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

This paper is concerned with which role the workload concept can play for the work organisation in a future remote control tower center. Nowadays you can find a control tower next to each airport equipped with a team of controllers maintain the declared surface movement rate under all weather conditions within the aerodrome visibility operational level (AVOL) while maintaining the required level of safety. New concepts for air traffic control (ATC) consider remote control for regional airports from a control center that includes working positions for the control of multiple airports. One important concept for the evaluation of controller working positions is workload. It is of interest to consider, what conclusions can be drawn from this concept for work design of a remote control center. In a simulator study at the Institute of Flight Guidance a remote center working environment was realized for controlling two regional airports. In a 3-factor experimental design it was investigated how workload ratings differed when (1) one controller was responsible for two airports; or when two controllers were responsible for two airports with (2) each controller responsible for one airport or rather (3) working in a team responsible for both airports. Workload ratings were gathered online using the ISA scale and after each simulation run using the NASA-TLX. In addition experts judged specific traffic situations in the single operator condition for two airports in respect to its operational feasibility. The data are discussed in respect to what can be learned from these data for work organisation and future ATC concepts. What are the sensitive data to guarantee for safe operations? A better understanding of the basic conditions a controller needs to meet his obligations as an air traffic controller are indispensible, when developing concepts for remote control of regional airports.

http://www.atmseminar.org/seminarContent/seminar9/papers/133-Moehlenbrink-Final-4-15-11.pdf

The Role of Workload for Work Organization in a Remote Tower Control Center

This study aims at explaining loss of separation events over the Swedish air space in 2011-2012, which occurred despite an automated conflict detection tool working as designed. The study suggests that there may be a trade-off between spending visual scan time on own conflict detection versus visual scan time spent on examining potential conflicts presented by the conflict detection automation. The issue is hard to solve, and is unfortunately far from resolved. This area of research requires a substantial applied research effort, if the goal is to both increase safety and capacity of ATM through the use of automation.

The use of conflict detection tools in air traffic management: an unobtrusive eye tracking field experiment during controller competence assurance

Remote control of airports implies application of cameras to replace direct visual observation from airport control towers by projection of the airport and its traffic in a remote control centre. Remote airport control is an emerging technique with benefits for smaller airports mainly, because it reduces the cost of personnel. Surprisingly, hardly any literature can be found to list the required visual objects and phenomena for tower control, i.e. the visual cues that need to be seen for tower control. The composition and validation of the so-called visual cue list for tower control is the subject of this paper. Tower controller task analysis was used to compose a ‘long-list’ of visual features. The long-list has been presented to a group of operational air traffic controllers to test the need and the circumstances to observe these visual cues. Our analysis shows that most of the visual cues are useful for operational tower control but are not strictly mandatory for applying the rules of the International Civil Aviation Organization.. The requirement for visual image resolution of remote tower control is the second subject of the paper. Our analysis leads to definition of a ‘short-list’ of important safety-related visual objects and phenomena for tower control and the conclusion that state of the art media are just able to provide the required image resolution for visual detection but not for recognition.

Assessment of visual cues by tower controllers, with implications for a Remote Tower Control Centre

