document

A Comparative Study of Optimization Models for Condition-Based Maintenance Scheduling of an Aircraft Fleet

Tseremoglou, I. (author), van Kessel, Paul J. (author), Santos, Bruno F. (author)

Condition-based maintenance (CBM) scheduling of an aircraft fleet in a disruptive environment while considering health prognostics for a set of systems is a very complex combinatorial problem, which is becoming more challenging in light of the uncertainty included in health prognostics. This type of problem falls under the broad category of...

journal article 2023

document

Fleet planning under demand and fuel price uncertainty using actor–critic reinforcement learning

Geursen, Isaak L. (author), Santos, Bruno F. (author), Yorke-Smith, N. (author)

Current state-of-the-art airline planning models face computational limitations, restricting the operational applicability to problems of representative sizes. This is particularly the case when considering the uncertainty necessarily associated with the long-term plan of an aircraft fleet. Considering the growing interest in the application of...

journal article 2023

document

Airline Network Planning Considering Climate Impact: Assessing New Operational Improvements

Noorafza, M. (author), Santos, Bruno F. (author), Sharpanskykh, Alexei (author), Zengerling, Zarah L. (author), Weder, Christian M. (author), Linke, Florian (author), Grewe, V. (author)

The aviation industry has set an ambitious goal of reducing its climate impacts. Accordingly, airlines must balance their plans according to this goal with financial considerations. We developed a multi-objective framework to facilitate climate-aware network design by incorporating the objective to minimise the flight average temperature...

journal article 2023

document

CHAIRS: A choice-based air transport simulator applied to airline competition and revenue management

Fukushi, Mitsuyoshi (author), Delgado, Felipe (author), Raveau, Sebastián (author), Santos, Bruno F. (author)

In Revenue Management (RM) systems, information censoring and the interaction between the forecasting and optimization stages, increases the costs and complexity of performance analysis using historical data. An affordable and suitable alternative is using simulations, but appropriate behavioral models must be considered. In the following...

journal article 2022

document

A combined forecasting and packing model for air cargo loading: A risk-averse framework

Tseremoglou, I. (author), Bombelli, A. (author), Santos, Bruno F. (author)

In this paper, we present a combined forecasting and optimization decision-support tool to assist air cargo revenue management departments in the acceptance/rejection process of incoming cargo bookings. We consider the case of a combination airline and focus on the passenger aircraft belly capacity. The process is dynamic (bookings are received...

journal article 2022

document

The Impact of Prognostic Uncertainty on Condition-Based Maintenance Scheduling: an Integrated Approach

Tseremoglou, I. (author), Bieber, M.T. (author), Verhagen, W.J.C. (author), Santos, Bruno F. (author), Freeman, F.C. (author), van Kessel, P.J. (author)

One of the challenges of Condition-Based Maintenance (CBM) is to combine health monitoring and predictions with efficient scheduling tools. However, the majority of literature is focusing on the assessment of prognostics algorithms performance. In fact, the added value of these algorithms can only be assessed when considering their impact on...

conference paper 2022

document

The Impact of Metrics on the Choice of Prognostic Methodologies

Bieber, M.T. (author), Verhagen, W.J.C. (author), Santos, Bruno F. (author)

Metrics play an important part in the development and application of prognostic methodologies as they provide the capability to characterize and assess the quality of remaining useful life predictions. Although there is a wide range of both, prognostic metrics and prognostic methodologies available, the choice of those often is a demanding and...

conference paper 2022

document

Airline maintenance task rescheduling in a disruptive environment

van Kessel, Paul J. (author), Freeman, Floris C. (author), Santos, Bruno F. (author)

Airline maintenance task scheduling takes place in a disruptive environment. The stochastic arrival of corrective maintenance tasks and changes in both fleet and resource availability require schedules to be continuously adjusted. An optimal schedule ensures that all tasks are executed before their due date in both an efficient (at minimum...

journal article 2022

document

A Data-drive Approach for Robust Cockpit Crew Training Scheduling

van Kempen, J. (author), Santos, Bruno F. (author), Scherp, L. (author)

This work addresses the cockpit crew training scheduling problem. The objective is to produce a robust cockpit crew training schedule, including the assignment of trainees, instructors and simulators. To attain this objective, we propose a scheduling framework composed of four modules: a Training Scheduling & Assignment Model (TS&AM),...

journal article 2022

document

A novel decision support system for optimizing aircraft maintenance check schedule and task allocation

Deng, Q. (author), Santos, Bruno F. (author), Verhagen, W.J.C. (author)

Modern aircraft have thousands of parts, systems, and components that need to be recurrently inspected or replaced. To keep the fleet airworthy, maintenance planners have to schedule the maintenance checks for each aircraft and the associated tasks. In practice, these two complex problems are solved following the experience of planners,...

