Sustainable Aviation Research Articles

Noise in sustainable transformation of aviation

Rising awareness of aviation noise's health and annoyance impacts does not coincide with the industry's sustainable transition which is primarily driven by climate change. While electrification and sustainable fuels are seen as solutions, current strategies often encourage aviation sector growth including airport and traffic expansion. National initiatives aim to accelerate aviation's sustainable transformation, aligning with increased transportation accessibility and mobility goals. There is a push for directives for electric aviation, drones, and urban air mobility (UAM). Local health and annoyance, however, are overshadowed by the pretense of the global focus. Increased noise is anticipated with projected increases in air travel and added noise from electric and drone aircraft! This paper integrates noise and annoyance considerations into sustainable aviation transformation. A system analysis, using soft system methodologies, reveals comprehensive socio-technical perspectives from aviation, urban planning, citizens, and regulation. Findings indicate future noise challenges and unfavorable conditions for noise reduction innovations. The study advocates for society-wide strategies to manage aviation noise and annoyance, emphasizing recommendations like careful design, operational considerations, noise simulations, and democratic community involvement in implementation. These insights anticipate a surge in noise-related complaints and opposition. This paper is of interest also for future aviation developers.

Gas exchange optimization in aircraft engines using sustainable aviation fuel: A design of experiment and genetic algorithm approach

The poppet valves two-stroke (PV2S) aircraft engine fueled with sustainable aviation fuel is a promising option for general aviation and unmanned aerial vehicle propulsion due to its high power-to-weight ratio, uniform torque output, and flexible valve timings. However, its high-altitude gas exchange performance remains unexplored, presenting new opportunities for optimization through artificial intelligence (AI) technology. This study uses validated 1D + 3D models to evaluate the high-altitude gas exchange performance of PV2S aircraft engines. The valve timings of the PV2S engine exhibit considerable flexibility, thus the Latin hypercube design of experiments (DoE) methodology is employed to fit a response surface model. A genetic algorithm (GA) is applied to iteratively optimize valve timings for varying altitudes. The optimization process reveals that increasing the intake duration while decreasing the exhaust duration and valve overlap angles can significantly enhance high-altitude gas exchange performance. The optimal valve overlap angle emerged as 93 °CA at sea level and 82 °CA at 4000 m altitude. The effects of operating parameters, including engine speed, load, and exhaust back pressure, on the gas exchange process at varying altitudes are further investigated. The higher engine speed increases trapping efficiency but decreases the delivery ratio and charging efficiency at various altitudes. This effect is especially pronounced at elevated altitudes. The increase in exhaust back pressure will significantly reduce the delivery ratio and increase the trapping efficiency. This study demonstrates that integrating DoE with AI algorithms can enhance the high-altitude performance of aircraft engines, serving as a valuable reference for further optimization efforts.

Targeted use of paraffinic kerosene: Potentials and implications

Aviation contributes to anthropogenic climate change mainly by contrails, CO2 and NOx emissions, whereof contrails are considered the largest single contributor to the radiative forcing from aviation. Powering aircraft with kerosene containing fewer or no-aromatics, i.e., “Sustainable Aviation Fuels” (SAF) or hydroprocessed, fossil-based kerosene, can significantly reduce contrail climate forcing. However, such kerosene is currently scarcely available. Moreover, less than 10 % of the flights worldwide cause more than 80 % of the contrail climate forcing. Hence, this study investigates a targeted allocation of paraffinic, i.e., aromatics-free kerosene to flights and flight segments with the highest contrail climate forcing, by calculating the resulting contrail energy forcing (in J) on 844 364 flight trajectories worldwide departing from five large European airports in 2019.The contrail radiative forcing integrated over contrail evolution (i.e., contrail energy forcing [J]) is simulated for a reference fleet powered with conventional kerosene of 14.1 m - % hydrogen content. 5 % of overall kerosene demand assumed to be paraffinic kerosene with 15.3 m - % hydrogen content is allocated via a uniform, a flight-specific and a segment-specific approach. The uniform allocation assumes that all flights receive the same blend of 5 % paraffinic kerosene. The other cases target 100 % paraffinic kerosene either to flights or segments with highest contrail energy forcing. Compared to the reference, the results indicate a reduction on contrail energy forcing by 4 %, 36 % and 55 %, respectively. For market shares of paraffinic kerosene up to 30 %, a segment specific allocation appears advantageous compared to a flight specific allocation. However, they might require airport and aircraft modifications. Uncertainties in contrail climate benefits can be reduced by providing additional information on kerosene properties and accurate meteorological data. Overall, this study highlights robust potentials of paraffinic kerosene to significantly reduce the climate forcing from aviation.

