Air Traffic Management Concepts Research Articles

New Generation Space Vehicle Operations in the United Arab Emirates – An Airspace and Risk Assessment

Air Transport is a highly technocentric and rapidly evolving industry. While certain legacy systems persist, more advanced technological concepts for carrying payloads and passengers further, faster, and more efficiently place this particular industry at the forefront of the most cutting-edge research and development initiatives in the fields of autonomous systems, artificial intelligence, cybersecurity, and advanced communication, navigation, surveillance applications. While drone technologies and applications have been widely and comprehensively addressed in recent years, the incipient hypersonic and suborbital commercial transport sector has received disproportionately less academic attention. Although certain suborbital passenger transport concepts such as the German Aerospace Center’s SpaceLiner are proposed for the more distant future, other concepts have reached operational status. A recent addition into the foray has been Blue Origin and its vertically launched New Shepherd autonomous vehicle. The United Arab Emirates, an increasingly active spacefaring nation, has signaled its interest. Among the nation’s highly ambitious short and long-term initiatives is the idea of launching space tourism flights from its own soil. Blue Origin, along with other candidates, has emerged as a contender to operate its New Shepard vehicle from a UAE-based spaceport. This paper explores how Next Generation Space Vehicle Operations (NGSVO) could impact a highly dense and compact airspace when operating from and to a UAE spaceport. Preliminary results suggest that under certain circumstances, NGSVOs may indeed affect existing Air Traffic Management (ATM) operations and pose increased safety risks while leading to higher fuel consumption and larger carbon dioxide footprints of regular air traffic. To establish a benchmark for future comparisons, the current study applies traditional airspace segregation methods to the UAE airspace to accommodate a specific type of NGSVO. Operational gains may be deduced by comparing the results of future studies applying more advanced ATM concepts to those reported in the current study.

Conflict Free Flight Path: A Design Study for Automation

A number of future air traffic management concepts are being studied to enhance efficiency and flight safety. Conflict Detection and Resolution (CDR) is one such initiative for operation much beyond the capability of the conventional Traffic Collision Avoidance System where the resolutions are generally in terms of changing speed or heading depending upon the situation. The design studies presented in this paper investigate possibility of generating heading change commands and integrating with Autopilot for closed loop operation for conflict resolution as well as for recovering the flight path to the original flight leg. Simulation results for open loop and closed loop operation are presented to validate the approach. Topics requiring further studies are highlighted.

The Influence of Narrowband Interference on DME System Operation

Within the new air traffic management concept, using the Global Navigation Satellite System (GNSS), it is assumed that distance measurement equipment (DME) will be retained. The results of research carried out by several authors have confirmed that global navigation satellite systems (GNSS) can be put out of operation in cases of interference. Therefore, it is very timely to investigate the accuracy and resistance to interference of DME systems. The presented work contains the results of research in the field of assessment of the accuracy and resistance of a DME system, which works in conditions of narrowband interference, using modeling and simulation. Based on the derived model of the DME measurement signal, its parameters, and narrowband interference, algorithms for processing the measurement signals of a DME system in conditions of narrowband interference were derived. A quasi-optimal nonlinear filtering method was used in the derivation of the measurement signal-processing algorithms. A quadratic loss function was used as an optimality criterion, which allows us to obtain the results of measuring the parameters of the DME measurement signal as a minimum of the a posteriori mean error. Within this method, Gaussian approximation and large and small parameter methods were used. Simulation of the operation of the DME system confirmed that the measurement accuracy of this system depends on the stability of the frequency of the DME support generator, and also depends on the signal-to-noise ratio and the signal-to-interference ratio of the DME receiver input. Comparing the results of the DME system receiver designed by us with the parameters listed in in published works that discuss the accuracy of this system, we can conclude that its accuracy is much better. The simulation results confirmed that the potential accuracy of the distance measurement is equal to 2.2 m. However, the mentioned algorithms require substantial simplification to be used for real-time signal processing. This will be our next research direction.

