An analysis of the greenhouse gas emissions profile of airlines flying the Australian international market

International commercial flights (with the exception of flights between countries in European Union including Iceland, Norway and Liechtenstein) are currently not subject to greenhouse gas emission reduction regulation. To formulate effective and efficiency policy to manage greenhouse gas emissions from air transport, policy makers need to determine the emissions profiles of all airlines currently flying into their country or region. In this paper, we use 2012 data on airlines' aircraft characteristics, passenger load and cargo load (obtained from statistics reported by Australian Government Bureau of Infrastructure, Transport and Regional Economics) to estimate the volume and carbon efficiency on each international route flying to and from Australia. This is the first study to use actual passenger and cargo load data to determine the greenhouse gas (specifically CO₂) efficiency of airlines operating in the Australian international aviation market. Airlines' CO₂ emission profile is dependent on many factors including but not limited to the aircraft used, payload, route taken, weather conditions. Our results reveal that the airlines’ CO₂ emission profile is not only dependent on the aircraft used and the number of passengers but also the amount of cargo on each flight.     

The implications of environmental costs on air passenger demand for different airline business models

Various environmental measures, including both regulations and fiscal instruments, have been used at airports globally to reduce the impacts of aircraft noise as well as aircraft engine emissions. Internationally, it is recognized that the costs of environmental and social externalities of air transport must be internalized and paid for by the aviation industry and its users. The use of noise related charges or taxes, which theoretically should be based on their respective social costs, has been proved to be effective at some European airports. This research aims to investigate the impacts of environmental costs, through environmental charges, on air passenger demand for different airline business models. The paper presents the mathematical models measuring the social costs of aircraft noise and engine emissions as a basis for setting up environmental charges. Six intra-European short-haul routes in two city pairs, namely London–Amsterdam and London–Paris, are selected for the empirical analysis. The environmental charges are then hypothetically applied to airlines with two different business models, full service carriers (British Airways and Air France-KLM) and low cost airlines (EasyJet). The results show that the potential percentages of demand reduction for both leisure and business passengers would be higher for Easyjet's markets, although with less environmental cost per passenger.     

Modelling airline flight cancellation decisions

In order to predict airline responses to Traffic Management Initiatives (TMIs), and reveal the underlying preference structures that shape these responses, we study US domestic airlines’ cancellation decisions in response to the Federal Aviation Administration (FAA)’s TMIs, in particular, to Ground Delay Programs (GDPs). By observing the actual flight-cancellation choices made by airline dispatchers, the airlines’ cancellation utility functions can be inferred through the use of binary choice models. The model captures how delays to a given flight and potential delay savings to other flights affect flight cancellation decisions. We also find larger, fuller, less frequent, shorter-distance, and spoke-bound flights are less likely to be cancelled, and that there is inter-airline variation in flight cancellation behaviour.     

Passenger use intentions for electronic tickets on international flights

The use of electronic ticketing has grown rapidly since the mid-1990s because of the savings in ticket distribution costs and handling overheads it offers compared to paper tickets. Most airlines have attempted to make electronic tickets the default ticketing method. This study uses an intention model for electronic ticketing that tests whether its intended adoption is a function of attitude, social support, and perceived confidence of air travelers. The results indicate that over 70% of passengers are likely to use electronic tickets; moreover, over 90% of current users have intentions to continue to use them on international flights.     

Characterizing the Brazilian airspace structure and air traffic performance via trajectory data analytics

This paper presents a data-driven approach for multi-scale characterization of the Brazilian airspace structure and air traffic operational performance from aircraft tracking data recorded by surveillance systems. Unsupervised learning is performed with a flight trajectory clustering analysis to automatically identify spatial traffic patterns in both the terminal and the en route airspace for major origin-destination pairs of the Brazilian air transportation system. Based on the as-flown route structure learned, quantitative metrics are developed to describe the structural efficiency of the airspace and the operational efficiency of the traffic flows. For this, actual flight trajectories are projected onto reference nominal trajectories in space and time. The results allowed for cross-route comparisons of air traffic flow efficiency across multiple flight phases as well as for the identification of causal factors for trajectory deviations from nominal routes. An interactive data analytics tool is also created to output performance statistics and air traffic visualizations. With the provision of a systematic data-driven approach for characterizing actual air traffic operations, the analytics framework is envisioned to assist airspace design and performance monitoring processes and to provide the basis for developing predictive capabilities in support of traffic flow management.     

Cost convergence in the US airline industry: An analysis of unit costs 1995–2006

Recent changes in the strategies of US airlines have led to a convergence of unit costs between the network legacy carriers and low-cost carriers. We develop a methodology for breaking down operating cost data reported by the airlines and argue that certain cost categories must be excluded to make a valid comparison between the carrier groups. We find significant evidence of convergence in unit costs excluding fuel and transport-related expenses, and labor unit costs in particular. While network legacy carriers have improved cost efficiency through dramatic labor cost reductions and longer stage length flying, low-cost carriers labor unit costs continue to increase as these former new entrant airlines mature.     

