The impact on Chinese passenger airlines by including them in emission reduction schemes

Civil Aviation contributes to 2-3% of global total GHG emissions. Although it is a small share, the growth rate of aircraft emissions is faster than most industries in the world. Scientists and aircraft manufacture keen to find means to improve fuel efficiency and reduce aircraft emissions. However, technology innovation is not going to be achieved in the near future. Therefore, governments and international organisations placed their focus on policy instruments. This thesis selects China, the largest emitter in the world, as an example to study how emissions mitigation schemes could influence the airline industry. While there has been a spectacular growth in Chinese aviation in recent decades, driven by economic and population growth, limited research has focused on the consequential increase in carbon dioxide emissions from the Chinese aviation industry, which has grown on average by 12% per annum since 1986. Therefore, this research firstly examined historical drivers pushing aviation sector to grow; and then develops a range of empirical models of future aviation growth to explore the cost impact of emission abatement instruments on the growth and competitiveness of the Chinese aviation industry. By using flights between EEA countries and China as a case study, the thesis develops a more detailed region-paired demand model to project future growth of international aviation; and also compared discrete choice analysis with the market share model and myopic game theory to examine the impact on airline competition due to mitigation schemes. There are significant policy challenges in developing mitigation schemes for international aviation, which are explored in this thesis as well. The empirical analysis of the thesis provides a better understanding to policymakers about how to cooperate with developing countries and developed countries together in dealing with the issue of high volumes of aircraft emission

A multiscale strategy for fouling prediction and mitigation in gas turbines

Gas turbines are one of the primary sources of power for both aerospace and land-based applications. Precisely for this reason, they are often forced to operate in harsh environmental conditions, which involve the occurrence of particle ingestion by the engine. The main implications of this problem are often underestimated. The particulate in the airflow ingested by the machine can deposit or erode its internal surfaces, and lead to the variation of their aerodynamic geometry, entailing performance degradation and, possibly, a reduction in engine life. This issue affects the compressor and the turbine section and can occur for either land-based or aeronautical turbines. For the former, the problem can be mitigated (but not eliminated) by installing filtration systems. For what concern the aerospace field, filtration systems cannot be used. Volcanic eruptions and sand dust storms can send particulate to aircraft cruising altitudes. Also, aircraft operating in remote locations or low altitudes can be subjected to particle ingestion, especially in desert environments. The aim of this work is to propose different methodologies capable to mitigate the effects of fouling or predicting the performance degradation that it generates. For this purpose, both hot and cold engine sections are considered. Concerning the turbine section, new design guidelines are presented. This is because, for this specific component, the time scales of failure events due to hot deposition can be of the order of minutes, which makes any predictive model inapplicable. In this respect, design optimization techniques were applied to find the best HPT vane geometry that is less sensitive to the fouling phenomena. After that, machine learning methods were adopted to obtain a design map that can be useful in the first steps of the design phase. Moreover, after a numerical uncertainty quantification analysis, it was demonstrated that a deterministic optimization is not sufficient to face highly aleatory phenomena such as fouling. This suggests the use of robust or aggressive design techniques to front this issue. On the other hand, with respect to the compressor section, the research was mainly focused on the building of a predictive maintenance tool. This is because the time scales of failure events due to cold deposition are longer than the ones for the hot section, hence the main challenge for this component is the optimization of the washing schedule. As reported in the previous sections, there are several studies in the literature focused on this issue, but almost all of them are data-based instead of physics-based. The innovative strategy proposed here is a mixture between physics-based and data-based methodologies. In particular, a reduced-order model has been developed to predict the behaviour of the whole engine as the degradation proceeds. For this purpose, a gas path code that uses the components’ characteristic maps has been created to simulate the gas turbine. A map variation technique has been used to take into account the fouling effects on each engine component. Particularly, fouling coefficients as a function of the engine architecture, its operating conditions, and the contaminant characteristics have been created. For this purpose, both experimental and computational results have been used. Specifically for the latter, efforts have been done to develop a new numerical deposition/detachment model.Le turbine a gas sono una delle pricipali fonti di energia, sia per applicazioni aeronautiche che terrestri. Proprio per questa ragione, esse sono spesso costrette ad operare in ambienti non propriamente puliti, il che comporta l’ingestione di contaminanti solidi da parte del motore. Le principali implicazioni di questo problema sono spesso sottovalutate. Le particelle solide presenti nel flusso d’aria che il motore ingerisce durante il suo funzionamento possono depositarsi o erodere le superfici interne della macchina, e portare a variazioni alla sua aerodinamica, quindi a degrado di performance e, molto probabilmente, alla diminuzione della sua vita utile. Questo problema aflligge sia la parte del compressore che la parte della turbina, e si manifesta sia in applicazioni terrestri che aeronautiche. Per quanto riguarda la prima, la questione può essere mitigata (ma non eliminata) dall’installazione di sistemi di filtraggio all’ingresso della macchina. Per le applicazioni aeronautiche invece, i sistemi di filtraggio non possono essere utilizzati. Questo implica che il particolato presente ad alte quote, magari grazie ad eventi catastrofici quali eruzioni vulcaniche, o a basse quote, quindi ambienti deseritic, entra liberamente nella turbina a gas. Lo scopo principale di questo lavoro di tesi, è quello di proporre differenti metodologieallo scopo di mitigare gli effetti dello sporcamento o predirre il degrado che esso comporta nelle turbine a gas. Per questo scopo, sia la parte del compressore che quella della turbina sono state prese in considerazione. Per quanto riguarda la parte turbina, saranno presentate nuove guide progettuali volte al trovare la geometria che sia meno sensibile possibile al problema dello sporcamento. Dopo di ciò, i risultati ottenuti verranno trattati tramite tecniche di machine learning, ottenendo una mappa di progetto che potrà essere utile nelle prime fasi della progettazione di questi componenti. Inoltre, essendo l’analisi fin qui condotta di tipo deterministico, un’analisi delle principali fonti di incertezza verrà eseguita con l’utilizzo di tecniche derivanti dall’uncertainty quantification. Questo dimostrerà che l’analisi deterministica è troppo semplificativa, e che sarebbe opportuno spingersi verso una progettazione robusta per affrontare questa tipologia di problemi. D’altro canto, per quanto concerne la parte compressore, la ricerca è stata incentrata principalmente sulla costruzione di uno strumento predittivo, questo perchè la scala temporale del degrado dovuto alla deposizione a "freddo" è molto più dilatata rispetto a quella della sezione "calda". La trategia proposta in questo lavoro di tesi è un’insieme di modelli fisici e data-driven. In particolare, si è sviluppato un modello ad ordine ridotto per la previsione del comportamento del motore soggetto a degrado dovuto all’ingestione di particolato, durante un’intera missione aerea. Per farlo, si è generato un codice cosiddetto gas-path, che modella i singoli componenti della macchina attraverso le loro mappe caratteristiche. Quest’ultime vengono modificate, a seguito della deposizione, attraverso opportuni coefficienti di degrado. Tali coefficienti devono essere adeguatamente stimati per avere una corretta previsione degli eventi, e per fare ciò verrà proposta una strategia che comporta l’utilizzo sia di metodi sperimentali che computazionali, per la generazione di un algoritmo che avrà lo scopo di fornire come output questi coefficienti