Live Trials of Dynamic Geo-Fencing for the Tactical Avoidance of Hazard Areas

The project City-ATM, launched by the German Aerospace Center DLR in 2018, aims to integrate new airspace users like unmanned aerial vehicles into uncontrolled airspace. An air traffic management and traffic flow control concept were developed. The phase 1 demonstration in 2019 showed a bridge inspection featuring, amongst other elements, the flight of several drones in a limited area, beyond visual line of sight operation, strategic flight planning considering strategic geo-fences and tactical conflict detection. To enrich the base concept from phase 1 with more U-Space services, the concept has been extended for phase 2 by dynamic geo-fencing for the tactical avoidance of danger spots. This paper describes how dynamic geo-fences can be modeled around a hazard area, how the dynamic opening and closure of these fences can be distributed to relevant systems, and how the fences are considered by on-ground and already in air vehicles. The complete concept has been implemented and tested at the National Experimental Test Center in Cochstedt. Finally, the execution of successful flight trials is described.

Wind-optimal lateral trajectories for a multirotor aircraft in urban air mobility

The primary motivation for this paper is to quantify the operational benefits (energy consumption and flight duration) of flying wind-optimal lateral trajectories for short flights (less than 60 miles) anticipated in the urban environment. The optimal control model presented includes a wind model for quantifying the effect of wind on the lateral trajectory. The optimal control problem is numerically solved using the direct collocation method. Energy consumption and flight duration flying wind-optimal lateral trajectories are compared with corresponding values obtained flying great-circle paths between the same origin and destination pairs to determine the operational benefits of wind-optimal routing for short flights. The flight duration results for different scenarios are validated using a simulation tool designed and developed at NASA for exploring advanced air traffic management concepts. This research study suggests that for short flights in an urban environment, operational benefits of the wind-optimal lateral trajectories over the corresponding great-circle trajectories in terms of energy consumption and flight duration per flight are dependent on: i) wind field’s spatial variability, ii) wind magnitude, iii) the direction of route relative to the wind field, and iv) cruise segment length. The operational benefits observed in realistic flyable wind scenarios are less than 2.5%; these could be translated to an equivalent of a maximum of 2 min of cruise flight duration savings in the urban air mobility environment. As expected, headwinds and tailwinds along the flight route most significantly impact energy consumption and flight duration.

Equitable optimized airspace sectorization based on constraint programming and OWA aggregation

PurposeAirspace sectorization is an important task, which has a significant impact in the everyday work of air control services. Especially in recent years, because of the constant increase in air traffic, existing airspace sectorization techniques have difficulties to tackle the large air traffic volumes, creating imbalanced sectors and uneven workload distribution among sectors. The purpose of this paper is to propose a new approach to find optimal airspace sectorization balancing the traffic controller workload between sectors, subject to airspace requirements.Design/methodology/approachA constraint programming (CP) model called equitable airspace sectorization problem (EQASP) relies on ordered weighted averaging (OWA) multiagent optimization and the parallel portfolio architecture has been developed, which integrates the equity into an existing CP approach (Trandac et al., 2005). The EQASP was evaluated and compared with the method of Trandac et al. (2005), according to the quality of workload balancing between sectors and the resolution performance. The comparison was achieved using real air traffic low-altitude network data sets of French airspace for five flight information regions for 24 h a day and the Algerian airspace for three various periods (off peak hours, peak hours and 24 h).FindingsIt has been demonstrated that the proposed EQASP model, which is based on OWA multicriteria optimization method, significantly improved both the solving performance and the workload equity between sectors, while offering strong theoretical properties of the balancing requirement. Interestingly, when solving hard instances, our parallel sectorization tool can provide, at any time, a workable solution, which satisfies all geometric constraints of sectorization.Practical implicationsThis study can be used to design well-balanced air sectors in terms of workload between control units in the strategic phase. To fulfil the airspace users’ constraints, one can refer to this study to assess the capacity of each air sector (especially the overloaded sectors) and then adjust the sector’s shape to respond to the dynamic changes in traffic patterns.Social implicationsThis theoretical and practical approach enables the development and support of the definition of the “Air traffic management (ATM) Concept Target” through improvements in human factors specifically (balancing workload across sectors), which contributes to raising the level of capacity, safety and efficiency (SESAR Vision of ATM 2035).Originality/valueIn their approach, the authors proposed an OWA-based multiagent optimization model, ensuring the search for the best equitable solution, without requiring user-defined balancing constraints, which enforce each sector to have a workload between two user-defined bounds (Wmin, Wmax).

