The role of turboprops in China’s growing aviation system

The Chinese aviation system is in a period of rapid growth, with significant growth in second tier and emerging cities. Lower density cities could be well served by regional aircraft, either regional jets or turboprops, which offer different qualities and a different future for Chinese aviation. Turboprops offer a high level of fuel efficiency compared with regional jets which may improve the cost economics for carriers and reduce the air quality and climate impacts of a growing aviation system in a region where air quality and greenhouse gas emissions are a serious concern. However, regional jets are known for their superior quality of service and faster travel speeds. We begin with a spatial analysis of existing Chinese short-haul aviation networks and find that turboprops are deployed in limited number and are dispersed throughout the country. Their limited use, however, is not because of their cost economics. For the existing regional jet network we estimate the trade space of fuel and time for the replacement of regional jets with turboprops and find that all regional jet routes in China would generate savings if replaced with turboprops. We next establish future short-haul aviation routes between new and emerging airports and estimate the likelihood that a turboprop will be used. The finding that the most viable turboprop markets are spatially dispersed through the country validates considering turboprop investment at the state-level as a component of the established Chinese aviation sustainability initiative.     

The emission reduction potentials of First Generation Electric Aircraft (FGEA) in Finland

Under the looming climate crisis, aviation needs to find new solutions to cut its greenhouse gas emissions. One pathway towards zero emissions is the use of electric aircraft. While current battery technology will not allow for medium and long-haul flights at full capacity, on short-haul routes First Generation Electric Aircraft (FGEA) could play a significant role in the near future. Current FGEA under development could carry 9–19 passengers on distances of 400–1046 km by 2025. This study focuses on the emissions reduction potentials of FGEA in Finland. It compares the carbon dioxide equivalent (CO₂-eq) emissions and real travel times (RTT) from door-to-door of FGEA on 47 routes with existing aircraft, train and car transport modes, as well as with proposed high-speed rail (HSR) and electric vehicle implementation. The study found that replacing all existing aircraft with FGEA can clearly be recommended as it would result in a reduction of CO₂-eq emissions and RTT. Existing cars should only be replaced by FGEA on routes beyond 170 km. The replacement of existing trains by FGEA under the current energy mix is not recommended. However, once electricity could be provided from renewable energy sources exclusively, it would become feasible to replace existing trains on distances beyond 170 km and HSR beyond 400 km with FGEA.     

Next generation single-aisle aircraft – Requirements and technological solutions

In recent years, aircraft manufacturers have concentrated on developing new long-haul widebody aircraft, such as Airbus’s A380 and A350XWB and Boeing’s 787 and 747-8. The next challenge for manufacturers and suppliers is the development of new short- and medium-range single-aisle aircraft. This paper outlines how the challenges and quantified goals as developed by the Advisory Council for Aeronautics Research in its Strategic Research Agenda would influence and contribute to the improvement of the next generation of civil transport aircraft. It continues with a discussion on possible aircraft requirements from the viewpoint of an aircraft operator. Subsequently, the most important technological elements available for the next generation single-aisle aircraft are briefly characterised. Using the Council’s objectives for CO₂ emissions and noise, as an example it can be shown that a decoupling of air traffic growth and emissions/noise can be achieved.     

Fuel burn rates of commercial passenger aircraft: variations by seat configuration and stage distance

Aircraft fuel consumption is a very large component of airline costs. Fuel burn is also very important because it is highly correlated with emissions and contributes directly to transport externalities. This paper calibrates fuel burn in kilos per seat per nautical mile for aircraft using the EMEP/EEA aircraft inventory database. We then employ the model with OAG flight schedule data to evaluate fuel burn by flight routes and aircraft types at a global scale. The paper shows comparative fuel use among different distance based markets as well as among a variety of routes in the long-haul market. The results show geographical heterogeneity of fuel burn rates among a variety of routes, while controlling for seat configuration and stage distance. The paper finds that stage lengths centered on 1500–2000 NM have the lowest fuel burn rates under current technology, fleet composition, and seat configuration. These findings, together with comments on the viability of long range flights provide better understandings not only for the carbon taxation debates but also for operational efficiency of current aviation markets. The lower rates for moderate distance flights seems to favor networks without extreme links, and supports the use of a hub connection scheme.     