An Exploratory analysis of flight delay propagation in China

Delay propagation is the flight departure delay caused by the arrival delay of pre-segment flight. Chinese airline market has suffered very poor on-time performance (OTP) in recent years. It is, however, unclear whether delay propagation prevails as one major source for such problem. This study first aims to empirically quantify delay propagation in the Chinese airline market. Specifically, we shed light on heterogenous levels of delay propagations across different airports and airlines. Then, the distinct delay propagation patterns in China are also discussed and compared with other developed airline markets (e.g., the US and Europe). Our estimation is based on OTP data for over 12 million Chinese flights covering the 2015–2017 period. Specifically, it is found that 10 min arrival delay of pre-segment flight within 1 hr before the departure lead to an average of 7.49 mins delay propagation for subsequent departure flight. Arrival delay of earlier pre-segments (1–2 and 2–3 hr before the departure) leads to much less delay propagation, due to longer ground buffer. Chinese airlines arrange longer ground and flight buffer than that of the US airlines to prevent the delay propagation from accumulating along the subsequent flights in a day. Thus, unlike the US market, delay propagation is not the major reason for poor OTP in China. In addition, delay propagation is less prevailing at the Chinese hub airport. This is because China has relied on point-to-point network, which does not require sophisticated schedule coordination. And the local passengers at these Chinese hub airports have higher time value such that the Chinese airlines also try to improve OTP at these hub airports to better serve these lucrative but time-sensitive local passengers. Unlike the European LCCs, Spring Airlines, the largest low-cost carrier (LCC) in China, outperforms major full-service carriers (FSCs) in controlling delay propagation. This finding may also apply to other Northeast Asian LCCs sharing common operational characteristics as Spring Airlines. Last, we find that airlines purposely tolerate moderate departure delays of up to 15 min, which is the threshold that defines delays, no matter whether the pre-segment flight arrives late or on-time. The relevant policy and managerial implications are also discussed.     

An airline's management strategies in a competitive air transport market

Over the last decade, the demand for domestic and international flights in Korea has increased substantially. To meet the strong flight demands, several low cost carriers have begun to offer flight services. In addition, full service carriers have been motivated to establish their own subsidiary low cost carriers to maintain their market share against rival low cost carriers. This paper studies the management strategies of three kinds of airlines - full service carrier, its subsidiary low cost carrier and rival low cost carrier - based on game theory in the competitive air transport market. Each airline is assumed to act as a player and chooses strategies regarding airfare, flight frequency, and the number of operating aircrafts for specific routes while maximizing its own profits. Demand leakages between the airlines are considered in the flight demand function according to the selected strategies of all airlines. Through various game situations reflecting realistic features, this study provides managerial insights that can be applied in the competitive air transport market.     

Effects of cargo types and load efficiency on airline cargo revenues

Numerous factors affect air cargo revenue management. Air cargo companies base their cargo charges on whichever is the greater of gross weight or volumetric weight. We developed a cargo consolidation model based on air cargo characteristics, and investigated the effect of cargo density, the Density Ratio of Heavy cargo to Light cargo (DRHL), and the percentage of small cargo on the chargeable weights and revenues of airlines. The empirical results show that a higher DRHL indicates greater chargeable weight, and that as the DRHL climbs to a certain level, the extent of chargeable cargo weights tends to stabilize gradually. The closer the cargo density approaches the most suitable loading density for a flight, the greater the chargeable weight is. A higher proportion of small cargo loaded on an aircraft means higher airline revenue. Our results can effectively combine types of air cargo to increase loading rates and revenues for airlines.     

Statistical characterization of deviations from planned flight trajectories in air traffic management

Understanding the relation between planned and realized flight trajectories and the determinants of flight deviations is of great importance in air traffic management. In this paper we perform an in-depth investigation of the statistical properties of planned and realized air traffic on the German airspace during a 28 day periods, corresponding to an AIRAC cycle. We find that realized trajectories are on average shorter than planned ones and this effect is stronger during night-time than day-time. Flights are more frequently deviated close to the departure airport and at a relatively large angle-to-destination. Moreover, the probability of a deviation is higher in low traffic phases. All these evidences indicate that deviations are mostly used by controllers to give directs to flights when traffic conditions allow it. Finally we introduce a new metric, termed di-fork, which is able to characterize navigation points according to the likelihood that a deviation occurs there. Di-fork allows to identify in a statistically rigorous way navigation point pairs where deviations are more (less) frequent than expected under a null hypothesis of randomness that takes into account the heterogeneity of the navigation points. Such pairs can therefore be seen as sources of flexibility (stability) of controllers traffic management while conjugating safety and efficiency.     