Modelling Emissions Reduction Strategies for Passenger Air Transport

This dissertation aims to evaluate the potential for and the effectiveness of two strategies that could reduce carbon dioxide (CO2) emissions from passenger aviation. The two strategies consist of market-based measures (MBMs) and the substitution of high-speed rail (HSR) for air transport. To assess the first mitigation strategy an econometric, itinerary-based airfare model, which explicitly captures airline operating costs, is developed and estimated for different world regions. Based on the estimated cost pass-through elasticities, the impact of a carbon tax is tested for the European and Asia-Pacific markets. Because of the higher cost pass-through elasticity in the Asia-Pacific market, a carbon tax would lead to higher airfares, lower demand, and thus greater emissions reductions in the Asia-Pacific compared to the European market. For the second mitigation strategy, i.e. the HSR substitution for air transport, this dissertation takes China’s transportation network as a case study. In a first step, an empirical study explores how airline supply has already been affected by the introduction of HSR since 2008. The results show that the HSR substitution has led to operational CO2 emissions savings from aviation in the order of 6.52-7.44 million tonnes over the period 2009-2015, depending on assumptions on the electricity intensity of Chinese HSR trains. In a second step, the dissertation explores how the enhanced introduction of HSR may affect future aviation CO2 emissions. To accomplish this objective, the future demand for inter-city high-speed transportation between 2016 and 2050 and the mode shares of HSR and air travel are estimated with an econometric model. The projected aviation demand under the planned 2025 HSR network is then compared against the demand under the 2015 HSR network. The marginal net savings of lifecycle CO2 emissions resulting from the HSR substitution are calculated from the “avoided” emissions in aviation and the additional emissions generated from transporting the diverted demand by HSR. The results show that, if China continues decarbonizing its power generation sector and achieves zero-carbon power generation in 2050, the cumulative marginal net savings of CO2 emissions could be at 736-960 million tonnes, depending on assumptions on China’s future population, GDP per capita, and jet fuel prices. The annual average of this amount between 2016 and 2050 are equivalent to 39-50% of the 53.8 million tonnes CO2 emissions from domestic aviation in 2015