Analysis of the recent evolution of commercial air traffic CO2 emissions and fleet utilization in the six largest national markets of the European Union

This paper presents the results of a study performed to analyze the evolution of commercial air traffic and CO₂ emissions in the European Union, from 2010 to 2013. Data sources are the European Commission's Eurostat Air Transport Statistics (Eurostat) and EUROCONTROL flight plans database. The changes in the fuel efficiency are analyzed and the potential reasons for those changes investigated. The evolution in the airline fleet composition during the last decade is presented as one of the reasons for the improvement in fuel efficiency, measured in burnt fuel per total Revenue Tonne Kilometre (RTK), as well as the different parameters depending on the airline business model (network carriers, low cost companies, etc.) and the aircraft type.Results show a slight reduction in the traffic, both for passengers and cargo (about −0.8%), and a more important reduction in CO₂ emissions (−4.3%), thanks to an improvement in the fuel efficiency parameter (−3.5%) for the three years period. There has been a relevant change in the fleet composition in the last ten years, with the replacement of older models for more efficient ones, and a shift to larger aircraft, particularly in the regional segment. Traffic has decreased in shorter distances (internal EU traffic), but increased in more efficient long range flights (extra-EU traffic), resulting also in an improvement of the efficiency parameter as average aircraft size and stage length increases.     

Investigations on the distribution of air transport traffic and CO2 emissions within the European Union

This study analyses the structure of air traffic and its distribution among the different countries in the European Union, as well as traffic with an origin or destination in non-EU countries. Data sources are Eurostat statistics and actual flight information from EUROCONTROL. Relevant variables such as the number of flights, passengers or cargo tonnes and production indicators (RPKs) are used together with fuel consumption and CO₂ emissions data. The segmentation of air traffic in terms of distance permits an assessment of air transport competition with surface transport modes.The results show a clear concentration of traffic in the five larger countries (France, Germany, Italy, Spain and UK), in terms of RPKs. In terms of distance the segment between 500 and 1000 km in the EU, has more flights, passengers, RTKs and CO₂ emissions than larger distances. On the environmental side, the distribution of CO₂ emissions within the EU Member States is presented, together with fuel efficiency parameters. In general, a direct relationship between RPKs and CO₂ emissions is observed for all countries and all distance bands. Consideration is given to the uptake of alternative fuels. Segmenting CO₂ emissions per distance band and aircraft type reveals which flights contribute the most the overall EU CO₂ emissions. Finally, projections for future CO₂ emissions are estimated, according to three different air traffic growth and biofuel introduction scenarios.     

Air freight hubs in the FedEx system: Analysis of fuel use

This paper provides a data based analysis of FedEx air freighter activities from selected hub locations. The basic idea is that air freighters have a set of range and payload parameters and their corresponding fuel burn depends on weight and distance. Data from 2011 to 12 (FlightAware) are used for 180,000 + flights on origin, destination and aircraft type. The particular aircraft vary widely in payload, but additional parameters may be derived from industry web sites and BTS. The research uses flight activity at hubs such as Memphis and Indianapolis (among others) and computes the aggregate distance flown on specific aircraft. The linkage between the hub and aggregate fuel use (assuming that the out bound flights are allocated to the hub) will give some quantifiable measures of the costs allocated to the hub. The paper examines particular aspects of the air freight system that are especially vulnerable to a spike in the costs of aviation fuel. These observations suggest that traffic to regional air express and air freight hubs is likely to respond in complex ways to fuel costs.     

Probabilistic assessment of fleet-level noise impacts of projected technology improvements

Demand projections for civil aviation have forecast increases in operations in future decades. Increases in demand are beneficial to the growth and advancement of the aviation industry, but also come with the threat of significant increase in environmental impacts. In response, the industry is focusing on programs to develop technologies for reductions in fuel burn, NO_x emissions, and noise. While aircraft-level impacts are an obvious metric of success, it is difficult to make informed robust technology investment decisions with respect to noise without understanding the fleet-level impacts. Fleet-level predictions of noise for technology explorations are especially complicated because it is computationally expensive, highly combinatorial, and airport-specific. Recently, rapid automated airport noise models have been developed, which can be simulated using Design of Experiments (DOE). The results of these simulations are used to generate surrogate models for airport noise contour area, which can be summed to yield a fleet-level impact. These models make use of simplifying assumptions to provide estimates of airport-level noise that are substantially cheaper to compute. They can be used to perform parametric trade-off analyses in conjunction with the equivalency assumption. Equivalency asserts that environmental impacts of a technology infused aircraft can be represented by scaled operations of the baseline aircraft in the same class. This simple assumption allows for the modeling of technology and market penetration factors under the same units: operations. This research uses surrogate models in conjunction with the equivalency assumption to examine two potential technology scenarios in a target forecast year, simulating technology and market performance factors to identify vehicle classes that could have the greatest impact in reducing contour area. Results show that technology and market performance of future notional Small Single Aisle and Large Single Aisle vehicle aircraft have the highest positive correlations with potential reductions in contour area.     

