The role of schedule delays on passengers’ choice of access modes: A case study of Japan’s international hub airports

We empirically study passenger modal-choice behavior to access an international hub airport, by using stated preference (SP) data and by constructing a binomial logit model. We found that passenger modal choice is affected by the service level of the access modes: travel time, travel cost, waiting time, and delay cost. The results also indicate that if passengers choose access mode in advance they consider service frequency: departure timing from home, and the arrival timing at the airport. Moreover, our results indicate that travelers’ willingness to pay for saving time differs by time of a day. They are apt to pay more in the morning than in the afternoon. These outcomes must contribute to improve the access flight service from local to hub airports to handle the needs of passengers.     

Assessment of passenger benefits brought about by international airport projects

This study sets forth a method to calculate the passenger benefits of an international airport project and assesses the passenger benefits brought about by two international airport projects.An international airport project mainly increases the number of flights and the possibility of determining convenient timetables. It does not significantly decrease the flight time of international travel. Thus, the user benefits brought about by an international airport project cannot be expressed by the conventional concept of ‘traveling time’, which is the term generally used.In this study, the ‘Expected Value of Traveling Time’ and ‘Expected Value of Generalized Cost’ are presented as indexes to evaluate improvements in convenience brought about by international airport projects. The passenger benefits of two airport projects in Japan are measured by consumer surplus calculated from the demand function using these indexes.These indexes are accurately calculated taking into consideration factors such as scheduling connections between domestic and international transport, and so enable a grasp not only of reductions in flight time, but also of passenger benefits resulting from international airport projects, such as increases in the number of flights and reductions in the time required to make transfers during domestic travel.     

Optimizing flight equencing and gate assignment considering terminal configuration and walking time

Operating airline hub-and-spoke networks (HSN) rather than direct flights among city pairs may significantly reduce supplier cost; however, passengers' travel time may significantly increase due to increased transfer and in-flight time. The costs considered in this study are hub-related and incurred by passengers and aircraft (i.e., passenger transfer, flight dwelling, and gate occupancy). The objective is to minimize the total cost by optimizing flight sequence (i.e., arrivals and departures) and gate assignment, while considering transfer speed, transfer demand, flight size, gate size and terminal configuration. A real-world HSN whose hub airport (HA) is located at Xianyang International Airport (XIY) in Xi'an, China is analyzed. The optimized solutions and their relations to various model parameters are explored.     

Supply-and-demand models for exploring relationships between smaller airports and neighboring hub airports in the U.S.

Airport passenger leakage is the phenomenon of air passengers choosing to travel longer distances to access more extensive air services offered by airlines at an out-of-region hub (or, substitute) airport, instead of using their local airports. Airport leakage can cause further reduction in services offered by airlines at a local airport, thereby causing even further leakage, and so on, which can significantly impact an airport's role in the growth of the local economy. This paper explores the geographic and operational attributes of local-and-substitute airport pairs in the United States, explicitly accounting for the interactive feedback relationship between passenger volumes and air service characteristics that contribute to the onset, persistence, and exacerbation of airport passenger leakage. A two-stage least squares regression model of air passenger demand at small- and medium-sized airports is first presented, where local passengers may travel by vehicle to larger, out-of-region hub airports. The results confirm that airfare and passenger volume relationships exist between the local and substitute airport pairs included in the dataset, and that lower airfares at the substitute airport have a greater impact on airport choices made by larger travel groups. They also suggest the existence of positive feedback in that if an airport attracts increasingly smaller passenger numbers with fewer air services and fewer air services with fewer passengers, without external intervention airport leakage impacts may be irreversible and exacerbate over time. A conceptual market share equilibrium analysis is used to illustrate the mechanisms of a direct two-way feedback relationship between passenger volumes at a local airport and air service characteristics at both the local and substitute airports. With data, this quantitative framework can help guide airport planners in further assessing and verifying suspected passenger leakage issues at their airport. The results suggest that without intervention, airport leakage impacts may be difficult to reverse; further exacerbating the trend are technological advancements that make driving cheaper and easier (connected and autonomous vehicles). However, the results can also guide planners in choosing the types and degrees of infrastructure investments and airline incentives that may be used to expand or retain air services to attract passengers.     