Valuation of aviation externalities: a case study in Bangkok, Thailand

Aircraft noise, for the first time in Thailand, has gained public attention as a significant environmental issue since Bangkok s Suvarnabhumi Airport opened in 2006. Residential areas around the airport are expanding rapidly while local residents are protesting about the noise from the new airport which suggests a tension between economic benefits and environmental problems at the airport. This thesis sets out to obtain valuation of aviation externalities at Suvarnabhumi airport using the stated choice method. It is the first study to obtain and compare valuations from perspectives of the polluters (Thai air passengers) and the polluted (residents) at the same airport. Furthermore, this is the first study to obtain a valuation of local impacts from aircraft operations and from air passengers. It starts by investigating perceptions and awareness of the benefits and costs of aviation activities among Suvarnabhumi s residents and passengers using focus groups and questionnaires. It then employs the stated choice method to elicit willingness-to-pay (WTP) and willingness-to-accept (WTA) values of aviation externalities. The results found that the perceived environmental problems at Suvarnabhumi airport are in line with the literature mainly involving aircraft noise and its effects. This study also found that the development of the airport and surrounding area, while creating business and employment opportunities, has also created traffic and flooding problems. In terms of air pollution from aircraft, residents concerns are confined to local impacts from aircraft. Thai air passengers were found to be more concerned with engine pollution than noise. These findings were reflected in the values obtained. Two stated choice designs were used to elicit values. The first rerouted the aircraft flight path away from residents homes thus reducing aircraft noise and pollution in the area. This design also included travel time to place of work or to the shops. The rerouting attribute was not statistically significant. However, the travel time attribute reveals that residents were willing to accept 14.23 baht a month to have their travel time to work or shopping increased by 1%. The second design was used to obtain and compare values between Suvarnabhumi s residents and air passengers. In this design, attributes for aircraft noise, local air pollution and carbon emissions were included. Residents willingness to pay to reduce aircraft noise by 1% is 104.76 baht/year whereas passengers are willing to pay less, at 70.63 baht per year. Air passengers place a higher value on local air pollution than the residents. Passengers are willing to pay 97.72 baht to reduce local pollution by 1% per year, whereas residents willingness to pay is 45.36 baht. Lastly, passengers WTP to offset carbon is 473.26 baht per flight, whereas residents carbon offset coefficient is not statistically significant. The obtained values are well within the range of existing studies on aircraft noise and carbon emission valuations. Findings from this study suggest that current mitigation measures at Suvarnabhumi airport are still inadequate. There are areas where the situation is likely to get worse given the rapid growth in aviation activities and urban development at the airport. The values from this study may be used to help form the basis of fairer and more transparent compensation system alongside an operational mitigation policy to address aviation impacts. On the passenger side, the stated willingness-to-pay to reduce the impact gives an opportunity for the Thai aviation industry to promote an environmentally friendly behaviour among the travelling public

European struggles and American resistance: inclusion of aviation into the EU ETS

This research examines the process of inclusion of aviation into the European Union Emissions Trading System (EU ETS). The thesis investigates an environmentally-recalcitrant community (aviation industry) and its attempts to suspend the application of the EU ETS on the sector. It focuses on the decision-making processes at the European Union (EU) level and juxtaposes the European policy-making with the resistance to inclusion shown in the political system of the United States (US). More specifically, it seeks to understand the factors affecting the effectiveness of efforts to forge effective international environmental policy, especially those driven by the EU in the context of climate change. Theoretically, this research draws on three theories: Multi-level governance, Policy Network Analysis and Interpretive Policy Analysis. These theories are advanced by considering the meaning-making activities pursued by the stakeholders and discursive aspects of the process analysed. Empirically the thesis is informed by a series of semi-structured interviews conducted in Washington, DC in 2013 and in Brussels, Belgium in 2014, policy documents, and media content analysis. The thesis concludes that the climate ambitions of the (EU) may instigate international resistance leading to deterioration of relations with international partners. The thesis proves too that the conflict in the EU ETS case is related to the construction of interests both within the EU and vis à vis its international partners. The research contributes also to understanding the internal proceedings of the European Commission by showing discrepancies in decision-making between the Directorate Generals. It shows that the locus of policy making can be changed towards more non-material venues. Finally, the results show that aviation enjoys a particularly powerful position among other businesses both in the EU and in the US and is able to shape policy-making at the national and international level

