The orange heavy-lift ship Super Servant 3, lettered Dockwise Yacht Transport, carrying white motor yachts on her deck in the harbour of Toulon, with hills behind
As the yacht carrier Super Servant 3 in Toulon, October 2009, years before her conversion.As Super Servant 3 at La Pallice, France, January 2007

OK

A 1982 semi-submersible transport ship that spent years carrying yachts, rebuilt in Turkey as a private yacht whose aft deck can still sink below the waterline.

Formerly Super Servant 3

146 m
Length
1982
Built as Super Servant 3
2022
Relaunched as a yacht
3,000 m²+
Open deck

In short

OK is a 146-metre private yacht built on the hull of Super Servant 3, a semi-submersible ship that Oshima Shipbuilding in Japan delivered in 1982 and that spent decades carrying yachts as cargo for DYT Yacht Transport (Boat International, YachtBuyer). Karmarine Shipyard in Turkey converted her over three years to an exterior design by Timur Bozca, and she was launched as a yacht in January 2022 (Boat International, SuperyachtNews). She kept the ability to ballast down and submerge her aft deck, so tenders and even a 46-metre sailing yacht can float on board, and the open deck of more than 3,000 square metres has room for some 70 toys, a seaplane and a tennis court (Boat International, SuperyachtNews). Boat International ranks her 11th in its list of the largest yachts in the world, in the March 2025 update of that list, with accommodation for 20 guests (Boat International, Boat International).

Videos

Two tours from YouTube, most viewed first.

This Must be the Strangest 'SuperYacht' Ever!The Yacht Report · 19 Feb 2022 · 321,800 viewsWatch on YouTube
Gigantic Semi-Submersible Ship Transformed into SuperyachtOffshore Spotter | AHTS & Maritime Operations · 9 Feb 2022 · 1,457 viewsWatch on YouTube

Photos

Super Servant 3 in profile at La Pallice, France, her red hull lettered Dockwise Yacht Transport and a yacht on her deck, with a yellow buoy in the foreground
As Super Servant 3 at La Pallice, France, January 2007
Grey US Navy ships sitting on the partly submerged deck of Super Servant 3, with water washing over the deck edge
The US Navy ocean minesweeper USS Impervious and other vessels on her partly submerged deck, Operation Desert Shield, October 1990

The vision was to create a floating island concept that could hold many toys – even a seaplane or another superyacht – without breaking the powerful outlines of the previous version.

Timur Bozca, exterior designer: Boat International, 146m semi-submersible conversion with a tennis court launched at Karmarine Shipyard

Further reading

Independent coverage we found. We link to it rather than rewrite it.

Specifications

Length overall
146 m (479 ft) 139.1 m overall in the VesselFinder AIS database
Beam
32.01 m
Draught
6.26 m
Gross tonnage
11,296
Type
Semi-submersible expedition and support yacht
Original builder
Oshima Shipbuilding, Japan
Built as
Super Servant 3, a semi-submersible transport ship, delivered 1982; she carried heavy cargo before specialising in yachts
Previous career
Carried yachts as cargo for DYT Yacht Transport (Dockwise Yacht Transport); yachts of up to 65 m could float on and off her deck
Military transport
Carried the US Navy ocean minesweeper USS Impervious and other vessels for Operation Desert Shield, 1990
Conversion
Karmarine Shipyard, Turkey; about three years, launched as a yacht January 2022
Exterior design
Timur Bozca (Bozca Design)
Conversion work
New decking (teak at the bow, stern and sides), matte black paint and gold-tinted glazing, a beach club and a crane; accommodation forward stripped out and rebuilt
Construction
Steel hull and superstructure
Engines
2 × Stork-Werkspoor 6TM410 diesels, 3,169 kW (4,250 hp) each
Speed
13 kn max, 11.6 kn cruising
Fuel capacity
53,099 gallons
Guests
20 in 10 cabins
Crew
24
Open deck
More than 3,000 m² 3,300 m² in some reports
Submersible aft deck
Ballasts down so boats can float on board, then pumps out to lift them clear of the water; stern and side loading
Toys and tenders
Room for about 70, including a 46 m sailing yacht, buggies, amphibious vehicles and a seaplane; 40-tonne crane and a car ramp
On board
Pool surrounded by glass, sundeck spa pool, outdoor cinema, botanical garden, four aquariums, tennis court on the aft deck, vertical wind turbine, lift in a glass tower
Flag
Liberia
Owner
Private owner
For sale
Not listed for sale

