US Airspace Research Articles

Portraying the Geography of US Airspace with 3-Dimensional GIS-Based Analysis and Visualization

The United States identifies, monitors, and defends a vast network of controlled airspaces surrounding its own and allied territories. These controlled airspaces include civilian aviation classes (A through G), drone flying regions, and special use (military) air classifications. These controlled spaces are invisible to the naked eye and often go unnoticed. Managing and portraying data that function in two and three dimensions poses significant challenges that have hindered prior analyses or geovisualizations of controlled airspaces, but we demonstrate here how many of these can be surmounted to visually represent the spatial extent and patterns of US-controlled airspace. In this paper, we demonstrate how these complex spaces can be graphically represented and highlight how cartographic and geovisual representations of often-overlooked domains contribute to a richer understanding of the reach and character of US airspace. The methods described for this work can be extended to other types of multidimensional objects and may facilitate more robust considerations of how Geographical Information Science (GIS) can be useful in analyzing and depicting airspace and territorial claims in three dimensions.

Deflating the Chinese balloon: types of Twitter bots in US-China balloon incident

As digitalization increases, countries employ digital diplomacy, harnessing digital resources to project their desired image. Digital diplomacy also encompasses the interactivity of digital platforms, providing a trove of public opinion that diplomatic agents can collect. Social media bots actively participate in political events through influencing political communication and purporting coordinated narratives to influence human behavior. This article provides a methodology towards identifying three types of bots: General Bots, News Bots and Bridging Bots, then further identify these classes of bots on Twitter during a diplomatic incident involving the United States and China. In the balloon incident that occurred in early 2023, where a balloon believed to have originated from China is spotted across the US airspace. Both countries have differing opinions on the function and eventual handling of the balloon. Using a series of computational methods, this article examines the impact of bots on the topics disseminated, the influence and the use of information maneuvers of bots within the social communication network. Among others, our results observe that all three types of bots are present across the two countries; bots geotagged to the US are generally concerned with the balloon location while those geotagged to China discussed topics related to escalating tensions; and perform different extent of positive narrative and network information maneuvers. The broader implications of our work towards policy making is the systematic identification of the type of bot users and their properties across country lines, enabling the evaluation of how automated agents are being deployed to disseminate narratives and the nature of narratives propagated, and therefore reflects the image that the country is being projected as on social media; as well as the perception of political issues by social media users.

When They "Come From Away" Every Day.

When They "Come From Away" Every Day.

Adaptation as a source of safety in complex socio-technical systems: A literature review and model development

Recent advances in safety science point towards a different approach to the management of risk within safety-related industries that focusses on successfully harnessing the adaptations present within complex socio-technical systems. However, adaptation is a concept with a variety of interpretations that impairs the ability of industrial practitioners to understand and apply this concept to the management of safety. We present a systematic review of the safety literature using a grounded theory approach from a variety of industrial domains and theoretical standpoints to identify the key features within complex socio-technical systems that describe how adaptation and safety are related. A model for adaptation, developed from these ideas, is then described. This model is then used to explain the response of UK oceanic air traffic controllers to the closure of US airspace following the terrorist attacks in the US on the 11th September 2001. The case study highlights how the model aids an enquiry into the features of adaptation that are present within complex socio-technical systems. The review also identifies the need for further research to assist industrial practitioners connect the role of adaptation at the level of the individual to the adaptive capacity at the level of the organisation.

Modelling the asymmetric probabilistic delay of aircraft arrival

The main purpose of this paper is to present an asymmetric logit probability model to estimate and predict the daily probabilities of delay in aircraft arrivals. The proposed model takes into account statistical regularity, noting that more arrivals are on time than delayed, thus reflecting an asymmetric pattern of behaviour. The data analysed were obtained from the BTS and IATA databases for December 2014, corresponding to delays within the US airspace system for each carrier, measured at various US airports. The model was evaluated by analysing both in–sample and out–of–sample data, for main and control samples. The performance of the proposed asymmetric Bayesian logit model was compared with that of two others: frequentist logit and symmetric Bayesian logit. The main conclusion drawn is that the model we propose obtains the best fit, according to the statistics considered, and identifies a novel delaying factor, namely distance, which is not identified by the other models analysed.

