Air Transport Demand Research Articles

Air travel demand forecasting in the presence of Public Service Obligation (PSO)

Knowing the potential evolution of air transport demand is necessary in order to ensure the positive effects that are generated by air transport itself, in terms of economic and social development. There are several air transport demand forecasting models, which differ from each other in terms of time, available data and the aspects to be analysed. The aim of this study is to create forecasts that can help government authorities to formulate air transport development policies. This paper focuses on a regional context — Sardinia — the second largest island in the Mediterranean. A large part of its economic and social development potential (tourism-related) is based on breaking its isolation by substantially improving air transportation services. In particular, the originality of these forecasts lies in the attempt to interpret a context characterised by different factors influencing the air transport market. Public Service Obligation (PSO) (Art. 4 RC 2408/92) was first imposed in Sardinia in 2002, on several domestic routes. Low cost companies have been operating since 2007, and some of them took advantage of public subsidies to develop new routes. During the same period, the three major Sardinian airports were expanded and improved. This paper provides a detailed, descriptive analysis of air transport demand evolution at Cagliari’s airport (1995–2014). Based on this analysis, several regression models for aggregate data have been specified and calibrated, distinguishing between domestic and international passengers.

The Causality Analysis of Air Transport and Socio-economics Factors: The Case of OECD Countries

Abstract Air transport is one of the most important industries in the world with its rapid growth, and direct and indirect contribution to world economy. In other words, GDP, tourism and employment are the key factors causing that growth in air transport and an increase in those factors boost the demand for air transport. However, uncertainty in economy, rising unemployment and increased terrorist attacks towards tourism would be a big threat to the growth of air transport in the future. To understand the importance of the mentioned factors, we first aim to apply an econometric approach which is panel Granger causality analysis. To achieve that, data from World Bank data set for OECD countries between the year of 2000 and 2013 is used in this study. We apply Pesaran CDLM test and Friedman’s test which are preferred when the number of units (N) is higher than the time (T) to test cross-sectional dependence and we then perform Granger causality analysis in order to see whether there is a causal relationship (unidirectional or bidirectional) or not among air transport, tourism, economic growth and employment. Econometric results indicate that there is a unidirectional short run causal relationship between economic growth, tourism, employment and air transport and that those factors play an important role in the growth of air transport. In this paper, we also aim to discuss the future challenges for air transport within the frame of econometric results and statistical analysis.

Air transportation demand forecast through Bagging Holt Winters methods

This paper expands the fields of application of combined Bootstrap aggregating (Bagging) and Holt Winters methods to the air transportation industry, a novelty in literature, in order to obtain more accurate demand forecasts. The methodology involves decomposing the time series into three adding components: trend, seasonal and remainder. New series are generated by resampling the Remainder component and adding back the trend and seasonal ones. The Holt Winters method is used to modelling each time series and the final forecast is obtained by aggregating the forecasts set. The approach is tested using data series from 14 countries and the results are compared with five methodology benchmarks (SARIMA, Holt Winters, ETS, Bagged.BLD.MBB.ETS and Seasonal Naive) using Symmetric Mean Absolute Percentage Error (sMAPE). The empirical results obtained with Bagging Holt Winters methods consistently outperform the benchmarks by providing forecasts that are more accurate.

Interdependencies of demand for international air transportation and international tourism

This article analyses the interdependency of demand for two of the leading traded services globally: international travel (transportation) and international tourism. Based on the Almost Ideal Demand System, the study models transport and tourism demand simultaneously for a range of countries: Australia, New Zealand, the United States and the United Kingdom. Overall, tourism demand is found to be more expenditure and price-elastic than is the demand for transport services to the same destination. The cross-price elasticities indicate significant interdependencies of demand between transport and tourism, and between destinations. Overall, the cross-price elasticities confirm the complementarity between transport demand and tourism demand. However, in the cases of the UK demand for the United States and the US demand for the United Kingdom, substitutability between the two demand types is found.