Where is she now

Live AIS position on:

MarineTrafficVesselFinder

IMO 8025331 · MMSI 636017889

Questions

What is the OK yacht?
OK is a 146-metre private yacht converted from Super Servant 3, a semi-submersible transport ship that Oshima Shipbuilding in Japan built in 1982 (SuperyachtNews) and that spent decades carrying yachts as cargo (Boat International). Karmarine Shipyard in Turkey spent about three years converting her and launched her as a yacht in January 2022 (Boat International, SuperyachtNews).
How big is OK?
She is 146 metres long with a beam of 32.01 metres, a draught of 6.26 metres and a gross tonnage of 11,296 (Boat International, YachtBuyer). Boat International ranks her 11th among the largest yachts in the world (list updated March 2025, Boat International). The VesselFinder AIS database gives a length overall of 139.1 metres (VesselFinder); the published sources do not explain the difference.
What was Super Servant 3?
A semi-submersible heavy-lift ship that first carried heavy cargo and then moved on to yachts (Bateaux.com), spending decades carrying yachts between cruising grounds for DYT Yacht Transport (Boat International); her deck took yachts of up to 65 metres (YachtBuyer). In 1990 she carried the US Navy ocean minesweeper USS Impervious and other vessels for Operation Desert Shield (U.S. Navy photo record).
Can the OK yacht submerge?
Partly. She takes on water ballast to sink her aft deck, so boats can be floated over it; the ballast is then pumped out and the deck and its load rise above the waterline (Boat International). The design allows loading from the stern and from the side, and the submerging deck serves what the designer calls the owner's "island concept" (SuperyachtNews).
What is on board OK?
More than 3,000 square metres of open deck with room for about 70 toys, including a 46-metre sailing yacht and a seaplane, a 40-tonne crane and a car ramp (Boat International, SuperyachtNews). Guests have a pool surrounded by glass, an outdoor cinema, a botanical garden, four aquariums and a tennis court on the aft deck; cabins forward sleep 20 guests (Boat International).
Where is OK now?
Her live position is shown on public AIS trackers: MarineTraffic and VesselFinder. Search by IMO 8025331 or MMSI 636017889; she sails under the Liberian flag, and AIS still lists her as a heavy-load carrier under her current name (VesselFinder).

Compare with

Other converted and support-type yachts in the registry, and one of the same length.

Yas yacht

Yas

141 m motor yacht converted from a Dutch navy frigate, relaunched 2011

Opera yacht

Opera

146.35 m Lürssen motor yacht, delivered 2023

Sources (10)
  1. Boat International, Superyacht Directory: Ok
  2. Boat International, 146m semi-submersible conversion with a tennis court launched at Karmarine Shipyard 31 Jan 2022
  3. Boat International, The top 25 largest yachts in the world 12 Mar 2025
  4. SuperyachtNews, Karmarine Shipyard launches 146m semi-submersible conversion OK 1 Feb 2022
  5. Superyacht Investor, Karamine completes refit of semi-submersible support ship 31 Jan 2022
  6. YachtBuyer, OK
  7. VesselFinder, OK (IMO 8025331)
  8. U.S. Navy photo DN-SC-91-02579 and caption, Operation Desert Shield (Wikimedia Commons) 5 Oct 1990
  9. Wikimedia Commons, Category:IMO 8025331 (Super Servant 3)
  10. Bateaux.com, Superyacht OK, de navire marchand à superyacht semi-submersible (in French) 9 Feb 2022