The development and deployment of a maintenance operations safety survey

Objective: Based on the line operations safety audit (LOSA), two studies were conducted to develop and deploy an equivalent tool for aircraft maintenance: the maintenance operations safety survey (MOSS). Background: Safety in aircraft maintenance is currently measured reactively, based on the number of audit findings, reportable events, incidents, or accidents. Proactive safety tools designed for monitoring routine operations, such as flight data monitoring and LOSA, have been developed predominantly for flight operations. Method: In Study 1, development of MOSS, 12 test peer-to-peer observations were collected to investigate the practicalities of this approach. In Study 2, deployment of MOSS, seven expert observers collected 56 peer-to-peer observations of line maintenance checks at four stations. Narrative data were coded and analyzed according to the threat and error management (TEM) framework. Results: In Study 1, a line check was identified as a suitable unit of observation. Communication and third-party data management were the key factors in gaining maintainer trust. Study 2 identified that on average, maintainers experienced 7.8 threats (operational complexities) and committed 2.5 errors per observation. The majority of threats and errors were inconsequential. Links between specific threats and errors leading to 36 undesired states were established. Conclusion: This research demonstrates that observations of routine maintenance operations are feasible. TEM-based results highlight successful management strategies that maintainers employ on a day-to-day basis. Application: MOSS is a novel approach for safety data collection and analysis. It helps practitioners understand the nature of maintenance errors, promote an informed culture, and support safety management systems in the maintenance domain

The development of the maintenance operations safety survey: challenges in transferring a predictive safety tool from flight operations to aircraft maintenance

Predicting human behaviour and managing human error is arguably the greatest challenge facing the aviation industry today (Shappell and Wiegmann, 2009). In order to gain a better understanding of human behaviour and overall organizational safety performance, the industry is moving towards monitoring of normal operations (Helmreich et al., 2003). One of the key advantages is the learning opportunity without the negative consequences and associated costs of an incident or accident. Predictive tools such as the Line Operations Safety Audit (LOSA) provide objective information of routine operational performance, complement existing safety data collection programs and are endorsed by the International Civil Aviation Organization (ICAO)

Pilots’ visual scan pattern and situation awareness in flight operations

Introduction: Situation awareness (SA) is considered an essential prerequisite for safe flying. If the impact of visual scanning patterns on a pilot’s situation awareness could be identified in flight operations, then eye-tracking tools could be integrated with flight simulators to improve training efficiency. Method: Participating in this research were 18 qualified, mission-ready fighter pilots. The equipment included high-fidelity and fixed-base type flight simulators and mobile head-mounted eye-tracking devices to record a subject’s eye movements and SA while performing air-to-surface tasks. Results: There were significant differences in pilots’ percentage of fixation in three operating phases: preparation (M = 46.09, SD = 14.79), aiming (M = 24.24, SD = 11.03), and release and break-away (M = 33.98, SD = 14.46). Also, there were significant differences in pilots’ pupil sizes, which were largest in the aiming phase (M = 27,621, SD = 6390.8), followed by release and break-away (M = 27,173, SD = 5830.46), then preparation (M = 25,710, SD = 6078.79), which was the smallest. Furthermore, pilots with better SA performance showed lower perceived workload (M = 30.60, SD = 17.86), and pilots with poor SA performance showed higher perceived workload (M = 60.77, SD = 12.72). Pilots’ percentage of fixation and average fixation duration among five different areas of interest showed significant differences as well. Discussion: Eye-tracking devices can aid in capturing pilots’ visual scan patterns and SA performance, unlike traditional flight simulators. Therefore, integrating eye-tracking devices into the simulator may be a useful method for promoting SA training in flight operations, and can provide in-depth understanding of the mechanism of visual scan patterns and information processing to improve training effectiveness in aviation

Pilots’ visual scan pattern and attention distribution during the pursuit of a dynamic target

