The ASD Tug is a versatile, high‑performance harbor and coastal tug designed around the azimuth stern drive propulsion concept. Its compact size, powerful bollard pull, and exceptional maneuverability make it suitable for ship handling in confined ports, escort duties, coastal towing, and general support operations. The hull form is optimized for both free‑running speed and high thrust at low speeds, providing a balance between efficiency and control. High bow flare and freeboard improve seakeeping and dryness on deck, while fendering arrangements are configured for safe contact with a wide variety of vessel hull shapes.At the heart of the tug’s performance are two azimuthing thrusters mounted aft, driven by medium‑ or high‑speed diesel engines through resiliently mounted gearboxes. This propulsion layout enables full 360‑degree thrust, allowing the vessel to move sideways, turn within its own length, and maintain precise position alongside large ships or structures. Typical bollard pull ranges from 40 to over 80 tonnes, depending on engine selection and displacement, with free‑running speeds commonly in the 11–13 knot range. The propulsion system can be adapted to different fuel and emission requirements, including the integration of hybrid or low‑emission solutions.The deck layout is arranged for safe and efficient towing and ship‑handling operations. A heavy‑duty towing winch is generally positioned forward for escort and berthing work, with an optional aft winch for towing astern or coastal towage. The winches can be specified with single or double drums, render‑recovery controls, and tension monitoring to optimize line handling and safety. A robust towing staple or escort towing point is integrated into the structure, designed to withstand high dynamic forces. Generous working deck areas, non‑slip surfaces, and strategically placed bollards and fairleads support a variety of operational configurations.Safety and crew comfort are central design considerations. The wheelhouse provides all‑round visibility, with particularly clear sightlines to the bow, working decks, and thrusters’ wash. Ergonomically arranged consoles and controls enable one‑person operation of propulsion, winches, and navigation systems under normal conditions. Accommodation spaces typically include cabins for a small crew, a mess and galley, sanitary facilities, and storage, all arranged to minimize noise and vibration from the engine room. Fire safety and damage stability standards follow relevant international rules, with options for fire‑fighting systems, including external FiFi capabilities where required.The ASD Tug concept is highly flexible and can be tailored to individual operator needs. Variants can be configured for specific roles such as escort towing with enhanced stability and steering forces, terminal support for LNG or oil facilities with advanced fire‑fighting and fendering, or shallow‑draft operations in rivers and estuaries. The design supports compliance with major classification societies and international regulations, including provisions for future environmental requirements. This combination of maneuverability, power, safety, and adaptability has made the ASD Tug a preferred workhorse for modern port and offshore support fleets worldwide.