Predictive Weather Display in ATC: Implications for Research and Training
Two systems are central to the Next Generation Air Transportation System (NextGen) air traffic management program Traffic Management Advisor (TMA) and En Route Automation Modernization (ERAM) One purpose of both systems is to reduce air traffic control (ATC) delay. The present study reports on an exploratory integration of convective weather, a major source of delay, into the ATC systems to allow early re route around weather in order to reduce delay. Pseudo controllers ran a series of simulation based scenarios with screen capture and video collection to assess delay and safety performance. Results provide evidence that delay was reduced by early rerouting in response to convective weather predictions. Implications for training and research are discussed. With air traffic for the United States projected to increase by a factor of two to three by 2025, the air traffic management system is facing a serious capacity crisis (FAA Fact Sheet, 2007) One way of addressing this crisis is through the construction ofnew airports and runways. While additional physical capacity will probably be necessary, a second option is to create new capacity in the National Air Space @AS) through the application of technology. The Next Generation Air Transportation System, commonly called NextGen, is the overarching answer of the US Federal Aviation Administdon (FAA) to the capacity and technology challenges facing the NAS in the 2lS century. As envisioned, NextGen will not only increase the capacity of the air transportation system, it will increase safety and security as well. At least two decision support tools (DSTs) are vital to the success of the NextGen Air Traffic Management (ATM) system Traffic Management Advisor (TMA) and En Route Automation Modernization (ERAM) Since Because adverse weather is a major cause of accidents and a primary source of delay and disruption in air traffic flow, the prediction and integration of weather into the air traffic control system is viewed as another critical component of the NextGen system (Bureau of Transportation Statistics, 2010; Levin, 2007) As envisioned, there would be a commonly displayed weather view on both TMA and ERAM systems that could be 'moved forward' in time up to six hours from the current operating time. This forward look would help controllers to adjust traffic (amend flight plans) to minimize delays and safety hazards (FAA NextGen Fact Sheet, 2007) To understand the current project, it is necessary to briefly describe TMA, ERAM and the envisioned operation of both software systems in the NAS. Subsequently, we describe the goal of extending the capabilities of these systems to reduce weather related di ce of traffic flows. Traffic Management Advisor The purpose of TMA is to assist air management perso~lnel in the management of arrival and departure flows, allowing them to reduce delay by maximizing capacity (number of aircraft) over specified metering fixes. A metering fix is a set point along an established route over which an aircraft is passed prior to entering the terminal airspace. At present, metering is performed for both arrival and en route points. The Terminal Radar Approach Control (TRACON) directs arriving traffic to one of the metering fixes munding the airport. In most cases, several streams of arriving traffic must be merged into a single line before crossing each metering fix. The computational engine of TMA, the Dynamic Planner @P) is responsible for computing the sequences and schedules of arriving aircraft. TMA receives a flight plan from one of the 20 traffic centers via the Host Computer System (HCS) or its replacement, the ERAM system, and calculates the route offlight, determhhg which flights are in the same stream at the metering fix. TMA then JAAER, Winter 201 1 Page 29 29 Rhoades and Neville: Predictive Weather Display in ATC: Implications for Research and Published by Scholarly Commons, 2011 Predictive Weather Disploy in A X generates the trajectories of each aircraft and displays a timeline showing when each the aircraft should arrive at a given metering fix. Aircraft arrival times are calculated well in advance of the actual arrival to allow for efficient coordination and delay allocation across sectors in multiple en route centers. TMA calculates an Estimated Time of Arrival (ETA) at various points along the route of flight, resulting in a four dimensional (4D) trajectory model. The Scheduled Time of Arrival (STA) at each point is calculated based on the ETA. Scheduling constraints may also be entered by the Traffic Management Coordinator (TMC) to reflect such factors as airport o g u r a t i o n and airport acceptance rates. The TMA system was deployed in all air route traffic control centers (ARTCCs) by March 2007. En Route Automation Modernization ERAM is the replacement for the old Host Computer System (HCS) that provides automated flight data processing services to support