Impacts of geopolitics and policy on Latin American biodiversity and water resources

AbstractLatin America is a major agricultural producer with important natural resources. Efforts have been made to protect sensitive areas but are hindered by agricultural trade disruptions outside the control of individual countries due to globally integrated crop markets. This analysis assesses the effects of two trade shocks, that is, the war in Ukraine and vehicle decarbonization in the United States (US), on biodiversity and water resources in Latin America. Results show that an increase in maize and wheat exports from the region triggered by the war in Ukraine negatively affects biodiversity in Brazil and leads to cropland expansion into drought‐prone areas in Argentina and Chile. For the case of reduced crop exports from Latin America due to US vehicle decarbonization and the corresponding shift away from US maize ethanol, the pressure on arable land in areas of high biodiversity and water stress is eased. As opposed to agricultural carbon emissions, which have global impacts, biodiversity and water issues have a strong local and regional significance. Regulatory frameworks aiming to protect these regions should be forward looking to detect and shield vulnerable areas from future threats. Other changes affecting global agriculture and trade, for example, sustainable aviation fuels in the US or the European Farm‐to‐Fork policy, need to be anticipated for effective policies in Latin America [EconLit Citations: Q13, Q25, Q34, Q56].

Facilitating a Sustainable Aviation Fuel Transition in Italy

Civil aviation significantly contributes to “hard-to-abate” emissions, responsible for 2% of global CO2 emissions. This paper examines the most effective policies to promote Sustainable Aviation Fuels (SAFs) in Italy, using a multi-level policy analysis and a stakeholder-based case study approach. The policies reviewed comprise the international, European, and national level. The paper analyses at the international level, ICAO CORSIA and, at the European level, the Renewable Energy Directive (RED), ReFuel EU, and the EU Emissions Trading System (EU ETS) for aviation. Italy has not yet implemented specific policies targeting SAF transition, which is challenging due to commercialization issues and policy inconsistencies. These include the price gap between SAF and conventional fuels, different definitions adopted, and environmental objectives pursued with respect to sustainable fuels by ICAO and the EU. Other challenges include double-counting risks and fuel tankering practices. This article contributes to Italy’s SAF policymaking by developing a stakeholder-based quantitative survey, whose results suggest that three measures are key: tax subsidies for technology and infrastructure users, tax credits for upgrading production infrastructure, and tax breaks for SAF-using companies, fuel handlers, and distributors.

Spatially-explicit land use change emissions and carbon payback times of biofuels under the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA)

The Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) requires airlines to offset their greenhouse gas (GHG) emissions above 2019 levels by either buying carbon offsets or using Sustainable Aviation Fuels (SAFs). These are drop-in jet fuels made from biomass or other renewable resources that reduce GHG emissions by at least 10 % compared to kerosene and meet certain sustainability criteria. This study assesses the direct land use change (DLUC) emissions of SAF, i.e., GHG emissions from on-site land conversion from previous uses (excluding primary forests, peatlands, wetlands, and protected and biodiversity-rich areas) into alternative feedstocks, considering spatial variability in global yields and land carbon stocks. The results provide DLUC values and carbon payback times at 0.5-degree resolution for six SAF pathways, with and without irrigation and a medium-input intensity, according to CORSIA sustainability criteria. When excluding CORSIA non-compliant areas, soybean SAF shows the highest mean DLUC factor (31.9 ± 20.7 gCO2/MJ), followed by reed canary grass and maize. Jatropha SAF shows the lowest mean DLUC factor (3.6 ± 31.4 gCO2/MJ), followed by miscanthus and switchgrass. The latter feedstocks show potential for reducing GHG emissions over large areas but with relatively greater variability. Country-average DLUC values are higher than accepted ILUC ones for all pathways except for maize. To ensure the GHG benefits of CORSIA, feedstocks must be produced in areas where not only carbon stocks are relatively low but also where attainable yields are sufficiently high. The results help identify locations where the combination of these two factors may be favourable for low-DLUC SAF production. Irrigated miscanthus offers the highest SAF production potential (2.75 EJ globally) if grown on CORSIA-compliant cropland and grassland areas, accounting for ∼1/5 of the total kerosene used in 2019. Quantifying other environmental impacts of SAFs is desirable to understand sustainability trade-offs and financial constraints that may further limit production potentials.

Diversity in the acceptance of sustainable aviation fuels: Uncovering varying motivational patterns

The aviation sector’s significant contribution to greenhouse gas emissions has spurred interest in sustainable aviation fuels (SAF) as a means to mitigate environmental impact. This study examines user diversity in the public acceptance of power-to-liquid aviation fuels (eSAF), exploring varying attitudes towards the environment, flying, and eSAF adoption. Through a quantitative survey of a representative German sample, three distinct segments emerged: the Environment-Centered Approvers, the Flying-Centered Approvers, and the Skeptical. The Environment-Centered Approvers prioritize environmental concerns and perceive moral obligations to use eSAF for climate protection. In contrast, the Flying-Centered Approvers prioritize the continuation of flying with reduced environmental impact, while the Skeptical exhibit a more cautious and uncertain stance towards eSAF adoption. The study highlights the importance of tailoring communication strategies based on the unique motivations and concerns of each subgroup to effectively promote eSAF adoption.

Fischer-Tropsch Synthesis for the Production of Sustainable Aviation Fuel: Formation of Tertiary Amines from Ammonia Contaminants.

Fischer-Tropsch synthesis combined with product workup is a promising route toward synthetic aviation fuel from renewable hydrogen and carbon sources like biomass, CO2, and waste. Cost savings can be achieved by reducing the number of gas treatment steps in new plants, but the consequence of contaminants in the feed needs investigation. While feeding 2.6 ppmV ammonia to a Fischer-Tropsch reactor, it was shown that ammonia was predominantly chemically converted into organic amines, with most nitrogen found in the water phase (89%), followed by heavy wax (7%) and light wax (1%). The concentration difference between water and light wax was shown to be due to the post-condensation separation of amines on polarity. Amines up to a chain length of 120 were detected in the heavy wax with MALDI-FT-ICR-MS, which, in combination with the high nitrogen content, suggests that amines have a similar chain growth probability compared to the main hydrocarbon products. Detailed product analysis with three independent analytical techniques showed that tertiary N,N-dimethylalkylamines were by far the most abundant amine class. This suggests that ammonia is decomposed on the cobalt surface and, potentially as a dimethylamine fragment, incorporated in the growing chain. Further evidence was obtained from the abundance of trimethylamine and from the reconciled nitrogen product analysis up to C100, which showed that the amine product distribution followed from naphtha onward the same ASF kinetics as alkanes and oxygenates while being distinctively different from the alkene distribution. The presented findings provide further avenues for studies of the Fischer-Tropsch reaction mechanism and indicate the opportunity of cost saving on gas treatment, while further validation is required to assess the impact on hydrocracking and product quality.

