A Thematic Analysis, Definition, and a Green Aviation Conceptual Model—Putting It All Together

Abstract

The notion of ‘Green Aviation’ has gained interest over the last three years. However, there is no clear definition of what the term green aviation means. Many interpret the meaning to describe the focus of their study, resulting in a diverse understanding of what it entails. In this study, we present our systematic approach to proposing a definition that meets all stakeholders’ understanding and extract from the definition an actionable framework. Focusing on total quality management and circular economy frameworks, we followed a two-step approach towards the definition: Conduct a thematic analysis on the body of literature, followed by consultations with green aviation professionals. Green aviation is defined as sustainable aviation practices to minimize environmental impact and continuously improve social wellbeing. This definition is used to extract a conceptual framework to help future research work and sustainability integration into the practitioner’s strategic planning. The proposed framework adapts the triple bottom line theory to include an organization’s level of social, environmental, and economic integration towards increased ‘sustainability value’. Our study findings provide organizations with insight into pathways towards the successful integration of their environmental goals into their strategic planning, where continuous improvement and social responsibility play a central role.

1. Introduction

Despite geopolitical tensions, the exponential progress in digitally integrated innovations and technologies, infrastructure improvements, and operational measures continue to increase in the same pattern as the rate of globalization. International air transport reacts to increased levels of globalization via innovation integration, increased efficiency, and the scaling up of supply to demand. The tradeoff for this increased global connectivity is climate impact and organizational adaptation capabilities.

1.1. Climate-Friendly Transformation of the Aviation Sector

Therefore, there is an urgent need to transform the aviation sector and its development into a more climate-friendly industry [1,2,3]. The exponential increase in air travel not only has a significant impact on the climate, via increased emissions, but negatively affects social ecosystems due to interference from noise pollution. For example, ref. [4] found that a 10 dB increase in noise levels from airports caused a 3.5% increase, on average, in hospitalization/death from cardiovascular disease. Moreover, from a climate impact perspective, and with an annual growth of 5% which may surpass seven times the 1990 carbon emissions levels by 2050 [IATA, 2009], air transportation contributes 13% of all transport carbon emissions, and around 24% of the net effect of nitrogen oxide emissions [5,6].

In general, the majority of the world today perceives the continued emission of greenhouse gases (GHGs) as the reason for irreversible climate change [7]. Some believe that we still have a chance to reverse its climate impact, and a few still argue that climate change is not caused by GHGs. Consequently, the world has switched gears to a carbon-neutral or carbon-free global economy. Governments have agreed that the hope to avert disasters at the human civilization level needs to be achieved by mid-century, setting the stage for drastically increasing innovation in all areas of engineering, management, supply chains, education, regulations, behavior, and governance. We agree with the observation made by [7]: “It is unfortunate that the danger posed by climate change is not yet regarded as an emergency that requires an “all hands-on deck” global effort”.

It seems that this lack of global cooperation and coordination is hampered by geopolitical tensions, shifts in ideological positions across a number of influential countries, wars, human migration, the fast pace of digital innovations and technologies, increased frequency and severity of climate conditions, economic instability in many markets around the globe, the overall global psychological state of the population, and general distrust in the government’s capabilities to ensure the safety, security, and equitable welfare of its citizens.

In addition, in 1830, the world’s population was well below one billion. In less than 200 years, the population has increased to 8 billion. This rapid expansion of more than eightfold has increased the demand for food, water, and energy, resulting in an exponential increase in the associated greenhouse gas emissions. Innovations have yet to come close to balancing global growth with GHG emissions, and the gap between the demand for global development and associated GHG emissions continue to expand.

1.2. Greenhouse Gases

Greenhouse gas emissions have become the center of attention with global climate concerns, as evidenced by the growing body of literature in the area, despite its controversial causes [8,9]. Therefore, the notion of sustainability has emerged from these exponentially increasing concerns over the last couple of decades. Sustainability studies spanned all areas of work and research disciplines, investigating the influences and impacts of climate change, air quality degradation, resource depletion, and waste increase, among others. As such, industries from energy to agriculture, including dependency on transportation, face GHG emissions challenges, and everyone must participate in providing solutions and adapting to new realities [10].

Ref. [11] presented the GHG contributions in different sectors, where transportation is 13% compared to industry (19%), forestry (17%), agriculture (14%), waste (3%), buildings (8%), and energy supply (26%). From the total transportation, 10% of GHG emissions are attributed to roads, 1% to combined rail, shops, and others, and 2% to aviation.

Table 1. Contribution of different sectors to GHG emissions.

Sector	GHGs	References	Source
Energy	73%	[12]	Energy (electricity, heating) generation from fossil fuels
Transportation	14%	[13]	All forms of transportation (road, rail, sea, air)
Aviation	2.50%	[13]	Passenger and freight; radiative forcing increases impact to 3.5%
Industry	21%	[14]	Manufacturing, construction, cement, and steel
AFOLU *	18–20%	[15]	Deforestation, livestock, and soil degradation
Buildings	6% direct, 17–19% indirect	[16,17]	Direct from fossil fuel use; Indirect from electricity and heat use

* AFOLU: Agriculture, Forestry, and Land Use. Note: Core Writing Team (2014) from IPCC provides further details and information on GHG emissions.

provides further information on the various sources.

From 1990 to 2014, the EU-28 showed a 22.4% decrease in GHG emissions [18]. By 2014, all sectors had taken part in this GHG emissions reduction, with the exception of transportation, which showed an increase of 13.3% [19]. This upward trend in aviation emissions continues to date, where the aviation sector has been shown to be the fastest growing part of the transportation industry, and therefore, must assume responsibility for an important portion of greenhouse gas emissions [20]. Consequently, the last decade has seen a dramatic increase in interest in environmentally sustainable aviation, especially after the 2015 Paris Climate Agreement, which inspired the world to commit its participation in efforts to reduce GHG emissions. The 2016 launch of the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) was aimed at stabilizing the net carbon emissions (primarily CO₂) caused by international air transportation.

Aviation stakeholders are all impacted by national environmental regulations as well as by international treaties, such as the 2015 Paris Climate Agreement and CORSIA, and are expected to work together and embrace innovation towards limiting the increase of the global average temperature to 1.5 °C over pre-industrial levels. This affects all stakeholders, including airlines (passengers and cargo), airports, organizations, governments (aviation authorities), service sector, and manufacturing (throughout the supply chain). Challenges and efforts made towards environmental mitigation are central to the development of the air transport market, which is primarily driven by passengers [8,9] and cargo [21]. This area of study advocates the importance of a comprehensive (all stakeholders) global perspective in aviation in today’s fast-paced world, as it affects everyday life, including economic, social, and natural environments.

