enCaptain AI is an AI-powered, voice-commanded navigation copilot that lets an onboard AI read, query, and reason over next-generation IHO S-100 electronic charts — fully onboard, cloud-free. Solo skippers, reduced bridge teams, and unmanned-vessel operators work where cloud AI cannot follow: mid-ocean, or inside security-isolated naval networks. The S-100 transition, required for new ECDIS installations from 2029, forces costly upgrade decisions. Say "plan the usual route from Mokpo to Gageodo," and a locally hosted LLM queries the chart through 13 purpose-built tools, plans a physics-grounded route, and warns by voice — "obstacle, 333 meters ahead." Delivered as software, it adds seamless S-100 support to compatible legacy bridges. Built on a chart engine proven in HD Hyundai Avikus' HiNAS, Samsung Heavy Industries' SAS, and active naval platforms, enCaptain AI puts a tireless AI second officer on every vessel — from the largest merchant ship to the smallest fishing boat.