Verification column

The technical column on verification presents an invited contribution by César A. Muñoz, Aaron Dutle, Anthony Narkawicz, and Jason Upchurch at NASA Langley Research Center titled Unmanned Aircraft Systems in the National Airspace System: A Formal Methods Perspective in the July issue of the SIGLOG newsletter. In the past few years we have seen a dramatic increase in the number of hobbyist unmanned aircraft systems (UAS). In addition we have seen a push by several companies including Amazon to use UAS as a package delivery mechanism. The increasing numbers of UAS in our current airspace have introduced a new safety challenge. There have been some high-profile incidents that were reported widely in the media. One example was a drone being 100 feet within an commercial airliner at the JFK airport in New York in Aug 2015, while another was a near miss at the Los Angeles airport between a Lufthansa passenger jumbo jet and a UAS in March 2016. These are however not isolated incidents. The Federal Aviation Administration (FAA) records shows that there are hundreds of close calls between airplanes and UAS in the US airspace. Similar reports have been documented in the UK and Europe. This safety concern has prompted the development of a detect and avoid capability for the UAS that is designed to avoid aircraft in its vicinity. The article presents the work being done at the NASA Langley Research Center Formal Methods group in Hampton Virigina. I am very excited for this article to appear in the SIGLOG newsletter. This article I believe will be of interest to people not only in the logic, formal methods, and verification community but a broader and more general audience as well.

Filtering Enhanced Traffic Management System (ETMS) Altitude Data

Abstract Enhanced Traffic Management System (ETMS) stores all the information gathered by the Federal Aviation Administration (FAA) from aircraft flying in the US airspace. The data stored from each flight includes the 4D trajectory (latitude, longitude, altitude and timestamp), radar data and flight plan information. Unfortunately, there is a data quality problem in the vertical channel and the altitude component of the trajectories contains some isolated samples in which a wrong value was stored. Overall, the data is generally accurate and it was found that only 0.3% of the altitude values were incorrect, however the impact of these erroneous data in some analyses could be important, motivating the development of a filtering procedure. The approach developed for filtering ETMS altitude data includes some specific algorithms for problems found in this particular dataset, and a novel filter to correct isolated bad samples (named Despeckle filter). As a result, all altitude errors were eliminated in 99.7% of the flights affected by noise, while preserving the original values of the samples without bad data. The algorithm presented in this paper attains better results than standard filters such as the median filter, and it could be applied to any signal affected by noise in the form of spikes

An analysis of air traffic controller-pilot miscommunication in the NextGen environment

This paper extends research on miscommunication between air traffic controllers and pilots by developing statistical models that predict the outcome of communications within the scope of controller-pilot data communications in the Next Generation Air Transportation environment. A database of controller-pilot voice messages from high and super-high altitude en-route sectors of US airspace is investigated. Emphasis is given to parameters that can be utilized in the voice-only communication, as well as in the mixed media, environment. This allows formulation of reasonable assumptions about the impact of data communications on controller and pilot behavior. The models indicate that the most important factors affecting communications are length and context of the message, entering of an aircraft into a sector, transfer of communication, and radio frequency congestion. The results also suggest that the transmission of non-time critical routine messages via data communications could reduce the number of communication errors and alleviate radio frequency congestion.

May the US government monitor private critical infrastructure assets to combat foreign cyberspace threats?

The government “owns” the entire US airspace–it can install radar systems, enforce no-fly zones and interdict hostile aircraft. Since the critical infrastructure and the associated cyberspace are just as vital to national security, could the US government protect major assets–including privately-owned assets–by positioning sensors and defensive systems? This paper discusses the legal issues related to the government’s deployment of sensors in privately owned assets to gain broad situational awareness of foreign threats. This paper does not necessarily advocate pervasive government monitoring of the critical infrastructure; rather, it attempts to analyze the legal principles that would permit or preclude various forms of monitoring.

