Air Traffic Control Tower Research Articles

Synthesis of Remote Air Traffic Control System and Air Traffic Controllers’ Perceptions

Airports face financial constraints in the use of services of air traffic control (ATC) towers. The remote air traffic control system (RATCS) is anticipated to be an economical and safe alternative to a control tower. RATCS is a concept intended to supply ATC to an airport by providing communication, navigation, and surveillance from a remote location. This study aims to gain insights about RATCS by conducting a review of existing studies, airport visits, discussions with RATCS technology providers, RATCS demonstration visits, and questionnaire surveys and interviews of controllers. A major inference from nontowered airport visits is that the introduction of RATCS will present many challenges such as pilot readiness to be supervised by RATCS, differences in local conditions, and significant limitations in available infrastructure. The knowledge gained through airport–demonstration visits and meetings with RATCS providers assisted in designing a questionnaire survey and interview. The number of surveys and interviews was limited; hence, conducting a comprehensive quantitative evaluation from responses was difficult. Nevertheless, controllers who participated in the study developed a consensus. The survey outcomes showed that controllers had concerns about RATCS functionality for communication or coordination between controllers and for ATC in high traffic conditions. The controllers provided favorable responses toward new features of RATCS, such as infrared cameras, high-definition monitors, target tracking functionality, and runway overlays. Potential advantages of RATCS anticipated by some controllers include systems with replay capabilities, situational awareness capabilities in low-visibility conditions, and surveillance capabilities of ground operations.

Modeling current and emerging threats in the airport domain through adversarial risk analysis

Airports are critical infrastructures entailing intense human, commercial and economic activity. As such, they are preferred targets for criminal and terrorist groups, who are attracted by the promisingly high revenues they might get from an attack. Every year, airport authorities worldwide have to face, with limited resources, attacks arising from different adversaries. There are several sensible areas within an airport organization that are especially vulnerable to the terrorist threat, including, among others: (1) those related to human lives (of passengers or staff); (2) airport infrastructure (airport perimeter, main terminal, Air Traffic Control Tower, runways, hangars, etc.); (3) aircrafts and other ground vehicles; and (4) IT systems and services. Besides the more traditional ones, we are particularly concerned with attacks launched against the last type of targets, an emerging and increasingly worrisome threat. Specifically, we analyze the impact of cyber-attacks launched by organized groups whose main goal is to take hold of airport operations. In some cases, in order to have more chances to achieve their purpose (and take advantage of its eventual success), cyber attackers may be backed up by a terrorist group who will try to interfere with the Air Traffic Management network. In this paper, we aim at supporting airport authorities in their fight against both threats, by devising a security allocation plan. We provide an adversarial risk analysis model to address the problem, and apply it to obtain the optimal portfolio of preventive measures in an illustrative case study. The model is open to extensions, as e.g. larger and more complex technical infrastructures, new threats, or additional recovery measures deployed by different defensive agents.

Agency policy preferences, congressional letter-marking and the allocation of distributive policy benefits

AbstractWhen allocating distributive benefits, bureaucrats must balance their own policy preferences with requests from members of Congress. The elimination of earmarking may provide agency personnel with greater discretion in the allocation of distributive benefits. Using a novel data set of congressional letters written in support of their community’s air traffic control towers, we estimate a model that explores the Federal Aviation Administration’s decision to issue national interest exemptions to continue operations at towers slated for closure as a result of budget sequestration. Our analysis suggests that members of Congress do not enjoy the influence they possessed under earmarking when using a new method, letter-marking, to influence how agencies distribute benefits.

Economic Impact of a Lightning Strike–Induced Outage of Air Traffic Control Tower

This research investigates how lightning strike–induced outages of airport infrastructure and facilities affect airport performance from an economic perspective, using Baltimore (Maryland)–Washington (D.C.) Thurgood Marshall International (BWI) Airport as a case study. On September 12, 2013, lightning struck within 300 m of the air traffic control (ATC) tower at BWI, causing injury and ATC tower and airport closures. The study findings reveal that the economic losses of the outage-related delays from that single event were almost five times higher than the ATC tower refurbishment that was planned, but unimplemented, in support of lightning protection, grounding, bonding, and shielding (LPGBS). The aim of this research is to support FAA's mission to better understand and quantify consequences of lightning strike–induced outages on airport performance. The research methodology and results can assist FAA in making sound decisions in support of LPGBS, and thereby help protect the National Airspace System infrastructure from lightning strikes and extreme weather and related delays.

