Introduction
Free Flight air traffic control system plan was first proposed in the mid-1990s when the U.S. officials recognized the need for a more cost-effective method of governing the airspace. However, to this day, a comprehensive system for flight control automation has not been implemented due to several challenges. In the upcoming decades, air traffic demand is anticipated to grow further: “The Federal Aviation Administration (FAA) projects in its aerospace forecast for 2008-2025 that 78.0 million aircraft will be handled by FAA en route traffic control centers in 2025, as compared to 46.8 million aircraft handled in 2007” (Prevot, Homola, Mercer, Mainini, & Cabrall, 2009, p. 1). The increase in air traffic intensity will put more pressure on Air Traffic Control (ATC) operators, who are already overwhelmed with the amount and complexity of tasks at hand (Gorodetsky, Karsaev, Samoylov, & Skormin, 2008). More dangers to the ATC operators’ performance, however, are posed by the growing frequency of non-standard events, such as hijacking (Gorodetsky et al., 2008), technical failures, and deliberate faulty actions of pilots and crew, such as during the May 2015 Germanwings Flight 9525 crash. The emotional tension present in such situations makes it difficult for human ATC operators to govern and resolve the conflicts efficiently. An automated system, on the other hand, is believed to eliminate the human error factor in the decision-making process, thus ensuring the successful management of non-standard situations. Nevertheless, with the current state of automated air traffic control development, it is unlikely that the system can be correctly implemented in the next ten to fifteen years. There are also additional challenges that, I believe, may impair the success of the initiative. In this project, I aim to describe the potential benefits and difficulties that the introduction of a Free Flight system will incur.
Potential Benefits of Free Flight
Lower Rate of Mistakes
The main reason for the implementation of an automated air traffic control system is to lower the incidence of mistakes made during the traffic flow management process and decision-making. The airborne separation assurance system (ASAS), which is one of the main components of the Free Flight system, will be responsible for conflict detection and resolution (Alam, Shafi, Abbass, & Barlow, 2009). In the case of serious risk of conflicts, the ATC operators will be able to respond more quickly and efficiently, as their workload will be significantly lower (Langan-Fox, Canty, & Sankey, 2009). Studies prove that medium-term conflict detection and resolution automation was useful in resolving 98% of conflicts during nominal operations at 2x and 3x traffic densities (Prevot et al., 2009). With support from automated systems, controllers were able to resolve 75% of the off-nominal short-term conflicts (Prevot et al., 2009), which means that the rate of failures and misses in conflict resolution will indeed be lower if at least some degree of automation is provided.
Higher Cost-Efficiency
It is generally accepted that the automation of operations provides cost-saving benefits in the vast majority of circumstances, including air traffic control. In the case of Free Flight, the lower rate of mistakes and the more effective choice of route will account for decreased fuel burn, lower environmental impact (Prevot, Homola, Martin, Mercer, & Cabral, 2012), as well as fewer flight delays and cancellations. Together with decreased staff needs, these features are likely to save billions of dollars for the airports, flight companies, and other involved entities. These savings could be used to modernize aircraft and airport sites, improving their safety and security, which is one of the highest priorities in the contemporary air travel business.
Increased Control by the Pilots
As a result of the automation of ATC, more control will be given to pilots and crews, including in conflict management (Alam et al., 2009). This will further increase the availability of operators for the cases requiring urgent action (Langan-Fox et al., 2009). Moreover, “In Free Flight, pilots will have the freedom to choose their trajectory and speed in real-time to maximize their flight objectives while maintaining safe separation from neighboring traffic” (Alam et al., 2009, p. 298). The increase in control given to pilots and the crew will result in greater security on a wide variety of routes. Furthermore, it will decrease the possibility of misses by the ATC operators affecting the safety of the flight, as pilots will have more flexibility in responding to a risky situation.
Increased Capacity
Studies suggest that the route capacity will increase dramatically as a result of automated traffic control (Prevot et al., 2009). Researchers agree that “The main factor limiting en-route capacity is controller workload associated with providing safe separation between aircraft” (Prevot et al., 2009, p. 1). The increase in capacity, in this case, will be provided by decreasing the workload of the ATC operators and ensuring that the automated systems are capable of handling a steep increase in the aircraft density en route (Prevot et al., 2009). Growing the capacity of the ATC process is essential to provide a safe environment for the increasing number of flights, aircraft, and routes, which is inevitable due to the development of tourism all over the world and the improvement in air travel demand, both in developed and developing countries.
Challenges
Low Trust in Technology
Even though human errors account for the majority of potential airplane crashes and collisions, most people are still skeptical of relying on technologies for their safety. Therefore, some form of human control will probably remain in place to govern the technology, which will also provide opportunities for human errors. However, this paradox has already been addressed in research. For instance, Higham, Vu, Miles, Strybel, and Battiste (2013) explain that a comprehensive training will result in higher trust in technology while at the same time preventing most of the human mistakes that may occur during its use.