Exergy-based Sustainability Analysis of a Low-bypass Turbofan Engine: A Case Study for JT8D

The growth in demand for air transport is a problem for the global and local environment. There are, moreover, fundamental conflicts with sustainable development objectives. Sustainability demands a sustainable supply of energy without causing negative environmental impacts of aircrafts and its engines. In this paper, an investigation of exergo-sustainability indicators is reported for a low bypass (0.96 to 1) turbofan engine with 72kN thrust force. Six selected exergetic indicators are selected for the analysis. The study is based on three approaches: energy, exergy and sustainability. In this regard, considering thermodynamics laws and Brayton cycle equations, the exergy efficiency of the engine is 11% having waste exergy ratio of 0.348. In addition, exergetic sustainability index of the low bypass turbofan engine is found to be 0.316, while environmental effect factor is calculated to be 3.163. On the other hand, the recoverable exergy amount of the engine is zero since the emissions released from fan bypass duct and core engine exhaust cannot be recoverable in the engine.

A comparative analysis between helicopter and seaplane for passenger transport

Purpose This study aims to develop a methodology to compare the feasibility of helicopter and seaplane regular transport of passengers towards destinations across a remote regional tourist context, where a lack of road and rail infrastructure make these alternative forms of air transport competitive. Design/methodology/approach The authors use a modal split model identifying the quota of passengers that potentially could utilize these two types of services, determined on the basis of previous studies on air transport demand. A technical analysis regarding transport supply is performed to identify the predominant features that should characterize helicopter/seaplane performances. An optimization model is applied to identify the routes that could overcome the breakeven point considering each of the two means of transport. The paper also takes into account the importance of each type of service and its influence on flight infrastructure costs. Findings Helicopter and seaplane services could improve the access for tourists with high values of time. The helicopter transport could capture a market share ranging from 5 to 20 per cent of tourist travel demand (the amphibian seaplane from 1 to 14 per cent). The shuttle services could be profitable especially for those regional origin–destination pairs involving the two major airports and the most UNESCO visited locations such as Agrigento and the Aeolian Archipelago (into the analyzed context of Sicily). The comparison between the two modes of transport shows that the helicopter has best performances and the seaplane has to land/take-off from sea. Research limitations/implications The lack of data on the performances of the whole world production of seaplanes and helicopters (such as Russian, Chinese or US old machines) could give a distortion of the result. On the other hand, all mostly used machines in the world at the moment are considered. A survey on the fear of flight and on the choice between the two different forms of air transport could give a more precise result. Practical implications From an economic point of view, an operator could choose with more confidence the means of transport to use under different conditions. The activation of passenger services with seaplanes and helicopters can give an impulse to the growth of little operators and to the tourism. So, this study could be a starting point for authorities to plan a regional network of little general aviation airfields and seadromes (located in the great lakes or near the ports) near the major tourist locations. It could make possible to develop a synergic regional commuting traffic involving the seaplane and the helicopter. Social implications Seaplanes and helicopters represent the most important means of transport when poor accessibility conditions and need of ready and fast connections coexist, for example, the commuting between airports and remote regions or downtowns with high tourist or business impact. The activation of passenger services with seaplanes and helicopters can give an impulse to the growth of little operators and to the tourism, consequently to the regional accessibility and economy. Originality/value There is a lack of studies involving the comparison between seaplanes and helicopters. This study could represent an important means to analyze the parameters that influence the possibility of activation for this kind of services and to find the factors that influence the feasibility of business with the two different machines. The encouraging performances of the flying boat suggest a future development of an innovative model of medium- and/or high-capacity amphibian seaplane dedicated to passenger transport. It should have take-off/landing performances less dependent on the sea state.

Risk management: Where are the greatest risks in the airport development lifecycle and what factors should be front of mind?