Situational Leadership Styles in United States Air Force Air Traffic Control Towers

Leadership in air traffic control facilities is critical to the safe, orderly, and efficient flow of air traffic. The purpose of this qualitative study was to determine the preferred leadership style for United States Air Force air traffic control tower watch supervisors. A panel of 10 functional experts completed a 25 question scenario-based survey to establish a baseline for this study’s four research questions. A purposeful sample of eight control tower chief controllers representing the eight United States Air Force major commands were interviewed and their responses were compared to the mean of the experts panel. The data from the interviews was analyzed and in addition to the straight forward responses to the research questions two themes emerged: (1) the role of the monitor and (2) the apprentice controller’s role in emergency situations. The study discovered that United States Air Force control towers are fully implementing the fundamentals of situational leadership. The eight interviewees’ responses mirrored the expert panels’ answers. The results of this study provide control tower chief controllers, watch supervisors, and future watch supervisors a frame of reference on how situations are handled across the spectrum of facilities.

Security economics: an adversarial risk analysis approach to airport protection

We analyze the case of protecting an airport, in which there is concern with terrorist threats against the Air Traffic Control Tower. To deter terrorist actions, airport authorities rely on various protective measures, which entail multiple consequences. By deploying them, airport authorities expect to reduce the probabilities and potential impacts of terrorist actions. We aim at giving advice to the airport authorities by devising a security resource allocation plan. We use the framework of adversarial risk analysis to deal with the problem.

Performance Evaluation of SARDA: An Individual Aircraft-based Advisory Concept for Surface Management

Surface operations at airports in the US are based on tactical operations, where departure aircraft primarily queue up and wait at the departure runways. NASA’s Spot And Runway Departure Advisor (SARDA) tool was developed to address these inefficiencies through air traffic control tower advisories. The SARDA system is being updated to include collaborative gate-hold, either tactically or strategically. This paper presents the results of the human-in-the-loop evaluation of the tactical gate-hold version of SARDA in a 360° simulated tower setting. The simulations were conducted for the east side of the Dallas/Fort Worth airport. The new system provides gate-hold, ground controller and local controller advisories based on a single scheduler. Simulations were conducted with SARDA on and off, the off case reflecting current day operations with no gate-hold. Scenarios based on medium 1.2× current levels) and heavy (1.5× current levels) traffic were explored. Data collected from the simulation were analyzed for runway usage, runway queue size, delay for departures and arrivals, and fuel consumption. Further, traffic management initiatives were introduced for a subset of the aircraft. Results indicated that runway usage did not change with the use of SARDA, i.e., there was no loss in runway throughput as compared to baseline. At the same time, runway queue size did not exceed seven aircraft under SARDA, compared to a maximum of sixteen in the baseline. Taxiing delay was significantly reduced with the use of advisory by 45% in medium scenarios and 60% in heavy. Observed gate-holds were less than 15 minutes in all but one scenario, and even in this scenario 95% of the aircraft had a gate-hold of less than 15 minutes. Arrival delay was unaffected by the use of advisory. Total fuel consumption was also reduced by 23% in medium traffic and 33% in heavy traffic. TMI compliance appeared unaffected by the advisory.

Assessing Disability Glare Potential of Reflections from New Construction

Disability glare, or visual impairment due to extreme brightness or contrast, can be caused by intense reflections from new constructions onto existing transportation or building infrastructure located nearby. A case study analyzed a disability glare hazard at an airport created by the installation of a large array of photovoltaic panels between an air traffic control tower and the aircraft taxiway. The panels reflected blinding quantities of daylight into the control tower, produced temporary afterimages, and dangerously obscured taxiing aircraft. The existing FAA guidelines for installation of solar technologies are discussed relative to their shortcomings in identifying the glare hazard. High dynamic range photography was used to analyze the glaring situation at the airport. The authors proposed a maximum brightness threshold of 30,000 cd/m2 based on the physiology of human vision and the brightness of tasks necessary for air traffic controllers at the case study airport. Detailed reflectivity and three-dimensional models of the photovoltaic panels and the airport were created and validated against measured data. These models were used to perform an annual analysis of the glare hazard. This analysis is displayed temporally by graphs and spatially by images that indicate where the glaring reflections originate. Such information is useful in identifying potential for disability glare before new constructions are built. Finally, the authors used the new method to analyze designs for remediation of the glare hazard.