The historical fuel efficiency characteristics of regional aircraft from technological, operational, and cost perspectives

To develop approaches that effectively reduce aircraft emissions, it is necessary to understand the mechanisms that have enabled historical improvements in aircraft efficiency. This paper focuses on the impact of regional aircraft on the US aviation system and examines the technological, operational and cost characteristics of turboprop (TP) and regional jet (RJ) aircraft. Regional aircraft are 40–60% less fuel efficient than their larger narrow- and wide-body counterparts, while RJs are 10–60% less fuel efficient than TPs. Fuel efficiency differences can be explained largely by differences in aircraft operations, not technology. Direct operating costs per revenue passenger kilometer are 2.5–6 times higher for regional aircraft because they operate at lower load factors and perform fewer miles over which to spread fixed costs. Further, despite incurring higher fuel costs, RJs are shown to have operating costs similar to TPs when flown over comparable stage lengths.     

Emissions trading for international aviation—an estimation of the economic impact on selected European airlines

International aviation is responsible for between 2.5% and 3% of anthropogenic carbon dioxide (CO₂) emissions that are partly held responsible for climate change. International aviation is not subject to any regulatory framework for the limitation of these emissions. From an economic point of view, the introduction of an emissions trading scheme would be an appropriate instrument to limit these emissions. This paper outlines the possibilities on how aviation could be included in existing emissions trading schemes and gives an overview on the current political discussion. It continues with an empirical estimation of the impacts on operating costs and transport demand for low cost, full service, holiday and regional airlines taking Ryanair, Lufthansa, Condor and Air Dolomiti as examples, under three different design options for an emissions trading scheme. Finally, conclusions about the impacts on intra-European and worldwide airline competition are drawn.     

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.     

Flying into the future: A scenario-based analysis of carbon emissions from China's civil aviation

Aviation emissions will significantly affect climate change with the continued growth of the air transport. This study decomposes the drivers influencing China's civil aviation carbon emissions change in the period from 1985 to 2015. Emission trends are predicted using a Monte Carlo simulation. The results show a peak and reduction in the period between 2016 and 2030. Results also show that air transportation revenue growth is associated with increasing historical carbon emissions, while rising industry energy intensity significantly hampers carbon emissions reduction. The carbon intensity (CI) reduction goals were achieved in the different scenarios before 2020, but the carbon emissions peak target before 2030 can only be achieved under the technological breakthrough scenario (TBS). The reduction of air transport growth rate and promotion of new energy technologies are two essential strategies to reduce carbon emissions in the foreseeing future.     

The cost of abatement options to reduce carbon emissions from Australian international flights

In 2012, a total of 13.1 million tonnes of carbon dioxide were emitted by 14 airlines while transporting 72 per cent of international passengers into and out of Australia in 2012. With passenger and cargo traffic growing at between five to six per cent annually from 2013 to 2033, acquiring more fuel efficient aircraft to both renew the existing fleet and to service growth has the greatest potential in reducing emissions over the next 20 years. Our analysis shows that implementing carbon dioxide emissions abatement options such as installing light weight seats, iPad electronic flight bags, winglets, washing aircraft engines and reducing the number of engines used during taxiing, all offer net financial savings when considered over 20 years. Acquiring new fuel efficient aircraft has the biggest impact on emissions reduction. Low interest loans and longer loan repayment periods may incentivise airlines to acquire more fuel efficient aircraft to service traffic growth but other complimentary incentives and penalties are required to influence airlines to replace their current fleet with more fuel efficient aircraft.     

Apportioning aviation CO2 emissions to regional administrations for monitoring and target setting

Delivering reductions in greenhouse gas emissions from the aviation sector requires support and action from all tiers of government. There has been considerable focus on the policies that can be implemented at international and national levels; however, sub-national bodies can also play an important and influential role. In order to identify what this role may be, it is important for sub-national governments to have an understanding of the size of their potential emissions responsibility. At present there is no widely accepted methodology for the apportionment of either international or domestic aviation emissions to sub-national levels. This paper assesses a number of existing consumer- and producer-based CO₂ apportionment regimes that could be used to allocate the emissions from aviation to regional and other sub-national levels. This is followed by the presentation of a new hybrid consumer–producer apportionment regime applicable to aviation. This new approach is designed to provide an emissions baseline for a region that reflects its share of responsibility for the UK’s aviation emissions as both a producer of emissions and consumer of the services provided by aviation.     

Including aviation in the European emissions trading scheme: Impacts on the industry,CO2 emissions and macroeconomic activity in the EU

In July 2008, motivated by the expected high growth of aviation and the related impacts on climate change, the European Parliament adopted a directive to include airlines in the European Emissions Trading Scheme. This paper discusses possible impacts of this inclusion on the aviation industry in terms of CO₂ emissions and the macroeconomic activity in the EU. The analysis uses the Energy–Environment–Economy Model for Europe, a dynamic simulation model to investigate impacts of the European Emissions Trading Scheme on air transport. The impacts on air transport output and the macroeconomic effects are estimated to be small. This was robust to varying the carbon price. However, air transport CO₂ emissions were expected to decrease by up to 7.4%, which is more than that estimated previously and stems mainly from the supply-side reaction of the industry.     