Simulating airline operational responses to environmental constraints

This dissertation describes a model that predicts airline flight network, frequency and fleet changes in response to policy measures that aim to reduce the environmental impact of aviation. Such airline operational responses to policy measures are not considered by existing integrated aviation-environment modelling tools. By not modelling these effects the capability of the air transport system to adjust under changing conditions is neglected, resulting in the forecasting of potentially misleading system and local responses to constraints. The model developed follows the overriding principle of airline strategic decision making, i.e., airline profit maximisation within a competitive environment. It consists of several components describing different aspects of the air transport system, including passenger demand forecasting, flight delay modelling, estimation of airline costs and airfares, and network optimisation. These components are integrated into a framework that allows the relationships between fares, passenger demand, infrastructure capacity constraints, flight delays, flight frequencies, and the flight network to be simulated. Airline competition is modeled by simulating a strategic game between airlines competing for market share, each of which maximizes its own profit. The model is validated by reproducing historical passenger flows and flight frequencies for a network of 22 airports serving 14 of the largest cities in the United States, using 2005 population, per capita income and airport capacities as inputs. The estimated passenger flows and flight frequencies compare well to observed data for the same network (the R2 value comparing flight segment frequencies is 0.62). After validation, the model is applied to simulate traffic growth and carbon dioxide and nitrogen oxide emissions within the same network from 2005 to 2030 under a series of scenarios. These scenarios investigate airline responses to (i) airport capacity constraints, (ii) regional increases in costs in the form of landing fees, and (iii) major reductions in aircraft fuel burn, as would be achieved through the introduction of radically new technology such as a blended wing body aircraft or advanced open rotor engines. The simulation results indicate that, while airport capacity constraints may have significant system-wide effects, they are the result of local airport effects which are much greater. In particular, airport capacity constraints can have a significant impact on flight delays, passenger demand, aircraft operations, and emissions, especially at congested hub airports. If capacity is available at other airports, capacity constraints may also induce changes in the flight network, including changes in the distribution of connecting traffic between hubs and the distribution of true origin-ultimate destination traffic between airports in multi-airport systems. Airport capacity constraints are less likely to induce any significant increase in the size of aircraft operated, however, because of frequency competition effects, which maintain high flight frequencies despite reductions in demand in response to increased flight delays. The simulation results also indicate that, if sufficiently large, regional increases in landing fees may induce significant reductions in aircraft operations by increasing average aircraft size and inducing a shift in connecting traffic away from the region. The simulation results also indicate that the introduction of radically new technology that reduces aircraft fuel burn may have only limited impact on reducing system CO2 emissions, and only in the case where the new technology can be taken up by the majority of the fleet. The reason for this is that the reduced operating costs of the new technology may result in an increase in frequency competition and thus aircraft operations. In conclusion, the modelling of airline operational responses to environmental constraints is important when studying both the system and local effects of environmental policy measures, because it captures the capability of the air transport system to adjust under changing conditions.This work was supported by the Engineering and Physical Sciences Research Council and the Natural Environment Research Council [grant number EP/D060001/1]

Airports and territory: Emergence of a new strategic actor in the air transport system

