Two tunnel and a swing down in the front. The z-drives and a tunnel in the stern if memory serves me. I could be wrong about the skeg stern thruster though.
If you are talking about the ones ECO is building, the that was suppose to be built in the states has been put on hold, which was a request by the client…so I have heard. Haha
[QUOTE=z-drive;159501]Sponsons aren’t always an afterthought; that is all. They aren’t always that pronounced, or low on the hull, but the same idea regardless.[/QUOTE]
Might not be an afterthought, but naval architects still consider it “bad design”. STX vessels are pretty straight forward, very straight edges - when it comes to hull hydrodynamics, not the most efficient but makes them easier to build. The “stepped design” of this vessel’s sponsons isn’t good with regards to resistance and operation at low drafts (slamming of waves against the lower edge). I worked on the design of the Bram Atlas, and the team added sponsons which extended above the deck as an enclosed cargo rail (to add buoyancy) as an afterthought when the vessel couldn’t pass towing stability guidelines without them. However, the Bram Atlas sponsons were smoothened at the edges and made to “fit in” with the hull geometry, so it doesn’t stand out like this one on the HOS Warland.