A multiagent approach to managing air traffic flow

Intelligent air traffic flow management is one of the fundamental challenges facing the Federal Aviation Administration (FAA) today. FAA estimates put weather, routing decisions and airport condition induced delays at 1,682,700 h in 2007 (FAA OPSNET Data, US Department of Transportation website, http://www.faa.gov/data_statistics/ ), resulting in a staggering economic loss of over $41 billion (Joint Economic Commission Majority Staff, Your flight has been delayed again, 2008). New solutions to the flow management are needed to accommodate the threefold increase in air traffic anticipated over the next two decades. Indeed, this is a complex problem where the interactions of changing conditions (e.g., weather), conflicting priorities (e.g., different airlines), limited resources (e.g., air traffic controllers) and heavy volume (e.g., over 40,000 flights over the US airspace) demand an adaptive and robust solution. In this paper we explore a multiagent algorithm where agents use reinforcement learning (RL) to reduce congestion through local actions. Each agent is associated with a fix (a specific location in 2D space) and has one of three actions: setting separation between airplanes, ordering ground delays or performing reroutes. We simulate air traffic using FACET which is an air traffic flow simulator developed at NASA and used extensively by the FAA and industry. Our FACET simulations on both artificial and real historical data from the Chicago and New York airspaces show that agents receiving personalized rewards reduce congestion by up to 80% over agents receiving a global reward and by up to 90% over a current industry approach (Monte Carlo estimation).

Improving Air Traffic Management with a Learning Multiagent System

A fundamental challenge facing the aerospace industry is efficient, safe, and reliable air traffic management (ATM). On a typical day, more than 40,000 commercial flights operate in US airspace, and the number of flights is increasing rapidly. This paper shows how learning multiagent system helps improve ATM.

Air transport cruise altitude restrictions to minimize contrail formation

While quantification of the effects of NO x and water vapor is still at an early stage there is evidence that contrail formation could make a significant contribution to global warming. This paper builds on previous research that analyzed a policy of restricting air transport cruise altitudes to eliminate contrail formation. Our previous work [Transport. Res. D 7(6) (2002) 451], examined altitude restrictions in European airspace and concluded that this could be a beneficial policy for reducing climate change impacts from aviation. Since most of the flights in European airspace are short-haul flights, this paper evaluates the trade-offs between altitude restrictions, fuel burn and journey times for longer haul flights of up to 6000 nm. Our focus is on the North Atlantic and US airspace and we examine potential contrail fraction to determine optimal cruise altitudes for reducing contrail formation. Changes in fuel burn and travel times associated with flight levels of 18,000 and 31,000 ft for different aircraft types are analyzed. We find that, in most cases, CO 2 emission increases would be unlikely to entirely counteract the benefit of possible reductions in contrail formation. For some aircraft types, the percentage increase in emitted CO 2 was found to be strongly dependent on journey length. In general, journey times appear not to be a major issue except for some aircraft types. Our results suggest that reducing aircraft cruise altitudes could be a beneficial policy for mitigating climate change impacts from the aviation sector. This is clearly dependent on aircraft type and the distances traveled, but more importantly on ambient atmospheric conditions which can vary significantly between regions and due to daily variation. This suggests that real time flight planning to minimize contrail formation should be investigated as a possible climate mitigation policy.

Air transport cruise altitude restrictions to minimize contrail formation

While quantification of the effects of NO x and water vapor is still at an early stage there is evidence that contrail formation could make a significant contribution to global warming. This paper builds on previous research that analyzed a policy of restricting air transport cruise altitudes to eliminate contrail formation. Our previous work [Transport. Res. D 7(6) (2002) 451], examined altitude restrictions in European airspace and concluded that this could be a beneficial policy for reducing climate change impacts from aviation. Since most of the flights in European airspace are short-haul flights, this paper evaluates the trade-offs between altitude restrictions, fuel burn and journey times for longer haul flights of up to 6000 nm. Our focus is on the North Atlantic and US airspace and we examine potential contrail fraction to determine optimal cruise altitudes for reducing contrail formation. Changes in fuel burn and travel times associated with flight levels of 18,000 and 31,000 ft for different aircraft types are analyzed. We find that, in most cases, CO2 emission increases would be unlikely to entirely counteract the benefit of possible reductions in contrail formation. For some aircraft types, the percentage increase in emitted CO2 was found to be strongly dependent on journey length. In general, journey times appear not to be a major issue except for some aircraft types. Our results suggest that reducing aircraft cruise altitudes could be a beneficial policy for mitigating climate change impacts from the aviation sector. This is clearly dependent on aircraft type and the distances traveled, but more importantly on ambient atmospheric conditions which can vary significantly between regions and due to daily variation. This suggests that real time flight planning to minimize contrail formation should be investigated as a possible climate mitigation policy.

