Academic literature on the topic 'Air traffic controller workload'

The current Air Traffic Management (ATM) system, based on principles established more than 50 years ago, is starting to show clear signs of saturation. This fact. joined to increasingly environmental awareness, leads to a paradigm shift from the current sector-based ATM system, to a future trajectory-based ATM system. Within this research, factors and processes affecting trajectory-based operations are analysed, and the main factors hindering an accurate trajectory definition identified, in order to establish the criteria under which two aircraft trajectories could be declared as compatible in a pre-tactical management stage. Trajectory compatibility determination will endeavour to reduce the real-time Air Traffic Controller‟s (ATCO‟s) workload in the tactical stage, currently identified as one of the main bottlenecks in the existing ATM system. The obtained results are based on a trade-off between the system capacity, understood as the number of ATCO tactical interventions, versus the system predictability, as the number of misdetections or probability of conflict to be assumed in a pre-tactical timeframe. A criterion to identify when two trajectories are compatible is presented, firstly considering the movement as horizontal only, then including the vertical components when one or both aircraft are climbing or descending. The research initial results were presented in a Paper in the first SESAR Innovation Days which took place at Toulouse from the 29th of November 2011 to the 1st of December 2011 (Paper included as Annex V).

The thesis describes an investigation into Air Traffic Control (ATC) complexity as a contributory factor in changes of controllers' workload. It is considered that ATC complexity, together with equipment interface and procedural demands comprise the task demands imposed on the en-route controller to perform certain activities, which mediated by performance shaping factors create workload. The data used to study this relationship came from ATC real-time simulations completed at EUROCONTROL CRDS in Budapest: recorded flown trajectories, communication performed by the controller (whether with other controllers or with the pilots), data entries related to flight data management, and instantaneous self-assessment ratings of workload provided by the controllers were used. The ATC complexity factors that have been consistently found to be important in the previous studies (related to aircraft density, flight attributes of each individual aircraft, aircraft conflicts and traffic disorder) and for which detailed calculation formula have been reported were selected for further analysis. Since the established set of factors resulted from multiple researches conducted in this field, it was assumed that some of these factors are correlated with one another, overlapping and possibly measuring similar concepts. Therefore, a reduction of the initial set of factors was performed by combining information contained within these factors into a smaller number of new artificial variables and by deleting statistically redundant portions of these factors prior to conducting further analysis. The Principal Component Analysis (PCA), which is the statistical method applied to achieve required reduction, resulted in the overall set of 6 complexity components, whose interpretations are driven by the factors that showed the strongest correlation with that component. In order to establish a link between ATC complexity and a controller's subjective workload, multiple regression analysis was performed, using the complexity components identified in the PCA as predictors of the workload ratings. In addition, some measures of controller’s activity (data entries made by the controllers related to flight data management, cumulative duration of radio calls, i.e. frequency occupancy time, and average duration of single calls) were added to the analysis to test whether information about the controller’s activity could be also useful for predicting workload, once the effect of complexity had been considered, and to verify whether the effect of complexity on workload could be mediated by the effect of complexity on the controller’s activity. The analysis revealed that both ATC complexity and the activities that the controller performs to deal with a demand imposed on him/her give a unique contribution to the prediction of workload ratings and therefore the workload of the controller is determined by both ATC complexity and controller’s activities. In addition, it was assumed that the workload is differently impacted by individual components of complexity, and further statistical analyses were performed to test this assumption. Understanding these differences could in fact facilitate comparison of the complexity levels of a single sector under different conditions, but also comparison of complexity levels of different sectors under same conditions. Firstly the changes in the workload and activities of the controllers under different conditions were investigated using analysis of variance. Subsequently, in order to be able to map these changes on the complexity components, it was necessary also to investigate into the changes that the complexity components undergo when observed under different conditions. The results revealed different behaviour of single complexity components when mapped on the changes recorded in the activities of the controller and workload, demonstrating that changes in controller’s activities and perceived workload are driven by different complexity components in different sectors and under different operational conditions. Shedding light on these contributors to the workload experienced by a