Probabilistic Strategic Conflict-Management for 4D Trajectories in Free-Route Airspace

Abstract

The expected growth of air traffic in the following decades demands the implementation of new operational concepts to avoid current limitations of the air traffic management system. This paper focuses on the strategic conflict management for four-dimensional trajectories (4DT) in free-route airspace. 4DT has been proposed as the future operational concept to manage air traffic. Thus, aircraft must fulfil temporary restrictions at specific waypoints in the airspace based on time windows. Based on the temporary restrictions, a strategic conflict management method is proposed to calculate the conflict probability of an aircraft pair (that intersects in the air) and to calculate temporary-blocking windows that quantify the time span at which an aircraft cannot depart because one conflict could occur. This methodology was applied in a case-study for an aircraft pair, including the uncertainty associated with 4DT. Moreover, a sensitivity analysis was performed to characterise the impact of wind conditions and speed control on the temporary-blocking windows. The results concluded that it is feasible to propose 4DT strategic de-confliction based on temporary-blocking windows. Although, uncertainty variables such as wind and speed control impact on the conflict probability and the size of the temporary-blocking windows.

On Probabilistic Risk of Aircraft Collision along Air Corridors

“…The fundamental problem addressed in this paper of ensuring extremely low collision probabilities has implications for conflict resolution measures [55,56], which apply both to manned and unmanned aircraft if operating in non-segregated airspace [57][58][59], as an alternative to geofencing [60]. Conflict resolution may be automated [61] if reliable trajectory information is available [62], which is not always the case, for example for aircraft collision with birds [63].…”

“…All the steps from the choice of the probability distribution for large flight path deviations up to the final metrics for collision risk have been documented in some detail, because they apply to any encounter geometry, not only flight along air corridors, but also to level crossings [55] and climbing and descending flights [53]. A complete flight plan can often be described by straight paths between waypoints and curved trajectories approximated by straight segments.…”

Design of an ATC Tool for Conflict Detection Based on Machine Learning Techniques

“…Other approaches perform simulations adding uncertainty to different operational variables (wind, weight, velocity, etc.) [29][30][31][32]. The goal is to obtain an extensive database with enough separation infringements, which is not trivial.…”

The omnidirectional runway with infinite heading as a futuristic runway concept for future free route airspace operations

“…At the end of 2030, it is expected that all Area Control Centers (ACCs) in Europe will have fully implemented the FRA concept (EUROCONTROL, 2021a(EUROCONTROL, , 2021b. A number of studies have been carried out on the implementation of FRA (Nava Gaxiola and Barrado, 2016;Gaxiola et al, 2018;Vagner and Ferencov a, 2018;Pérez-Cast an et al, 2020). Gaxiola et al (2018) and Pejovic et al (2019) studied the deployment of FRA in the Northern European FRA in terms of safety concerns.…”