Airports have taken centre stage in the fight against the ongoing COVID-19 pandemic, and adoption of technologies has been instrumental in helping airport operators to mitigate operational and health concerns relating to the pandemic. A novel framework for the adoption of Industry 4.0 technologies was developed based on the insights gathered from an industry survey of 102 airport operators and managers around the world and 17 semi-structured interviews. The framework provides a ‘three-proof’ approach (proof of technology, proof of operations and proof of business) to guide airport operators in their decision-making process in adopting Industry 4.0 technologies in airports. This framework is further verified through a case study of the technology implementation efforts of a leading Asian airport. One Sentence Summary: A novel framework and case study for the adoption of Industry 4.0 technologies in airports Keywords: Airport 4.0; Airport; Industry 4.0; Technology; Technologies; Adoption; Digital Transformation; Digitalisation; Aviation 4.0; Aviation; Aerospace; Robotics; TAFA Framework; Framework; Case study; Interviews; Use cases. 1. Introduction Traditionally, airports have served as gateways to the world to connect families, businesses, cultures and economies. In the ongoing COVID-19 pandemic, countries have taken unprecedented measures to close their international borders and to implement strict testing and quarantine regimes in airports to identify passengers who may have contracted the coronavirus. Airports have since evolved into crucial gateways for countries to stem the spread of COVID-19 and has thus presented a fresh set of challenges for airport operators. Based on a recent industry survey (Tan & Masood, 2021b), airport operators faced increasing pressure to implement safe distancing measures and periodic sanitisation protocols to provide a safe travelling environment (ICAO, 2020). Despite a marked reduction in passenger volume compared to pre-COVID years, manpower shortage is a pertinent issue faced by airport operators to facilitate airport Tan, J.H. and Masood, T. (2022). “Airport 4.0 – Technology Adoption Framework for Airports (TAFA)”, pp. 1-29, pre-print, engrXiv, 05/01/2022. Page | 3 operations while mitigating health and safety concerns relating to the pandemic. These has culminated in a greater push to adopt Industry 4.0 (I4.0) technologies in airports to resolve these challenges. Technology adoption is not a new phenomenon for airports. According to a recent structured literature review (SLR), airports have increasingly adopted I4.0 technologies as part of their digital transformation journeys with data mining and analytics being the most widely-adopted technology among other I4.0 technologies identified (Tan & Masood, 2021a). However, the adoption of I4.0 technologies is marred by several technological, organisational and environmental challenges, with organisational readiness being one of the most statistically significant factor in influencing the success of technology adoption in airports (Tan & Masood, 2021b). The research presented in this article is aimed at investigating the following overarching research question: “How can airport operators or managers develop airports of the future using I4.0 technologies?”. While there are technology adoption frameworks such as the TOE framework and DOI theory that are most prevalently referenced in academic literature to study technology adoption in firms (Oliveira & Martins, 2011), there is a lack of generic criteria for airport operators to assess the feasibility of I4.0 technologies for adoption in airports. Sohn et. al. (2013) developed a preliminary smart airport framework to establish an integrated view of the use of smart technology to improve passenger service and airport resource management but has also highlighted the need to extend the strategic framework to include airport operations. Due to the lack of a technology adoption framework to complement the digitalisation strategy of airports, a novel Technology Adoption Framework for Airports (TAFA framework) was developed. The TAFA framework serves to guide airport operators in their digital transformation process, particularly in the adoption of I4.0 technologies in the airport. Furthermore, a case study was developed to validate the use of the TAFA framework in the context of the technology implementation efforts of a leading Asian airport. The rest of this article is structured as follows. Section 2 provides background and literature review on Airport 4.0. Section 3 presents research methodology. Section 4 presents the TAFA framework and its components. Section 5 presents a case study of a leading Asian airport using the TAFA framework. Section 6 discusses some of the key contributions of the TAFA framework and case study to industrial practice and academia as well as limitations and possible future work. Section 7 concludes the article. 