Hub competition and travel times in the world-wide airport network

The aim of this work is to measure the competition between airport hubs based on an analysis of travel times in the world-wide airport network. By considering the minimum travel time required to connect each pair of airports, it is possible to create new measures of hub competition, separating the effects of hub position and temporal coordination. This analysis was carried out at the global level, considering all 232 airports with more than 3 million seats yearly offered in departure flights in 2008, and also in relevant geographic markets. The results show a high level of competition among the most important world airports, but the major airports of Europe have a geographical advantage in relation to world markets over the major American and Asian airports. We also show that airports located in different continents often compete for the same origin–destination markets. Geographical position appears to be the most important variable explaining hub performance. Secondary hubs show a higher degree of specialization towards specific markets.     

The opening of direct flights across the Taiwan Strait: the impact on the global role of Taiwan’s international airport

Scheduled direct flights between Taiwan and Mainland China were halted for six decades and restarted in December 2008. The Taiwan’s government has a policy of developing Taoyuan International Airport (TPE), the major international airport in Taiwan, as one of main hubs in East Asia, based on the airport’s access to Mainland China. To assess whether the airport is progressing toward meeting the set expectation, this study evaluates the changes in airline networks of the TPE after the opening of direct flights across the Taiwan Strait. The time-dependent earliest arrival time algorithm is applied to global flights in 2004, 2008, and 2012. Empirical evidence demonstrates that providing direct flights across the Taiwan Strait has significantly increased accessibility from TPE to airports in China, but did not improve the centrality of TPE. Additionally, the transfer dependency of TPE on other airports is increasing significantly. This result was based on two major reasons: the first involves the Chinese government’s refusal to allow Chinese citizens to use airports in Taiwan as transfer points to and from other countries and the second reflects the competitiveness among airports and airlines in the region. The key finding is that political exclusion of airline use by external governments via travel regulations adversely influences the development of an airport as a global hub.     

Modeling the joint choice of access modes and flight routes with parallel structure and random heterogeneity

This study focuses on the influence of ground access transportation on air travel. The error components logit model with parallel structure is first adopted to formulate the joint choice behavior of access, airports, and flights. The proposed model proves to be effective in exploring interdependence between choice dimensions and travelers heterogeneity. The empirical results indicate that fare discounting should be introduced at the city airport and the frequency of existing flight routes should be increased. To benefit the hub airport, authorities of the new airport mass rapid transit system should reconsider the tradeoff between time and cost for express trains.     

Route optimization for energy efficient airport shuttle operations – A case study from Dallas Fort worth International Airport

The objective of this research is to reduce energy consumption from intra airport shuttle operations by optimizing routes and schedules, without compromising on passenger travel experience. To achieve this objective, we propose an optimization model that generates optimal airport shuttle routes for a given set of constraints and a discrete-event simulator that evaluates the optimal shuttle routes in a stochastic environment to understand the tradeoffs between the amount of time passengers wait for shuttles, and shuttle energy consumption. The proposed optimization model and stochastic simulation are tested using shuttle route data provided by the Dallas Fort Worth International Airport. Results indicate that optimized routes can lead to a 20% energy reduction in shuttle operations with a modest 2-min increase in average shuttle wait times. The optimization model and simulator presented here are designed to be generalizable and can be adapted to optimize shuttle operations at any major airport.     

Simulation method for dispatching national border security manpower to mitigate manpower shortage

Recently, a record number of passengers have entered and exited Taiwan from Taiwan Taoyuan International Airport (TTIA). The number of passengers from Taiwan to mainland China has increased largely because of the improvement of cross-strait cultural interaction and other policies, as well as the opening of direct flights. Not only located in the transport hub of the East Asia Taoyuan International Airport is becoming more important and can provide 24 h Airport service, but also airport immigration officers must take 24 h shift to carry out the passenger document inspection requirement, Immigration officers can be fatigued by long shifts, thus negatively affecting border security clearance efficiency and work performance. Consequently, innovative management practices regarding immigration officers are necessary to strengthen international cooperation against terrorism. This study used system simulation Delphi interviews and a heuristic algorithm to determine the required number of airport immigration officers during a fixed passenger waiting time, for improving the efficiency and stability of airport immigration officers who work to consolidate the border security of the country. The results showed that the utilization of airport immigration officers at Taiwan Taoyuan International Airport is higher than 97.99%, and their work hours have been reduced by more than 54.68%. These results proved that using a system simulation can reduce long work shifts and negligence, which can lead improved border security and airport service quality. Additionally, the simulation results that when the National Immigration Agency and Taiwan Taoyuan International Airport implement the biometrics verification system for noncitizens, significant manpower shortages are expected. These shortages can cause complaints from customers and result in a negative image of the quality of airport service. Assigning priority to setting the E-GATE system to compensate for the lack of immigration officers would result in more efficient and effective border security.     