Considering these impacts on the climate and social ecosystems, in this article, we focus on the sustainability of all stakeholders who are equally affected, including but not limited to the private sector, non-governmental organizations (NGO), the United Nations (UN), and cities. Most recently, these stakeholders have adopted the concept of ‘Green Aviation’ (GA) into their business repertoire. In this article, we aim to (1) review the literature on green aviation and consolidate their interpretations and/or treatment of the concept into one unified definition; and (2) develop a conception model that represents the definition and provides a flexible guideline for aviation stakeholders to align their climate goals with their strategic planning.

After this introduction, Section 1, we review the literature in Section 2, with a focus on the publications that directly address the concept of green aviation. We then elaborate, in Section 3, on the theoretical underpinnings of this research work. In Section 3, we draw on two frameworks used as best practices in the industry, namely total quality management and circular economy frameworks. We consider these two frameworks for the development of the concept and definition of green aviation. Section 4 details the methodology we followed to determine and propose the definition of green aviation, which entails two parts: the thematic analysis approach following conceptualized patterns and engaging the green aviation community for feedback towards a final definition of green aviation. Moreover, we unwrap the definition and elaborate on its components to provide detailed interpretations and application to its unified and inclusive characteristics. In Section 5, we discuss and conclude our study by summarizing what we have achieved and present its major highlights. We further provide suggestions for future research and implications/recommendations for practitioners.

2. Literature Review

Environmental studies can be considered the central theme of green aviation, and it is evident that the body of knowledge in aviation environmental research has expanded over the past decade in terms of the number of articles, journals, and diversity of topics, as corroborated by [22,23,24]. A preliminary search utilizing the Social Sciences Citation Index (SSCI Web of Science—WoS) with the keywords ‘Aviation’ and ‘Environment’ in the title yielded 110 articles, of which 72% fall within the domains of engineering and occupational health, with only 10 articles in the field of transportation and 2 in environmental studies. Employing the same keywords in the abstract search returned 3195 articles, of which 112 are categorized under transportation and 129 under transportation science technology, according to the WoS classifications.

Further refinement for environmental relevance within the SSCI categories of environmental studies yielded 67 articles. A subsequent attempt to locate publications related to the environment by substituting the keyword ‘Aviation’ with ‘Air Transportation’ did not yield relevant results. It was observed that utilizing the keyword ‘Climate’ in place of ‘Environment’ produced more pertinent outcomes, with 144 articles, all of which were relevant and predominantly focused on sustainable alternative fuels, carbon emissions, and policies/regulations.

This investigation corroborates the findings of [23], indicating that the body of knowledge in the field of green aviation remains limited based on the current search results. A subset of aviation environmental impact research focuses on the concept of green aviation, which has recently garnered attention from researchers, practitioners, and governments. Consequently, we conducted a search on green aviation and found that utilizing the terms “Green” and “Aviation” in the title and abstract yielded 58 and 481 articles, respectively, in the Web of Science (WoS) database.

Through a systematic examination of the articles in three stages—title, abstract, and full text—we identified 17 articles [7,11,20,23,25,26,27,28,29,30,31,32,33,34,35,36,37] that can be utilized to expand upon and consolidate the meaning of green aviation into one proposed definition.

Green aviation is conceptualized as the evolution of environmentally conscious practices and the advancement of technological innovations aimed at mitigating the overall or specific environmental impacts of air travel. This multidisciplinary concept, as reflected in the extensive literature, encompasses a wide range of strategies in the domains of aerodynamics, structures, materials, energy, and propulsion [10]. These strategies include the optimization of flight trajectories, the development of lightweight aircraft structures, all-electric systems and ground operations, composite materials, and the integration of innovative propulsion systems, such as flameless combustion and solid-oxide fuel cell turbofans. The overarching objective of green aviation is to achieve sustainable development within the aviation sector while minimizing greenhouse gas emissions and other pollutants.

One of the fundamental aspects of green aviation is the optimization of flight trajectories, which has been recognized as a significant area of research. The integration of environmental protection into trajectory optimization is essential for promoting sustainable development in civil aviation [38]. This approach not only enhances operational efficiency but contributes to the reduction of fuel consumption and emissions during flights. Furthermore, the adoption of low-carbon development models has gained traction globally, with countries aiming for carbon neutrality, thereby increasing the focus on green aviation [39]. The design and materials utilized in aircraft construction play a crucial role in achieving the objectives of green aviation. Lightweight structures are pivotal for enhancing fuel efficiency and reducing emissions. Wang et al. discussed how the development of novel lightweight materials and structures is critical for achieving carbon-neutral air transportation [40]. This is corroborated by [41], who emphasized the significance of innovative aircraft designs that maximize efficiency and minimize environmental impact. The utilization of advanced materials and design techniques, such as topology optimization, can significantly contribute to the sustainability goals of the aviation industry.

Moreover, the integration of hybrid electric propulsion systems is a promising avenue for reducing emissions in commercial aviation. Ref. [42] observed that hybrid electric propulsion systems can improve fuel efficiency and reduce CO₂ emissions by combining traditional fuel-burning engines with electric motors. This technology aligns with the European Union’s ambitious goal of achieving net-zero air transport emissions by 2050. The exploration of distributed electric propulsion systems further supports the green aviation initiative by offering more energy-efficient and environmentally friendly alternatives [39].

In addition to technological advancements, the establishment of comprehensive evaluation systems for green aviation development is vital. A framework for assessing the development of green civil aviation, which includes indicators related to environmental protection, technology, and human factors was proposed [43]. Such frameworks are essential for guiding policy decisions and ensuring that the aviation industry progresses toward its sustainability goals.

Considering the above, green aviation has yet to be defined in the literature; however, the notion of green aviation has only recently taken roots. The purpose of this study was to examine the concept of green aviation, which should capture in its meaning key factors and dimensions for the successful transformation of the aviation sector into a climate-friendly and sustainable ecosystem. The state of the art presented in this study shows an increasing interest, in the last two years, in the notion of green aviation, and provides a broad perspective of how researchers view green aviation and how professionals apply this notion to their practice. It seems that this notion is showing promise to better communicate environmental issues to stakeholders, primarily including airlines/airports, regulatory bodies, and passengers. The literature shows that the concepts, ideas, and processes regarding the perception of ‘green’ in green aviation are broad and not clear. Therefore, there is a need to provide some consensus of what green aviation entails.

