Scheduling aircraft landings - the static case

This is the publisher version of the article, obtained from the link below.In this paper, we consider the problem of scheduling aircraft (plane) landings at an airport. This problem is one of deciding a landing time for each plane such that each plane lands within a predetermined time window and that separation criteria between the landing of a plane and the landing of all successive planes are respected. We present a mixed-integer zero–one formulation of the problem for the single runway case and extend it to the multiple runway case. We strengthen the linear programming relaxations of these formulations by introducing additional constraints. Throughout, we discuss how our formulations can be used to model a number of issues (choice of objective function, precedence restrictions, restricting the number of landings in a given time period, runway workload balancing) commonly encountered in practice. The problem is solved optimally using linear programming-based tree search. We also present an effective heuristic algorithm for the problem. Computational results for both the heuristic and the optimal algorithm are presented for a number of test problems involving up to 50 planes and four runways.J.E.Beasley. would like to acknowledge the financial support of the Commonwealth Scientific and Industrial Research Organization, Australia

Low-complexity algorithms for sequencing jobs with a fixed number of job-classes

In this paper we consider the problem of scheduling n jobs such that makespan is minimized. It is assumed that the jobs can be divided into K job-classes and that the change-over time between two consecutive jobs depends on the job-classes to which the two jobs belong. In this setting, we discuss the one machine scheduling problem with arbitrary processing times and the parallel machines scheduling problem with identical processing times. In both cases it is assumed that the number of job-classes K is fixed. By using an appropriate integer programming formulation with a fixed number of variables and constraints, it is shown that these two problems are solvable in polynomial time. For the one machine scheduling case it is shown that the complexity of our algorithm is linear in the number of jobs n. Moreover, if the problem is encoded according to the high multiplicity model of Hochbaum and Shamir, the time complexity of the algorithm is shown to be a polynomial in log n. In the parallel machine scheduling case, it is shown that if the number of machines is fixed the same results hold. Copyrigh

An Optimistic Planning Approach for the Aircraft Landing Problem

International audienceThe Aircraft Landing Problem consists in sequencing aircraft on the available runways and scheduling their landing times taking into consideration several operational constraints, in order to increase the runway capacity and/or to reduce delays.In this work we propose a new Mixed Integer Programming (MIP) model for sequencing and scheduling aircraft landings on a single or multiple independent runways incorporating safety constraints by means of separation between aircraft at runways threshold. Due to the NP-hardness of the problem, solving directly the MIP model for large realistic instances yields redhibitory computation times. Therefore, we introduce a novel heuristic search methodology based on Optimistic Planning that significantly improve the FCFS (First-Come First-Served) solution, and provides good-quality solutions inreasonable computational time. The solution approach is then tested on medium and large realistic instances generated from real-world traffic on Paris-Orly airport to show the benefit of our approach

Fuel-efficient trajectories traffic synchronization

Continuous descent operations (CDOs) with required times of arrival (RTA) have been identified as a potential solution for reducing the environmental footprint of aviation in the terminal maneuvering area without compromising capacity. This paper assesses the feasibility of replacing current air traffic control sequencing and merging techniques, mainly based on path stretching and air holding, by a control based on RTA over metering fixes on known and fixed arrival routes. Because the remaining distance to the runway threshold is always known by the aircraft crew, this would allow engine-idle CDOs that do not require speed-brake usage and where only elevator control is used to meet the RTA. The assessment has been performed for Barcelona-El Prat Airport (Spain) using historical traffic demand data. The earliest and latest trajectories at a metering fix for each inbound aircraft were computed assuming engine-idle CDOs. Given the attainable RTA window for each aircraft, the aircraft sequencing problem was solved. The results show that assigning RTA allows optimizing the landing sequence when air traffic is low. For scenarios with high-traffic loads and late RTA assignments, path stretching still was found to be necessary. The minimum distance from the runway where inbound aircraft should receive the RTA to fully remove any radar vectoring was also analyzed. It was demonstrated that the assignment of RTA well before starting the descent would favor to enable full CDOs.Peer ReviewedPostprint (published version

A dynamic programming approach for the aircraft landing problem with aircraft classes

The capacity of a runway system represents a bottleneck at many international airports. The current practice at airports is to land approaching aircraft on a first-come, first-served basis. An active rescheduling of aircraft landing times increases runway capacity or reduces delays. The problem of finding an optimal schedule for aircraft landings is referred to as the “aircraft landing problem”. The objective is to minimize the total delay of aircraft landings or the respective cost. The necessary separation time between two operations must be met. Due to the complexity of this scheduling problem, recent research has been focused on developing heuristic solution approaches. This article presents a new algorithm that is able to create optimal landing schedules on multiple independent runways. Our numerical experiments show that problems with up to 100 aircraft can be optimally solved within seconds instead of hours that are needed to solve these problems with standard optimization tools

管制運用に向けた航空交通流過密状態における進化計算に基づく着陸順最適化

電気通信大学201

No more conflicts: the development of a generic airport model in a sequence-optimization framework

International audienceComponents of the airport airside such as runways, taxiways and aprons, have a significant impact in the total capacity of the airport system, where capacity is usually considered as maximum number of air traffic movements or number of passengers accommodated in a given period of time. Operations on the airside impact in the propagation of delay and consequently in the perceived level of service by passengers the terminal buildings. This paper put the focus on the airside operations at airports. A methodology for modelling operations on the ground and the successive optimization is proposed. The methodology presented in this paper is generic enough in the sense that it can be applied to any airport. The objective of this work is to come up with a generic tool that can be used by air traffic controllers in order to minimize conflicts on the ground and consequently increase the airport capacit

Implementation of an Optimization and Simulation-Based Approach for Detecting and Resolving Conflicts at Airport

International audienceIn this paper is presented a methodology that uses simulation together with optimization techniques for a conflict detection and resolution at airports. This approach provides more robust solutions to operative problems, since, optimization allows to come up with optimal or suboptimal solutions, on the other hand, simulation allows to take into account other aspects as stochasticity and interactions inside the system. Both the airport airspace (terminal manoeuvring area), and airside (runway taxiways and terminals), were modelled. In this framework, different restrictions such as speed, separation minima between aircraft, and capacity of airside components were taken into account. The airspace was modeled as a network of links and nodes representing the different routes, while the airside was modeled in a low detail, where runway, taxiways and terminals were modeled as servers with a specific capacity. The objective of this work is to detect and resolve conflicts both in the airspace and in the airside and have a balanced traffic load on the ground

Merging Flows in Terminal Moneuvering Area using Time Decomposition Approach

International audienceWith a continuous growth of air traffic demand, more effort must be made to alleviate the current overloaded airspace charges. This research focuses on the aircraft merging and sequencing problem at Terminal Maneuvering Area. Tactical conflict detection and resolution methods are applied to a predefined route network structure. Speed and time changes are proposed via an optimization methodology to resolve conflicts and maintain separation between aircraft with regard to the wake turbulence constraints and runway occupancy time. A new time decomposition approach is introduced. It consists in partitioning the whole time interval under consideration into several overlapping time windows, and in solving the merging and sequencing problem individually in each such sub-window. Four aircraft status are defined to classify flights according to their temporal position relative to the current sliding window. Moreover, an adapted simulated annealing heuristic is proposed to solve the corresponding sub-problems. Finally, computational experiments of the proposed algorithm, performed on real-world case studies of Paris Charles De-Gaulle airport, show the benefits of this sliding-window time-decomposition approac