New solutions in operational environments are often, among objective measurements, evaluated by using subjective assessment and judgement from experts. Anyhow, it has been demonstrated that subjective measures suffer from poor resolution due to a high intra and inter operator variability. Also, performance measures, if available, could provide just partial information, since an operator could achieve the same performance but experiencing a different workload. In this study we aimed to demonstrate i) the higher resolution of neurophysiological measures in comparison to subjective ones, and ii) how the simultaneous employment of neurophysiological measures and behavioural ones could allow a holistic assessment of operational tools. In this regard, we tested the effectiveness of an EEG-based neurophysiological index (WEEG index) in comparing two different solutions (i.e. Normal and Augmented) in terms of experienced workload. In this regard, 16 professional Air Traffic Controllers (ATCOs) have been asked to perform two operational scenarios. Galvanic Skin Response (GSR) has also been recorded to evaluate the level of arousal (i.e. operator involvement) during the two scenarios execution. NASA-TLX questionnaire has been used to evaluate the perceived workload, and an expert was asked to assess performance achieved by the ATCOs. Finally, reaction times on specific operational events relevant for the assessment of the two solutions, have also been collected. Results highlighted that the Augmented solution induced a local increase in subjects performance (Reaction times). At the same time, this solution induced an increase in the workload experienced by the participants (WEEG). Anyhow, this increase is still acceptable, since it did not negatively impact the performance and has to be intended only as a consequence of the higher engagement of the ATCOs. This behavioural effect is totally in line with physiological results obtained in terms of arousal (GSR), that increased during the scenario with augmentation. Subjective measures (NASA-TLX) did not highlight any significant variation in perceived workload. These results suggest that neurophysiological measure provide additional information than behavioural and subjective ones, even at a level of few seconds, and its employment during the pre-operational activities (e.g. design process) could allow a more holistic and accurate evaluation of new solutions.

/pdf/how-neurophysiological-measures-can-be-used-to-enhance-the-3wbnj9aqbv.pdf

How neurophysiological measures can be used to enhance the evaluation of remote tower solutions

Remote control of airports implies application of cameras to replace direct visual observation from airport control towers by projection of the airport and its traffic in a remote control centre. Surprisingly, hardly any literature can be found to list the required visual objects and phenomena for tower control, i.e. the visual cues that need to be seen for tower control. The composition and validation of the so-called visual cue list for tower control is the subject of this study. Tower controller task analysis was used to compose a ‘long-list’ of visual features. The long-list has been presented to a group of operational air traffic controllers to test the need and the circumstances to observe these visual cues. Our analysis shows that most of the visual cues are useful for operational tower control but are not strictly mandatory for applying the rules of the International Civil Aviation Organisation. The requirement for visual image resolution of remote tower control is the second subject of the paper. Our analysis leads to definition of a ‘shortlist’ of important safety-related visual objects and phenomena for tower control and the conclusion that state-of-the-art media are just able to provide the required image resolution for visual detection but not for recognition.

Detection and Recognition for Remote Tower Operations

The Advanced Remote Tower project (ART) studies enhancements to an existing LFV prototype facility for a remotely operated tower: projection on a 360 degrees panorama screen, adding synthesized geographic information and meteorological information, video tracking, fusion of video and radar tracks, labelling, visibility enhancement and surveillance operations with a remotely controlled Pan Tilt Zoom camera. The ART functions have been embedded in the existing Swedish test facility for remote tower operations in Malmo airport Sturup observing Angelholm traffic about 100 km to the North. They were tuned and validated by 15 tower controllers. Emphasis was on the traffic and situation awareness of tower controllers using remote cameras and projection system for safe operational tower control, replacing direct view on the airport and its traffic. The validation results give valuable information for further development and operational application even outside the Remote Tower application area.

Advanced remote tower project validation results

The Advanced Remote Tower (ART) project studied enhancements to an existing LFV prototype facility (ROT) for a single airport remotely operated tower: projection on a 360° panorama screen, adding synthesised geographic information and meteorological information, video tracking, fusion of video and radar tracks, labelling, visibility enhancement and surveillance operations with a remotely controlled Pan Tilt Zoom camera. The ART functions have been embedded in the existing Swedish test facility for single airport remote tower operations in Malmo airport Sturup observing Angelholm traffic about 100 km to the North. These functions were tuned and validated during tests with 15 operational tower air traffic controllers. Emphasis was on the traffic and situation awareness of the tower controllers using remote cameras and a projection system for safe operational tower control, replacing direct view on the airport and its traffic. The validation results give valuable information for further development and operational application even outside the Remote Tower application area.

J.J.M. Roessingh

Papers

Assessment of visual cues by tower controllers, with implications for a Remote Tower Control Centre

Detection and Recognition for Remote Tower Operations

Advanced remote tower project validation results

The Advanced Remote Tower System and Its Validation

Advanced Remote Tower project