This thesis deals with the emergence of the airport as a new strategic actor in the air transport system which has undergone profound changes since its liberalisation and within which the airport turned out to be a major player. Considering the airport as an actor in the air transport system, even if it is affected by its environment in a large sense, this work proposes a contribution to current discussion about airport economics. This contribution refers to two levels: an analysis of the European airport business within which the airport emerges as a full player and an analysis of the link between airport strategy and the spatial and territorial context into which the airport is embedded. Based on the differentiation of airport strategies according to the airports’ commitment to certain market segments, the analysis of the spatial and territorial context into which the airports are embedded showed its influence on the development of airports but confirmed also that the latter is not automatic but subject to the dynamics arising from the interactions between the different actors. The emergence of the airport as a new strategic player in the air transport system places the emphasis on the complex relation between airport and territory which is reflected in a number of issues connected with the airport activity.Diese Doktorarbeit beschäftigt sich mit dem Flughafen als einem neuen strategischen Akteur im Luftverkehrssystem, welches seit seiner Liberalisierung von weitreichenden Veränderungen erfasst wurde, und in dem der Flughafen sich zum wichtigen Teilnehmer entwickelt hat. Durch die Betrachtung des Flughafens als Akteur des Luftverkehrs, auch wenn er dem Einfluss seiner Umwelt im weitesten Sinne unterliegt, möchte diese Arbeit einen Beitrag zur gegenwärtigen Diskussion zum Thema Flughäfen in zweifacher Hinsicht leisten: Eine Analyse des europäischen Luftverkehrssystems, in dem der Flughafen als ganzheitlicher Partner deutlich wird sowie eine detaillierte Untersuchung der Verbindung zwischen Flughafenstrategien und der Verankerung des Flughafens in Raum und Territorium. Ausgehend von der Differenzierung der Flughafenstrategien, die durch die Spezialisierung auf ein oder mehrere Marktsegmente ihren Ausdruck findet, lässt die Analyse des räumlichen und territorialen Kontexts, in dem der Flughafen verankert ist, dessen Einfluss auf die Entwicklung des Flughafens deutlich werden, aber bestätigt auch, dass letzere nicht ein automatisches Ergebnis ist, sondern von den Interaktionen der verschiedenen Akteure abhängt. Die Entstehung des Flughafens als neuer strategischer Akteur im Luftverkehrssystem betont die komplexen Beziehungen zwischen Flughafen und Territorium, die sich in einer Reihe von Aspekten widerspiegeln, die in dieser Arbeit diskutiert werden.Cette thèse de doctorat porte sur l’émergence de l’aéroport comme nouvel acteur stratégique dans le système de transport aérien qui a connu de vastes changements depuis sa libéralisation et au sein duquel l’aéroport est devenu un acteur majeur. En considérant l’aéroport comme acteur du transport aérien, bien qu’il soit affecté par son environnement au sens large, ce travail propose une contribution à la discussion récente sur la question des aéroports. Cette contribution se réfère à deux niveaux : une analyse du système de transport aérien européen dans lequel l’aéroport émerge comme partenaire à part entière et une analyse détaillée du lien entre stratégies aéroportuaires et l’ancrage de l’aéroport dans l’espace et dans le territoire. En partant de la différentiation des stratégies aéroportuaires avec des aéroports qui se spécialisent dans un certain ou plusieurs segments de marché, l’analyse du contexte spatial et territorial, dans lequel les aéroports sont ancrés, a révélé son influence sur le développement des aéroports mais a confirmé aussi que ce dernier n’est pas un résultat mécanique mais est soumis aux dynamiques résultant du jeu d’acteurs. L’émergence de l’aéroport comme nouvel acteur stratégique dans le système de transport aérien met en lumière les rapports complexes entre aéroports et territoire qui se reflètent dans un certain nombre d’aspects discutés dans ce travail

Unmet goals of tracking: within-track heterogeneity of students' expectations for

Educational systems are often characterized by some form(s) of ability grouping, like tracking. Although substantial variation in the implementation of these practices exists, it is always the aim to improve teaching efficiency by creating homogeneous groups of students in terms of capabilities and performances as well as expected pathways. If students’ expected pathways (university, graduate school, or working) are in line with the goals of tracking, one might presume that these expectations are rather homogeneous within tracks and heterogeneous between tracks. In Flanders (the northern region of Belgium), the educational system consists of four tracks. Many students start out in the most prestigious, academic track. If they fail to gain the necessary credentials, they move to the less esteemed technical and vocational tracks. Therefore, the educational system has been called a 'cascade system'. We presume that this cascade system creates homogeneous expectations in the academic track, though heterogeneous expectations in the technical and vocational tracks. We use data from the International Study of City Youth (ISCY), gathered during the 2013-2014 school year from 2354 pupils of the tenth grade across 30 secondary schools in the city of Ghent, Flanders. Preliminary results suggest that the technical and vocational tracks show more heterogeneity in student’s expectations than the academic track. If tracking does not fulfill the desired goals in some tracks, tracking practices should be questioned as tracking occurs along social and ethnic lines, causing social inequality

Third International Symposium on Space Mission Operations and Ground Data Systems, part 1

Under the theme of 'Opportunities in Ground Data Systems for High Efficiency Operations of Space Missions,' the SpaceOps '94 symposium included presentations of more than 150 technical papers spanning five topic areas: Mission Management, Operations, Data Management, System Development, and Systems Engineering. The papers focus on improvements in the efficiency, effectiveness, productivity, and quality of data acquisition, ground systems, and mission operations. New technology, techniques, methods, and human systems are discussed. Accomplishments are also reported in the application of information systems to improve data retrieval, reporting, and archiving; the management of human factors; the use of telescience and teleoperations; and the design and implementation of logistics support for mission operations