Airports continue to be built or expanded around the world in order to match capacity to the continuous growth of demand for air transportation. Constructing and delivering an airport is no easy task, however. The complexity, sheer size and budget of such an endeavour put this type of project in the category of a mega project — and, consequently, in the category of a risky business. Risk, however, is manageable. The key to succeeding in managing uncertainty and its potential consequences is to understand what the greatest risks are in an airport development project — and, specifically, where they are in each stage of the project’s life cycle — and then address them with best business and project management practices. In doing so, three major risk factors — systems integration, project interface management and people and operational readiness — require more attention and specific approaches.

Control and optimization algorithms for air transportation systems

Modern air transportation systems are complex cyber-physical networks that are critical to global travel and commerce. As the demand for air transport has grown, so have congestion, flight delays, and the resultant environmental impacts. With further growth in demand expected, we need new control techniques, and perhaps even redesign of some parts of the system, in order to prevent cascading delays and excessive pollution.In this survey, we consider examples of how we can develop control and optimization algorithms for air transportation systems that are grounded in real-world data, implement them, and test them in both simulations and in field trials. These algorithms help us address several challenges, including resource allocation with multiple stakeholders, robustness in the presence of operational uncertainties, and developing decision-support tools that account for human operators and their behavior.

PERFORMANCE ANALYSIS OF MAJOR AIRLINE COMPANIES IN UAE WITH REFERENCE TO PROFITABILITY, LIQUIDITY, EFFICIENCY, EMPLOYEE STRENGTH AND PRODUCTIVITY

The demand for air transport has been consistently increasing in UAE and has made significant growth in the aviation sector in terms of expansion and modernization. Within Dubai’s services sector, transport ranks first accounting for 14.8% of Dubai’s GDP in 2014.As per the Economics Report commissioned by Emirates and Dubai Airports, aviation sector is expected to contribute $53.1 billion to Dubai’s economy, 37.5 per cent to its GDP and will support over 750,000 jobs by 2020. The present study makes a comparative analysis of the top airline companies in UAE – Emirate Airlines and Air Arabia in terms of profitability, liquidity, efficiency and also Etihad Airways on employee strength and productivity from 2010 to 2014.Dubai’s aviation sector is projected to support over 1,194,700 jobs by 2030 and the total economic impact on UAE is expected to increase to $88.1 billion. The financial performance indicators of Emirates Airlines and Air Arabia has been compared and further analyzed to see if there is any significant impact of the macroeconomic indicators on the financial performance of the airline companies. Companies can create wealth either by increasing profit per employee or by increasing the number of employees earning such profits, or both.

Causality between economic growth and air transport expansion: empirical evidence from Mexico

This paper analyses the effects in the long-run between air transport demand and the economic growth in Mexico. Using quarterly data from 1995qIII to 2013qIV, the study investigates possible causal relationships between real GDP and number of air passengers in arriving and departing from Mexican airports. Johansen cointegration analysis shows the existence of one cointegrated vector where the corresponding elasticities are positive. The study shows that the causality relationship is positive and bidirectional. Impulse response analysis shows that an increase in the magnitude of air transport expansion in Mexico produces a positive effect on economic growth in the country.

Change management in the ATM system: integrating information in the Preliminary System Safety Assessment

The increasing air transport demand suggests looking at air traffic management (ATM) as a continuously and evolving process. The procedures and equipment we use today will not continue coping with next air traffic requirements. It is thus necessary to provide ATM services for the current operating scenarios. This paper proposes a systematic tool, i.e., the preliminary system safety assessment tool (PSSA-T) to help the decision makers in evaluating safety implications of system changes. PSSA-T relies on the definition of two indexes, based on the aerospace performance factor (APF) methodology. These indexes allow a structured safety analysis of any proposed change: the first compares the evolutionary scenario with the current one and the second one considers the effects of a failure of the changed agent (equipment or procedure) in a future scenario. The paper illustrates a case study for the flight progress strip (FPS) change to electronic FPS.

