Çam, Ömer; Kılıç, Uğur; Tanrıverdi, Gökhan

Air transportation offers significant speed advantages, particularly on medium- and long-haul routes, yet it contributes disproportionately to environmental pollution, especially on short-haul domestic flights. In contrast, high-speed rail (HSR) represents a more sustainable alternative. This study examines CO2 emissions from narrow-body and wide-body aircraft in comparison with Shinkansen trains on selected Japanese domestic routes, where air and HSR services directly compete, focusing on the Haneda–Osaka and Haneda–Fukuoka corridors. Japan is notable for having the highest use of wide-body aircraft on domestic routes worldwide, which makes this context particularly relevant for examining the environmental impact of aircraft type. Emission data for each aircraft type were obtained using the integrated aircraft noise and emissions modeling platform (IMPACT) developed by EUROCONTROL. The results indicate that wide-body aircraft emit at least twice as much CO2 as narrow-body jets, highlighting the critical influence of aircraft type on short-haul emissions. Shinkansen trains, particularly the N700 series, demonstrate the lowest per-passenger emissions, achieving approximately 20% greater efficiency than the older 700 series. The study provides policymakers with a meaningful perspective, emphasizing that deploying wide-body aircraft on short-haul routes is inconsistent with environmental sustainability goals.

Ecer, Fatih; Tanrıverdi, Gökhan; Yaşar, Mehmet; Görçün, Ömer Faruk

In line with the 2050 net zero emission target, sustainable aviation fuel (SAF) is recognized as one of the most effective decarbonization solutions for the aviation industry, which has been identified among the critical areas for mitigating climate change. However, although sustainability issues and decarbonization have attracted scholars' attention in various terms for the airline industry, we identified some significant theoretical and managerial gaps as follows: (i) the number of studies evaluating sustainable suppliers by airlines via multi-criteria decision-making (MCDM) approaches are very few, (ii) the extant literature has no paper addressing airlines' SAF supplier selection process, and (iii) no widely established criteria set in the literature to evaluate the SAF suppliers for airlines. We propose a novel model for the decision-making process of airlines' sustainable SAF supplier selection, including 39 criteria from 5 aspects considering the triple bottom of sustainability. The proposed model involves the combination of the logarithmic percentage change-driven objective weighting (LOPCOW) and measurement alternatives and ranking according to the compromise solution (MARCOS) approaches' extended forms based on the interval-valued fuzzy neutrosophic numbers (IVFNN). A comprehensive sensitivity and comparison control is further exploited to display the developed framework's robustness and practicality. Our results suggest that airlines prioritize the green initiatives of SAF suppliers over the economic aspect in the process of sustainable SAF supplier selection. We provide some managerial and policy insights for practitioners and policy-makers in the airline industry and some directions for further research.

Tanrıverdi, Gökhan; Merkert, Rico; Karamaşa, Çağlar; Asker, Veysi

Airline sustainability, defined as both decarbonization and long-term financial survival, has become critical especially since the onset of the COVID-19 pandemic. Our paper investigates the multi-dimensional effects of the COVID-19 crisis on airlines’ sustainability performance using data from 56 airlines for the period before, during and early after the pandemic (2017–2021). We develop and use a novel multi-criteria MEREC–CoCoSo/Borda performance measurement model tailored to the airline industry. Our results suggest that while operational results have dominated sustainability weights throughout the period, the financial pillar has gained considerably in importance while the decarbonization criterion decreased in weight in 2020. However, from 2021, decarbonization started to become more important again in the “new normal” and sector recovery. In terms of overall and sustained sustainability, low-cost carriers and small full-service carriers with predominantly domestic networks are ranked as best performers. Renewing fleet, attaching decarbonization conditions to government aid and reviewing airport slot policies are important to prepare the aviation industry for the next pandemic or disruption.

Ekici, Selcuk; Ayar, Murat; Kilic, Ugur; Karakoc, T. Hikmet

This study analyzes two types of aircraft offered to the industry by two different manufacturers on an identical route and trajectory for commercial aviation and the noxious emissions resulting from equipping these aircraft with the most frequently used engine combinations today. The research covers the most recent Base of Aircraft Data (BADA v4.2_1), the Aircraft Noise and Performance (ANP v2.3), and the ICAO Engine Emission Database (254-ICAO EDDB25/FOCA) based integrated aircraft noise and emissions modelling platform (IMPACT) developed by EUROCONTROL. The striking findings in fuel consumption and emissions of four different scenarios during identical flight operations are detailed. The research presents the application of a systematic aircraft-engine pair decision mechanism for investigators, scientists, airline operators, policy analysts and legislators, in accordance with a comprehensive computer simulation method that consistently acknowledges the fuel consumption and emissions analysis of aircraft-engine parings.