The sky is the limit? The determinants and constraints of European airports commercial revenues

This study investigates the determinants of commercial and retail airport revenues from real estate operations. Aviation revenues per passenger are mainly determined by the national income per capita in the area where the airport is located, the percentage of leisure travelers and the size of the airport. Main drivers of commercial revenues per passenger include the number of passengers passing through the airport, the ratio of commercial to total revenues, national income, the share of domestic and leisure travelers and the number of flights. These results are in line with previous findings of a negative influence of business travelers on commercial revenues per passenger. We also find that a large amount of retail space per passenger is generally associated with lower commercial revenues per square meter confirming decreasing marginal revenue effects. Real estate revenues per passenger are positively associated with national income per capita at airport location, share of intra-EU passengers and percent delayed flights.     

Integrated recovery of aircraft and passengers after airline operation disruption based on a GRASP algorithm

This paper considers the integrated recovery of both aircraft routing and passengers. A mathematical model is proposed based on both the flight connection network and the passenger reassignment relationship. A heuristic based on a GRASP algorithm is adopted to solve the problem. A passenger reassignment solution is demonstrated to be optimal in each iteration for a special case. The effectiveness of the heuristic is illustrated through experiments based on synthetic and real-world datasets. It is shown that the integrated recovery of flights and passengers can decrease both the recovery cost and the number of disrupted passengers.     

Airport choice and flight connectivity among domestic and international passengers – Empirical analysis using passenger movement survey data in Japan

This paper presents an empirical analysis of airport choice and passenger movement on international flights from local cities in Japan to Narita and Haneda Airports in the Tokyo metropolitan area. This is the first study to evaluate airport choice behavior in Japan empirically by using the micro data collected by Japan’s Ministry of Land, Infrastructure, Transport and Tourism in 2010 (i.e., when time slots for international long-haul flights were first assigned at Haneda). The analysis confirms that flight connectivity is a crucial element in airport choice.Further, Japanese airlines and their associated alliances are able to attract passengers arriving from local cities by using Haneda airport. Above all, we find that the introduction of long-haul international flights from Haneda has met the needs of a number of passengers arriving from local cities in Japan owing to the convenience of the domestic flight network, especially for business purpose passengers.     

Airline delay management problem with airport capacity constraints and priority decisions

This paper deals with the Airline Delay Management Problem (ADMP), which can be described as the task of dealing with daily airline operational delays and deciding whether to delay subsequent flights at a hub airport or to have them departing on time. An innovative integer linear programming approach is presented to the capacitated case of the ADMP and airport limitations in terms of bay availability, taxiway capacity and runway separation are incorporated to represent capacity constraints. Fuel cost, passenger compensation, and passenger inconvenience costs are included in the objective function. The decision variables include the re-timing of flight departures and arrivals, the use of the airport capacity over time and the rebooking of passengers in case of missed connections. To guarantee the linearity of the optimization model and fast computational times, a receding horizon modeling framework is adopted. The approach is applied to a case study using real operational and passenger data from an international hub-and-spoke carrier. The case study shows the capability of the linear model to deal with a complete day of operations within a few minutes. The results suggest that the proposed approach can lead to cost reductions of almost 30% during recovery, when compared with the solution from the airline. In addition, a sensitivity analysis is provided to investigate the impact of not including passenger inconvenience costs and of reducing runway capacity.     

Airport security screening and changing passenger satisfaction: An exploratory assessment

Since September 11, 2001, airport screening procedures in the US have been continuously evolving. For example, the passenger screening process is now trying to strike a balance between security and customer service (i.e. minimizing wait times). This balancing act has important implications not only for passenger safety, but also for the financial stability of an airline industry that is faced with volatile energy prices and sometimes burdensome labor agreements. Using data from 2002 and 2003, we estimate multinomial logit models to uncover factors that determine passenger satisfaction at security screening points. Our findings show that, while wait times at security screening points are significant determinants of passenger satisfaction, many other factors come into play. Moreover, the results show that the determinants of customer satisfaction are not stable over time. This suggests that further refinements in airport screening procedures should give careful consideration to the factors underlying passenger satisfaction, and how these might change over time, rather than focusing exclusively on minimizing wait times at passenger screening points.     

Living “up in the air”: Meeting the frequent flyer passenger

This paper uses a large database of approximately 37,000 passengers and three different estimates to analyse the characteristics of the frequent flyer and the differences between frequent flyers and occasional flyers. The results show that frequent flyers are middle-aged men with a high level of education who take domestic flights for business reasons at both hub and regional airports, where they make a purchase and/or consume F&B. Frequent flyers fly on both low-cost and traditional airlines, are more likely to stay overnight at a relative's or friend's home and travel to the airport by private or rented car.     