controller can greatly facilitate the introduction of any change envisaged for the airspace under consideration. Namely, in the current structure, whenever new procedures or new working methods are subject to possible deployment, the identified complexity components could support the estimation of the impact that those changes would impose on the workload of the controller and further on decision making processes. Additionally, the complexity components are also applicable in the validation of the new concepts and new technologies to be introduced in the system when designing simulation scenarios against which new concepts would be assessed. As also demonstrated by the analysis, the comparison of different sectors, or even different sector designs within the same airspace, could be compared and contribute to the improvement of airspace design<br>Die vorliegende Arbeit untersucht die Komplexität der Flugverkehrskontrolle (Air Traffic Control, ATC) als einen wesentlichen Einflussfaktor auf die Arbeitsbelastung des Radarlotsen. Die zentrale Annahme ist dabei, dass die Komplexität der ATC zusammen mit den Anforderungen aus den betrieblichen Rahmenbedingungen (technische Systemschnittstellen und Prozeduren) den Lotsen zu bestimmten Abläufen zwingen, welche die Arbeitsbelastung signifikant beeinflussen. Für die durchgeführten Untersuchungen standen Daten von ATC-Echtzeitsimulationen von EUROCONTROL CRDS Budapest zur Verfügung, die folgende Informationen umfassen: abgeflogene Flugtrajektorien, Kommunikationsprotokolle der Lotsen (untereinander oder zwischen Lotse und Pilot), Daten aus dem flight-data Management und Daten aus der regelmäßigen Selbstbewertung der Lotsen bezüglich ihrer aktuell gefühlten Arbeitsbelastung. Die bereits in früheren Studien identifizierten Komplexitätsvariablen (insbesondere die lokale Flugzeugdichte, spezifische Flugzeugeigenschaften, Konfliktsituationen zwischen Flugzeugen und die Verkehrslage betreffend) sowie hierzu erarbeitete mathematische Vorschriften bilden die Grundlage für die weiterführenden, detaillierten Untersuchungen. Aufgrund der Vielzahl an Komplexitätsvariablen aus diversen wissenschaftlichen Quellen war davon auszugehen, dass Korrelationen unter den Variablen vorliegen. Aus diesem Grund wurden zunächst statistisch redundante Informationen der ursprünglich vorliegenden Variablen reduziert, sodass als Ergebnis neue voneinander unabhängige Faktoren klassifiziert werden konnten. Die hierfür verwendete Hauptkomponentenanalyse (Principal Component Analysis - PCA) führte zu sechs statistisch signifikanten Komplexitätsfaktoren, die anhand der höchsten Korrelation zur zugeordneten Komponente interpretiert wurden. Um die Verbindung zwischen der ATC Komplexität und der subjektiv empfundenen Arbeitsbelastung herzustellen, wurde eine multiple Regressionsanalyse zwischen den Komplexitätsfaktoren und den abgeleiteten Arbeitsbelastungszuständen durchgeführt. Zusätzlich lagen für die Analyse der Arbeitsbelastung auch Daten über die Arbeitsaufgaben des Lotsen vor (bspw. Dateneinträge des Lotsen, Gesamtlänge der Funkanweisungen, durchschnittliche Länge der Funkanweisungen), um zu untersuchen, inwieweit sich aus den aktuell durchgeführten Arbeitsaufgaben bei gegebener Verkehrsnachfrage eine verlässliche Vorhersage über die Arbeitsbelastung ableiten lässt. Die Analyse zur Vorhersage der Arbeitsbelastung konnte zeigen, dass sowohl die ATC Komplexität als auch die aktuellen Arbeitsaufgaben einen individuellen und signifikanten Einfluss haben. Weiterhin wurde unterstellt, dass die spezifischen Komplexitätsfaktoren einen unterschiedlichen Effekt auf die Arbeitsbelastung ausüben. Die Überprüfung dieser Annahme war ebenfalls Bestandteil der umfangreichen statistischen Untersuchungen. Tatsächlich könnte ein fundamentales Verständnis der Komplexitätsgrade den Vergleich einzelner Luftraumsektoren unter verschiedenen operativen Randbedingungen, als auch den Vergleich unterschiedlicher Luftraumsektoren mit vergleichbaren operativen Randbedingungen wesentlich erleichtern. Zuerst wurden die Veränderungen der Arbeitsbelastung und -die Tätigkeiten der Lotsen unter Verwendung einer Varianzanalyse untersucht. Um eine valide Zuordnung zu den Komplexitätsfaktoren sicherzustellen, war es ebenfalls notwendig, die Veränderungen dieser Faktoren und Tätigkeiten unter wechselnden Randbedingungen zu analysieren. Die Analysen zeigen hierbei unterschiedliche Resultate bezüglich der jeweiligen Komplexitätsfaktoren. So beeinflussen die verschiedenen Komplexitätsfaktoren die Handlungsabläufe der Lotsen und die wahrgenommene Arbeitsbelastung, jedoch in Abhängigkeit von den ausgewählten Sektoren und den betrieblichen Randbedingungen. Unter Berücksichtigung dieser erarbeiteten Abhängigkeiten der Arbeitsbelastung des Lotsen können nun die Auswirkungen von Veränderungen im Luftraum zuverlässig bestimmt werden. Gerade in Bezug auf Veränderungen der gegenwärtigen Luftraumstruktur oder die Einführung neuer Prozeduren oder Arbeitsabläufe können die entwickelten Komplexitätsfaktoren bereits frühzeitig Aufschluss darüber geben, welche Konsequenzen solche Veränderungen auf die Arbeitsbelastung der Lotsen nach sich ziehen können und Entscheidungsprozesse unterstützen. Weiterhin sind die entwickelten Komplexitätsfaktoren als Grundlage für die Validierung neuer Konzepte und Technologien, gegebenenfalls unter Verwendung von entwickelten Simulationsszenarien, nutzbar. Darüber hinaus können die Komplexitätsfaktoren für die Gegenüberstellung von verschiedenen Luftraumsektoren genutzt werden und zur Abwägung bzw. Optimierung von Entwürfen eines Luftraumdesigns dienen