Pricing-Based Solutions to the Problem of Weather-Related Airport and Airway System Delay

This paper explores the applicability and feasibility of using pricing-based mechanisms for allocating capacity and managing demand in the airport and airway system during periods of weather-related disruption. It begins with a general analysis of the economics and dynamics of congestion-related delay that identifies to efficiency gains that are potentially realizable though better management of the congested traffic stream. It then explores the causes of delay within the airport and airway system. Three forms of congestion are identified: scheduling practices that concentrate more takeoffs and landings during key time periods than an airport can accommodate; stochastic fluctuations in the traffic stream that cause demand for some system component to temporarily exceed its capacity; and disruptions-primarily weather related-that temporarily reduce the capacity of system components. Although the published literature on the use of congestion pricing in the aviation context has focused almost exclusively on overscheduling, review of operational data suggests that weather related disruptions are a far more significant source of delay. The paper reviews the procedures currently used within US airspace to manage traffic during periods of disruption, and identifies inefficiencies attributable to the failure of those procedures to allow a full set of trades between airlines that may have different need for immediate use of the limited capacity that is available during such periods. The paper concludes with an exploration of some of the operational issues associated with the use of pricing on a real-time basis to allocate limited system capacity. This review draws on the experience of another industry–the electric power industry–that has developed workable procedures for using pricing signals to balance supply and demand within a complicated system on a real-time basis.

Development of Improved TCAS II Surveillance and Interference Limiting Functions

This paper describes the development and validation of improved TCAS II intruder surveillance tracking and interference limiting algorithms. Improvements in interference limiting were prompted by the FAA Spectrum Management Office and by international aviation administrations in order to further reduce interference to ground-based air traffic control surveillance by TCAS II. Improvements in surveillance tracking were prompted by aircarrier pilot organizations in order to increase the level of traffic situational awareness offered by the TCAS II display. The new algorithms are included in a proposed new version of TCAS II MOPS DO-185A which is commonly referred to as Change 7.0. TCAS II change 7.0 units will be introduced into the US airspace beginning as early as 1999 as part of a program to implement improvements in both TCAS II surveillance and collision avoidance.

Performance Analysis of a Horizontal Miss Distance Filter for TCAS II

This paper describes the performance of a filter for reducing unnecessary alerts from the Traffic Alert and Collision Avoidance System (TCAS). The filter uses range and bearing measurements to estimate miss distance for potential threat aircraft. When the estimated miss distance is high, TCAS resolution advisories are suppressed. The filter has been prototyped and extensively tested in MITRE’s TCAS simulation test bed. When implemented, the filter is expected to reduce TCAS resolution advisories by about 25% in US airspace and by about 40% in European airspace, while having a negligible effect on system safety. The filter will be included in the next fielded version of TCAS.

AI for air traffic

The Federal Aviation Administration (FAA) air traffic control (ATC) system operates the US airspace for all users (commercial, corporate, government, military, and general aviation). The system includes such elements as the central flow control facility, en-route centers, flight service stations, terminal facilities, and airport towers. The example presented describes an application of a knowledge-based system for nationwide air traffic management operations. >

Appendix B: Statement of DOD principles for news media coverage of DOD operations

In Emerging Issues in Airport Operations, Safety, and Emergency Management, the future of Airport Operations, safety, and emergency management is shown to evolve in ways that will support new advents, such as Unmanned Aerial Vehicles (UAVs), commercialized aerospace systems, and innovative methods in airport emergency/incident management. UAVs have deployed throughout the US airspace system at rates faster than government can effectively regulate. Challenges include small UAVs operating near airports, by individuals who perhaps do not understand or abide by the regulations on such operations; and large UAVs that can present greater operational and safety challenges to airports and aircraft. Alternatively, UAVs also represent a significant potential source of revenue for airports. In addition to the adoption of UAVs, advancing technology and the cessation of the US Space Shuttle have opened new opportunities for the private commercial space industry operating at commercial airports. Several US airports have been designated or are seeking status as FAA-certified spaceports (see included case study of Front Range Airport, Denver, Colorado). There have been several flight tests of spacecraft designed to eventually take space tourists on suborbital flights. Commercial launch missions have been successful at servicing the International Space Station. Parallel to these innovations, it is vital that operational personnel and emergency Incident Commanders improve their understanding of psychological dynamics during high-risk/high-stress operations. Continuous improvement and delivery of training and exercises for operational personnel and emergency responders are now an absolute requirement in all areas of the aviation and aerospace industries.