Luna

Luna is a historic tugboat normally berthed in Boston Harbor, Massachusetts. Luna was designed in 1930 by John G. Alden and built by M.M. Davis and Bethlehem Steel. She is listed on the National Register of Historic Places and is a U.S. National Historic Landmark. In 1985, the Luna was designated as a Boston Landmark by the Boston Landmarks Commission. Luna is the last surviving full-sized wooden ship-docking tug on the US Gulf and Atlantic coasts and was the world's first diesel-electric tugboat built for commercial service. These two distinctions have led to designation of Luna as a US National Historic Landmark. Today Luna is preserved in Boston Harbor, where her rehabilitation process has been underway since the tug was rescued from being broken up in 1995. Luna is the responsibility of the Luna Preservation Society and its progress is recorded in their website. Due to her wartime service with a civilian crew, Luna is also a member of the Naval Historic Vessel Association. Vessel design Luna was designed by John G. Alden (1884–1962), one of America's greatest and most prolific yacht designers, but was heavily influenced by the preferences of the tug's owner, the Mystic Steamship Company, and its subsidiary Boston Tow Boat Company. As a result, Lunas aesthetics embody the classical sweeping profile of the American harbor tug. The tugboat also had a very innovative propulsion plant: two diesel engines, each turning a generator and exciter to create DC current, which was then shunted (via prototypical switchboards) to a single DC motor (weighing 20 tons) attached to a single propeller shaft. The project was a showpiece for Thomas Edison's General Electric Corporation, which seized the challenge to design, build and deliver the components, in conjunction with their control subcontractors. Six years after Lunas delivery, GE reported that there were 33 diesel-electric tugs in service, 21 of which were GE installations. Lunas wooden hull and deckhouses were built by the M.M. Davis Shipbuilding Company in Solomons, Maryland. The empty hull was towed from the Chesapeake to East Boston for outfitting at the Bethlehem Steel Shipyard in East Boston.