Geometric Approach Towards Airspace Assessment for Emerging Operations

Emerging urban air mobility operators propose to introduce extensive flight networks into metropolitan airspace. However, this airspace currently contains complex legacy airspace structure and flight operations that are perceived as safe, efficient, and generally acceptable to the overflown public. Hence, air traffic management concepts to support these emerging operators may be constrained to cause little to no interference with legacy operations. The identification of airspace that is noninterfering and potentially “available” to these new operators is therefore a critical first step toward their integration. This paper introduces a geometric airspace assessment approach that considers seven features of airspace that may preclude these new operations (that is, airspace constructs). Four hypothetical air traffic management scenarios are developed that prescribe different degrees of integration. An alpha-shape topological method is refined to process geometrically complex airspace construct polygons over an expansive geographic area and develop three-dimensional mappings of airspace availability. The approach is demonstrated in the San Francisco Bay Area and is readily extensible to other locations. It is envisioned to be useful in identification of viable takeoff and landing sites; evaluation of the sensitivity of airspace availability to separation or trajectory conformance requirements; and flight route design, throughput estimation, and risk analysis.

Rotorcraft in the Performance Based Navigation International Civil Aviation Organization Implementation

Abstract European Commision adopted in July new regulations about laying down airspace usage requirements and operating procedures concerning performance based navigation. It is next step in realization of the the global program PBN ICAO. At the 36th General Assembly of ICAO held in 2007, the Republic of Poland agreed to ICAO resolution A36-23 which urges all States to implement PBN. In future aviation concepts the use of Performance Based Navigation (PBN) is considered to be a major Air Traffic Management (ATM) concept element. ICAO has drafted standards and implementation guidance for PBN in the ICAO Doc 9613 “PBN Manual”. The Based Performance Navigation Concept represents and shift from sensor-based to performance based navigation connected with criteria for navigation: accuracy, integrity, availability, continuity and functionality depending on the phase of the flight. Through PBN and changes in the communication, surveillance and ATM domain, many advanced navigation applications are possible to improve airspace efficiency, improve airport sustainability, reduce the environmental impact of air transport in terms of noise and emission, increase safety and improve flight efficiency.

Applying Cognitive Engineering Principles to Allocation of Roles and Responsibilities for a Future Air Traffic Management Concept

NASA’s Management by Trajectory (MBT) concept will improve trajectory predictability by providing methods to keep aircraft on negotiated trajectories; however, the concept impacts roles and responsibilities. Most notably, MBT envisions a different distribution of responsibilities between the Radar-side and Data-side (herein called the negotiating) controllers. Cognitive engineering provides a rich history of research into understanding the roles that humans and automation play in complex systems and some principles for system design. This paper briefly summarizes this literature, focusing on principles underlying the proposed allocation of responsibilities in MBT and the source of automation and information requirements.

A Novel Performance Framework and Methodology to Analyze the Impact of 4D Trajectory Based Operations in the Future Air Traffic Management System

The introduction of new Air Traffic Management (ATM) concepts such as Trajectory Based Operations (TBO) may produce a significant impact in all performance areas, that is, safety, capacity, flight efficiency, and others. The performance framework in use today has been tailored to the operational needs of the current ATM system and must evolve to fulfill the new needs and challenges brought by the TBO content. This paper presents a novel performance assessment framework and methodology adapted to the TBO concept. This framework can assess the key performance areas (KPAs) of safety, capacity, and flight efficiency; equity and fairness are also considered in this research, in line with recent ATM trends. A case study is presented to show the applicability of the framework and to illustrate how some of the complex interdependencies among KPAs can be captured with the proposed approach. This case study explores the TBO concept of “strategic 4D trajectory deconfliction,” where the early separation tasks of 4D trajectories at multisector level are assessed. The framework presented in this paper could potentially support the target-setting and performance requirements identification that should be fulfilled in the future ATM system to ensure determined levels of performance.

Human-in-the-Loop Simulation Analysis of Integrated RPAS Operations in Trajectory Based Operations Environment

In this paper, Human-in-the-Loop (HiTL) simulations of Remotely Piloted Aircraft System (RPAS) operations in two different Air Traffic Management (ATM) concepts, conventional radar vectoring and Trajectory Based Operations (TBO), were performed to assess the impacts of RPAS integration in the future ATM environment. TBO concept maximizes the throughput by planning and sharing 4-D trajectories between pilots and controllers, and it is considered one of the key concepts to enable RPASs to operate with manned aircraft in congested airspaces. RPASs are characterized by having communication delay or temporary loss of communication. TBO capability was added to the integrated air traffic simulation system for this study, which was developed in the Inha University. HiTL simulations were performed by a trainee air traffic controller with three scenarios, and the data were analyzed using safety, efficiency, and controller workload metrics. The results suggest that TBO were effective in reducing delays and controller workload while maintaining the level of safety.