Human–Systems Integration Design Process of the Air Traffic Control Tower Flight Data Manager

A user-friendly system that yields operational benefit results from data-driven prototype evaluations and benefits analyses that iteratively feed back into the prototype design and development. In this study, initial requirements development and field evaluations were conducted using a shadow operations technique at the center tower backup Dallas–Fort Worth International Airport air traffic control tower (ATCT). Results are discussed in reference to the design process of the Tower Flight Data Manager (TFDM) prototype. Nonintrusive measures for quantitatively validating human–systems design issues were identified for this study, including visual gaze analysis and verbal command sequence analysis. Behavioral validation of design issues simplifies the process to prioritize beneficial design changes. The iterative process used resulted in an interim TFDM prototype that was rated by active air traffic controllers as both beneficial and usable in an operational ATCT environment.

Estimating the Monetizable Safety Benefits of Prototype Air Traffic Control Technologies

The Federal Aviation Administration (FAA) utilizes a formal investment analysis process to support the development, procurement and deployment of new air traffic control technologies. It is often unclear how to estimate the impacts of a new technology on aviation safety, both in terms of the probability that incidents and accidents could be prevented and in terms of the potential financial savings associated with reduced aircraft damage and personal injuries. With this in mind, the focus of this paper is twofold: (1) demonstrating the application of a method for generating probabilistic estimates of safety benefits for a future air traffic control technology, and (2) monetizing and extrapolating safety impacts from historical data to provide a quantitative estimate of savings over the lifetime of a new technology. The technologies explored in this analysis involve electronic flight data, enhanced surveillance and decision support tools for the air traffic control tower environment. From this initial analysis, the estimated total monetizable safety benefit of deploying all of these capabilities in a new system with an expected 2015-2035 lifetime across a set of major airports in the US ranges from $155 million to $2.1 billion. Implications of key data assumptions driving the lower and upper-bound estimates are discussed.

A Field Demonstration of the Air Traffic Control Tower Flight Data Manager Prototype

The development and evaluation process of the Tower Flight Data Manager prototype at Dallas Ft. Worth airport is described. Key results from the first field evaluation are presented, including lessons learned about making electronic flight information acceptable to controllers. Iteration of the field evaluation methods are discussed for practitioner benefit.

Relevance and Prestige of Information in Air Traffic Control Towers

The relevance and prestige of information relayed to air traffic controllers must work within the controllers’ existing communications framework. Relevance reflects the controller’s information needs; it is measured by the criticality of the information, its importance, and the number of tasks that use the information. Prestige reflects the extent to which the tower supplies the information; it is measured by the number of sources that display that information. Based on a previous task analysis, we analyzed details about (1) which control position uses the information, (2) the relevance of that information to the different tower positions as well as to the tower as a whole, and (3) the prestige of the information. Results indicated that although the local controller uses the majority of information available in the tower, there are also a considerable number of information objects used by all three tower positions. This information used universally tended to be about status and tower procedures. Primary target and the level of precipitation were the most relevant pieces of information used in the control tower. Mode-C altitude seemed to be the most prestigious piece of information. Overall, however, highly prestigious information tended also to be more relevant, suggesting the tower’s information architecture is reasonably well suited to meet the controllers’ information needs.

Air Traffic Controller Performance in a Human-in-the-Loop Virtual Tower Simulation

The Federal Aviation Administration is implementing the Next Generation of Air Transportation Systems, with greater reliance on surface surveillance sensors to provide a virtual representation to controllers of ground activity, reducing the need for controllers to look out-the-window (OTW). This study investigated how presently available technology can be used as a virtual control tower by the controller workforce. Thirty-two human-in-the-loop scenarios were conducted in an air traffic control tower simulator with different equipment configurations and under different operating conditions. Six recently retired controllers participated. Team performance on airport operations was comparable when surface surveillance information was provided, with or without the OTW view under good visibility. Advantages were found for surface surveillance when visibility was reduced. Mental workload was lower when surface surveillance was available under low visibility conditions, and reliance on radio communications also decreased. Subjective ratings indicate that controllers are most comfortable using some combination of existing technology and procedures for adapting to a virtual tower. The results are discussed with respect to future systems for controllers

Dimensions of air traffic control tower information needs: From information requests to display design.