Policy clash: Can projected aviation growth be reconciled with the UK Government's 60% carbon-reduction target?

In 2004, the UK's aviation industry emitted an estimated 9.8 MtC; a figure that, without direct intervention, is projected to rise to 16–21 MtC by 2030 according to the UK Government. As the UK's 60% carbon-reduction target approaches, so aviation is likely to become a dominant carbon-emitting sector. This paper calculates the proportion of carbon emissions resulting from the Government's projected aviation growth in relation to a contracting carbon budget. It concludes that the Government must urgently address today's very high levels of growth in emissions within the industry, and ensure future growth can be reconciled with the Government's own carbon targets.     

CO2 emissions associated with hubbing activities in air transport: an international comparison

Hubbing is an important operational practice in air transport. Many studies have been conducted to examine the benefits and impacts of hubbing from an economic perspective. However, its impact on CO₂ emissions, especially across different air spaces, is not well understood. This paper explores the impact of hubbing activities in air transport from an environmental perspective. With a detailed methodology and data from the Greek and Hong Kong/Sanya flight information regions (FIRs), three levels of CO₂ emissions are estimated: airport-based, airspace-based and flight-based. After contrasting the CO₂ emission efficiencies of Athens International Airport (AIA) and the Hong Kong International Airport (HKIA), aircraft type and flight distance are examined to explain their emission efficiency differences. It is found that HKIA is associated with poorer CO₂ emission efficiency at the airport and airspace levels because of the larger aircraft and longer flight distance. However, when CO₂ emission efficiency at the flight level is considered, HKIA, with a higher passenger load factor, performs better. Major international hub airports should implement additional environmental measures to minimize the impact of hubbing activities on CO₂ emissions at the airport and airspace levels.     

The market development of aviation biofuel: Drivers and constraints

Aviation biofuel is technically viable and nearing the commercial stage. In the last ten years, biofuels have moved from relative obscurity to a point where certain types of fuel have become fully certified for commercial use in up to 50% blends with standard jet fuel and commercial partnerships between airlines and biofuel producers are being established. Yet despite numerous successful test flights, aviation biofuels have yet to become widely commercialised. Drawing on the findings of in-depth interviews with leading global aviation biofuel stakeholders undertaken between October and December 2011, this paper identifies and examines the perceived factors that are affecting the market development of biofuels for aviation. The paper illustrates that market development is being driven by the combined effects of rising jet fuel prices, the potential future impact of emissions legislation and concerns about fuel (in)security. However, commercialisation is being constrained by high production costs, limited availability of suitable feedstocks, uncertainty surrounding the definition of the sustainability criteria, and a perceived lack of both national and international political and policy support for aviation biofuel. The implications of these findings for commercial aviation and the future development of global market for aviation biofuel market are discussed.     

Including aviation emissions in the EU ETS: Much ado about nothing? A review

The European Community, motivated by the rapid growth of the aviation industry and related impacts on climate change, has decided to include aviation in the European Emissions Trading Scheme (EU ETS). Mitigation policies such as the EU ETS are considered to be necessary in order to change travel behaviour and induce operational and technological changes in the aviation industry that will result in lower environmental impacts. This paper reviews the available impact assessments of the proposed emissions trading scheme for airlines published between 2005 and 2009. It analyses the methods used and finds that the models used are often over-simplified, omitting important variables or that the reliability and robustness of the modelling results are reduced by linking models that are based on different assumptions. The paper also summarises the possible environmental (CO₂ emissions) and economic (air fares, demand for airline services, supply of airline services, competitiveness, GDP, carbon price) impacts in the studies reviewed for the year 2020. Overall, the effects are found to be small: for example, CO₂ emissions are expected to decline by a maximum of 3.8% and the maximum impact on GDP in the EU was found to be ?0.002%. The reasons for these insignificant impacts are analysed in this paper; it is also found that there are some positive aspects of including aviation in the EU ETS.     

Airlines’ competition in aircraft size and service frequency in duopoly markets

We are interested in how airlines make decisions on aircraft size and service frequency in a competitive environment. We apply three game-theoretic models to analyze airlines’ choices in duopoly markets: one short-haul market and one long-haul market. We study how airlines’ choices in a competitive environment may vary with flight distance, and also do sensitivity analysis to explore how the equilibrium results may change when air travel demand is higher, as it may happen in the future.Our research considers the competition factor in airlines’ decisions on both aircraft size and service frequency, and the impact of these decisions on both the cost and demand sides of airlines’ business. Different from previous studies, our research is based on cost, market share and demand models derived from empirical studies.