Francisco Javier Sáez Nieto

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Verified

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• PhD
• Professor (retired) at Universidad Politécnica de Madrid

This chapter describes a collision risk model (CRM) of airspace scenarios to analyse their safety levels when populated by given air traffic. The model requires the use of representative data, containing a description of the flown aircraft trajectories. It is a combination of deterministic and probabilistic mathematical tools able to estimate the l...

This paper proposes a methodology to characterize and evaluate the performance of the aircraft operation in complex systemized terminal manoeuvring area based on the study of its standard routes structure and their actual traffic. The methodology is composed of two main components. The first component identifies recurrent patterns by calculating th...

Heinrich’s pyramid theory is one of the most influential theories in accident and incident prevention, especially for industries with high safety requirements. Originally, this theory established a quantitative correlation between major injury accidents, minor injury accidents and no-injury accidents. Nowadays, researchers from different fields of...

Air Traffic Management is evolving towards a Trajectory-Based Operations paradigm. Trajectory prediction will hold a key role supporting its deployment, but it is limited by a lack of understanding of air traffic associated uncertainties, specifically contextual factors. Trajectory predictors are usually based on modelling aircraft dynamics based o...

System Safety Assessment is an integral part of the design and operation of aviation and Air Traffic Management (ATM) systems. The aim of the System Safety Assessment is to identify, quantify and mitigate any and all risks; and to ensure that the system complies with the safety levels established by the regulatory authority. This paper presents an...

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, th...

The occurrence of Losses Of Separation between aircraft in an airspace that could lead to Mid Air Collisions (MAC) is of major concern to Air Traffic Management. This paper uses an innovative approach to develop Safety Performance Functions to predict the occurrence of losses of separation. This will improve the safety conditions under which airlin...

This paper combines Bayesian networks (BN) and information theory to model the likelihood of severe loss of separation (LOS) near accidents, which are considered mid-air collision (MAC) precursors. BN is used to analyze LOS contributing factors and the multi-dependent relationship of causal factors, while Information Theory is used to identify the...

The Air Traffic Management system is under a paradigm shift led by NextGen and SESAR. The new trajectory-based Concept of Operations is supported by performance-based trajectory predictors as major enablers. Currently, the performance of ground-based trajectory predictors is affected by diverse factors such as weather, lack of integration of operat...

Currently, a maximum allowable number of aircraft (A/C) entering and or within a sector for a given period is fixed. Anytime this threshold is reached, involved A/C are regulated by Air Traffic Flow and Capacity Management (ATFCM) to maintain an acceptable Air Traffic Controllers’ (ATCOs’) workload. This threshold is determined regardless of partic...

To support future automated transitions among the ATM safety nets, this study elaborates identification of the complex traffic scenarios based on the concept of aerial ecosystems. As an extension of the TCAS operational domain and evolving from the separation management towards collision avoidance layer, the concept has been developed as a stepwise...

Present research on Air Traffic Management (ATM) is tending to improve airspace capacity, accessibility and the efficiency of operations in high-density areas, while maintaining or improving the safety performance indicators. Tactical interventions from the Air Traffic Control (ATC) system to preserve safety distances between aircraft have some inh...

Transition between Separation Management in ATM and Collision Avoidance constitutes a source of potential risks due to non-coherent detection and resolution clearances between them. To explore an operational integration between these two safety nets, a complexity metric tailored for both Separation Management and Collision Avoidance, based on the i...

In the future air traffic management system, the trajectory becomes the fundamental element of a new set of operating procedures collectively referred to as trajectory-based operations. Trajectory-based operations require the air traffic management to introduce profound innovations to enable the envisioned changes. Some of these include collaborati...

The main objective of this paper is to present our vision of the role of automation in future air traffic management (ATM) system. It also includes an analysis and state of the art on ATM and automation. The content is based on HALA! position paper, that looks beyond the framework defined by SESAR and NextGen for the near future, and analyses the f...

A study that examines the use of aircraft as wind sensors in a terminal area for real-time wind estimation in order to improve aircraft trajectory prediction is presented in this paper. We describe not only different sources in the aircraft systems that provide the variables needed to derivate the wind velocity but the capabilities which allow us t...

This paper presents a method to segment airplane radar tracks in high density terminal areas where the air traffic follows trajectories with several changes in heading, speed and altitude. The radar tracks are modelled with different types of segments, straight lines, cubic spline function and shape preserving cubic function. The longitudinal, late...