Introduction: The current research is investigating pilots’ visual scan patterns in order to assess attention distribution during air-to-air manoeuvers. Method: A total of thirty qualified mission-ready fighter pilots participated in this research. Eye movement data were collected by a portable head-mounted eye-tracking device, combined with a jet fighter simulator. To complete the task, pilots have to search for, pursue, and lock-on a moving target whilst performing air-to-air tasks. Results: There were significant differences in pilots’ saccade duration (msec) in three operating phases including searching (M=241, SD=332), pursuing (M=311, SD=392), and lock-on (M=191, SD=226). Also, there were significant differences in pilots’ pupil sizes (pixel2) of which lock-on phase was the largest (M=27237, SD=6457), followed by pursuing (M=26232, SD=6070), then searching (M=25858, SD=6137). Furthermore, there were significant differences between expert and novice pilots on the percentage of fixation on the HUD, time spent looking outside the cockpit, and the performance of situational awareness (SA). Discussion: Experienced pilots have better SA performance and paid more attention to the HUD but focused less outside the cockpit when compared with novice pilots. Furthermore, pilots with better SA performance exhibited a smaller pupil size during the operational phase of lock-on whilst pursuing a dynamic target. Understanding pilots’ visual scan patterns and attention distribution are beneficial to the design of interface displays in the cockpit and in developing human factors training syllabi to improve safety of flight operations

The impact of alerting designs on air traffic controller's eye movement patterns and situation awareness

This research investigated controller’ situation awareness by comparing COOPANS’s acoustic alerts with newly designed semantic alerts. The results demonstrate that ATCOs’ visual scan patterns had significant differences between acoustic and semantic designs. ATCOs established different eye movement patterns on fixations number, fixation duration and saccade velocity. Effective decision support systems require human-centred design with effective stimuli to direct ATCO’s attention to critical events. It is necessary to provide ATCOs with specific alerting information to reflect the nature of of the critical situation in order to minimize the side-effects of startle and inattentional deafness. Consequently, the design of a semantic alert can significantly reduce ATCOs’ response time, therefore providing valuable extra time in a time-limited situation to formulate and execute resolution strategies in critical air safety events. The findings of this research indicate that the context-specified design of semantic alerts could improve ATCO’s situational awareness and significantly reduce response time in the event of Short Term Conflict Alert activation which alerts to two aircraft having less than the required lateral or vertical separation

How much is too much on monitoring tasks? Visual scan patterns of single air traffic controller performing multiple remote tower operations

The innovative concept of multiple remote tower operation (MRTO) is where a single air traffic controller (ATCO) provides air traffic services to two or more different airports from a geographically separated virtual Tower. Effective visual scanning by the air traffic controller is the main safety concern for human-computer interaction, as the aim of MRTO is a single controller performing air traffic management tasks originally carried out by up to four ATCOs, comprehensively supported by innovative technology. Thirty-two scenarios were recorded and analyzed using an eye tracking device to investigate the above safety concern and the effectiveness of multiple remote tower operations. The results demonstrated that ATCOs' visual scan patterns showed significant task related variation while performing different tasks and interacting with various interfaces on the controller's working position (CWP). ATCOs were supported by new display systems equipped with pan tilt zoom (PTZ) cameras allowing enhanced visual checking of airport surfaces and aircraft positions. Therefore, one ATCO could monitor and provide services for two airports simultaneously. The factors influencing visual attention include how the information is presented, the complexity of that information, and the characteristics of the operating environment. ATCO's attention distribution among display systems is the key human-computer interaction issue in single ATCO performing multiple monitoring tasks

Pilot’s attention distributions between chasing a moving target and a stationary target

Introduction: Attention plays a central role in cognitive processing; ineffective attention may induce accidents in flight operations. The objective of current research was to examine military pilots’ attention distributions between chasing a moving target and a stationary target. Method: Thirty-seven mission-ready F-16 pilots participated in the current research. Subjects’ eye movements were collected by a portable head-mounted eye-tracker during tactical training in a flight simulator. The scenarios of chasing a moving target (air-to-air) and a stationary target (air-to-surface) consist of three operational phases; searching, aiming and lock-on to the targets. Results: The findings demonstrated significant differences in pilots’ percentage of fixation during searching phase between air-to-air (M=37.57, SD=5.72) and air-to-surface (M=33.54, SD=4.68). Fixation duration can indicate pilots’ sustained attention to the trajectory of a dynamic target during dog-fight manoeuvers. Aiming for the stationary target with larger pupil size (M=27105 pixel2, SD=6565 pixel2) reflects higher cognitive loading than aiming to the dynamic target (M=23864 pixel2, SD=8762 pixel2). Discussion: Pilots’ visual behavior is not only closely related to attention distribution, but also significantly associated with task characteristics. Military pilots demonstrated various visual scan patterns for searching and aiming to different types of targets based on the research settings of flight simulator. The findings would facilitate system designers’ understandings of military pilots’ cognitive processes during tactical operations. It will assist human-centered interface design to improve pilots’ situational awareness. The application of an eye-tracking device integrated with a flight simulator is a feasible and cost-effective intervention to improve efficiency and safety of tactical training