Change management in the ATM system: integrating information in the preliminary system safety assessment

The increasing air transport demand suggests looking at air traffic management (ATM) as a continuously and evolving process. The procedures and equipment we use today will not continue coping with next air traffic requirements. It is thus necessary to provide ATM services for the current operating scenarios. This paper proposes a systematic tool, i.e., the preliminary system safety assessment tool (PSSA-T) to help the decision makers in evaluating safety implications of system changes. PSSA-T relies on the definition of two indexes, based on the aerospace performance factor (APF) methodology. These indexes allow a structured safety analysis of any proposed change: the first compares the evolutionary scenario with the current one and the second one considers the effects of a failure of the changed agent (equipment or procedure) in a future scenario. The paper illustrates a case study for the flight progress strip (FPS) change to electronic FPS.

O Congestionamento Aéreo: Uma Visão Geral

This article is a literature review of the air congestion delay and its costs. Air congestion is a worldwide problem. Its existence brings costs for airlines and discomfort for passengers. With the increasing demand for air transport, the study of air congestion has attracted the attention of many researchers around the world. The cause for the delays is erroneously attributed only to the lack of infrastructure investments. The literature review shows that other factors such as population growth, increasing standards of living, lack of operational planning and environmental issues exercise decisive influence. Several studies have been conducted in order to analyze and propose solutions to this problem that affects society as a whole.

Effects of noise information provision on aircraft noise tolerability: Results from an experimental study

The maximum number of flights tolerated by airport-area residents is affected by their access to information concerning their neighbors who are affected by the noise. This study explored the effects of providing descriptions of noise exposure conditions on the tolerance of aircraft noise by residents living near Manila Airport in the Philippines. A questionnaire assessed different levels of noise in a hypothetical situation involving the affected zones. Face-to-face interviews were conducted using prerecorded aircraft noise presented via headphones. The information about the overall noise situation at an airport lowered the tolerance of overhead flights, compared to the baseline levels. The participants tolerated more flights when they were informed about the situation of people who were more severely affected by the noise than they were. This tendency strengthened with an increase in the severity of the noise situation in other areas. The economic benefits associated with an increase in air transport demand were also observed to boost noise tolerance. The findings provide insights into proper information provision, which should benefit the noise-management personnel of airports.

Stated-preference analysis to estimate the domestic transport demand following the future entry of LCCs and the inauguration of the Linear Chuo Shinkansen in Japan

Using a stated-preference survey, we examine changes in air transport demand by the entry of low cost carriers into domestic service, and with the beginning of operation of the Linear Chuo Shinkansen. In order to construct a choice model, we estimate the Nested-Logit model parameters by the two kinds of travel purposes in order to consider the differences in the price-sensitivity between business and non-business travelers. Simulation results for the each targeted OD vary in the shares of each transportation mode, depending upon the travel times, the aviation network, travel purpose. Non-business travelers who are more price-sensitive are less likely to choose the Linear Chuo Shinkansen with higher fares. On the route between the metropolitan area and Kinki area, total aviation demand will increase by the entry of LCCs to/from Tokyo-Haneda airport even when the Linear Chuo Shinkansen begins operating, showing that the development of the Linear Chuo Shinkansen service will not prevent strong growth in aviation demand for the trunk domestic routes.

Is increasing aircraft size common practice of airlines at congested airports?

If the overall demand for air transport grows, but additional airport capacity is not available at congested airports, we could assume that airlines will offer flights with more seats in order to cope with the demand. An analysis of frequency and average seat capacity developments at congested, and not yet congested airports, has shown that the hypothesis of bigger aircraft being used in congested situations is valid in most instances, although not at all airports. The objective of this paper is to report on an analysis of the development of average seat capacity at congested airports, in contrast to the situation at not yet congested airports, and to find out the reasons for airlines increasing the number of seats at congested airports, by means of a statistical model using variables including the degree of airport congestion and average flight distance.

