First look inside 50m converted naval ship JeMaSa (ex Plan B)

8 images

Credit: Jeff Brown

First look inside 50m converted naval ship JeMaSa (ex Plan B)

6 October 2025 • Written by Dea Jusufi

Brokerage firm Y.CO has offered a first look inside the 52-metre HMA Naval Dockyard explorer yacht JeMaSa  (ex Plan B), which was relaunched earlier this year following a year-long, multi-million-dollar refit program in Australia. 

Works, which were undertaken at Gold Coast City Marina & Shipyard (GCCM), encompassed interior outfitting, full exterior refinishing and engineering works. The "finishing touch" was the installation of a new swim platform, which increased the yacht's LOA from 49.9 to 52 metres.

JeMaSa will operate predominantly in the South Pacific as a private and a "one-of-a-kind" charter yacht. "From diving, game fishing, water toys exhilaration and access to the world's most beautiful destinations, JeMaSa offers freedom, exploration and fun," added the broker.

JeMaSa was built as an Australian naval ship in 1973 before being transformed into a fully-fledged explorer. The former survey boat has a steel hull and a steel superstructure, a beam of 10 metres, a draught of 3.2 metres and a volume of 746GT. For the refit, Misha Merzliakov was the chosen interior and exterior designer while Periscope's Shaun Phelps was responsible for naval architecture.

"The project involved stripping the vessel back to bare metal, followed by a comprehensive redesign to ensure compliance with Class and Flag regulations," explained refit manager Juan Koegelenberg. "[We've] converted JeMaSa to a five-star global cruising motor yacht for the charter market."

As part of her refit, the yacht received new upholstery, wall and ceiling panels, as well as new custom beds and furniture. All guest areas – including the six en suite cabins – benefitted from new marble-top bathrooms. JeMaSa's De Villiers-designed exterior has also been tweaked, with her military-style profile tempered by a bright white superstructure and light grey hull.

Some initial sketches of the refit work

On deck, an enclosed "glass house" with sliding doors at bridge deck level was created by the glazing experts at The Boat Works. The windows were also replaced with larger format glazing (courtesy of Integ Marine Windows) for more light and panoramic views.

Andrew Chapman, GCCM’s COO added: "We are very proud to work, once again, with Juan. With his specialised companies – X-Plorer Yachts, Liquid Yacht and Marine Scaffolding – Juan has tremendous experience in the transformation of huge vessels here at GCCM."

JeMaSa's four decks now offer al fresco dining and further spaces to unwind, while the newly rebuilt interiors feature a "modern, light aesthetic that utilises organic materials". The interiors also include seven adaptable cabins, including two that can be converted between twin and king configurations, alongside a cinema room, sauna and games room.

He added: "Projects like this bring many if not all our in-house talented master craftsmen together and the results are spectacular. This is why owners choose to bring their million-dollar vessels to GCCM."

The exploration yacht, with Pacific Ocean-crossing capabilities, is powered by twin Caterpillar diesel engines, delivering a top speed of 12 knots and a maximum range of 7,000 nautical miles.

The yacht was sold in December 2023 at a last known asking price of $14,900,000.

Read More/50m converted naval ship Plan B sold

More about this yacht

HMA Naval Dockyard   49.99 m •  1973

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