Browsing by Author "Sáez Nieto, Francisco Javier"

Now showing 1 - 4 of 4
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    A case study of fishbone sequential diagram application and ADREP taxonomy codification in conventional ATM incident investigation
    (MDPI, 2019-04-04) Liang Cheng, Schon Z. Y.; Arnaldo Valdés, Rosa María; Gómez Comendador, Victor Fernando; Sáez Nieto, Francisco Javier
    This paper aims to present the application of a fishbone sequential diagram in air traffic management (ATM) incident investigations performing as a key connection between safety occurrence analysis methodology (SOAM) and accident/incident data reporting (ADREP) approaches. SOAM analysis is focused on organizational cause detection; nevertheless, this detection of individual causes from a complete incident scenario presents a complex analysis, and even more, the chronological relationship between causes, which is lacking in SOAM, should be tracked for post-investigation analysis. The conventional fishbone diagram is useful for failure cause classification; however, we consider that this technique can also show its potential to establish temporal dependencies between causes, which are categorized and registered with ADREP taxonomy for future database creation. A loss of separation incident that occurred in the Edmonton area (Canada) is used as a case study to illustrate this methodology as well as the whole analysis process.
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    Finding precursory air traffic management safety metrics using exploration of trajectory radar tracks
    (American Society of Civil Engineers, 2017-10-23) Barragán Montes, Rocío Barragán; Gómez Comendador, Victor Fernando; Sáez Nieto, Francisco Javier; Pérez Sanz, Luis
    The definition of a set of precursory safety metrics is critical to detect when an airspace is degrading in terms of safety and thus undesired effects are becoming more likely. Furthermore, safety metrics are paramount in the measurement of the impact of new operational procedures or technical improvements in the air traffic control system. The study presented in this paper introduces three safety metrics (reaction time performance indicator, time to closest point of approach performance indicator, and time to closest point of approach critical limit ratio) derived from a given airspace and a sizable, assorted traffic sample extracted from traffic surveillance track data. The metrics are used to characterize the airspace as a function of the safety outcome, which can be continuously overseen. The final goal of the safety metrics is to be used as an airspace safety warning system, where precursory metrics would signal the need to act to maintain the air traffic control system safety target in the face of operational, organizational, technical, or legal changes.
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    A method of ATFCM based on trajectory based operations.
    (2018-09) Gatsinzi, Dany; Sáez Nieto, Francisco Javier; Mandani, Irfan
    This thesis describes a method towards a more proactive approach for Air Traffic Flow and Capacity Management (ATFCM) Demand and Capacity Balancing (DCB). This new ATFCM DCB method focuses on reducing the expected Air Traffic Control (ATC) Separation Management (SM) tactical interventions. It is based on the identification of “hotspots” and mitigating them at pre-flight phase by applying minor adjustments on aircraft’s Times of Arrivals (TOAs) at points of conflict located at en-route crossing and merging junctions (hotspots). The adjustments of TOAs are achieved through optimal speed changes in aircraft speed profiles, applied before and after each junction whilst maintaining each aircraft’s flight time and the entropy of the whole traffic network. The approach postulates that the TOA adjustments may be transformed into a pre-tactical ATFCM DCB measure. This can be achieved by translating TOA adjustments into time constraints at junctions, issued by the Network Manager (NM) in the Reference Business Trajectories (RBTs) to produce de-randomized and well-behaved (conflict free) traffic scenarios to reduce the probability of conflicts. Several real high-density scenarios of the current and forecasted traffic in European Civil Aviation Conference (ECAC) airspace network are simulated using specialized modelling tools to validate the method. A novel Linear Programming (LP) optimisation model is formulated and used to compute optimal speed changes that remove all conflicts in the scenarios with minimum cascading effect. This method should enable a reduction in ATC workload, leading to improvements in airspace capacity, flight and network efficiency as well as safety. This approach is fully aligned to Trajectory Based Operation (TBO) principles. As a holistic solution, this new ATFCM DCB method should change the conventional capacity-limiting factor, currently established by the number of aircraft simultaneously entering each sector (sector count) to another factor where the level of traffic complexity, flying towards junctions is identified and mitigated at pre-flight phase.
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    Probability of potential collision for aircraft encounters in high density airspaces
    (INTECH, 2012-08-01) Arnaldo, R; Sáez Nieto, Francisco Javier; Garcia, E; Portillo, Y
    Failure Management consists of a set of functions that enable the detection, isolation, and correction of anomalous behavior in a monitored system trying to prevent system failures. An effective failure management should monitor the system looking for errors and faults that could end up in a failure and overcome such issues when they arise.