2. Airport 4.0 2.1 Definition of Airport 4.0 Establishing clear definitions provide the fundamental starting ground for research. Based on the SLR, the terms “Aviation 4.0” and “Airport 4.0” were mentioned briefly in a handful of papers. The term Aviation 4.0 captures the paradigm shift in the aviation industry through the incorporation of I4.0 technologies (Valdés et al., 2018). However, as pointed out by Valdés et al. (2018), Aviation 4.0 is mainly related to aerospace manufacturing processes, with minimal or little reference to airline or airport operations. In this regard, the term Airport 4.0 is more appropriate to capture the new digital age of airports. Out of the papers reviewed, only 4 papers mentioned the term “Airport 4.0” in the title, abstract, list of keywords or the general content (Table 1) (Tan & Masood 2021a). Tan, J.H. and Masood, T. (2022). “Airport 4.0 – Technology Adoption Framework for Airports (TAFA)”, pp. 1-29, pre-print, engrXiv, 05/01/2022. Page | 4 Both Felkel et al. (2017) and Koenig et al. (2019) discussed applications involving data analytics and sensor technologies. Zaharia & Pietreanu (2018) emphasised data analytics as a core capability of Airport 4.0 and illustrates a range of technologies that support the objectives of improving efficiency of airport operations, enhancing passenger journey and creating ancillary revenues. From these papers, it is evident that the term Airport 4.0 is used as a broad term to imply advancement and adoption of technologies in airports, with a weak reference to the associated term “Industry 4.0”. Furthermore, considering the lack of academic publications that mention Airport 4.0, it can be concluded that there is no general definition for the term “Airport 4.0” in academic literature, unlike the term “Industry 4.0” which has been widely defined and discussed (Fettermann et al., 2018). Consequently, the I4.0 technologies that are important for future airports are not explicitly captured in literature. Tan, J.H. and Masood, T. (2022). “Airport 4.0 – Technology Adoption Framework for Airports (TAFA)”, pp. 1-29, pre-print, engrXiv, 05/01/2022. Page | 5 Table 1: Review of "Airport 4.0" literature (Tan & Masood 2021a). Tan, J.H. and Masood, T. (2022). “Airport 4.0 – Technology Adoption Framework for Airports (TAFA)”, pp. 1-29, pre-print, engrXiv, 05/01/2022. Page | 6 2.2 Frequency and challenges of I4.0 technology adoption in airports This section outlines the frequency of adoption of I4.0 technologies as well as the key challenges faced in their adoption. Figure 1 illustrates the frequency of adoption across the different functional categories of I4.0 technologies in airports based on the papers reviewed. Some papers reviewed discussed more than one category of I4.0 technology and these are counted accordingly. From the figure, data analysis and processing is the most prevalent functional category of I4.0 technology that is adopted in airports. This is consistent with the observation from Mullan (2019) that the airport environment is rich with data that is generated across all stages of the passengers’ journey. Also, since the SLR is focused on the airport which has no manufacturing operations, it is not surprising to find no reference to additive manufacturing in the literature reviewed. Even though cloud computing is rarely discussed in the papers reviewed, it is likely to be underrepresented in this frequency analysis. This is because the functional category of cloud computing consists mainly of backend services and infrastructure that enables the remote processing of data and facilitates data storage and applications (Fettermann et al., 2018). Thus, even though cloud computing is not explicitly discussed in the papers reviewed, it is likely to be a key technology that enables other I4.0 technology applications in the airport, such as data analytics and the implementation of SSTs (Yau & Tang, 2018). Table 2 summarises the key challenges faced in adopting I4.0 technologies in airports from the papers reviewed in the SLR. The various challenges are grouped into three main categories (technology, organisational and environmental). From the table, it is evident that technological challenges were most frequently discussed in literature, with specific technology limitations relating to the I4.0 technologies being the most prevalent challenge faced. The I4.0 technologies were adopted across various functions in the airport, namely: passenger handling services, commercial services, airside operations, air traffic control and management, airport planning, design and construction, airport logistics and airport security. Figure 1: Frequency of I4.0 technologies appearing in literature Tan, J.H. and Masood, T. (2022). “Airport 4.0 – Technology Adoption Framework for Airports (TAFA)”, pp. 1-29, pre-print, engrXiv, 05/01/2022. Page | 7 Table 2: Challenges in adopting I4.0 technologies in airports 2.3 Results and analysis of a Recent Industrial Survey The results and analysis of a recent industrial survey of airport operators and managers (Tan & Masood 2021b) provides current state of adoption of I4.0 technologies in airports. 