journal article 2021

document

Lookahead Approximate Dynamic Programming for Stochastic Aircraft Maintenance Check Scheduling Optimization

Deng, Q. (author), Santos, Bruno F. (author)

This paper proposes a lookahead approximate dynamic programming methodology for aircraft maintenance check scheduling, considering the uncertainty of aircraft daily utilization and maintenance check elapsed time. It adopts a dynamic programming framework, using a hybrid lookahead scheduling policy. The hybrid lookahead scheduling policy makes...

journal article 2021

document

Robust Long-Term Aircraft Heavy Maintenance Check Scheduling Optimization under Uncertainty

van der Weide, Tim (author), Deng, Q. (author), Santos, Bruno F. (author)

Long-term heavy maintenance check schedules are crucial in the aviation industry since airlines need them to prepare the required maintenance tools, workforce, and aircraft spare parts. However, most airlines adopt a manual approach to plan the heavy maintenance check schedules in current practice. This manual process relies on the experience of...

journal article 2021

document

Data-Driven Prognostics Incorporating Environmental Factors for Aircraft Maintenance

Bieber, M.T. (author), Verhagen, W.J.C. (author), Santos, Bruno F. (author)

During flights aircraft continuously collect data regarding operations, health status and system condition. Data-driven approaches typically applied to system specific sensor data provide a way to predict failures of aircraft systems. However, it is believed that some systems deteriorate faster when subjected to particular environmental...

conference paper 2021

document

An Adaptive Framework For Remaining Useful Life Predictions Of Aircraft Systems

Bieber, M.T. (author), Verhagen, W.J.C. (author), Santos, Bruno F. (author)

Prognostics for condition-based maintenance does not only consist of prognostic algorithms but also involves steps such as data pre-processing, feature extraction, and feature selection, all of which contribute to the quality of the remaining useful life estimation. This process requires a lot of expertise and technical knowledge, which for many...

conference paper 2021

document

Airline disruption management: A literature review and practical challenges

Hassan, L. K. (author), Santos, Bruno F. (author), Vink, J. (author)

Airline disruption management is an active field of research. In recent years, there has been an increase in publications, in particular, in of works integrating two or more resources (i.e., aircraft, crew, passengers) in the recovery analysis. Given that more than 50% of the papers have been published after the last literature review paper ...

review 2021

document

A bin packing approach to solve the aircraft maintenance task allocation problem

Witteman, Max (author), Deng, Q. (author), Santos, Bruno F. (author)

This paper addresses the scheduling of aircraft maintenance tasks that must be carried out in multiple maintenance checks to keep a fleet of aircraft airworthy. The allocation of maintenance tasks to maintenance opportunities, also known as the task allocation problem (TAP), is a complex combinatorial problem that needs to be solved daily by...

journal article 2021

document

Aircraft maintenance check scheduling using reinforcement learning

Andrade, Pedro (author), Silva, Catarina (author), Ribeiro, Bernardete (author), Santos, Bruno F. (author)

This paper presents a Reinforcement Learning (RL) approach to optimize the long-term scheduling of maintenance for an aircraft fleet. The problem considers fleet status, maintenance capacity, and other maintenance constraints to schedule hangar checks for a specified time horizon. The checks are scheduled within an interval, and the goal is...

journal article 2021

document

A practical dynamic programming based methodology for aircraft maintenance check scheduling optimization

Deng, Q. (author), Santos, Bruno F. (author), Curran, R. (author)

This paper presents a practical dynamic programming based methodology to optimize the long-term maintenance check schedule for a fleet of heterogeneous aircraft. It is the first time that the long-term aircraft maintenance check schedule is optimized, integrating different check types in a single schedule solution. The proposed methodology...

journal article 2020

document

Dynamic aircraft recovery problem - An operational decision support framework

Vink, J. (author), Santos, Bruno F. (author), Verhagen, W.J.C. (author), Medeiros, I. (author), Filho, R. (author)

This paper presents a new approach for solving the recovery of the airline schedule when disruptions have occurred. The goal is to develop an operational tool that provides the airline with a solution in less than one minute. The proposed recovery model uses a heuristic that iteratively solves selections of the airline's fleet in order to...

journal article 2020

document

Portfolio-based airline fleet planning under stochastic demand

Sa, Constantijn A.A. (author), Santos, Bruno F. (author), Clarke, J.B. (author)

Airlines operate their fleet of aircraft over a relatively long time horizon during which the realized stochastic demand has the potential to profoundly impact the airlines’ financial performance. This makes the investment in a fleet of aircraft a highly capital-intensive long-term commitment, associated with inherent risks. We propose an...

journal article 2020