User-Driven Prioritisation Process (UDPP) from advanced experimental to pre-operational validation environment

When the European Air Traffic Management Network (EATMN) approaches its capacity limits at certain airports, generating increasingly costly delays to flights and for passengers, reducing the impacts on airlines and passengers will be essential. There are two ways to address such increases in delay and costs. One is to strive to augment the capacity to reduce both delays and costs. The other one, adopted in this paper, is to reduce the impact of the delay on airlines and passengers.The User Driven Prioritisation Process (UDPP) provides airlines with additional flexibility in planning within constrained situations where delays are allocated, beyond the current slot swapping process already implemented by the EUROCONTROL Network Manager (NM).The paper presents recent validation results. It summarizes earlier results in a simplified EATMN with one constraint and several AUs showing that UDPP could reduce the impact of that delays on AUs' direct operational costs by 58% on average, and improves passengers’ connections. The paper then describes a parallel validation activity including several trials with SWISS. It focuses on the most recent validation results in a pre-operational environment close to SWISS Operations Control Centre (OCC). The results revealed overall operational benefit up to 65% improvement for the airline; and an initial impact assessment on the EATMN -although limited to one UDPP in the EATMN and one airline using it- shows promising results for the on-going integration closer to operations.While limited due to the simplified network context, these results are encouraging to undertake more complete network impact studies as well as to move forward to environments that are more realistic, bridging towards deployment.     

Perspectives for a future high-speed train in the Swedish domestic travel market

Gröna tåget (the Green Train) is a research and development project with the aim to develop a high-speed tilting train concept for the Swedish and Nordic markets. Competition with other modes needs to be evaluated, especially as regards travelling times and fares, with special attention paid to domestic airlines.For new trains, gains in travelling times and lower operational costs can be expected. Model calculations of operational costs for domestic air stages and high-speed trains, respectively, show that high-speed trains have lower costs per available seat kilometer. Train operators can meet competition with fares from coaches and air carriers provided they introduce yield management. The primary competition is about travelling times. Gröna tåget would increase the train’s attractiveness and win over some travel from airlines.     

Temporal configurations of European airline networks

The deregulation of the US domestic airline industry resulted in the reconfiguration of airline networks into hub-and-spoke systems. In contrast to the US airlines, airlines in Europe already operated spatially concentrated networks long before deregulation. This concentration at the national home-base was the outcome of bilateral traffic rights designated to the national carrier. With a few exemptions, however, most of these star-shaped networks were not coordinated in time. Transfer opportunities at most national airports only existed by accident. Only airports that were operated as gateways to Europe provided planned connectivity between intercontinental flights and European feeder services. The deregulation of the EU market stimulated a second phase of airline network restructuring. European airlines concentrated their networks by adopting or intensifying wave-system structures (‘banks’ to use the US term) in their flight schedules. This paper investigates these post-deregulation temporal concentrations in European aviation networks. The development and configuration of wave-system structures at European airline hubs is analyzed as well as the resulting transfer opportunities during the 1990s. It is found that a temporal concentration trend exists among European airlines with deregulation resulting in the adoption or intensification of wave-system structures by airlines. These wave-system structures, as well as overall traffic growth, have significantly stimulated the number of indirect hub connections. Airline hubs with wave-system structures generally perform better because of the increased indirect connectivity given the number of direct connections.     

Network-wide assessment of ATM mechanisms using an agent-based model

This paper presents results from the SESAR ER3 Domino project. Three mechanisms are assessed at the ECAC-wide level: 4D trajectory adjustments (a combination of actively waiting for connecting passengers and dynamic cost indexing), flight prioritisation (enabling ATFM slot swapping at arrival regulations), and flight arrival coordination (where flights are sequenced in extended arrival managers based on an advanced cost-driven optimisation). Classical and new metrics, designed to capture network effects, are used to analyse the results of a micro-level agent-based model. A scenario with congestion at three hubs is used to assess the 4D trajectory adjustment and the flight prioritisation mechanisms. Two different scopes for the extended arrival manager are modelled to analyse the impact of the flight arrival coordination mechanism. Results show that the 4D trajectory adjustments mechanism succeeds in reducing costs and delays for connecting passengers. A trade-off between the interests of the airlines in reducing costs and those of non-connecting passengers emerges, although passengers benefit overall from the mechanism. Flight prioritisation is found to have no significant effects at the network level, as it is applied to a small number of flights. Advanced flight arrival coordination, as implemented, increases delays and costs in the system. The arrival manager optimises the arrival sequence of all flights within its scope but does not consider flight uncertainties, thus leading to sub-optimal actions.     

