This paper addresses the challenge of designing provably safe conflict-resolution procedures (CRPs) that are decentralized and decoupled from each other. The main contribution of this paper is identifying necessary and sufficient conditions to decouple CRPs. Additionally, this paper demonstrates the existence of decentralized en-route CRPs that satisfy the identified decoupling conditions for each local conflict and, thereby, guarantee global conflict resolution. An advantage of the proposed CRPs is that they do not require a reduction in the aircraft flow levels in the intersecting routes for conflict resolution, which can aid in increasing the efficiency of en-route air traffic control.

Decoupled Conflict-Resolution Procedures for Decentralized Air Traffic Control

Air traffic in the North Atlantic oceanic airspace (NAT) experiences very strong winds caused by jet streams. Flying wind-optimal trajectories increases individual flight efficiency, which is advantageous when operating in the NAT. However, as the NAT is highly congested during peak hours, a large number of potential conflicts between flights are detected for the sets of wind-optimal trajectories. Conflict resolution performed at the strategic level of flight planning can significantly reduce the airspace congestion. However, being completed far in advance, strategic planning can only use predicted environmental conditions that may significantly differ from the real conditions experienced further by aircraft. The forecast uncertainties result in uncertainties in conflict prediction, and thus, conflict resolution becomes less efficient. This work considers wind uncertainties in order to improve the robustness of conflict resolution in the NAT. First, the influence of wind uncertainties on conflict prediction is investigated. Then, conflict resolution methods accounting for wind uncertainties are proposed.

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Conflict resolution for wind-optimal aircraft trajectories in North Atlantic oceanic airspace with wind uncertainties

This paper provides an overview of problem resolution capabilities being developed to assist en route air traffic controllers. This function is termed Problem Analysis, Resolution and Ranking (PARR). PARR is envisioned as an enhancement to the User Request Evaluation Tool (URET) Free Flight Phase 1 (FFP1) capability, and has been designated as Priority Research for the follow-on Free Flight Phase 2 (FFP2) effort. PARR is being developed as a series of incremental enhancements to URET, with the Initial PARR capabilities focusing on providing additional support to the Radar Associate (D) controller for the resolution of aircraft-to-aircraft and aircraft-to-airspace problems. Subsequent PARR enhancements address the avoidance of severe weather areas, the implementation of Traffic Flow Management (TFM) flow initiatives, and the integration into a common en route Sector Team Computer-Human Interface (CHI). This paper provides an overview of the Initial PARR capabilities and a summary of results from ongoing evaluations with active field controllers. An overview of the techniques being developed for the PARR functional performance and benefits assessment is given, along with initial results. Finally, concepts are described for the enhancement of URET and PARR to assist in the avoidance of severe weather areas and implementation of TFM flow initiatives.

http://www.atmseminar.org/seminarContent/seminar4/papers/p_093_DSTCDM.pdf

Problem Analysis, Resolution and Ranking (PARR) Development and Assessment

North Atlantic oceanic airspace accommodates more than 1000 flights daily, and is subjected to very strong winds. Flying wind-optimal trajectories yields time and fuel savings for each individual flight. However, when taken together, these trajectories induce a large amount of potential enroute conflicts. This paper analyses the detected conflicts, figuring out conflict distribution in time and space. It further describes an optimization algorithm aimed at reducing the number of conflicts for a daily set of flights on strategic level. Several trajectory modification strategies are discussed, followed with simulation results. Finally, an algorithm improvement is presented aiming at better preserving the trajectory optimality.

/pdf/deconflicting-wind-optimal-aircraft-trajectories-in-north-44y5rwc2pj.pdf

Deconflicting Wind-Optimal Aircraft Trajectories in North Atlantic Oceanic Airspace

Remote-controlled or autonomous multi-rotor air vehicles, or drones, have become common and commercially available even to individual consumers, mostly for imaging purposes. Drones appeal to mission architects looking to extend the toolbox provided to operators performing challenging missions such as public safety operations. However, careful analysis of the operational context and concept of operations must take place before major acquisitions. The purpose of this paper is to propose a model-based operational architecture definition framework, which is based on the Department of Defense Architecture Framework (DoDAF) ontology and uses Object Process Methodology (OPM) as its underlying modeling language. Through careful mapping of DoDAF Operational Viewpoint (OV) ontology to OPM ontology, we were able to show that the entire OV ontology can be covered by a small set of objects, processes, relations among them, and constructs comprising them. We then show how to instantiate the ontology to create a model of an actual architecture of interest (AoI) while maintaining strong typing of the model elements to ensure validity, integrity, consistency, and continuous compliance with the OV. We demonstrate our approach on the case of using drones in public safety enterprises for the purpose of crowd management in massively attended events and locations. The proposed framework allows for capturing ConOps and OpsCon in a lightweight, yet robust and consistent manner, and improve communication and concept validation between operational stakeholders and enterprise architects.

Object-Process Model-Based Operational Viewpoint Specification for Aerospace Architectures

In an effort to accommodate the predicted growth in air traffic, the Federal Aviation Administration (FAA) and the aviation community have developed a concept of operations for the National Airspace System (NAS) called Free Flight. This operational concept has been developed for the midterm time frame (nominally a period of time that centers around 2005). The Center for Advanced Aviation System Development (CAASD) at The MITRE Corporation developed the concept and has conducted laboratory exercises to validate the portion of the concept that applies to the en route domain. The paper describes CAASD's laboratory efforts to begin validating the en route portion of the concept by examining the operational issues associated with the concept and the functional issues related to its evolution to the midterm. The laboratory validation exercises described examine the functionality of possible capability enhancements, but do not address associated detailed human factors issues. Favorable results from CAASD's initial qualitative validation efforts support the need for further quantitative validation activities that include more detailed analyses, further development of operational procedures and computer-human interfaces, and more rigorous exercises involving FAA field controllers.

C.G. Ball

Papers

Validating a future operational concept for en route air traffic control