Unmanned aerial vehicle (UAV) networks offer enormous potential in civil, commercial, and military applications. As network sizes become large, the communication of UAV networks poses serious cybersecurity challenges. One solution for providing a secure, scalable communication mechanism is to integrate blockchain in the peer-to-peer UAV networks. Blockchain provides a way for multiple entities to communicate securely in a decentralized and cooperative manner. Because blockchain is primarily used for preventing double-spending in cryptocurrency, it lacks methods to secure communications in a network. Specifically, this paper proposes a novel consensus-building mechanism for securing communications in a UAV network, integrating blockchain with public key cryptography method Elliptic Curve Diffie-Hellman and one-time pad encryption method.