Niigata 45m Steel Expedition Yacht With 7,500nm Range: Private Refit, Military-Grade Build! For Sale at $2.7M
A commercial-grade hull transformed for private adventure, with long-range capability, military-grade systems, and a helipad to match.
There are few vessels on the brokerage market that can genuinely tick all the boxes for someone considering a conversion into a private expedition yacht, especially if that person is thinking ahead to serious off-grid cruising or boutique charter operations.
The Niigata 45m, listed for sale with ‘37 South Yachts’, is one such vessel. Originally built in 1995 by the well-regarded Niigata Engineering Co. in Japan, this 45-metre steel-hulled workhorse underwent a comprehensive refit in 2023/24 and once again shows what a private expedition platform, originally deployed as a commercial vessel, can become.
From the outside, she still reads like a serious commercial vessel, with her purposeful lines and upright stance. But step inside, and the story changes. Her interiors, redesigned by Ashley Sutton Design, are anything but austere. This isn’t a bare-bones research ship in disguise; it’s a carefully curated, extremely capable expedition yacht, ready for private ownership with a refined liveaboard aesthetic.
Design and Construction
The Niigata 45m is built to last, with a full steel hull and an aluminium superstructure. She measures 45 metres in length overall, with a beam of 7 metres and a draft of 3.75 metres. Her gross tonnage is 319GT, giving her both the volume and the seakeeping required for extended voyages.
She displaces the water - regardless of sea state - with purpose and authority, and thanks to a series of performance upgrades, her stability at sea has been significantly enhanced by the addition of 18 tonnes of steel to the keel. This ballast modification lowers the vessel's centre of gravity, resulting in reduced roll and improved motion comfort, particularly in beam seas; a vital consideration for long passages and remote anchorages.
Performance and Engineering
At her heart are twin Niigata Power Systems 6M625 engines, delivering 1,103 kW at 750 RPM to a controllable-pitch single screw, paired with articulated Becker-type steering gear. Her top speed sits at 14 knots, but she’s happiest cruising between 10 and 12 knots.
Most importantly, she offers a transoceanic range of 7,500 nautical miles thanks to an enormous fuel capacity of 74,250 litres; that’s just over 19,610 US gallons. With those figures, you’re talking true bluewater off-grid credentials, capable of crossing the Pacific or exploring the most remote archipelagos without constant refuelling.
Supporting her robust propulsion setup is a full suite of heavy-duty navigation and communication gear. This includes a Furuno Navnet TZT19F radar system—a highly capable platform for offshore work and coastal pilotage. There’s also a full spread of electronic equipment, including AIS, sonar, GPS, gyro and magnetic compasses, MF/HF and VHF radios, and Inmarsat-capable satellite communications.
Accommodation and Interior Layout
The main salon on the Niigata 45m is spacious, bright, and practical, framed by large windows that bring in natural light and offer an uninterrupted view of the ocean beyond. The furnishings are comfortable without being ostentatious, offering a home-like atmosphere suited for extended stays aboard. A formal dining area accommodates up to eight guests.
Accommodation is smartly laid out for both private and charter use. There are five cabins in total, with a mix of two doubles and three doubles featuring additional single bunks, accommodating up to 13 guests. All guest cabins are located on the main deck with direct access to the expansive aft deck, underscoring the vessel’s commitment to blending interior comfort with outdoor functionality.
Deck Spaces and Operational Flexibility
The aft deck is classic expedition style: long, open, and versatile. Bean bag loungers and relaxed seating give it a casual, liveaboard feel, while a powerful crane enables tender launch and gear deployment. The swim platform offers water access for divers, swimmers, or tenders.
The sun deck is equally versatile, offering sunbeds, shaded dining, and a semi-enclosed bar area beneath a hard roof, which doubles as a helipad. That heli capability adds another layer of operational independence for owners interested in remote access or guest transfers.
The upper forecastle deck adds further outdoor social space, with twin L-shaped lounges aft and a forward-facing dining area. Forward of that lies the wheelhouse, captain’s quarters, and the operational heart of the vessel.
A Military-Grade Build for Private Adventure
What really sets the Niigata 45m apart is her underlying build quality. Outfitted with military-grade equipment and benefitting from a history of commercial service, she has the bones of a vessel built to work in unforgiving environments. Combine that with the luxury-minded refit and you get an expedition yacht that’s as capable as she is comfortable.
For Sale With 37 South Yachts
If you’re in the market for a vessel that offers serious range, uncompromising stability, and the potential to operate anywhere on the planet, while still being a genuinely inviting place to live, the Niigata 45m demands serious consideration. She is listed for sale for $2.7M with 37 South Yachts (Image Credit).
If you are interested in finding out more about this vessel or any other explorer yacht, please feel free to contact me. For chartering enquiries or questions on other yachts worldwide, regardless of your budget, don’t hesitate to reach out. You can contact me at john@yacht-buoy.com.
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