Extending Required Navigation Performance to Include Time Based Operations and the Vertical Dimension

Extending Required Navigation Performance to Include Time Based Operations and the Vertical Dimension

Air traffic generation for new terminal area air traffic management concepts design and evaluation

This paper describes two systems that can be used to obtain realistic random traffic samples in a terminal area: a real traffic analyser and a synthetic traffic generator. These two systems allow the air traffic management (ATM) engineer to gain insight on the traffic structure of the area under analysis, and allow obtaining realistic traffic samples enabling the evaluation of new operational concepts, the validation or system performance measurement after procedure changes, the analysis of ATM performance under forecasted future traffic changes, etc. Together with the design of the system, the work provides insight of user interfaces and describes the potential uses of such tools in an integrated ATM system.

SECTOR COMPLEXITY MEASURES: A COMPARISON

In developing a more advanced human-machine systems for future Air Traffic Management (ATM) concepts requires a deep understanding of what constitutes operator workload and how taskload and sector complexity can affect it. Many efforts have been done in the past to measure and/or predict operator workload using sector complexity. However, most sector complexity metrics that include sector design are calculated according to a set of rules and subjective weightings, rendering them to be dependent of sector. This research focuses on comparing the Solution Space Diagram (SSD) method with a widely accepted complexity metric: Dynamic Density (DD). In essence, the SSD method used in this research, observed aircraft restrictions and opportunities to resolve traffic conflicts in both the speed and heading dimensions. It is hypothesized that the more area covered on the solution space, that is, the fewer options the controller has to resolve conflicts, the more difficult the task and the higher the workload experienced by the controller. To compare sector complexity measures in terms of their transferability in capturing dynamic complexity across different sectors, a human-in-the-loop experiment using two distinct sectors has been designed and conducted. Based on the experiments, it is revealed that the SSD metric has a higher correlation with the controllers' workload ratings than the number of aircraft and the un-weighted NASA DD metric. Although linear regression analysis improved the correlation between the workload ratings and the weighted DD metric as compared to the SSD metric, the DD metric proved to be more sensitive to changes in sector layout than the SSD metric. This result would indicate that the SSD metric is better able to capture controller workload than the DD metric, when tuning for a specific sector layout is not feasible.

Trajectory prediction for future air traffic management – complex manoeuvres and taxiing

AbstractThe future air traffic management (ATM) concept envisaged by the Single European Sky ATM Research – SESAR – and the USA equivalent NextGen, mark a paradigm shift from the current reactive approach of ATM towards holistic strategic collaborative decision making. The core of the future ATM concept relies on common situational awareness over potentially large time-horizons, based upon the user operational intent. This is beyond human capabilities and requires the support of automation tools to predict aircraft state throughout the operation and provide support to optimal decision making long before any potential conflict may arise. This is achieved with trajectory predictors and conflict detectors and resolvers respectively. Numerous tools have been developed, typically geared towards addressing specific airborne applications. However, a comprehensive literature search suggests that none of the tools was designed to predict trajectories throughout the entire operation of an aircraft, i.e. gate-to-gate. Yet, such functionality is relevant in the holistic optimisation of aircraft operations. To address this gap, this paper builds on an existing en route trajectory prediction (TP) model and develops novel techniques to predict aircraft trajectories for the transitions between the ground- and enroute-phases of operation and for the ground-phase, thereby enabling gate-to-gate (or enroute -to-enroute) TP. The model is developed on the basis of Newtonian physics and operational procedures. Real recorded data obtained from a flight data record (FDR) were used to estimate some of the input parameters required by the model. The remaining parameters were taken from the BADA 3.7 model. Performance results using these flight data demonstrate that the proposed TP model has the potential to accurately predict gate-to-gate trajectories and to support future ATM applications such as gate-to-gate synchronisation.

Will Cost-Effectiveness Decisions Determine Future 4D Air Traffic Management Concepts?