3. Theoretical Background

3.1. Total Quality Green Aviation Management System

In this paper, we view the term ‘Green Aviation’ through the lens of total quality management (TQM), which is basically a holistic approach to manage quality assurance and facilitate its monitoring and control mechanisms. TQM is a philosophy that aims to establish a structured approach to the assessment, management, and continuous improvement of an organization’s business. It also includes the traceability of any errors that occur. An example of TQM is ISO (International Standards Organization) certification. Borrowing from enterprise resources planning systems, TQM entails the development of an enterprise business and technical architecture linking the customer to the supplier and planning to manufacturing and sales. The four-component cycle would look as follows: Client–Planning–Supplier–Manufacturing. This cycle operates around an accounting system and includes finance, inventory, assembly, and marketing at the components interfaces. Considering this high-level architecture (which may vary depending on context), it is evident that the purpose of TQM is primarily to manage the value and continuous improvement of money, people, products, and information (tangible and intangible assets). To realize (operationalize) TQM across these components and interfaces, mechanisms must be put in place; in this context, mechanisms represent the integration of tools, processes, and initiatives into activities such as agile human resources, customer satisfaction handling, employee engagement, competitiveness analysis, change management, control benchmarks, training, and documentation. Subsequently, we adapt TQM to the green aviation paradigm, as shown in Figure 1, to obtain the total quality green aviation management (TQGAM) system.

The idea of a total quality green aviation management system, in the context herein, implies that all stakeholders engage in the greening process entailing internal and external ones. Awareness, education, capacity building, knowledge acquisition, social responsibility, and talent management, become central themes in the total quality management paradigm. In addition, a total quality management system also entails processes, infrastructure, operations, management, strategy, and leadership. All this constitutes part of the organization. From an external perspective, a TQGAM system is centered around conducting business with common shared values partners and with social responsibility in mind. Moreover, mechanisms that ensure not only continuous improvement but their sustainability are necessary and implicit in the concept of a TQGAM system.

Finally, the concept of climate success appears in the literature to represent the mission-embedded green goals of the organization. Climate success has two perspectives, namely adaptation and mitigation, and ecosystem development [44]. Consequently, it can be viewed as the efforts to reduce an organization’s contributions to climate change to policy determined levels while sustaining the triple bottom line (elaborated later in the manuscript) across economic, social and environmental interests. Climate success can therefore be interpreted as a flexible notion that allows organizations to harmonize their values internally and globally by aligning their environmental goals with their strategy.

The pursuit of excellence is the hallmark of the total quality green aviation management system, as shown in Figure 1. TQGAM is a structured approach that is quality-centric and is reflected in the organization’s fabric, including processes, structure, and employees. TQGAM focuses on quality improvements and, hence, is connected conceptually to an organization’s continuous improvement initiatives and strategic change management. This approach provides a good standard for the aviation industry, which is increasingly competitive, under a lot of pressure to reduce its carbon footprint, and therefore requires the integration of new and disruptive innovations. The primary advantage of TQGAM integration is the potential for the systematic integration of innovations into organizational practices and the establishment of a sustainable relationship between achieving environmental goals and enhancing organizational efficiencies. A noteworthy study of TQGAM integration in the context of green aviation is illustrated by [45], where Emirates Airlines, by fostering a culture of continuous improvement and employee involvement, led to the significant improvements of operational effectiveness and sustainability.

TQGAM can be viewed as a framework to facilitate the development and sustainability of environmental impact of aviation operations metrics [46]. Moreover, the integration of TQGAM with green aviation practices can enhance the effectiveness of all carbon emission reduction programs, including but not limited to sustainable alternative fuels (SAFs), integration of newer more efficient aircraft, waste management, and operational optimization. Such an integration places emphasis on resource conservation and environmental protection [23]. Transitioning to green aviation necessitates a collaborative approach among various stakeholders, including airlines, airport operators, and regulatory bodies, and therefore specific management strategies are required [47]. As a framework, TQGAM also has allowances for the management of collaboration and communication among stakeholders towards the development of shared values and the harmonization with sustainability goals.

Therefore, such efforts may entail the integration of advanced technologies, optimization of operational practices, and establishing robust evaluation frameworks, thereby allowing the aviation industry to significantly reduce its environmental footprint and contribute global sustainable efforts. Finally, we add one more concept to extend the meaning of green aviation beyond technological innovations; that is, to encompass broader economic and regulatory frameworks. Ref. [48] emphasizes the need for legislative changes and technological modernization in the aviation sector to meet environmental standards. This approach is holistic and necessary for fostering a sustainable aviation ecosystem encompassing the required capabilities to adapt to the challenges posed by climate change and environmental degradation.

TQGAM can apply within the organization and/or across the sector. It represents the endeavor to commit to a quality culture which impacts all aspects of the organization and sector. The framework of TQGAM faces a number of internal and external challenges, ranging from specialized environmental talent management to time pressures to adapt with accelerating climate change. One of the most significant cross-cutting critical issues entails stakeholders’ management with contradictory or opposing goals and/or views/contexts. One recent example that we encountered in a Green Aviation conference in Chengdu relates to the sustainable aviation/alternative fules (SAFs). An airline company was pushing SAFs as the ultimate solution to meet international carbon emissions regulations/policies and climate goals; whereas, the suppliers of SAFs do not believe that this is true and/or feasible, nor are the passengers willing to pay for SAF research and associated development costs. This contradiction occurs between the airline, the regulatory body, the suppliers of SAFs, and the consumer. Yet, TQGAM does provide a framework for all stakeholders to cooperate, collaborate and develop under a shared common values paradigm.

These contradictions are not trivial and can be the most difficult to overcome, compared to technological development, especially considering that different stakeholders operate on different time scales and more dynamic life cycle stages of social–industrial processes. Nevertheless, TQGAM does bring into the picture stakeholder management, social contribution and wellbeing, industrial processes ranging from design to disposal/recycling (circular economy), resources sharing, geopolitical considerations, time scales, incentivization, collaboration, and standardization.

3.2. Green Aviation Circular Economy

The circular economy (CE) has gained attention recently to address primarily the management of waste and has evolved into a framework that is used in industry. The CE entails a global economic ecosystem where goods, services, land, labor, and capital are exchanged for various products and services, such that energy and natural resources are consumed in the process, thereby releasing waste and pollution into the biosphere, and consequently degrading the global environment with profound consequences for all [49]. More specifically, the ability to achieve a green aviation ecosystem is critical at this point for total global sustainability, that does not only recognize emissions from the burning of fuels but includes waste management as well.