4D Approaching Trajectory Design in Terminal Area Based on Radar Data

The terminal area is always a hot research topic by aviation experts all over the world. As the rapid growth of the demand of air transportation, the terminal area becomes busier than ever. The results are flight delays and cancellations. One of the solutions is to design a 4D trajectory for each flight. Under the four dimensional operation, the flights can fly more precisely and be arranged more closely so that the terminal area can hold more aircrafts. With the development of the technology of communication, navigation and surveillance, the flight of four-dimensional operation is possible. This paper presents a data-based method of 4D approach trajectory design in terminal area.

Aircraft and engine economic evaluation for fleet renewal decision-making and maintenance contract valuation

The fleet acquisition process represents a major gamble for airlines and aircraft leasing companies due to the fixed assumptions made when business plans are laid out and the abundance of uncertainties both at the technical and market levels. Indeed, the evaluation of aircraft and engine acquisitions is riddled with uncertainties regarding the product development (development schedule), the economic performance of the assets once in operations (operating cost), and the demand for air transportation. The trend in recent years has been for original equipment manufacturers to offer contracts and guarantees during sales campaigns that limit the exposure of airlines to technical uncertainty and that shift some of the operating risks from the airlines to the manufacturers. Airlines have embraced these “power-by-the-hour” maintenance contracts because they offer a way to mitigate operating risks and to anticipate cash outflows. Estimating the fair value of these contracts is paramount due to the significant risks faced by companies underwriting them. At the same time, valuing them is a daunting task due to the uncertainty regarding maintenance costs and their sensitivity to both the operations and the operating environment. Traditional evaluation methods are not always well adapted to perform these evaluations as they do not capture the problem in its entirety and they tend to oversimplify by using generic routes and surrogate models. This paper simultaneously proposes a customer-centric methodology to properly evaluate long-term aircraft and engine investments and a real-options inspired methodology to value long-term maintenance contracts and manufacturer guarantees.

Improved rolling horizon approaches to the aircraft sequencing problem

In a scenario characterized by a continuous growth of air transportation demand, the runways of large airports serve hundreds of aircraft every day. Aircraft sequencing is a challenging problem that aims to increase runway capacity in order to reduce delays as well as the workload of air traffic controllers. In many cases, the air traffic controllers solve the problem using the simple "first-come-first-serve" (FCFS) rule. In this paper, we present a rolling horizon approach which partitions a sequence of aircraft into chunks and solves the aircraft sequencing problem (ASP) individually for each of these chunks. Some rules for deciding how to partition a given aircraft sequence are proposed and their effects on solution quality investigated. Moreover, two mixed integer linear programming models for the ASP are reviewed in order to formalize the problem, and a tabu search heuristic is proposed for finding solutions to the ASP in a short computation time. Finally, we develop an IRHA which, using different chunking rules, is able to find solutions significantly improving on the FCFS rule for real-world air traffic instances from Milano Linate Airport.

Imperfect reversibility of air transport demand: Effects of air fare, fuel prices and price transmission

There are recent evidence that air transport demand may not have a perfectly reversible relationship with income and jet fuel prices, as is assumed in most demand models. However, it is not known if the imperfectly reversible effects of jet fuel price are a result of asymmetries in the supply side, i.e., asymmetries in cost pass through from fuel prices to air fare, or of demand side behavioral asymmetries whereby people value gains and losses differently. This paper uses US time series data and decomposes air fare and fuel price into three component series to develop an econometric model of air transport demand that is capable of capturing the potential imperfectly reversible relationships and test for the presence or absence of reversibility. We find that air transport demand shows asymmetry with respect to air fare, indicating potential imperfect reversibility in consumer behavior. We also find evidence of asymmetry and hysteresis in cost pass-through from jet fuel prices to air fare, showing rapid increases in airfare when fuel prices increases but a slower response in the opposite direction.