air traflic control. In addition to maintaining the current functionality of the HCS, ERAM improves information security, streamlines traffic flow, processes flight radar data, provides communication support, and generates display data. It integrates a series of new tools into the tactical (R controller) and slrategic @controller) air traffic control consoles. With ERAM, the air tdc control consoles can be configured to allow a single person to access both strategic and tactical data and decision support tools. Views provide the traditional situation display, display control and status, time, aircraft lists, flight plan readouts, and trial planning. In addition, window sizing, hiding, and positioning can be used to minimize clutter on the screen. Tool bars, pull down menus, and templates minimize the amount of data the controllers must enter to access information and update flight data. ERAM also provides support for the air traflic supervisor, flight data communication specialists, tracker position (also known as the hand off or H position) and t d E c flow management position. The overall goal of NextGen is to provide as much common situational awareness as possible to all these personnel; thus, many of the automation tools and displays are accessible upon request (Nolan, 2004) ERAM was operationally tested at the FAAs William J. Hughes Technical Center in Atlantic City before deployment to Salt Lake City in late 2008 and is scheduled for deployment to all 20 ARTCCs in 200920 10 h t t p f a a g v r t s r t s h n o l o g y Weather in the NAS Hazardous weather is a major source of delay as well as accidents and reducing both of these problems is part of the FAA weather initiatives (Bureau of Transportation Statistics, 2010; Levin, 2007) If certain weather conditions could be predicted and those predictions made available to aviation decision makers in a timely manner, then early action could be taken to avoid the hazard, reducing delay and accident rates. One such adverse condition is convective weather (i.e. thunderstorms) and one means of making the information available to aviation decision makes is to integrate predictive weather into the ERAM and TMA systems, providing common situational awareness, an ability to plan avoidance trajectories, and the capability of communicating these changes between ERAM and TMA so that times of arrival can be adjusted. The Concept of Operations for NextGen, prepared by the Joint Planning and Development Office (JPDO, 2009) defines the primary role for weather information as enabling "the identification of optimal trajectories that meet the safety, comfort, schedule, efficiency, and environmental impact requirements of the user and the system' This information should be 'supported by a set of consistent, reliable, probabilistic forecasts, covering (three dimensional space) timing, intensity, and the probability of all possible outcomes, eachwith an associated likelihood of occtu nmce" (p. 5 1 1) Further, a common weather picture that draws together multiple sources of weather information is identified as vital. Human Technology Integration Issues This study involves assessing the integration of predictive weather technology with ERAM and TMA air traffic control systems. Although the focus of the data collection is on flight control efficiency effects associated with technology integration, there are human technology integration issues that could influence the outcome. New technology often changes the nature of the work and thereby changes the ways in which co workers interact. For example, Wiener et al. (1991) found different communications patterns between the captain and first officer in a traditional versus a glass cockpit aircraft. In the traditional cockpit, the captain was issuing commands in the glass cockpit, the captain was more often asking questions. Organizational and social changes such as these can affect mentoring, morale, and the willingness and ability ofco workers to back each other up, ultimately negating any benefit of new technology, as d e s c r i i in the classic analysis of coal mine mechanization by Trist and Bamforth (1951) Further, new technology has the potential to relieve workload in one area while increasing workload in some other place (e.g. Bainbridge, 1983; Sarter, Billings, Woods, 1997) For example, predictive weather technology may increase controller workload by introducing uncertainty and thus greater information search or communication work into controller decision processes. Another potential unintended consequence of new technology is to benefit easy tasks while complicating more difficult tasks, as expresd by Weiner andhis colleagues (1991) ".pilots of advanced technology aircraft expressed the feeling that dmbg periods where the workload was high, the automation Page 30 JAAER, Winter 201 1 30 Journal of Aviation/Aerospace Education Research, Vol. 20, No. 2 [2011] Art. 7 https:/commons.erau.edu/jaaer/vol20/iss2/7 DOI: https:/doi.org/10.