Is Biofuel HVO An Alternative In Aviation? An Infodynamic Comparative Analysis

The transition from fossil fuels to sustainable alternatives is imperative. This research evaluates Hydroprocessed Vegetable Oil (HVO) as a substitute for Jet A-1 in aviation. Focusing on droplet sizes in fuel sprays, which are critical for optimizing combustion, we explore an informational perspective for comparative analysis. Integrating information theory principles, we introduce the terms informature, infotropy, and infosensor that quantify and capture the nondeterministic nature of physical systems. Our analysis reveals similar drop size distributions for HVO and Jet A-1, with the Gamma function effectively characterizing the distributions. Both fuels exhibit spray complexity evolving toward higher states, emphasizing the role of aerodynamic forces and minimum development distance in atomization. We propose a novel lexicon, infodynamics, viewing sprays as networks of information flows, with infotropy providing context-rich insights. HVO is endorsed as a viable alternative, with broader implications for sustainable aviation solutions and understanding complex engineering processes.

Hydrodeoxygenation of C15 furanic precursor over mesoporous NiMo-ZrO2 composite catalysts for the production of sustainable aviation fuel

Sustainable aviation fuel (SAF) is essential for achieving carbon neutrality in the transportation sector. This study elucidates the production of SAF range C9-C15 branched alkanes by hydrodeoxygenation (HDO) of C15 furanic precursor derived from 2-methylfuran and furfural via hydroxyalkylation-alkylation reaction. HDO reaction was performed using high surface area mesoporous NiMo-ZrO2 composite catalysts that exhibited high selectivity to central SAF alkanes (C13-C14). Deoxygenation follows a complex reaction network involving furanic double bond saturation and furan-ring opening reactions in series, followed by the cascade of HDO, dehydroformylation, and C-C bond cleavage. The present investigation enlightens the impact of calcination temperatures and metal (Mo and Ni) contents on structural stability, physicochemical properties, and catalytic performance of NiMo-ZrO2. Both Ni and Mo stabilized the tetragonal ZrO2 phases with improved surface area. The catalytic activity proliferated with rising calcination temperature till 873 K due to the enrichment of Mo-O-Zr acidic species and deteriorated beyond this temperature owing to the generation of crystalline MoO3/Zr(MoO4)2 species. NiMo alloy formation was enhanced, and concurrently, acidity was reduced with increasing Mo content. 30 wt% MoO3-containing catalyst showed the best catalytic activity due to the proper balance between acidity and NiMo alloy. Oxygenate conversion was boosted by increasing NiO addition up to 15 wt% due to the enhanced Ni and NiMo alloy formation and decreased at 20 wt% owing to the evolution of catalytically inactive bulk metal oxide species. Catalytic cracking was prominent at elevated reaction temperatures, with significant amounts of C13 alkane.

New technologies in combustion chambers of aircraft turbine engines

The paper presents the projected emissions of combustion components over the next few years. The basic tasks that a modern combustion chamber must fulfill were defined. The process of hydrocarbon combustion in the theoretical and actual cases was analyzed. The assessment evaluates the effect of engine operating parameters such as rotational speed, thrust, temperature downstream the compressor and combustion on the formation of toxic combustion components. The paper also presents alternative fuels. One of the most promising aspects related to the matter is the use of sustainable aviation fuels - SAF. Alternative methods of powering aircraft engines, such as hydrogen or nuclear propulsion, were presented. An analysis on the latest combustion chamber design systems that allow to reduce the amount of exhaust gasses emitted into the atmosphere was conducted.

Comparison of Emission Properties of Sustainable Aviation Fuels and Conventional Aviation Fuels: A Review