In an effort to determine the information needs of tower air traffic controllers, instructors from the Federal Aviation Administration's Academy in Oklahoma City were asked to control traffic in a high-fidelity tower cab simulator. Information requests were made apparent by eliminating access to standard tower information sources. Instead, controllers were required to ask for precisely the information they needed during the scenarios. The information requests were classified using an elaboration of Zwaan and Radvansky's (1998) dimensions of situation models. The vast majority of requests were about three of the dimensions originally developed for reading comprehension: the protagonist, intentionality, and space. The information requests were also classified into 28 operational categories (e.g., aircraft identification, destination). From these results, the data were summarized, not just statistically, but by the creation of display-hypotheses. The display-hypotheses were organized according to the situation-model dimensions. Controllers preferred data blocks organized by the situation-model principle over those that violated this organization. The summary display-hypotheses were quite simple and accounted for the vast majority of the information requests controllers made. The display-hypotheses accounted for the information needs of controllers during routine as well as off-nominal events.

Real-Time Use of Paper in Air Traffic Control Towers: Criticality and Benefits

The purpose of this study was to gain a better understanding of how and why flight progress strips are currently used in air traffic control towers in the United States. The 3 main staffing positions in the tower, flight-data/clearance delivery (FD/CD), ground control (GC), and local control (LC), were observed by subject-matter experts at 10 control towers. Frequency of occurrence, importance ratings, and type of paper used were recorded. In addition, perceived benefits of marks made on the paper were assessed using open item responses and a series of Likert-scale questions. The positions varied in the marks the controllers made and in their reasons for making the marks. FD/CD controllers tended to make marks because they reduced workload or aided communication. LC tended to make marks because they aided memory, organization, and situation awareness. GC proved to be an interesting hybrid of the FD/CD and LC.

Novel steel cladding for air traffic control tower

The innovative design of 3DReid Architect's new air traffic control tower at Newcastle International Airport incorporates a steel façade that provides both additional function and cost savings.

Croatia Control selects RAD's Optimux to connect air traffic control towers

Croatia Control selects RAD's Optimux to connect air traffic control towers

Indoor air quality assessment in the air traffic control tower of the Athens Airport, Greece

In this study, an assessment of indoor air quality (IAQ) and thermal comfort in the Athens Traffic Control Tower (ATCT) offices of Hellinicon building complex, which is mechanically ventilated, is presented. Measurements of PM(10), PM(2.5), TVOCs and CO(2) concentrations were performed during three experimental cycles, while the Thom Discomfort Index was calculated to describe the employees' feeling of discomfort. The aim of the first cycle was to identify the IAQ status, the second to investigate the effectiveness of certain measures taken, and the third to continuously monitor and control IAQ. During the first two cycles, daily spot measurements of TVOCs and CO(2) were performed at various indoor locations and at the respective outdoor air intake positions, in addition with mean 24-h spot measurements of indoor PM(10) and PM(2.5). Results revealed that pollution levels vary according to the occupancy and the kind of activity. Following that, an automated system (IMAS) was designed and employed to continuously monitor indoor and outdoor CO(2), TVOCs, temperature and relative humidity. The ultimate scope was to control the IAQ and offer acceptable comfort conditions to the employees, whose work is of special nature and extremely demanding. Intervention scenarios were formulated and applied to the system to improve indoor conditions, when and where necessary. Regarding the third cycle, 1-year measurements collected from the system to examine its effectiveness. While it was shown that discomfort may be attributed to co-existence of unsatisfactory thermal comfort conditions and IAQ, usually the sole predominant factor of discomfort feeling is thermal comfort.

Developing a Decision Support Interface for Surface Domain Air Traffic Controllers

The effects of advanced automation tools on the air traffic control tower environment were assessed through a real-time simulation study. One focus of the study was the impact that advanced tools would have on controllers' roles and work patterns. Participants controlled simulated traffic during 45-minute scenarios, and reported their perceived workload and experience of using a prototype automation tool. Perceived workload was significantly reduced in the advanced automation conditions, more so as the automation assumed more functions. Participants interacted a great deal with the automation in these conditions, a notable proportion of which was interface management. Despite generally liking the tool, controllers reported the automation had assumed all of their role's decision-making responsibilities and left them with mechanical tasks. It is concluded that a more artful allocation of functions is required if controllers are to be engaged in their task when using advanced automation tools.

Aluminium Stair and Lift Load-Bearing Core of the Barcelona Airport Tower

The new air-traffic control tower at Barcelona airport features significant structural details, among which is the innovative interaction of supporting elements in white prefabricated concrete and the aluminium core (Fig. 1). The two materials were selected for their corrosion resistance, which makes them suitable for load bearing ele ments in an area close to the seashore. This selection met the request for material durability specified by the client. This paper mainly deals with the aluminium stairway.