However, we continue to have practices that impede progress towards that goal. For example, the persistent consumption of fossil fuels continues to contribute to environmental degradation on a global scale. Despite all efforts and regulatory interventions, moving towards a renewable energy ecosystem has been slow, to say the least. Fossil fuel use remains the primary source for every innovation in the renewable resources arena.

This is especially true in the case of developing countries where their major challenges and constraints entail economic and infrastructure facilitation, which consequently exacerbates their environmental impact agendas and economic growth [50]. Over the past decade, research on the transition to green economy has increased, but most studies are focused on the reduction of fossil fuel consumption and increased use of renewable sources of energy [51].

As a response, and more recently, the notion of the “circular economy” (presented in Figure 2), as compared to the traditional “linear economy”, has gained attention to represent a strategic approach to sustainable development [52]. In general, while the linear economy is based on a take-make-dispose philosophy, the circular economy (which has the potential to save more than one trillion dollars per year globally [53]) approaches production by focusing on the reduction of waste throughout the product lifecycle by making use of the notions of recycling, reusing, and remanufacturing. The CE in general focuses on preserving the value, integrated materials, components, and products within a developmental framework that is sustainable [54].

4. Determination Methodology

Recall, that the purpose of this study is to present a definition of green aviation and formulate a conceptual model representing that definition. Figure 3 presents a schema that shows the six steps/sequences (Figure 3, left column) undertaken leading to the formulation of the definition and development of the framework. We also added relevant information regarding each step, on the right side of the figure, to make the figure more meaningful. Overall, Figure 3 shows that we start by using the aggregated and consolidated literature relevant to green aviation. The notes on the side give a summary of those findings and additional context. Based on the core articles directly addressing green aviation, a sample of private companies, and three articles in other fields talking about the notion of ‘green’, we utilized a thematic analysis to produce a set of concepts utilized (step 2). For step 3, we then composed an initial definition of green aviation and shared it via email with primary stakeholders from different areas (government, universities, research centers, organizations, and private firms). Step 4 entailed the formulation of the final definition after successive iterations and discussions with stakeholders. The final definition was then presented as part of a keynote speech at a green aviation conference, where the community at large was asked to provide any feedback, they may have (step 5). Finally, using all the information obtained so far, we developed and proposed a framework for green aviation.

4.1. Mixed Methods Approach

To formulate a definition of green aviation that would be applicable to different contexts, a mixed methods approach (MMA) seems to be the most reasonable one. Therefore, the MMA used in our study consisted of a thematic analysis (TA) of the literature and stakeholder feedback. Thematic analysis is a method that falls under the qualitative research family that primarily entails the encoding of text to identify, analyze, and report patterns. Thematic analysis has been widely used in various contexts and has been expanded and embedded in different analytical frameworks (such enhancing TA as an approach [55], qualitative healthcare research [56], analysis in the digital space [57], and qualitative data analysis software [58]).

Thematic analysis by itself has been misunderstood as a singular method that follows a series of steps which leads you to structured findings [59]. However, as elaborated by [60], TA can be considered as a combination of evaluative approaches with common and unique features representing the context employed to examine text/content in all its forms. The goal is to uncover, depending on the field being considered, thematic characteristics and results in a deeper understanding of the subject matter being studied [61,62,63,64,65].

Approaches to thematic analysis can be data- or theory-driven, in terms of coding orientation, capturing of semantic language and latent meanings, process of coding development and thematic formulation, and the relative flexibility vis-à-vis the theoretical frameworks entailing the study undertaken. Ref. [66] categorized thematic analysis methods into three broad types, namely “evidence for themes”, “conceptualized patterns”, and “topic summaries”. Going into details of these three categories is outside the scope of this study, however, ref. [66] provides a lengthy analysis of their development and use. Our approach fits the conceptualized pattern category, which is suitable for our purpose in as much as it focuses on exploring the researcher’s subjective interpretation and sense-making of the notion of green aviation [67,68].

4.2. Defining Green Aviation

As we have seen above, green aviation represents a multifaceted approach to transforming the aviation industry into a more sustainable sector. We distinguish at this point “Green Aviation” from “Sustainability”. So far, the notion of green aviation refers to initiatives that reduce the climate impact; however, these initiatives need to be sustained. As such, sustainability implies that there are other mechanisms to ensure that continuous climate impact reduction efforts are in place.

The term ‘Green’ has been utilized interchangeably with the concept of sustainability [69], where some have even used it loosely to imply net-zero greenhouse gas emissions. Yet, the literature does not provide any indication of a consensus regarding the meaning or definition of ‘green’ and ‘sustainability’. Overall, it seems that the term ‘Green’ is used to indicate a reduction of carbon emissions. Therefore, we find that many articles that study the reduction of carbon emissions in any context, such as improvement in aircraft engine efficiency, would tend to tacitly use the word green loosely, in the abstract or text, to express that such an initiative is good for the environment.

Ref. [7] associates ‘Green’ with emissions-free. However, the author does not further develop this notion of green and uses it to discuss the transition to a green global economy. NASA perceives green aviation as the pursuit of enhanced aircraft efficiency entailing the reduction of noise levels and GHG emissions [70]. In such interpretations, green aviation can be viewed within the scope of a sustainability ecosystem entailing organizations, inter- and intra-specific interactions, processes, and people.

Ref. [1] explains that ‘green’ refers to the environment characterized by climate-friendly development, energy conservation, and protection to reduce negative influences. Subsequently, ref. [71] refers to ‘Green Aviation Industry Sustainable Development’ as a strategy centered around two parameters, namely environmental protection and rational utilization of resources [72], acknowledging that it is influenced primarily by technological innovations, governmental climate mitigation policies, and organizational strategic planning [33,46,73].

4.3. Formulating the Definition

Consequently, we adapt the TQGAM system to entail three concepts representing important components that need to be in place for the realization of green aviation. We would like to note that even green aviation, as a construct, indicates a fixed goal, level, or stage that is attained; however, we stress that green aviation is more appropriately (and use it synonymously) referred to as the ‘greening of aviation’. In this case, the greening of aviation implies a state, a condition, and a level of maturity more representative of capabilities that are sustainable over time and space.

From an organizational perspective, a total quality green aviation management system consists of three dimensions: (1) an organizational climate impact maturity that represents the organization’s structure, governance, management, operations, culture, and performance; (2) continuous improvement capabilities which imply that the organization has to have strategic and change management systems in place; and (3) climate success which indicates that the organization must have in place some understanding of the impact it needs to make regarding climate change.

Our literature review identified 17 articles related to green aviation. Based on these articles, and reading through the entire text, we identified 8 relevant studies on green aviation.

