Communication is critical in the military sector where the integration of sophisticated tools becomes crucial to maintain operationality and flexibility. This paper investigates the integration of blockchain technology in military communications, focusing on a blockchain-based Short Message Service (SMS) application for the Portuguese Air Force. The aim is to enhance security, reliability, trust, and flexibility in military communication systems. A comprehensive methodological approach was utilized, based on the Design Science Research, incorporating an extensive literature review, an exploratory study of various blockchain solutions, and the development of a conceptual framework for the SMS application. Findings reveal that the application successfully addresses crucial aspects such as secure transmission, data integrity, user anonymity, and compliance with regulations like GDPR. The discussion highlights the transformative potential of blockchain in military contexts, emphasizing improved operational efficiency and secure data handling. In conclusion, blockchain technology is decisive in advancing military communication methods, offering a model that can be adapted to other defense sectors. This study contributes to the theoretical understanding of blockchain in military applications and provides practical insights for its implementation in secure communication systems, using Hyperledger.