The development of eye tracking in aviation (ETA) technique to investigate pilot's cognitive processes of attention and decision-making

Eye tracking device had provided researchers a promising way to investigate what pilot‘s cognitive processes when they see information present on the flight deck. There are 35 participants consisted by pilots and avionics engineers participated in current research. The research apparatus include an eye tracker and a flight simulator divided by five AOIs for data collection. The research aims are to develop cost-efficiency of eye tracking technique in order to facilitate scientific research of cognition and decision-making in aviation. The results indicated that participants’ eye movement patterns did have significant differences on the following variables including fixation count, F(4, 136) = 601.01, p < .001; average fixation duration, F(4, 136) = 100.87, p < .001; percentage of total fixations, F(4, 136) = 779.92, p < .001, and average pupil area, F(4, 136)=2.51, p < .05. The findings demonstrated that eye tracker is a suitable tool to investigate pilots’ cognitive process of attention and decision-making on flight deck. Furthermore, it can be applied to improve pilots’ SA and decision-making during flight operations

The economics of safety : a case study of the UK offshore helicopter industry

The International Civil Aviation Organisation maintains that future viability of air transportation may well be predicated on perception of safety rather than any more tangible measures. In order to keep safety risks at an acceptable level it advocates a change of fundamental approach to the system of safety management, one that is more proactive. This study examines the causes of such a requirement for change, and the scope for improving the efficiency of what Calabresi refers to as the second principal goal of accident law, namely accident cost reduction. First, testing the validity of the traditional approach to safety analysis and management, as stated in regulatory guidelines. Secondly, examining the possibility that the efficiency of safety cost-benefit analysis can be practicably improved. A subsequent aim is to find an empirically based proxy measure for the acceptability of risk by examining the outcomes to potential safety related risk scenarios. Such a measure, if validated, may convert many existing intangible assessments concerning safety management into more transparent and reliable judgements. The offshore helicopter industry has many unique characteristics, some of which derive from the fact that the customers, the oil & gas companies, are more powerful than the operators. Others relate to the absence of any intermodal competition, and passengers who are specially trained to be properly aware of their safety. As choice is severely limited, this population is also likely to reflect a much broader range of risk preference. A carefully structured questionnaire was presented to a sample of these passengers, and the responses analysed in depth. The conclusions of this study are that choice is driven by the perceptions of safety, and that market stability is only maintained with the pre-condition that safety is deemed acceptable. Further, the failure of this pre-condition will follow a predictable pattern, based on a normal distribution for the population. The recommendation of this study is that such reactions to perceptions of safety risk are given due consideration alongside traditional costbenefit analysis, and in so doing it is likely that more secondary and tertiary accident cost factors will be more fully addressed. This will improve the overall efficiency of accident costs reduction, and make a significant contribution to the aim of proactive safety management.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Hazards awareness for aircraft accident investigators

Hazards on accident sites are such that investigators must balance personal safety against the risks involved in collecting evidence intended to prevent future loss of life. Better knowledge of hazards and their mitigation could reconcile these conflicting objectives to a point at which risk might be no greater than in other workplaces. Nevertheless, the magnitude and nature of the hazards at any accident site cannot be determined in advance. The perceptions of novice accident investigators of potential hazards are not greatly different from the realities encountered by experienced investigators, although the former tend to focus on general health and safety issues, while experienced investigators are more aware of hazards arising from aircraft systems and materials. Experienced investigators reported most of the hazards they encountered over six years as arising within a narrow range of hazard categories - yet they must be prepared to carry out thorough investigations while protecting themselves against all hazards, including those encountered very infrequently. Both generic and dynamic risk assessments are important in protecting investigators and the integrity of evidence. The ongoing management of an investigation in the field involves a continuous and iterative cycle: identification of hazards, determination of exposure, assessment of risk, introduction of controls, review and assessment of remaining risk, and identification and management of residual hazard. Lives and evidence depend upon the quality of this process. At present, great reliance is placed on personal protection equipment as a control on hazards. Observation of participants in training programmes has identified instances of poor selection and ineffective use of such equipment to the extent that it has provided no protection. The thesis points to required further directions in the training of investigators - an investment which will yield its dividend in the prevention of future accidents and loss of life.EThOS - Electronic Theses Online ServiceGBUnited Kingdo