Table 2. Selected definitions representative of how different areas view the notion of green.

	Source and Perspective	S	E	P
1	[74]: Green aviation takes account of the environmental footprint and focuses on minimizing greenhouse emission while still producing accurate results.	½	✓
2	[76]: Most literature addresses the concept of green at the level of energy consumption.			✓
3	[24]: Green aviation is more environmentally friendly and inclusive, as it not only produces the same results without increasing the cost but ensures that others can perform within their capacities.		✓	½
4	Green Airport Model [77]: The term “greening” used herein can be synonymous to “development” used by [77] to be broadly understood as an intentional effort to improve the carbon footprint of human beings.		✓
5	Passenger’s knowledge and attitudes [20]: Associates green aviation with the successful implementation of green solutions in the aviation industry, as a result from technological and scientific innovations as well as legal and political initiatives.		✓	✓
6	Strategies towards a more sustainable aviation [10]: Associates solutions towards greener aviation are realized via seven areas of solutions, namely operations, energy storage, propulsion systems, aerodynamics, structures, materials, and manufacturing processes.			✓
7	Greening aviation [28]: Authors conceptualize greening aviation in terms of decarbonization and the challenges associated with its operationalization.		✓
8	Ref. [75] defines green aviation as efforts to “achieve significant reductions in aviation’s environmental impacts through the adoption of low-emission aircraft technologies and sustainable aviation fuels.		✓	✓
9	AZEA: “The Alliance for Zero-Emission Aviation is a voluntary initiative that prepares the European aviation ecosystem for the transition to electric and hydrogen propulsion in line with the objectives of the European Green Deal”. (www.azea.com)		✓	✓
10	GlobeAir: “Green Aviation refers to the practices, technologies, and policies aimed at reducing the environmental impact of aviation. This includes decreasing greenhouse gas emissions and noise pollution and improving fuel efficiency.” (www.globeair.com)		✓	✓
11	From [78]: Green supply chains entail embedding environmental thinking into every element of supply chain management, including product design, material sourcing, manufacturing, delivery, and disposal.	✓	½
12	[79]: Green supply chains are not only about lowering environmental risks but about achieving profitability and market share through ecologically responsible practices.	½	½	✓
13	[80]: Green innovation connotes a series of innovative activities based on environmental friendliness and sustainable development.	½	½	½

S: Sustainability; E: Environment; P: Practice. ✓: Indicates full extent (½ indicates to some extent) at which the source addresses the three S, E, P areas.

shows these eight articles (rows 1 to 8 in Table 2) and how they dealt with the notion of green aviation. Moreover, rows 9 and 10 provide two examples of private companies in the area of green aviation, and rows 11–13 demonstrates how the notion of green is addressed in other fields, such as supply chain and innovation. None of these sources provide a definition. They make reference or comparisons to how they interpret it. For example, ref. [74] says that green aviation takes account of …, and [75] defines it as efforts to …, thereby avoiding a clear definition of what it is, and defer to what it achieves. It is worthwhile noting that [76] echoes similar findings to ours, that most of the literature addresses the concept of green at the level of energy consumption.

Furthermore, we tried to expand our search for the definition of ‘Green’ in other areas. The ‘Green Supply Chain’ and ‘Green Innovation’ have used these terms but remain silent on its definitions. An example of how they treat the notion of green is given in Table 2 for rows 11 to 13. We then decided to look even more broadly at organization and see how they may define the concept of green. Rows 9 and 10, in Table 2, show two examples of two organizations AZEA and GlobeAir who used the term green aviation on their website to explain what they do, their mission, or slogan. AZEA describes specifically their business in electric and hydrogen propulsion as a reference to the European Green Deal, while GlobeAir say that green aviation refers to …, and provide a small explanation with an additional sentence. Both still miss the mark for a definition.

The way we approached formulating the definition is as follows: (1) we proposed a definition that was elaborate and not precise (based on the above literature findings) with the purpose to engage stakeholders; (2) we emailed the definition to 40 founding members of the International Association for Green Aviation seeking their feedback; (3) we then considered the feedback of those who responded; (4) a new version of the definition that was more precise, based on the thematic analysis and the feedback from step 3, was formulated; and (5) the definition was presented in the International Conference on Green Aviation as part of a keynote speech to over 400 participants. At the end of the presentation, we extended our invitation to all for any comments, suggestions, or thoughts. The first proposed definition was:

Proposed Definition Iteration 1:

“Green aviation is the total quality integration management of Greenhouse gases mitigation practices including technological, organizational, behavioral, and regulatory practices within the aviation ecosystem, within a sustainability framework of continuous improvement, stakeholder engagement, economic wellbeing, and operational efficiency.”

After emailing the definition to the 40 founding members, we received five responses (by email, and some resulting in further back and forth discussions on different aspects). An example of a couple of the more important feedback, which was communicated to us as another alternative definition, is:

Feedback 1:

“Green aviation considers the environmental impact throughout an aircraft’s lifecycle, focusing on sustainable design, production, fuel use, operations, and disposal to minimize emissions, resource consumption, and ecological footprint across all stages.”

Feedback 2:

“IAGA, the International Association for Green Aviation is striving for a comprehensive sustainable aviation sector regarding environment, economy, and social wellbeing. Internationally coordinated activities and programmes will be designed in support to reduce drastically greenhouse gas emissions, use less fuel, reduce noise, and advance environmental friendliness throughout the entire product life cycle.”

The feedback was insightful in the sense that it allowed us to see the diverse perspectives on how the notion of green aviation is viewed. An important goal is that, as we progress from now on, we all need to agree on what green aviation means. This alignment is necessary to set up the foundation for future research and best practices. It is important to stress at this point that the definition must meet two criteria: (1) it should be devised in such a way to allow for the provision of TQGAM and CE, and (2) it should be generic enough to be inclusive to all contexts. Considering all the above, the second iteration for the definition, which was presented at the conference, is as follows:

Definition Version 2—Final:

“Green aviation is defined as the sustainable aviation practices to minimize the environmental impact and continuously improve social wellbeing.”

The second version of the definition was presented to over 400 conference participants. The presentation resulted in important discussions afterwards with a lot of buy-in from all stakeholders. Participants consisted of senior management from the private sector, the United Nations, universities, and regulatory bodies in aviation.

