Blockchain technology offers a promising solution for decentralized data sharing and communication among IoT devices. The decentralization aspect of blockchain technology has made it a popular topic for integration with IoT systems, including UAVs. Therefore, the use of blockchain technology in UAV systems has led to the growing interest of researchers, particularly in swarm UAV systems, where decentralization is crucial for ensuring safety and continuity. This study proposes a new data management model that integrates blockchain technology into UAV systems, with a particular focus on swarm UAV systems. By leveraging the decentralized structure of blockchain, the proposed system offers robustness against tampering and irreversibility, ensuring secure data transfer between UAVs and decentralized processing. Especially for mission plan and command upload operations, blockchain enables the distribution of critical information to all UAVs in the system. A use case scenario is also presented to demonstrate the effectiveness of the proposed model in controlling and managing real-world problems.