From 2010 to 2030, the number of instrument flight rules aircraft operations handled by Federal Aviation Administration en route traffic centers is predicted to increase from approximately 39 million flights to 64 million flights. The projected growth in air transportation demand is likely to result in traffic levels that exceed the abilities of the unaided air traffic controller in managing, separating, and providing services to aircraft. Consequently, the Federal Aviation Administration, and other air navigation service providers around the world, are making several efforts to improve the capacity and throughput of existing airspaces. Ultimately, the stated goal of the Federal Aviation Administration is to triple the available capacity of the National Airspace System by 2025. In an effort to satisfy air traffic demand through the increase of airspace capacity, air navigation service providers are considering the inclusion of advisory conflict-detection and resolution systems. In a human-in-the-loop framework, advisory conflict-detection and resolution decision-support tools identify potential conflicts and propose resolution commands for the air traffic controller to verify and issue to aircraft. A number of researchers and air navigation service providers hypothesize that the inclusion of combined conflict-detection and resolution tools into air traffic control systems will reduce or transform controller workload and enable the required increases in airspace capacity. In an effort to understand the potential workload implications of introducing advisory conflict-detection and resolution tools, this thesis provides a detailed study of the conflict event process and the implementation of conflict-detection and resolution algorithms. Specifically, the research presented here examines a metric of controller taskload: how many resolution commands an air traffic controller issues under the guidance of a conflict-detection and resolution decision-support tool. The goal of the research is to understand how the formulation, capabilities, and implementation of conflict-detection and resolution tools affect the controller taskload (system demands) associated with the conflict-resolution process, and implicitly the controller workload (physical and psychological demands). Furthermore this thesis seeks to establish best practices for the design of future conflict-detection and resolution systems. To generalize conclusions on the conflict-resolution taskload and best design practices of conflict-detection and resolution systems, this thesis focuses on abstracting and parameterizing the behaviors and capabilities of the advisory tools. Ideally, this abstraction of advisory decision-support tools serves as an alternative to exhaustively designing tools, implementing them in high-fidelity simulations, and analyzing their conflict-resolution taskload. Such an approach of simulating specific conflict-detection and resolution systems limits the type of conclusions that can be drawn concerning the design of more generic algorithms. In the process of understanding conflict-detection and resolution systems, evidence in the thesis reveals that the most effective approach to reducing conflict-resolution taskload is to improve conflict-detection systems. Furthermore, studies in the this thesis indicate that there is significant flexibility in the design of conflict-resolution algorithms.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2012.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 79-81).<br>New capabilities of Air Traffic Control (ATC) under development in Next Generation Air Transportation system (NextGen) will increase the system capacity to accommodate the expected growth in the air traffic. One of the key enablers of the NextGen capabilities is advanced onboard equipage of the aircraft. During the transition to NextGen, aircraft with different equipage levels will coexist in the same airspace: mixed-equipage. To reduce the mixed-equipage period, the Federal Aviation Administration (FAA) proposed "best-equipped, best-served policy" as a governing principle for accelerating NextGen equipage, offering incentives to the early adopters of NextGen avionics. However, the policy may introduce new tasks to the air traffic controllers, increasing the cognitive workload and decreasing the controller performance. The policy may be implemented at the strategic or the tactical level. This thesis identified two representative tactical level policies that may increase the difficulty and workload of the en-route air traffic controllers: best-equipped, first-served (BEFS) policy and best-equipped, exclusively served (BEES) policy. To investigate the impact of the potential tactical best-equipped, best-served policies on en-route controller performance and workload, a human-in-the-loop simulation was developed to compare the impacts of the two identified potential policies and the current first-come, first-served policy. The two potential tactical best-equipped, best-served policies provided marginal operational incentives to the NextGen equipage aircraft; however, the policies significantly increased the controller errors and reduced the total system efficiency with considerable delays to the less equipped aircraft compared to the current policy. In addition, higher subjective workload rating with the potential policies, especially during heavy traffic loads, indicated an increase in the controller workload and a reduction of the controller capacity. The analysis suggests that caution needs to be exercised when considering implementation of best-equipped best-served policy at the tactical level. Therefore, a strategic level implantation of the best-equipped, best-served policy is recommended; however, this study did not address impact of the strategic level implementation of the policy.<br>by HongSeok Cho.<br>S.M.

