10 to 20 seconds. The duration of short-term memory can be extended through rehearsal (mental repetition of the information) or encoding the information in some meaningful manner, to aid in recalling the information. Image by Glen Carrie on Unsplash Short term memory can store about 7 ± 2 items of information for about 10 to 20 seconds 2023-01-12 B-09 Human Factors Page 75 of 340 CASA Part 66 - Training Materials Only  Long-Term Memory The capacity of long-term memory appears to be unlimited. It is used to store information that is not currently being used, including: Knowledge of the physical world and objects within it and how these behave Personal experiences Beliefs about people, social norms, values, etc. Motor programs, problem solving skills and plans for achieving various activities Abilities, such as language comprehension. Information in long-term memory can be divided into two types: Semantic memory is our store of general, factual knowledge about the world, such as concepts, rules, one’s own language, etc. It is information that is not tied to where and when the knowledge was originally acquired. Episodic memory relates to memory of speci c events, such as our past experiences (including people, events and objects). We can usually place these things within a certain context. It is believed that episodic memory is heavily in uenced by a person’s expectations of what should have happened. Thus, two people’s recollection of the same event can differ. © Aviation Australia Memory structure 2023-01-12 B-09 Human Factors Page 76 of 340 CASA Part 66 - Training Materials Only  Motor Programs If a task is performed often enough, it may eventually become automatic and the required skills and actions will be stored in long-term memory. These are known as motor programs and are ingrained routines that have been established through practice. The use of a motor program reduces the load on the central decision maker. An often-quoted example is that of driving a car. At rst, when learning to drive, each individual action such as gear changing and indicating is demanding, even overwhelming. But eventually the separate actions are combined into a motor program and can be performed with little or no awareness. These motor programs allow us to carry out simultaneous activities, some almost unconsciously, such as having a conversation while driving. Image by MikesPhotos from Pixabay Motor programs and are ingrained routines that have been established through practice Situational Awareness in Aircraft Maintenance The process of exercising attention, perception and judgement should result in awareness of the current situation. Situational awareness is the synthesis of an accurate and up to date 'mental model' of one's environment and state, and the ability to use this to make predictions of possible future states. Like the example of driving a car, situational awareness has often been used in the context of the ight deck to describe pilots' awareness of what is going on around them, e.g. where they are geographically, their orientation in space, how the aircraft is ying, etc. 2023-01-12 B-09 Human Factors Page 77 of 340 CASA Part 66 - Training Materials Only  In the maintenance engineering context, it refers to: The perception of important elements, e.g., seeing loose bolts or missing parts, hearing information passed verbally. The comprehension of their meaning, e.g., why is it like this? Is this how it should be? The projection of their status into the future, e.g., future effects on safety, schedule, airworthiness. An example of situational awareness is an aircraft maintenance worker seeing blue streaks on the fuselage of an aircraft. Their comprehension may be that a lavatory ll cap could be missing or the drain line leaking, allowing the lavatory ush liquid to leak from the servicing panel and stain the fuselage. If their situational awareness is good, they may appreciate that such a leak could allow the blue ush liquid to freeze, which may lead to airframe or engine damage, or damage to property on the ground, if the build-up of ice falls from the ying aircraft. As with decision-making, feedback improves situational awareness by informing us of the accuracy of our mental models and their predictive power. The ability to project system status backward, to determine what events may have led to an observed system state, is also very important in aircraft maintenance engineering, as it allows effective fault nding and diagnostic skills. Situational awareness for the AME can be summarised as awareness of: The status of the system the AME is working on The relationship between the reported defect and the intended recti cation The possible effect of this work on other systems The effect of this work on that being done by others and the effect of their work on this work. This suggests that in aircraft