The goal of the definition is to unify all perspectives, such that any individual, organization or government can be aligned with the definition. In other words, the definition in and of itself is inclusive to any entity with an environmental goal. Therefore, as mentioned above, our thematic analysis seeks to identify conceptualized patterns of recurring themes, ideas, and perceptions. Repeated words, phrases, concepts, and practices are the primary indicator for recognizing conceptualized patterns. In the aviation sector (and probably the same in all other sectors), for our thematic analysis and community engagement, we observed that individuals, organizations, governments, and other stakeholders tend to commit (and focus) to a word, phrase, concept, or practice and (understandably) adopt it in a silo fashion as part of their green identity. Yet, none that we have seen is all inclusive. In that regard, our definition aims to unify all these conceptualized patterns.

The literature review provides a comprehensive view of how the aviation sector sees itself within the context of green aviation. For example, most of the themes regarding green aviation revolve around the notion of reducing carbon emissions, primarily in airlines and airports, in all areas and themes, as identified in

Table 3. Practices from TGBL. [Carbon Offsetting—list projects, waste management—refer to CE, carbon credits, airports].

Green Aviation—Airlines
A. Aerodynamics
1. Flow control|2. Morphing solutions|3. Noise reduction|4. Shape optimization|5. Aero-propulsion Integration|6. Novel configuration|7. Bio-inspired concepts
B. Operations
1. Fault detection systems|2. All-electric ground operations|3. Trajectory optimization|4. Regenerative descent|5. V-formation|6. Modifications to flight segments|7. Air-to-air refueling|8. Flight scheduling
C. Materials and Manufacturing
1. Bio-composites|2. Composites|3. Out of autoclave|4. Filament winding|5. Automatic tape layup|6. Automated fiber placement|7. Additive manufacturing
D. Structures
1. Structural optimization|2. Active load alleviation|3. Vibroacoustic control|4. Structural health monitoring
E. Energy
Drop-in biofuels|Liquid hydrogen|Hydrogen fuel cells|Structural batteries|Metal-air batteries|Lithium-based batteries
F. Propulsion
1. Hybrid-electric systems|2. Distributed propulsion|3. All-electric systems|4. Recuperated turbofan|5. Free piston turbofan|6. Water enhanced turbofan|7. Solid-oxide fuel cell turbofans|8. Flameless combustion|9. Inter-stage turbine burners
Source: For in-depth analysis and description, see [10].
Green Aviation—Airports
A. Noise Reduction
1. Noise protection barriers|2. Noise monitoring and prevention|3. Sound control near airport
B. Emission Reduction and Air Quality
1. Taxiing|2. Public Transport|3. Infrastructure emissions mitigation|4. Monitoring of GHG emissions|5. Website for viewing pollution levels|6. Low emissions vehicles|7. Measuring surface temperature changes
C. Energy Management
1. Energy consumption|2. Alternative and renewable energy sources use|3. Audit for unnecessary energy expenditures|4. Smart energy solutions|5. Low energy lighting
D. Water Management (Infrastructure facility integration)
1. Efficiency in water usage|2. Rainwater capture|3. Investment|4. Surface water capture and treatment|5. Infrastructure integrated water capture and treatment
E. Waste Management (Solid waste focused)
1. Collection|2. Storage|3. disassembly|4. Recycling|5. Reuse|6. Bio-disposables|7. Incineration facilities|8. Policies|9. Use of no-packaging products|10. Waste sensitive contracts with partners|11. Have manual
F. Biodiversity Conservation and Land Use
1. Natural habitat preservation|2. Protection against animal invasion|3. Soil permeability|4. Prioritize natural lighting|5. Recreational practices|6. Wildlife reporting and management|7. Land use|8. Use space with least environmental impact
G. Cost and Economy (Policy oriented)
1. Control of environmental impact cost|2. Financial results made public| 3. Training|4. Focus on wellbeing and safety|5. Customer quality centric|6. Promote economic growth|7. Encourage stakeholders for environmental friendliness|8. Penalties for violators
H. Quality of the Internal Environment
1. Ventilation|2. Thermal comfort|3. Lighting|4. Noise
I. Transport and Vehicle Control
1. Parking|2. Reduce transportation|3. Vehicle use optimization|4. Sustainable fuel
J. Social and Cultural
1. Community contribution|2. Accessibility|3. Health and wellbeing|4. Preservation of the neighborhood
Source: For in-depth analysis and description, see [77].

below. Even when it comes to passenger’s perceptions and participation in reduction of their environmental footprint, it always manifests in terms of carbon emissions. Dispersed studies identify their greenness in terms of environmental impact/protection, or mitigation policies.

Considering the literature first, then the email correspondences, and finally the feedback from the proposal of the definition in the conference, we aggregated all the concepts and consolidated them into categories (elaborated in the following section) that construct the definition. The responses from different stakeholders did not have an influence on the identification of the themes or the formulation of the definition per se. The goal in attempting to engage stakeholders is to discuss, clarify, and consolidate ideas and themes that will be used to create the definition. At first, the stakeholders’ feedback resulted in important revisions to the definition. All subsequent feedback resulted in less refinement to the definition, to the point that most feedback from the conference had already been incorporated into the definition and we simply needed to bring that to the attention of the stakeholder. This process only took five iterations to converge with the definition presented above.

The coding of the themes was grouped into concept categories, namely sustainability, environment, and practices. All studies, replies to our email, and feedback from the conference fall under one of these categories. Now that we have wrapped the definition from conceptualized themes into a short, concise, and inclusive/unified concept, we shall unwrap it to provide insights into its application and elaborate on its interpretation.

4.4. Interpreting the Definition

The definition of green aviation addresses the organizational ecosystem, the environment, and people’s wellbeing, as shown in Figure 4. It is generic enough to ensure a balance between the survivability and the adaptability of the sector economically and otherwise, while focusing on environmental impact with a future continuous goal (with no achievable metric/number) ‘to minimize’ and keeping in mind the notion of continuous improvement (which is core to total quality management) of people and society.

Therefore, the notion of green occurs at the intersection between sustainable efforts, environmental focus, and best practices, such as:

• ‘Environmental impact’ affects all types of work in the aviation sector from manufacturers (aircrafts lifecycle, SAF production, etc…), airlines, airports, services, and governments/regulators.
• ‘Environmental’ is inclusive of CO₂ and all greenhouse gases (NO₂, CH₄, N₂O, Heo, O₃, HFCs, PFCs, and SF₆), noise, contrails, waste management, water management, etc…
• Practices imply efforts, initiatives, programs, policies, etc… (see Table 3 for airlines and airports), and can also include carbon offsets (see

  Table 4. Carbon offsetting projects.