Aligned with SESAR objectives of Traffic Synchronisation and 4D Trajectory Management, this paper presents different approaches to optimised algorithms in AMAN's, taking into account various innovative criteria. Analysing KPI's commonly used in TMA's, the different algorithms are tested in order to detect the strengths and weakness of each algorith...

This paper presents a comparison between the most relevant on-going activities in the creation and implementation of the Arrival Traffic Synchronisation Concept of Operations worldwide, by analysing and breaking down the requirements and approaches underlying the problem of 'tactical establishment and maintenance of a safe, orderly and efficient fl...

Airliners and Remotely Piloted Aircraft Systems (RPAS), with very different performances and features, will have to coexist in a seamless airspace whose definition and technological infrastructure, the Single European Sky ATM Research initiative (SESAR), is currently undertaking. This paper presents the Concept of Operations (CONOPS) of the integra...

The current lack of efficiency in the use of airspace, enforced by the economic crisis an the increasing competitiveness among air transport companies are drivers for a renewed interest for the application of optimization techniques to find answers to overcame current inefficiencies. The main objective of the present paper is to assess and compare...

Aircraft Operators Companies (AOCs) are always willing to keep the cost of a flight as low as possible. These costs could be modelled using a function of the fuel consumption, time of flight and fixed cost (over flight cost, maintenance, etc.). These are strongly dependant on the atmospheric conditions, the presence of winds and the aircraft perfor...

The goal of the paradigm shift in Air Traffic Management (ATM) is to increase its overall performance by means of redesigning processes, evolving to a more automated, autonomous and predictable system. Nevertheless, when dealing with automation, it is important to determine until what extent can any part of the system or process be automated, that...

Knowledge of the characteristics of the atmosphere will benefit future air traffic management systems, particularly the so-called ‘four-dimensional trajectory management’. Trajectory prediction should incorporate variables such as air pressure (p), wind velocity (w) and temperature (T), as well as clouds/visibility, gusts/microbursts and the concen...

The use of barometric altimetry is to some extent a limiting factor on safety, predictability and efficiency of aircraft operations, and reduces the potential of the trajectory based operations capabilities. However, geometric altimetry could be used to improve all of these aspects. Nowadays aircraft altitude is estimated by applying the Internatio...

Today's motivation for autonomous systems research stems out of the fact that networked environments have reached a level of complexity and heterogeneity that make their control and management by solely human administrators more and more difficult. The optimisation of performance metrics for the air traffic management system, like in other networke...

In the context of civil air navigation, and following the proposed paradigm shift for Air Traffic Management (ATM), it has become necessary to be able to improve accuracy of Trajectory Predictors (TP). This is particularly relevant for analysis and design of Terminal Manoeuvring Areas procedures, which consist of a mixture of conventional, Continuo...

Challenging to graduate engineering education is extraordinary. Engineering schools must prepare PhD students to work in transnational settings, with scientists and researchers located across the globe, in order to increase the world's capacity for solving global problems and meeting human needs. This paper presents an innovative project, financed...

HALA! (Higher Automation Levels in Air Traffic Management) is a Research Network which was initiated in September 2010, inspired and underpinned by the highest principles of collaboration, transparency and innovation for the effective application of automation of Air Transport processes, that pretends to develop research in high-risk, novel or unco...

HALA! (Higher Automation Levels in Automation) is a SESAR WP-E Research Network inspired and underpinned by the highest principles of collaboration, transparency and innovation for the effective application of automation of the ATM processes. HALA! is ready to support and complement SESAR R&D activities in Automation, providing a Scientific Collabo...

A three-dimensional collision risk model (CRM) is being developed by the Technical University of Madrid and INECO for the European Organization for the Safety of Air Navigation (EUROCONTROL) as a method of assessing the European en-route risk, due to all causes and across all dimensions within the airspace. This model provides a method for assessin...

The need for the use of another surveillance system when radar cannot be used is the reason for the development of the Multilateration (MLT) Systems. However, there are many systems that operate in the L-Band (960-1215MHz) that could produce interference between systems. At airports, some interference has been detected between transmissions of MLT...

A 3D Collision Risk Model (CRM) is being developed by EUROCONTROL as a method of assessing the European en-route risk, due to all causes and across all dimensions within the airspace. This model is expected to be able to provide an estimation of the current risk in a suitable metric, providing measurements of the peak risks in terms of time, geogra...