maintenance, the entire team needs to have situational awareness, not just of what they are doing individually, but of their colleagues’ activities as well. 2023-01-12 B-09 Human Factors Page 78 of 340 CASA Part 66 - Training Materials Only  Image by Mason Dahl on Unsplash In aircraft maintenance, the entire maintenance team needs to have situational awareness 2023-01-12 B-09 Human Factors Page 79 of 340 CASA Part 66 - Training Materials Only  Information Processing Limitations It is important to appreciate that human information processing has limitations. As a consequence, the aircraft maintenance engineer, like other skilled professionals, require on-going support for their perception and memory. Most important is a reference to written material, such as manuals and other approved data. Image by Marcus Spiske from Pexels Human information processing has limitations 2023-01-12 B-09 Human Factors Page 80 of 340 CASA Part 66 - Training Materials Only  De ciencies in Attention and Perception A proportion of sensed data may be lost without being fully perceived. An example with which most people are familiar is that of failing to listen well enough and then trying to perceive accurately what someone has said. This usually occurs when a person is concentrating on something else, even though the words would have been received at the ear without any problem. The other side of the coin is the ability of the information processing system to perceive something (such as a picture, sentence, concept, etc.) even though some of the data may be missing, or in an unusual con guration, like upside-down. The danger, however, is that people can ll in the gaps with information from their own store of knowledge or experience, and this may lead to the wrong conclusion being drawn. © Aviation Australia Information processing system can perceive something even though some of the data may be missing 2023-01-12 B-09 Human Factors Page 81 of 340 CASA Part 66 - Training Materials Only  Biases and Expectations Once people have formed a mental model of a situation, they often seek information which will con rm this model and, unconsciously, reject information which suggests that this model is incorrect. In aviation maintenance it is often necessary to consult documents with which the engineer can become very familiar. It is possible that a maintenance worker can scan a document and fail to notice that subtle changes have been made. They may see only what they expect to see (expectation). To illustrate how our eyes can deceive us when quickly scanning a sentence, read the sentence below quickly. © Aviation Australia People may they often seek information which will con rm to a model At rst, most people tend to notice nothing wrong with the sentence. Our perceptual system sub- consciously rejects the additional “the”. 2023-01-12 B-09 Human Factors Page 82 of 340 CASA Part 66 - Training Materials Only  Another example: Source: Trends in Cognitive Science People may consistently seek information which will con rm to a model Expectation can affect judgement, which is a dangerous situation for a profession in which many inspections are carried out. If an aircraft maintenance worker conducts tens or hundreds of pre- ight inspections on the same aircraft type and never nds anything wrong, then their expectation may be that they will never nd anything wrong on a pre- ight inspection. This may mean that, over time, their diligence in conducting pre- ight inspections diminishes. Thus, expectation can aggravate complacency. To combat complacency, maintenance workers need to remind themselves that the next time they conduct a pre- ight inspection may be the very time they nd a defect which affects the safety of the ight. There are many well-known visual ‘illusions’ which illustrate the limits of human perception. The gure below shows how the perceptual system can be misled into believing that one line is longer than the other, even though a ruler will con rm that are exactly the same. © Aviation Australia The Muller-Lyer Illusion The gure below illustrates that we can perceive the same thing quite differently (i.e., the letter “B” or the number “13”). This shows the in uence of context on our information processing. 