In order to achieve the International Air Transport Association’s (IATA) goal of achieving net-zero emissions in the aviation industry by 2050, there has been a growing emphasis globally on the technological development and practical application of sustainable aviation fuels (SAFs). Discrepancies in feedstock and production processes result in differences in composition between SAFs and traditional aviation fuels, ultimately affecting the emission performance of the two types of fuel. This paper discusses the impact of CO2/NOx/SO2/CO/PM/UHC emissions from the aviation industry on the natural environment and human health by comparing the two types of fuel under the same conditions. Fuel combustion is a complex process in the combustor of an engine, which transfers chemical energy into heat energy. The completeness of combustion is related to the fuel properties, including spray, evaporation, and flammability. Therefore, engine performance is not only affected by fuel performance, but also interacts with engine structure and control laws. The CO2 emissions of SAFs differ significantly from traditional aviation fuels from a lifecycle analysis perspective, and most SAFs can reduce CO2 emissions by 41–89%. Compared with traditional aviation fuels, SAFs and blended fuels can significantly reduce SO2 and PM emissions. Pure Fischer–Tropsch hydroprocessed synthesized paraffinic kerosine (FT-SPK) can reduce SO2 and PM emissions by 92% and 70–95% respectively, owing to its extremely low sulfur and aromatic compound content. In contrast, the differences in NOx emissions between the two types of fuel are not significant, as their generation mechanisms largely stem from thermal drive and turbulent flow in the combustor, with emissions performance being correlated to power output and flame temperature profile in engine testing. CO and UHC emissions are related to engine operating conditions and the physical/chemical properties of the SAFs, with no significant upward or downward trend. Therefore, SAFs have significant advantages over conventional aviation fuels in terms of CO2, SO2, and PM emissions, and can effectively reduce the hazards of aviation to the environment and human health.

How do airports align with sustainability? An analysis of the world's 150 busiest airports

AbstractThis study represents the first in‐depth analysis of the global airport industry's compliance with the Sustainable Development Goals (SDGs), assessing the SDG alignment of the world's 150 busiest airports across 48 countries, which collectively account for approximately 60% of global air traffic in 2019. We discovered a 42% overall alignment with the SDGs, illustrating the aviation sector's relatively slow incorporation of green technologies and sustainable practices, especially when contrasted with industries such as Oil and Gas (O&G), and banking. Notably, a subset of 23% of airports demonstrates high alignment, characterized by implementing targeted SDG actions and establishing comprehensive monitoring and evaluation frameworks, indicating a significant, albeit challenging, shift toward sustainability. Our analysis also pinpoints that airports in Europe and those handling larger passenger volumes exhibit more substantial alignment, attributing this to the influence of Europe's stringent sustainability regulations and the prioritization of passenger‐focused operations on enhancing SDG commitments. Conversely, an airport's alignment with the SDGs is not significantly predicted by its host country's national SDG scores, suggesting that regional sustainability pressures exert a more direct influence on airport practices than national achievements. These findings lead to recommendations for standardizing SDG reporting and developing specific metrics for tracking progress at airports, alongside advocating for governmental and international entities to establish regulatory frameworks, financial incentives, and certification programs to enhance global aviation sustainability.

Assessing the particulate matter emission reduction characteristics of small turbofan engine fueled with 100 % HEFA sustainable aviation fuel

With the continuous increase in global air transportation, the impact of ultrafine particulate matter (PM) emissions from aviation on human health and environmental pollution is becoming increasingly severe. In addition to carbon reduction throughout the lifecycle, Sustainable Aviation Fuels (SAF) also represent a significant pathway for reducing PM emissions. However, due to issues such as airworthiness safety and adaptability, existing research has mostly focused on the emission performance of SAF when blended with traditional fuels at <50 %, leaving the emission characteristics of higher blending ratios to be explored. In this study, using measurement methods recommended by the International Civil Aviation Organization (ICAO), the PM emission reduction characteristics of small turbofan engines fueled with 100 % Hydroprocessed Esters and Fatty Acids (HEFA)-SAF were experimentally evaluated and compared with traditional fuels RP-3 and Diesel, while avoiding the interference of lubricant blending combustion. The results showed that the peak number concentration of particle size distribution (PSD), PM total number, as well as the number and mass concentration of non-volatile particulate matter (nvPM) decreased initially and then increased with rising thrust conditions. HEFA-SAF exhibits PSD with smaller diameters, and the Geometric Mean Diameter (GMD) ranges from 7.7 nm to 20.3 nm under all conditions. Both volatile particulates (vPM) and nvPM from HEFA-SAF are significantly reduced, with nvPM number emission index (EIn) being 92 % and 71 % lower than Diesel and RP-3, respectively. The nvPM mass emission index (EIm) also shows reductions of 96 % and 89 % compared to Diesel and RP-3. Microscopic characterization also indicated that using HEFA-SAF emitted fewer and smaller PMs. This study establishes a foundation for evaluating the effectiveness of 100 % SAF in reducing PM emissions within the aviation sector, and contributes to the airworthiness regulations development related to the use of SAF in a variety of application environments, alongside enhancing environmental protection measures.