2.3.1 Success factors for adopting I4.0 technologies in airports In the survey questionnaire (Tan & Masood 2021b), airport operators were provided with a list of I4.0 technologies that were identified from the initial literature review (Tan & Masood 2021a). From this list, airport operators had to identify the technologies which they perceive to be important for future airports based on their airport management experience. Thereafter, they were tasked to indicate the technologies which are currently implemented within the airports that they operate based upon their selections. Two scores were computed based on how often the technology was selected in the survey in percentage terms. Implementation score reflects how often the particular I4.0 technology is implemented in current airports while importance score reflects the relative importance of the I4.0 technology for future airports. The implementation scores were calculated based on how often survey participants have indicated that the I4.0 technology was implemented in airports currently. The importance score was calculated based on how often the survey participants have indicated that the technology was important for future Tan, J.H. and Masood, T. (2022). “Airport 4.0 – Technology Adoption Framework for Airports (TAFA)”, pp. 1-29, pre-print, engrXiv, 05/01/2022. Page | 8 airports. Figure 2 provides a snapshot of the current state of adoption of I4.0 technologies in the airport based on their importance and implementation scores. The I4.0 technologies shown in the top-right quadrant (green) are considered to be both important and are widely implemented in airports currently. Figure 2: Implementation and importance scores of I4.0 technologies in airports (Tan & Masood 2021b) 2.3.2 Success factors for adopting I4.0 technologies in airports In the survey questionnaire (Tan & Masood 2021b), airport operators were also tasked to identify key success factors for successful adoption of I4.0 technologies in the airport from a pre-defined list of success factors based on literature review (Tan & Masood 2021a) and interview inputs. For airport operators who have indicated that the airports they manage do not have any past successes in implementing I4.0 technologies, their responses in this category were excluded. Thereafter, they were tasked to rank the success factors based upon their selections. Two sets of data were generated from the data collected: (i) Frequency: Percentage of how often the factor was selected by survey respondents to be a success factor for I4.0 technology adoption; and (ii) Average normalised rank: Based on the ranking that survey respondents have indicated for their selection of success factors, normalisation was carried out to account for the different number of success factors that may have been selected by different respondents. Thereafter, the average of the normalised ranks for each success factor was computed. The normalised rank for each success factor can range from 1 to 10, with 1 being the most important success factor. Figure 3 illustrates the various success factors mapped according to their frequencies and average normalised rank in the survey. The success factors in the top-right quadrant (green) were most frequently selected by survey respondents and also ranked highly in terms of their importance for I4.0 technology adoption in airports. Tan, J.H. and Masood, T. (2022). “Airport 4.0 – Technology Adoption Framework for Airports (TAFA)”, pp. 1-29, pre-print, engrXiv, 05/01/2022. Page | 9 Figure 3: Frequencies and average normalised ranks of success factors (Tan & Masood 2021b) 2.4 Research gaps and objectives This section outlines the research gaps that were identified from the literature. Research objectives (ROs) are then proposed based on the research gaps (RGs). 2.4.1 No clarity on I4.0 technologies that are important for future airports (RG1) From the SLR (Tan & Masood 2021a), it is evident that the term “Airport 4.0” has been loosely adopted in literature to suggest an ongoing digitalisation trend in airports that is in line with I4.0. Furthermore, not all the functional categories of I4.0 technologies identified by Fettermann et al. (2018) are directly relevant to airports as the term I4.0 is mainly used in a manufacturing context. This observation is consistent with Jaffer & Timbrell (2014) who opined that academic researchers have yet to explore the strategic use of digital technologies in the context of an airport and analyse their impacts on customer experience. Furthermore, the papers reviewed focused largely on the implementation of technologies for day-to-day operations to improve operational efficiency and enhance passenger experience (Kovynyov & Mikut, 2019) and have little