In this paper, we have proposed Architecture Development methodology which can connect both operational view and system view. The Functional Architecture can connect both user and developer, and it is located between Activity analysis and System analysis. We suggest the new architecture methodology using the Functional Architecture and it provides effect to analyze the connection between user(military) and developer(enterprise) in Defence R&D and the new Architecture with the feedback analyze activity on a point of system view and the new architecture make the functional architecture.