Flight and passenger efficiency-fairness trade-off for ATFM delay assignment

This paper studies trade-offs between efficiency (performance) and fairness (equity), when assigning ATFM delay pre-tactically (on-ground at origin airport) due to reduced airport capacity at destination. Delay is assigned as the result of the optimisation of a deterministic multi-objective problem considering flight and passenger perspectives when defining objectives of performance and fairness. Two optimisation cases are presented: one where objectives are based on flight metrics, and another one where they are based on passenger metrics. The paper defines and analyses efficiency-fairness trade-offs: the concepts of price of fairness for flights and passengers are defined as the percentage of efficiency loss due to the consideration in the optimisation of fairness; whereas the price of efficiency is considered as the fairness loss relative to the maximum value of the fairness metric, when considering flight or passenger delay in the optimisation. The optimisation model is based on the ground holding problem and uses various objective functions. For performance, total delay for flights (considering reactionary delay), and total delay for passengers (considering outbound connections) are defined. For fairness, the deviation of flight arrivals from a Ration By Schedule solution, and the deviation of delay experienced by passengers with respect to the one obtained in an RBS situation are used. An illustrative application on traffic at Paris Charles de Gaulle airport, a busy European hub airport, and including realistic values of traffic is modelled. A comprehensive trade-off analysis is presented. Results show, how in some cases, gains on one stakeholder can be achieved without implying any detriment on the other one. Passengers are more sensitive to the optimisation and hence, their consideration when assigning delay is recommended. Further research should explore how to combine flight and passenger indicators in the optimisation and consider how the lack of data availability could be mitigated.     

Estimating the marginal costs of airport operation using multivariate time series models with correlated error terms

This paper explores insights about marginal airport costs that can be gained by analysing labour inputs and their variability. Based on hourly cost and traffic data for the airport of Helsinki, a multivariate time series approach is used incorporating correlated error terms to account for random shocks such as delays. We found for most airport services a linear relationship between labour input and aircraft movements, except for producing passenger services for international departing flights where a cubic cost relationship was estimated. The findings are comparable with earlier studies for US airports.     

The effect of de-hubbing on airfares

This paper studies the price effect of de-hubbing, which occurs when an airline ceases hub operations at an airport. We develop a simple theoretical model to study the impact of de-hubbing on prices and quantities of direct flights at the hub airport. Using an event study of seven cases of de-hubbing between 1993 and 2009, we analyze how average airfares change following de-hubbing. Consistent with the theoretical implications, the empirical results suggest that airfares decrease when there is a low-cost carrier presence at the de-hubbed airport, whereas airfares increase when the de-hubbed airport is not serviced by a low-cost carrier.     

Optimising flight connection times in airline bank structure through Simulated Annealing and Tabu Search algorithms

In hub and spoke airline networks, flight arrivals and departures generally have a bank structure to increase connections among spoke cities through a hub airport in order to provide cheaper service for higher volumes of air traffic. In this study, we introduce the airline bank optimisation problem with a novel mathematical model for improving flight connection times. The mathematical model aims to minimise the total connection times for transfer passengers and generates flight schedules regarding slot capacities in the hub airports. Since the problem is a combinatorial optimisation problem NP-hard and computational complexity increases rapidly for real-world problems, we employ the simulated annealing and the tabu search algorithms to achieve better solutions in a reasonable time. We generate sub-problems using real-world data and investigate the effectiveness of the algorithms. Finally, we present the results of a real case study of a Turkish airline company which has a hub airport connecting the flights between Middle Eastern and European cities.     

Understanding air travellers' trade-offs between connecting flights and surface access characteristics

This paper reports on a study which seeks to improve our understanding of how people choose between different kinds of flight at competing airports, and how their choices are affected by access conditions. In particular, using stated choice data collected in Scotland, it investigates whether improving surface access to regional airports that are in relatively close proximity to one another (Glasgow and Edinburgh) leads people to avoid taking indirect flights from their nearest airport in favour of direct flights from an alternative airport. In line with expectations, our estimation results from Cross-Nested Logit models show strong aversion to connecting flights, resulting in a willingness to either pay higher fares for direct flights or accept non-trivial increases in access time. For the latter, even without the potential new direct rail link between the two airports, current access times are such that a scenario where direct flights were only available at the non-home airport, a substantial share of passengers would choose to travel from the alternative airport.