Underdevelopment of Components
One of the major concerns about the Free Flight system adoption is the underdevelopment of the components that are crucial to its functioning. For instance, the Automatic Dependent Surveillance-Broadcast (ADS-B) system is at the core of all automated traffic management enterprises (Strohmeier, Schafer, Lenders, & Marticovic, 2014). It allows the aircraft to broadcast their locations and route plans in current time, thus enhancing situational awareness and the capability of the ATC to indicate and resolve traffic conflicts (Strohmeier et al., 2014). However, there are some major security considerations applicable to the current state of ADS-B technology. For instance, there is a relatively high incidence of message loss; the system is also susceptible to RF attacks and functions via an unstable data link, which may lead to serious accidents, such as aircraft disappearances, collisions, and airplanes spoofing (Strohmeier et al., 2014). Costin and Francillon (2012) also highlight that the ADS-B has no security mechanisms in place, which may avert the flight security improvements made as a result of the ATC automation.
Impaired Performance
Some studies show that the automation of ATC processes may lead to impaired performance of pilots and controllers. For instance, in a study by Vu et al. (2012), the researchers found that the pilots who received conflict resolutions from an automated system were less capable of performing various flight tasks, such as en-route and arrival spacing, weather avoidance, and continuous descent arrival than those who received instructions from an operator (Vu et al., 2012). Another study by Rovira and Parasuraman (2010) suggested that the use of imperfect automation in the ATC processes was associated with a decline in conflict detection compared to manual task performance and had a major effect on the success of the operator’s actions. This shows that the introduction of an underdeveloped technology may reduce the success of incident responses and impair the security of travel.
Conclusion
Overall, I believe that, in the current stage of development, the Free Flight system will have far more implications than benefits. Whereas the system will decrease the costs for air travel companies and reduce the workload of the ATC personnel, it may create additional risks for the security of passengers and aircraft, particularly due to the underdevelopment of its components. One of the alternative ways to increase the effectiveness of ATC is to introduce partial automation using reliable technologies; the comprehensive introduction of the Free Flight system, on the other hand, should be postponed until all of the technologies involved are proven to be reliable and efficient.
References
Alam, S., Shafi, K., Abbass, H. A., & Barlow, M. (2009). An ensemble approach for conflict detection in free flight by data mining. Transportation Research Part C: Emerging Technologies, 17(3), 298-317.
Costin, A., & Francillon, A. (2012). Ghost in the Air (Traffic): On insecurity of ADS-B protocol and practical attacks on ADS-B devices. In Black Hat USA (pp. 1-12). Web.
Gorodetsky, V., Karsaev, O., Samoylov, V., & Skormin, V. (2008). Multi-agent technology for air traffic control and incident management in airport airspace. In Proceedings of the International Workshop Agents in Traffic and Transportation, Portugal (pp. 119-125). Web.
Higham, T. M., Vu, K. P. L., Miles, J., Strybel, T. Z., & Battiste, V. (2013). Training air traffic controller trust in automation within a nextgen environment. International Conference on Human Interface and the Management of Information (pp. 76-84). Berlin, Germany: Springer.
Langan-Fox, J., Canty, J. M., & Sankey, M. J. (2009). Human–automation teams and adaptable control for future air traffic management. International Journal of Industrial Ergonomics, 39(5), 894-903.
Prevot, T., Homola, J., Mercer, J., Mainini, M., & Cabrall, C. (2009). Initial evaluation of NextGen air/ground operations with ground-based automated separation assurance. In Eighth USA/Europe Air Traffic Management Research and Development Seminar, Napa, CA. Web.
Prevot, T., Homola, J. R., Martin, L. H., Mercer, J. S., & Cabrall, C. D. (2012). Toward automated air traffic control — Investigating a fundamental paradigm shift in human/systems interaction. International Journal of Human-Computer Interaction, 28(2), 77-98.
Rovira, E., & Parasuraman, R. (2010). Transitioning to future air traffic management: Effects of imperfect automation on controller attention and performance. Human factors, 52(3), 411-425.
Strohmeier, M., Schäfer, M., Lenders, V., & Martinovic, I. (2014). Realities and challenges of nextgen air traffic management: The case of ADS-B. IEEE Communications Magazine, 52(5), 111-118.
Vu, K. P. L., Strybel, T. Z., Battiste, V., Lachter, J., Dao, A. Q. V., Brandt, S., & Johnson, W. (2012). Pilot performance in trajectory-based operations under concepts of operation that vary separation responsibility across pilots, air traffic controllers, and automation. International Journal of Human-Computer Interaction, 28(2), 107-118.