  	Carbon Offsetting Practices
  1	Renewable Energy	Such projects are the most popular and include solar, wind, and hydroelectric power. These projects, after making up for their own carbon footprint related to their production, produce net carbon emission reduction effects [41].
  2	Blue Carbon	Blue carbon projects focus on carbon stored in coastal, marine, seagrass, and peatland ecosystems. These hold substantial amounts of carbon stocks and credits are awarded for the greatest amount of storage. Blue carbon projects aim to avoid degradation of coastal ecosystems, restoring mangroves, marshes, and seagrasses, enhancing the growth of kelp and shellfish, and the restoration of peatland vegetation.
  3	Land Management	Projects that focus on land management entail the enhancement and/or preservation of agricultural and wetlands natural health. These include sustainable and regenerative agricultural practices that target soil health, such as limiting soil disturbances (tillage), fertilizer use strategies, livestock management, and crop rotation. These practices target the minimization of GHG emissions coming from fertilizers and methane because of livestock. Spinoff benefits include improved soil health, water management, and air quality.
  4	Water Management	This includes projects which aim to solve the supply of clean water to households. This is especially applicable in rural areas. In doing so, water does not need to be boiled and consequently reduces carbon emissions.
  5	Waste Management	These projects primarily entail the capturing of methane and either destroying it clean or using it as a reliable energy source. Methane is captured because of landfill waste decomposition. Waste management has the highest applicability and impact in local communities with additional benefits of less pollution and unpleasant smell.
  6	Forestry	Whether it is forestation, reforestation, or improved forest management, these projects focus on forestry practices to enhance the natural forestry ecosystem, natural regeneration, and improve carbon sequestration. These types of projects span from business practices in organizations like logging to pests and fires management. (e.g., selective logging, rotation period optimizations, improved tree thinning management, and protection and controlled burns).
  7	Direct Carbon Removal	These projects include the use of technologies to capture carbon dioxide from the atmosphere directly and either store or reuse it. Direct carbon removal is not feasible yet on a large scale and is very costly to implement. Advances such as biochar and carbonated cement are on their way as innovative solutions in this area. This may also be referred to as sequestration of CO2.
  8	Biomass Carbon Removal	Carbon dioxide can be removed via the conversion of biomass into forms that can be stored and removed in the long-term.

  ).
• Social well-being addresses shared value creation, education, standards of living, health (example aircraft noise), etc…
• Minimize is forward looking vis-à-vis, for example, implementation of policies/regulations, and carbon neutral. The notion of minimizing is better than setting a hard target as it allows for strategic planning based on context. The importance is that part of the continuous improvement includes the continuous reduction of carbon emissions to a minimum which can then be set to policy, targets, or zero.

The concept of sustainability in the current context is best understood and addressed from multiple perspectives that integrate the three dimensions of environment, social, and economy (

Table 5. Sustainability elements from TGBL.

Elements	Description	Recent References
Environmental	This entails the management of resources (particularly in land and water) and maintaining ecological integrity. These are primary areas for protection and for environmental sustainability. Moreover, sustainable use of energy is very important and includes usability, availability, cost, and environmental impact.	[81,82]
Social	Social sustainability focuses on overall community wellbeing, including equity, social engagement, and stakeholder management. Issues in this area include gender equality, lifestyle, local context, community dynamics, education, and innovation as central themes of study.	[81,83,84]
Economic	The long-term viability of the organization is essential, which is only secured by financial stability and profitable practices. This implies that sustainability elements need to be part of strategic plans and business models, and that an organization’s stakeholders are fully aware and understand the relationship between organizational ecosystem and sustainable dimensions/elements. What we are seeking is a balance of economic growth and sustainable practices.	[85,86]

). These three dimensions are in line with the triple bottom line framework used in organizational behavior and which elucidate the primary components of what makes sustainability sustainable. This is true, because the elements of sustainability are interconnected at multiple depths where it encompasses notions of stewardship, social equity, and economic viability (including profitability).

Moreover, sustainability is only attained according to the level of integration across these three dimensions. The hierarchical relationship among various sustainability factors emphasizes that effective governance and stakeholder engagement are critical for developing a comprehensive sustainability framework [87]. This interconnectedness is echoed by other researchers highlighting the importance of understanding a deeper level the interconnectedness between economic, environmental, and social dimensions over time [88].

Table 6. Environment from TGBL.

GHG	Description	Emissions	Recent References
CO2	Carbon Dioxide: From fossil and biomass fuels. Can last for a long time in the atmosphere.	63% of total GHG	[89,90,91]
CH4	Methane: Is around 25 times more global warming potential than CO2 over a period of a century. Its sources include coal, oil and natural gas production and transport, and agricultural and livestock practices.	15% of total GHG	[90,92,93]
N2O	Nitrous Oxide: Results from agriculture (during fertilization process) and industrial activities, fossil fuels and solid waste. It is around 300 times more than CO2 in terms of its global warming effect over the period of a century.	-	[92,93,94]
H2O	Water Vapor: Water vapor in the atmosphere is considered a greenhouse gas. It is very abundant and created by natural conditions and not human activities. Its role in global warming is its amplification effect on other GHGs	-	[95]
O3	Ozone: As a secondary pollutant, volatile organic compounds and nitrogen oxides react with sunlight to create ozone.	-	[95]
XFCs	Fluorinated Hydrocarbons: Synthetic gases such as hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6) result from their industrial applications.Despite the lower emissions relative to CO2, CH4, and N2O, they can have 1000 s of times more effect on global warming that may last for a long time in the atmosphere.	-	[93,95]

summarizes the primary greenhouse gases, their descriptions, and their emissions, supported by relevant scholarly references.

The understanding of these greenhouse gases is critical for environmental protection activities aimed at mitigating climate change. Each gas has distinct sources and impacts, necessitating targeted strategies for emission reduction. It is worthwhile noting that some GHGs, although much less than CO₂ in the atmosphere, still have a larger impact, such as methane and nitrous oxides (see Table 6).

5. Discussion and Conclusions

The literature on sustainability in aviation has become mainstream, especially after the release of the Carbon Offsetting and Reduction Scheme for International Aviation. All aviation stakeholders have been trying to make sense and implement the basket of measures for carbon emissions reduction. With this increased interest, the concept of ‘Green Aviation’ recently appeared in the literature and is starting to take hold in scientific work. As such, the increasing research in the green aviation arena does not show any consensus of what the term green implies. Many interpret the meaning of green aviation to align it to their central theme or focus of study, resulting in many different variations of what green aviation entails, but none identifies what it is. To fill this gap, this paper has made an attempt to provide a definition for ‘Green Aviation’, that would be representative of all the notions discussed in the literature, yet generic enough to account for all specific applications and all stakeholder’s activities.

