# NFT-Based Framework for Digital Twin Management in Aviation Component Lifecycle Tracking
## 1 Introduction
### Related Work
Digital twins enable real-time monitoring of components and allow for predictive insights, which are essential for proactive maintenance in a field where unplanned downtime carries high safety and financial costs [55; 56]. Meanwhile, NFTs provide immutable, blockchain-based records that ensure each component's history is preserved without risk of tampering or data loss--a crucial capability in an industry where data integrity is paramount for regulatory compliance and operational transparency. In the field of asset lifecycle management, concepts such as digital twins, digital shadows, and digital threads are often discussed interchangeably. However, each term has a specific meaning and application, particularly in domains where real-time data accuracy and interoperability are critical factors [57]. Understanding these distinctions is essential to accurately evaluating existing works and the specific value that digital twins can bring to aviation. A digital shadow refers to a representation of a physical asset that receives data updates from the asset, but the data flow is unidirectional--from the asset to the digital model [58]. This means that a digital shadow provides a snapshot of the asset's current state based on recent data but does not enable any control or feedback from the digital representation to the physical asset [59]. Digital shadows are often used in monitoring systems where data integrity is important, but real-time interaction is not required [60]. A digital twin, on the other hand, represents a fully synchronized virtual model that not only mirrors the physical asset in real-time but also allows for bidirectional data flow, enabling interactions between the digital and physical entities [61]. In aviation, this means that digital twins of components or systems can be used not only to monitor real-time conditions and predict maintenance needs, but also to directly influence operations, make adjustments based on simulations, or inform maintenance scheduling dynamically [62]. The interactive nature of digital twins allows for more advanced predictive maintenance and operational optimization, which are crucial in highly regulated and safety-focused domains such as aviation [63]. A digital thread serves as a continuous chain of data and information that spans the entire lifecycle of an asset, from initial design to retirement [64]. It enables seamless data flow across all stages, departments, and stakeholders, creating a unified data structure [65]. In aviation, digital threads support lifecycle traceability, which is critical for regulatory compliance and safety [66]. By using these distinctions, we can see that many existing works referenced in this paper fall under the category of digital shadows, as they focus primarily on data collection and monitoring without enabling bidirectional interaction or predictive control. However, true digital twin applications in aviation, such as those deployed by Airbus Skywise [20] and Lufthansa Technik Aviatar [19], demonstrate the potential of interactive digital models to drive real-time decision-making and operational efficiencies. This paper adopts a digital twin perspective, emphasizing the need for interactive, synchronized models in component lifecycle management, while recognizing the complementary roles that digital shadows and digital threads can play in a comprehensive digital ecosystem. In this paper, digital twin technology refers to a comprehensive framework encompassing the architecture, interfaces, and guiding philosophy for creating and managing digital replicas of physical aviation components. Together, these elements provide a robust, interactive platform that ensures traceability, real-time monitoring, and lifecycle optimization of aviation components, meeting the industry's high standards for safety, reliability, and operational efficiency.