# NFT-Based Framework for Digital Twin Management in Aviation Component Lifecycle Tracking
## 3 Results
### The Workflow for Technical Documentation Using NTF-Based Technology  
The workflow for technical documentation using an NFT-based system presents an approach to creating, reviewing, approving, and managing technical documents in the aviation industry (Figure 10) to ensure the authenticity, traceability, and secure management of critical technical documentation throughout its lifecycle.  
The process begins with document creation, where a new technical document is initiated. At this stage, a unique NFT is created to represent the document. This digital token serves as the document's immutable identifier and will store all subsequent changes and approvals throughout its lifecycle.  
Following creation, the document enters the internal review phase. The NFT is updated to reflect that the document is under review, including details such as reviewers and review dates. Version control is applied throughout this process, managing different iterations of the document as it undergoes revisions.  
After internal review, the workflow reaches an approval decision point. If not approved, the document goes through revisions, with each revision recorded in the NFT, maintaining a clear audit trail of changes. If approved, the document moves to the regulatory approval stage.  
During regulatory approval, the NFT is updated to indicate that the document is undergoing external regulatory review. This stage is crucial for ensuring compliance with aviation industry standards and regulations.  
The regulatory approval process leads to another decision point. If not approved, the document enters the address regulatory feedback stage, where necessary changes are made based on regulatory input. These changes are meticulously recorded in the NFT. If approved, the document proceeds to publication.  
At the publication stage, the NFT is updated to reflect the document's final approved status, version number, and publication date. This creates an official, verifiable record of the document's release.  
Post-publication, the document enters the distribution phase. The NFT is updated with information about how and to whom the document is distributed. This is closely tied to access control, which manages who can view or modify the document, with all access permissions and activities recorded in the NFT.  
Compliance tracking runs parallel to these processes, monitoring and recording in the NFT how the document adheres to relevant regulations and standards throughout its lifecycle.  
User access represents the stage where end-users interact with the published document. The NFT continues to play a crucial role here, recording access patterns and ensuring users are viewing the most up-to-date version of the document.  
The workflow includes a decision point to determine if an update required. If an update is necessary, the process cycles back to the document creation or internal review stage, initiating a new version of the document. This update process is carefully managed through version control, ensuring that all changes are tracked, and previous versions are preserved.  
If no update is required, the document remains in active use, with the NFT continuing to record its usage and status.  
Figure 10: Flowchart of the workflow for technical documentation.