Would an increased emphasis on cost-effectiveness and markedly reduced controller workload/costs determine the Four-Dimensional Air Traffic Management (4D ATM) Concept – a mindset change? Are there workable concepts that focus on flightpath conformance monitoring rather than a combination of conformance and hazard monitoring? Fundamental criteria for a conformance management-based system are identified to meet workload and cost goals. A ‘Global Navigation Satellite System (GNSS)/Feedback Concept’ is sketched, with radical ingredients to convert GNSS's accurate position fixes into accurate aircraft flightpath navigation. This eliminates air/ground trajectory synchronisation processing, and focuses conflict probing/planning tools on non-conforming flights. This concept would need to address key Human Factor concerns satisfactorily.

New Concept for Wake-Vortex Hazard Mitigation Using Onboard Measurement Equipment

Wake-vortex hazards are a huge threat in aviation. These hazards are well accepted in the vicinity of airports (both departure and arrival). But also a number of en route incidents have happened in the past. Current wake-vortex mitigation strategies are based on static distances (in space and/or time). In future air traffic management concepts of Single European Sky Air Traffic Management Research and NextGen, these static distances will be replaced by dynamic separation strategies. Furthermore, concepts for self-separation of aircraft are described. This paper will discuss the work at Technische Universität Braunschweig, where a new concept for wake-vortex hazard mitigation has been developed. The basic idea of the new concept is that only a criticality parameter will be transmitted between aircraft to ensure a safe separation even within new self-separation concepts. The criticality parameter will give an indication about the severity (and therefore criticality to the following aircraft) of the vortices. Additionally, Technische Universität Braunschweig will install wind-turbulence measurement equipment onboard its research aircraft. This installation will be also be described, and the possible usage will be discussed.

A 4D ATM Trajectory Concept Integrating GNSS and FMS?

NextGen and SESAR have now been under development for several years, but have increasingly complex engineering and operational specifications. A variant Air Traffic Management (ATM) concept is sketched for generating fuel-efficient, very accurate and air-ground synchronized 4D-trajectories by using flight segment groundspeed profiles and linking Global Navigation Satellite Systems (GNSS) data to the aircraft Flight Management Systems (FMS) with feedback control. Is this a flawed concept or a feasible and operationally practical proposition?

Cruise speed reduction for ground delay programs: A case study for San Francisco International Airport arrivals

Ground Delay Programs (GDP) are sometimes cancelled before their initial planned duration and for this reason aircraft are delayed when it is no longer needed. Recovering this delay usually leads to extra fuel consumption, since the aircraft will typically depart after having absorbed on ground their assigned delay and, therefore, they will need to cruise at more fuel consuming speeds. Past research has proposed speed reduction strategy aiming at splitting the GDP-assigned delay between ground and airborne delay, while using the same fuel as in nominal conditions. Being airborne earlier, an aircraft can speed up to nominal cruise speed and recover part of the GDP delay without incurring extra fuel consumption if the GDP is cancelled earlier than planned. In this paper, all GDP initiatives that occurred in San Francisco International Airport during 2006 are studied and characterised by a K-means algorithm into three different clusters. The centroids for these three clusters have been used to simulate three different GDPs at the airport by using a realistic set of inbound traffic and the Future Air Traffic Management Concepts Evaluation Tool (FACET). The amount of delay that can be recovered using this cruise speed reduction technique, as a function of the GDP cancellation time, has been computed and compared with the delay recovered with the current concept of operations. Simulations have been conducted in calm wind situation and without considering a radius of exemption. Results indicate that when aircraft depart early and fly at the slower speed they can recover additional delays, compared to current operations where all delays are absorbed prior to take-off, in the event the GDP cancels early. There is a variability of extra delay recovered, being more significant, in relative terms, for those GDPs with a relatively low amount of demand exceeding the airport capacity.

System Wide Information Management Architecture Designing

As an important technical support platform of the next generation air traffic management concepts, Civil Aviation Wide Information Management System is responsible for providing various types of interactive information to relative business departments. This paper took SOA approach to analyze and design the function architecture of SWIM. And focused on the different technical approaches and deploying integration levels, it analyzed two kinds of SWIM technical architecture selections. This paper is funded by the National Science and Technology Supporting Program Civil Aviation Wide Information Management Technology and Platform (No. 2011BAH24B07) Project.