2023-01-12 B-09 Human Factors Page 83 of 340 CASA Part 66 - Training Materials Only  The importance of context - This gure illustrates that we can perceive the same thing quite differently (i.e., the letter “B” or the number “13”) 2023-01-12 B-09 Human Factors Page 84 of 340 CASA Part 66 - Training Materials Only  Memory Limitations Attention and perception shortcomings can clearly impinge on decision-making. Perceiving something incorrectly may lead us to make an incorrect decision, resulting in an inappropriate action. Sensory and short-term memories have limited capacity and duration. It is also important to bear in mind that human memory is fallible, so that information: May not be stored. May be stored incorrectly. May be dif cult to retrieve. All these results of our limitations may be referred to as forgetting, which occurs when information is not stored in the rst place or cannot be retrieved. Information in short-term memory is particularly susceptible to interference, for example, trying to remember a part number while also trying to recall a telephone number. Image by Andrea Piacquadio from Pexels It is also important to bear in mind that human memory is fallible 2023-01-12 B-09 Human Factors Page 85 of 340 CASA Part 66 - Training Materials Only  The Danger in Relying on Memory in Aircraft Maintenance It is essential to use approved data rather than to rely upon memory, even in circumstances when the information to be remembered or recalled is relatively simple. For instance, an AME may think they will remember a torque setting without consulting the manual. But they may not remember correctly, or they may confuse it with a different torque value for a similar task. Another possibility is that the torque setting has been amended by the manufacturer and the approved manual changed. If the AME does not regularly consult the manual and relies on memory or their own personal notebook, then these updates will not be captured. Even if the AME consults the manual, the information may be lost if memory is trusted. It is preferable to print pages, or write pertinent information down, rather than to rely on memory of the information. In the aircraft maintenance environment, these situations represent chances for short-term memory failures: It is preferable to print pages, or write information down, rather than to rely on memory of the information 2023-01-12 B-09 Human Factors Page 86 of 340 CASA Part 66 - Training Materials Only  Claustrophobia and Physical Access Introduction Human phobias can be irrational and debilitating. But phobias usually arise from the body trying to protect itself. Fearing of falling from a height or of venomous snakes or spiders is quite rational; the mind wants to protect the body. Although not peculiar to aircraft maintenance engineering, working in restricted space and at heights is a feature of this trade. Problems associated with physical access are not uncommon. AMEs often have to access, and work in, very small spaces (e.g., in fuel tanks), cramped conditions (such as beneath ight instrument panels, inside lavatories), elevated locations (on cherry-pickers or high scaffolding), and uncomfortable climatic or environmental conditions (heat, cold, wind, rain, noise). This potential discomfort can be aggravated by aspects such as poor lighting, heat or cold, fumes or having to wear breathing apparatus. Claustrophobia Claustrophobia can be de ned as abnormal fear of being in an enclosed space. In many circumstances people may experience various levels of physical or psychological discomfort when in an enclosed or small space, which is generally considered to be quite normal. When this discomfort becomes extreme, it is known as claustrophobia. Claustrophobia 2023-01-12 B-09 Human Factors Page 87 of 340 CASA Part 66 - Training Materials Only  Con ned Space Access Fuel tank entry is a common con ned space task, but other parts of an aircraft are also de ned as con ned spaces, for example, behind the rear pressure bulkhead. Susceptibility to claustrophobia may become apparent only because of an incident when working within a con ned space, e.g., panic if unable to get out of a fuel tank. If an engineer suffers an attack of claustrophobia, they should make their colleagues and supervisors aware. If tasks in a con ned space cannot be avoided, maintenance crews should work as a team and assist one another if necessary, making allowances for the fact that people come in all shapes and sizes. © Sofema Aviation Services Fuel tank entry is a common con ned space task 2023-01-12 B-09 Human Factors Page 88 of 340 CASA Part 66 - Training Materials Only  Fear of Heights Working at signi cant heights can also be a problem. Some AMEs may be quite at ease in situations like these whereas others may be very uncomfortable. Whenever working at height, it is very important to make appropriate use of approved stands and scaffolding wherever possible. If the task requires AMEs to be more exposed to the risk of falling, they must properly use harnesses, safety ropes and other fall-arrest equipment. This equipment will not necessarily remove the fear of heights but will certainly help to reassure the AME and allow them to concentrate on the task at hand. Image by Victor Garcia from Unsplash If the task requires more exposure to the risk of falling proper use of harnesses, safety ropes and other fall-arrest equipment is required 2023-01-12 B-09 Human Factors Page 89 of 340 CASA Part 66 - Training Materials Only