Tanrıverdi, Gökhan; Ecer, Fatih; Durak, Mehmet Şahin

The COVID-19 pandemic has created unexpected demand for air cargo in terms of rapid mobility of critical basic needs. Air cargo carriers aim to maximize their profits by taking advantage of the current demand and using their limited capacity in the right place. At this point, some of the qualifications of the airports in the places where demand plays a crucial role in this decision of the carriers. Thus, evaluating the factors considered in the airport selection for air cargo carriers during the COVID-19 period is curious. This study proposes a triangular fuzzy Dombi-Bonferroni best-worst method (BWM) framework with vast flexibility to establish the priority preferences of factors considered in selecting airports. The fuzzy BWM model becomes a superior decision support system by combining the Bonferroni mean operator's ability to consider interrelationships between attributes and the flexibility of the Dombi operator. In this sense, we highlight eighteen criteria based on five airport aspects: location, physical features, performance, costs, and reputation. Findings reveal that the foremost aspects are location and costs, whereas the most crucial factors are airport charges and handling charges. The study suggests that airports should follow a low-price policy for airport-related charges without compromising their sustainability to have a share of the increasing number of air cargo flights, especially during the COVID-19 period, when airline passenger flights are decreased. The study is crucial in deciding the strategy and policy of air cargo carriers and airports during the pandemic period.

Tanrıverdi, Gökhan; Lezki, Şenay

Our paper determines the best competitive strategy that can be implemented by existing and potential air cargo carriers in the Turkish Air Cargo Industry with the operationalization of Istanbul Airport (IGA) and reveals the competitiveness level of the industry for four bases. We look at the competitiveness levels by analyzing the competitive environment of the industry nationally and internationally both before and post IGA (estimated). We use fuzzy TOPSIS (FTOPSIS) based on the Fuzzy AHP (FAHP) to handle vagueness, which is inherent in the nature of new competition conditions integrating the framework of Porter's five forces analysis. In our study, we use the five forces as our main criteria (with a total of 19 sub-criteria) and the competitive strategies as our alternatives. Our results reveal that the cost-focused strategy is the best competitive strategy that can be implemented by existing and potential carriers in the industry. Another significant result underscores the fact that IGA increases the competitiveness level of the Turkish Air Cargo Industry both nationally and internationally to a fairly high level. Also, the threat of potential competitors is first among the five forces in the industry's new conditions. Our study fills the gap in the literature on the effects of major structural changes in an air cargo industry on the competition among carriers.

Polater, Abdussamet

The purpose of this study is to investigate the key factors of airport logistics surge capacity and the relationships between these elements. The findings show that successful airport surge capacity management is closely related to prioritizing the flights and operational activities; considering the influx of local people to airports and local infrastructure capacity in the planning phase; developing suitable methods to encourage people to take part in surge operations; providing uninterrupted communication in and out of airport. In view of the above-stated findings this study suggests that airports can meet the surge demand through systematic capacity planning of the existing and additional human, supply, system and space elements by considering experienced or anticipated capacity shortages in disaster conditions.

Tanrıverdi, Gökhan; Bakır, Mahmut; Merkert, Rico

This paper aims to draw lessons from retrospectively evaluating the evolution of the air transport discipline right up to the COVID-19 outbreak through the Journal of Air Transport Management (JATM), the main scholarly air transportation journal globally. As such, this study deploys a comprehensive bibliometric analysis and graphical mapping of the JATM knowledge body through CiteSpace visualization of 1483 JATM papers from 2001 to 2019. Our results suggest that while the industry has experienced pandemics and economic crises in the past, both were not dominant in influencing JATM literature neither in frequency nor in impact. That said, recovery, crisis and disruption are important key words in JATM papers not just in regard to safety and economic crisis management but increasingly also related to health concerns with recent key papers published in the pandemic and recovery management context which may have helped the industry dealing with the current crisis as well as current JATM papers on this topic assisting with preparing for a transitioning out of COVID-19 world.