Presolicitation notice from the Department of Defense, specifically the Department of the Navy, for submarine analysis and support. The contract modification will be awarded to Systems Planning and Analysis, Inc. (SPA) to provide subject matter expertise, advisory assistance, program management support, and nuclear-powered submarine platform engineering, technical and construction support and analysis. This support will be provided to foreign military sales (FMS) customers and United States (US) requirements. The contract modification will also include companion US and additional FMS customer requirements. The period of performance will be extended through Fiscal Year 2029. No solicitation documents are available at this time.