Spatially Varying Costs of GHG Abatement with Alternative Cellulosic Feedstocks for Sustainable Aviation Fuels.

Cellulosic biomass-based sustainable aviation fuels (SAFs) can be produced from various feedstocks. The breakeven price and carbon intensity of these feedstock-to-SAF pathways are likely to differ across feedstocks and across spatial locations due to differences in feedstock attributes, productivity, opportunity costs of land for feedstock production, soil carbon effects, and feedstock composition. We integrate feedstock to fuel supply chain economics and life-cycle carbon accounting using the same system boundary to quantify and compare the spatially varying greenhouse gas (GHG) intensities and costs of GHG abatement with SAFs derived from four feedstocks (switchgrass, miscanthus, energy sorghum, and corn stover) at 4 km resolution across the U.S. rainfed region. We show that the optimal feedstock for each location differs depending on whether the incentive is to lower breakeven price, carbon intensity, or cost of carbon abatement with biomass or to have high biomass production per unit land. The cost of abating GHG emissions with SAF ranges from $181 Mg-1 CO2e to more than $444 Mg-1 CO2e and is lowest with miscanthus in the Midwest, switchgrass in the south, and energy sorghum in a relatively small region in the Great Plains. While corn stover-based SAF has the lowest breakeven price per gallon, it has the highest cost of abatement due to its relatively high GHG intensity. Our findings imply that different types of policies, such as volumetric targets, tax credits, and low carbon fuel standards, will differ in the mix of feedstocks they incentivize and locations where they are produced in the U.S. rainfed region.

Decomposing Carbon Intensity Trends in China’s Civil Aviation: A Comprehensive Analysis from 1998 to 2019

Carbon emission intensity is an important index reflecting an entity’s low-carbon competitiveness. This paper presents an extended logarithmic mean divisia index (LMDI) model to dissect carbon intensity within China’s civil aviation from 1998 to 2019, revealing a significant reduction in CO2 emissions per air transport revenue. It attributes this decrease to technological advancements, optimized fleet structures, and improved operational efficiencies, highlighting the impact of larger, more efficient aircraft and enhanced load factors. The study also explores economic factors influencing carbon efficiency, suggesting a comprehensive approach encompassing technological innovation and strategic operational improvements for sustainable aviation development.

Pathway to zero emissions in global tourism: opportunities, challenges, and implications

Human emissions must reach zero by 2050 to avoid dangerous climate change. Most sectors have achieved a downward path for their greenhouse gas emissions, but tourism’s emissions have continued to grow. We explore scenarios to reduce global tourism emissions and find only a narrow pathway to zero emissions tourism that could lead to net zero by 2050 while not severely damaging the tourism economy. Our study uses a system dynamics model. We describe the business-as-usual scenario, including its consequences for emissions and for tourism’s share of the remaining global carbon budgets if the world is to limit global temperature rise to 1.5 or 2 °C. We explore 45 possible policy approaches, like taxes and subsidies, infrastructure investments, off-sets, technology, behavioural changes, and sustainable aviation fuels. Key measures appear to be a mandate for e-fuel mixing up to 100% by 2050, and a multi-trillion USD investment in hydrogen-powered electric aircraft and high-speed rail infrastructure. We find that a limited renewable energy supply will constrain the growth of aviation if it is to be zero emissions in 2050. A risk-analysis explores the robustness of the policies. Finally, we discuss the consequences of the zero emissions tourism (ZET) scenario we propose.