Identifying airline cost economies: An econometric analysis of the factors affecting aircraft operating costs

This paper provides the results of an econometric analysis of the influences of airline characteristics on the average operating costs per aircraft movement. The analysis combines a comprehensive selection of airline-output variables, airline-fleet variables, and airline-market variables. The results confirm the existence of economies of density, economies of load factor, economies of aircraft utilisation and economies of aircraft size. The paper does not provide evidence of economies of scale, economies of stage length or economies of fleet commonality. Furthermore, airlines that additionally operate full freighters, airlines that are members of a worldwide alliance and airlines that operate a multi-hub system face higher average operating costs per aircraft movement. Surprisingly, the regression results demonstrate that airlines that use newer aircraft have higher average operating costs per aircraft movement, suggesting that ownership costs (depreciation and leasing costs) of new aircraft outweigh the increasing maintenance costs of old aircraft. Finally, the results show that airlines that have a dominant position at their hubs or bases have higher operating costs per aircraft movement, implying that the absence of serious competitive pressure enables airlines to charge higher ticket prices and, with that, leads to a limited focus on cost savings.     

Advance purchase behaviors of air passengers: A continuous logit model

Modeling the advance purchase behaviors of air passengers is essential when airlines develop revenue management strategies. Therefore, this study empirically investigates advance purchase behaviors based on the air ticket transaction data by using a continuous logit model. The estimation results show that advance purchase behaviors are significantly affected by price, price uncertainty, time of day (morning, afternoon and evening flight), days of week (flight on Friday), months of year (peak or off-peak seasons), and consecutive holiday. Accordingly, different pricing strategies should be used for different flights to maximize revenue.     

Frequency and aircraft size dynamics in a concentrated growth market: The case of the Chinese domestic market

Despite the explosive growth of the Chinese aviation sector and the major industry reforms undertaken in recent decades, the Chinese domestic market remains highly concentrated with a significant element of regulation and governmental control in areas such as market entry and airline fleet planning. In this study, we investigate the frequency strategies and aircraft choices of airlines operating in this concentrated growth market. Our empirical investigation suggests that airlines mainly accommodate rapid traffic growth by flying more frequently, although increased aircraft size also contributes to market expansion. We also find a negative relationship between market concentration and flight frequency. Due to the more balanced market structure resulting from mergers among leading airlines since 2002, there has been a moderate reduction in market concentration at route level, contributing to a 3.7% increase in traffic volume from 2002 to 2008. The results of our study suggest that Chinese travelers have yet to fully enjoy the benefits of market liberalization, and airports should prioritize increasing capacity related to aircraft movements over the accommodation of larger aircraft.     

An investigation of fatigue issues on different flight operations

The influence of various kinds of flight operations on pilot fatigue remains a chronic problem which has a bearing on flight safety. In this study we sampled flight crews from six airlines in Taiwan, asking them to report on their perceptions of both physical and mental fatigue, before and after flight duty. The data were then analyzed with paired t-test and ANOVA. Our research results confirm findings obtained in other studies, namely, that perceived fatigue levels increase after flight duty, with that of oceanic crews being greater than that of crews serving either regional or short-haul operations. A majority of the pilots surveyed reported feeling fatigued or even nodding-off during long-distance flights, and consequently were in favor of a program of scheduled cockpit napping. While these findings are preliminary, they offer valuable information to aviation regulators and airlines regarding the assigning of consecutively scheduled flights to the same aircrews.     

Drivers of airline loyalty: Evidence from the business travelers in China

This paper examines the key factors that determine business traveler loyalty toward full-service airlines in China. Based on literature review and panel interview, ten airline attributes under three categories were derived: (a) operational factors: safety, punctuality, and aircraft; (b) competitive factors: frequency of flights, schedule, frequent flyer program, ticket price, and reputation; and (c) attractive factors: in flight food & drinks and in flight staff service. We surveyed 2000 Chinese business travelers on domestic flights, obtaining 462 usable questionnaires. Hierarchical regression analysis reveals that reputation, in-flight service, frequent flyer program, and aircraft have the greatest influence in driving airline loyalty.     

Impact of operational performance on air carrier cost structure: Evidence from US airlines

The impact of operational performance on airline cost structure is empirically investigated using an aggregate, statistical cost estimation approach. Two distinct sets of operational performance metrics are developed and incorporated into the airline cost models as arguments. Results from estimating a variety of airline cost models reveal that both delay and schedule buffer are important cost drivers. We also find that flight activity outside schedule windows increases cost, whereas flight inactivity within schedule windows does not. Using the estimated cost models, we predict the cost savings to airlines of “perfect” operational performance, obtaining an estimate in the range of $7.1–13.5 billion for 2007.