This study was conducted at the Swedish Defense research agency as an attempt to understand affordances and limitations in visualizing altitude information for fighter controllers. The fighter controllers are subject to large quantities of numerical information from multiple sources simultaneously. Their duties are highly stressful and require large mental workload and situational awareness. Today, a large portion of information is represented visually, except for altitude. The altitude of a jet is represented only numerically on the screen, next to the icon representing an airplane. This thesis attempts to aid the users in their tasks, by determining if interactive visual information could benefit the current system. This study resulted in one prototype, where height was represented in three different ways, one using color coordination, one using different sizes and one mimicked the current numerical representation. These variations were evaluated in a user study, consisting of semi structured interviews along with benchmark tests. None of the suggested visual cues could be demonstrated as more efficient than the current representation, but a majority of participants preferred the version using varying sizes as this was considered more intuitive and held less limitations than the other version. Future research is encouraged as to successfully determine if altitude information can be visually represented for a decreased mental workload.<br>Denna studie genomfördes vid Totalförsvarets Forskningsinstitut som ett försök att utreda möjligheter och svårigheter med att visuellt presentera information om altitud för flygstridsledare. Flygstridsledare utsätts för stora mängder numerisk information, från ett flertal olika källor simultant. Derad uppgifter utförs under hög stress och kräver stor mental belastning samt situationsmedvetenhet. Idag representeras en stor mängd information visuellt, på flygstridsledarens radarskärm, med undantaget för höjden. Ett objekts altitud på skärmen representeras alltid numeriskt, bredvid ikonen för flygplan. Detta arbete har gjorts i avsikt att hjälpa flygstridsledaren i dennes uppgifter, genom att utreda om interaktiv visuell information kan vara av nytta för deras nuvarande system. Denna studie resulterade i en prototyp, i vilken höjd representerades på tre olika sätt. Genom färg med varierande opacitet, genom olika storlekar på objekten, samt den nuvarande numeriska metoden. Dessa versioner utvärderades i en användarstudie, bestående av semistrukturerade intervjuer samt benchmark test. Ingen av de föreslagna visualiseringarna kunde påvisas mer effektiv än det nuvarande systemet, men en majoritet av deltagarna föredrog versionen med varierande storlekar, eftersom detta ansågs mer intuitivt samt hade färre begränsningar. Vidare studier uppmanas för att med framgång avgöra om altituden kan representeras visuellt, för en minskad mental belastning.

A crescente demanda por transporte aéreo tem provocado um aumento na densidade do fluxo de aeronaves no espaço aéreo. A sobrecarga cada vez maior de aeronaves nos setores estáticos do espaço aéreo, cujos controles são de responsabilidade dos controladores de tráfego aéreo, provoca um estado de alerta constante no gerenciamento do tráfego aéreo. Uma única falha na monitoração e controle dos setores, realizadas pelos controladores de tráfego aéreo, pode por em risco a vida de centenas de pessoas. Para garantir a segurança do espaço aéreo, o controlador de tráfego aéreo tem que realizar várias tarefas no seu dia-a-dia, estando exposto a uma carga de trabalho. Uma das frentes de pesquisas que busca balancear a carga de trabalho dos controladores de tráfego aéreo é a Re-setorização Dinâmica. O objetivo deste trabalho de pesquisa é investigar como se comporta a carga de trabalho dos controladores de tráfego aéreo com a utilização da Re-setorização Dinâmica, tendo como estudo de caso um espaço aéreo brasileiro de alta densidade de aeronaves.<br>The growing demand for air transportation has caused an increase in the density of aircraft flow in the airspace. The overload of aircraft in airspace sectors, which are under the air traffic controllers\' responsibility, causes a permanent alert state in the air traffic management. A single controller\'s fault with monitoring and controlling a sector may endanger hundreds of people\'s lives. The air traffic controller has to perform many activities daily in order to assure safety to the air space, being exposed to a certain workload. The Dynamic Resectorization is a research line in this direction that aims to balance the workload of the air traffic controllers. The goal of this research work is to investigate the behavior of the air traffic controller workload through the use of Dynamic Resectorization, having as a case study a Brazilian air space with high aircraft density.