Before we embarked on the definition methodology, the literature provided insights into the elements of sustainability for aviation, and that included organizations, passengers, the environment, and professionals. Therefore, we decided to underpin our approach to two very important theoretical frameworks, namely the total quality management and circular economy frameworks, because both engage all the elements of sustainability. We kept those two theories in mind while we progressed in the development of the definitions.

In order to come up with the definition, we followed a two-step approach. First, we conducted a comprehensive literature review and applied a thematic analysis methodology to extract common meanings for the term. Then we distributed the definition to 40 professionals in the area of sustainability and green aviation and solicited feedback on the first attempt at a definition. After a few iterations and offline discussions, a modified more accurate and converging definition was formulated, which was then presented in a green aviation conference to over 400 professionals, and to whom we asked for feedback and comments. Following the conference, the definition was ‘frozen’ and presented herein as follows:

Green aviation is defined as the sustainable aviation practices to minimize the environmental impact and continuously improve social wellbeing.

The definition was then elaborated in depth to demonstrate its power of explanation, and its alignment with existing knowledge and research in the area. As the definition delineates sustainability, practices, and the environment, we provided details to what each one of those dimensions entail.

In addition to the rigorous approach to develop a unified, comprehensive, and inclusive definition for green aviation, our study analysis also resulted in the consolidation of the elements (obtained by interpreting the definition’s components) and mapping them into the green aviation framework components. The framework components are detailed in Table 3, Table 4, Table 5 and Table 6 showing the different categories that organizations can use for assessing and planning their green aviation initiatives. The components, which are practices, sustainability, and environment (the triple bottom line for green aviation), independently identify the different areas that firms can participate in to reduce their environmental impact. The categories for each component, listed below, represent more focused opportunities that different stakeholders can commit to, depending on their strategy, function, and purpose. By engaging in all three components, organizations would then be working towards different levels of being green. The components and their categories are as follows:

• Practices − Airlines = aerodynamics, operations, material and manufacturing, structures, energy, and propulsion (Table 3).
• Practices − Airports = noise reduction, emissions reduction and air quality, energy management, water management for infrastructure facility integration, waste management for solid waste, biodiversity conservation and land use, cost and economy from policy perspective, quality of the internal environment, transportation and vehicle control, and social and cultural aspects of airport business (Table 3).
• Depth of sustainability = environmental, social, and economic (Table 5).
• Extent of environmental impact: CO₂, CH₄, N₂O, H₂O, O₃, and XFCs (Table 6).
• Carbon offsetting: renewable energy, blue carbon, land management, water management, waste management, forestry, direct carbon removal, and biomass carbon removal (Table 4).

The TGBL framework can be operationalized (for example, in its simplest form) by considering one simple parameter for each category: extent of engagement (none, low, moderate, and high). A score is then assigned for each category, then normalized to the component, and finally plotted on a radar chart to provide a visual indication of the organization’s green aviation state. Much more sophisticated models can be created using this framework, and this line of inquiry presents many opportunities for future research.

Throughout the study process, namely the literature review and engagement with stakeholders, we found/observed the following: (1) Interest in the notion of green aviation is increasing in momentum, because it represents a wholistic perspective of environmental impact and sustainability; (2) Stakeholders are accepting the new reality to adopt and adapt new technologies whether they agree with it or not. A good example is sustainable aviation fuels where supply chain partners are starting to work with each other to solve associated challenges, such as the cost of its deployment and identifying pathways for its implementation; (3) International non-government organizations are being accepted by the aviation sector as facilitators to inter-firm collaboration. This is observed in the increasing INGO support by these firms; and (4) Specialized firms, such as electric airplane, aviation sensors, big data aggregators, and battery manufacturers, have also realized that they have a larger role to play in the green paradigm identified by the TGBL framework.

This study is foundational, as it provides a framework for future research to focus on different areas of green aviation and present their contributions in a standardized and systematic fashion making it easier for researchers to build upon each other’s works and open new venues of collaboration. Some of the future research opportunities may entail the following:

• Researchers can position their research work and contribution based on the definition proposed herein. Table 3, Table 4, Table 5 and Table 6 can provide details to the area of their research.
• As a research community in the green aviation sector, this study can seed future research towards the development of a green aviation index.
• Ref. [77] and our study herein provide the foundation for research on the assessment of green airlines, manufacturers, etc.
• Future research is needed in green aviation by the development of case studies utilizing our definition and framework.
• Many more specific opportunities for future research are suggested by this study, such as:
  • What are the best practices for green aviation?
  • What are the impacts of the greening of aviation on the organization?
  • Green aviation performance metrics.
  • Issues regarding the implementation of environmental policies.
  • Sustaining the Green in green aviation organizations.
  • What is the understanding of different stakeholders vis-à-vis the notion of green in aviation?
  • Organizational maturity to develop and sustain green initiatives.
  • Readiness of managers and leaders for the implementation of green aviation programs.
  • The Green Employee, Manager, Leader—A badge of honor.

Furthermore, our work provides a comprehensive venue and actionable framework for professionals to use in their practice. More specifically, professionals in the airlines, airports, regulation organizations, government and non-government organizations, and other institutions, can utilize the assets in this manuscript to assess their context regarding their role in green aviation (as per the definition), their plans regarding their organization’s environmental impact, and the integration of the elements elaborated herein into their strategic plan for continuous improvement. The definition brings forth three operational and strategic elements and two initiatives (one internal and the other external) for practitioners to consider. The elements include sustainability, environmental impact, and practices. These elements are hierarchical, allowing practitioners to revisit their practices in terms of processes at the operational level (short-term), target specific environmental impacts (i.e., carbon emissions reduction, energy conservation, or carbon offsetting) as part of their tactical decisions (mid-term), and integrate a sustainable infrastructure as part of their strategic plan.

The two primary initiatives found in the definition are continuous improvement and social wellbeing. The organization internally, as part of being green, must develop a culture of change and evolution to enhanced and higher levels of efficiency and effectiveness. These initiatives are related to the notion of organizational maturity which usually consists of five levels. Moreover, the practitioner needs to ask their organization about their role and contribution to society and the wellbeing of its citizens. As an example, practices that can translate into aircraft noise reduction or an awareness campaign regarding the use of sustainable aviation fuels. The details of these elements and initiatives are found in Table 3, Table 4 and Table 6, and can be used by practitioners to build a green aviation portfolio. With this portfolio, practitioners can identify gaps, opportunities for improvement, and pathways to realize their green strategic plan.