A novel integrated gas-cooled fast nuclear reactor and vanadium chloride thermochemical cycle for sustainable fuel production

The continuous growth of anthropogenic carbon emissions from the aviation industry has emphasized the urgent request to substitute traditional aviation fuels with Sustainable Aviation Fuels (SAFs) because SAFs can potentially reduce carbon emissions by around 50–90% as compared to traditional kerosene-based fuels. In this paper, a novel SAF production pathway is developed which is based on biomass processing, nuclear energy, and thermochemical reactions of the vanadium chloride cycle for SAF, clean power, and hydrogen production. The entire system is assessed thermodynamically in terms of energy and exergy performances. Various sensitivity analyses are computed to determine the reliable operating parameters. The study concludes that biomass-to-SAF energetic and exergetic performance is achieved to be 76.72% and 74.35%. The energetic and exergetic performance values, through efficiencies, of the V–Cl cycle are calculated to be 68.08% and 53.50%, respectively. For hydrogen production and storage, an energy penalty of around 16.83 kJ/kg H2 is calculated, which results in an efficiency penalty of 6.18%. The overall energetic and exergetic efficiencies of the proposed integrated system are found to be around 59.79% and 23.78%, respectively.

The Net Zero policy and its impact on the air transport network: Considering the modal competition between airlines and high-speed rail

This study explores the relationship among carriers’ behavior, the increase of operational cost under the Net Zero policy, and the workability of greenhouse gas (GHG) reduction. We adopted the bi-level network optimization model with a modification on the passenger utility function to reflect the effect of carbon dioxide reduction preference. We considered a four-node network in which high-speed Rail is available for short-haul transport and aviation is used for long-haul transport. The results suggest that when the fuel price increases owing to the usage of Sustainable Aviation Fuel (SAF) and environment-friendly aircraft, airlines lose their profits and the passenger flow decreases. However, when passengers become more sensitive to the environmental load of travel, airlines are incentivized to use SAF and environment-friendly aircraft to gain more passengers, provided fuel costs do not rise sharply. Our results suggest that the effectiveness of GHG reduction largely depends on the cost increase and therefore, when imposing more stringent regulations on all airlines, new problems may arise from the decline in international communication.

Corporate Social Responsibility Practices of Selected Airline Companies: Inputs for a Sustainable Aviation Service

This paper tries to identify the strategic corporate social responsibility of selected airline companies to ascertain inputs for the creation of a sustainable service delivery, by looking at the implementation level of its corporate social responsibility in the environmental, philanthropic, economic and ethical areas. The study shows that in terms of environmental responsibility, waste segregation has the highest level of practice, while carbon footprint reduction is the lowest. Philanthropic activities participated in by employees is the most frequently practiced among other philanthropic responsibility initiatives, while the provision of scholarship grants is the least practiced. For economic responsibility, the recruitment of diverse talent received the highest mean score indicating it as the most practiced activity, while financial management strategy practices is the most challenged. As far as ethical responsibility is concerned, the practice of honesty is prevalent, while direct stakeholder involvement in planning the manual of ethical operations is almost none. The study also explored whether there was a significant difference in the assessment of CSR strategies between the two groups of respondents. The results indicated that there was a significant difference in the assessments of employees and passengers in terms of environmental, philanthropic, economic, and ethical responsibilities in comparison to management administrators. Moreover, the challenges encountered in the implementation of CSR strategies were identified and ranked, providing insights into the perceived difficulties faced by airline companies in implementing CSR strategies. Based on the findings of the study, recommendations for responding to the challenges of implementing CSR strategies were proposed. These recommendations include additional signage for environmental awareness, ensuring the sustainability of philanthropic activities, crafting financial measures to address constraints, and ensuring sustainable implementation of its manual of operation. The findings and recommendations provides inputs to for a sustainable service delivery and promoting responsible business practices in the airline industry.