Spot the (rather unusual) boat...

[MapisM]

Well, unusual for a pleasure boat marina, anyway!

 

[guyd]

Ice breaker?

 

[vas]

Ice breaker?

that's what I thought, but (assuming P is at his home marina and this is the bow of his boat) an icebreaker in the Med??? Doing exactly what?

cheers

V.

 

[MapisM]

assuming P is at his home marina and this is the bow of his boat

Yes I am, but no, it isn't - the Sardinian flag is on the bow of a neighbor's Canados, in fact.

And the vessel ain't an icebreaker.
Far from it, in fact: I was extremely surprised, after googling for her, that she's built in composite material...!
Though in hindsight, the smooth flare on the hull gave away the fact that she's not a steel boat.
A very specific purpose vessel she is, anyway. All 300+ tons of it.
I won't spill the beans yet, just in case anyone else would wish to try winning the virtual cigar.
But of course this is just a detail of a much more general pic, so stay tuned...

 

[RobWales]

Minesweeper?

 

[Erik C]

Sonar?

 

[vas]

the non-paid version of Marinetraffic wont go back to port arrivals/departures more than a day, so wont help either...

just saying

V.

 

[MapisM]

Aha, I didn't consider that possibility!
Though she actually came already one week ago, and only stayed for a couple of days.
I posted the pic yesterday just because I didn't download it from the camera before...

Anyway, after the minesweeper D!), I suppose it's unlikely to guess that she's a French DRASSM (Département des recherches archéologiques subaquatiques et sous-marines) vessel... Quite impressive, in flesh!

 

[vas]

interesting,

why does it have to be of a composite structure though? Anything to do with radar/sonar or whatnot they use for the examination of the seabed?
Wonder to what extend a big mass of metal (the engine) is going to affect the operations.

And why this odd bow design? Of course could be filled with lots of sonar equipment, but I'd expect them to be located close to the COG for less movement and potential errors on bumpy seas...

cheers

V

 

[MapisM]

Sorry V, I thought to approach some crew member to understand more about the vessel and what they were doing, but I've been a bit busy while they were here and never came across any of them while walking along the dock.
So, all I know is what you can find by googling "André Malraux" - and excluding the novelist, to whom I suppose the vessel name is dedicated!

 

[Bajansailor]

That bow shape looks rather like the 'beak' wave piercer hull form initially developed by Pantocarene for pilot boats -
http://b-m-e.pagesperso-orange.fr/cariboost2/crbst_4.html

Here is an interesting article about this hull form -
http://www.pilotmag.co.uk/2008/01/08/new-pilot-cutter-design/

And there is a very long thread on the Boat Design Forum about wave piercing bows in general -
http://www.boatdesign.net/forums/bo...rs-marketing-myth-design-ingenuity-30296.html

In the past everybody thought that you needed to have a lot of flare on the bow in order to have good sea keeping - flare keeps the spray down, but increases the risk of slamming.
These beaks do help to reduce slamming and vertical motions - another approach is to go the opposite way, like what Ulstein did with their 'X' bow.
Here is the Polarcus Adira - she is a seismic research vessel built by Ulstein with the X bow.
http://www.marinetraffic.com/en/ais...:9610183/mmsi:311052900/vessel:POLARCUS ADIRA
I visited her recently in Trinidad, before she set sail for Brazil for a 6 month seismic contract there. The crew told me that she has a far more comfortable motion at sea than more 'conventional' hull shapes - the crew mess is right up in the bow, and even when powering into a 3m. head sea at cruising speed there is negligible motion felt in the mess room.

 

[Bajansailor]

This wave piercing bow almost looks like an afterthought, but from the photos of the vessel on Marinetraffic she appears to have been built with it.

http://www.marinetraffic.com/en/ais...si:228353900/imo:9666302/vessel:ANDRE MALRAUX

It should usefully reduce the wavemaking resistance at displacement speeds, as it effectively makes the half angle of entry at the waterline much smaller. One could then logically think the next step would be a vertical bow at the end of the beak (a bit like Steve Jobs' Feadship), followed by the reverse 'X-bow', but traditional appearance is often an important factor to consider in the design.

 

[prv]

And why this odd bow design?

I'm sure I've seen it quite commonly on French trawlers around Cherbourg and St Vaast. I assume there's a good hydrodynamic reason.

See eg:

Even the grocklemobile at St Vaast has it:

Pete

 

[MapisM]

traditional appearance is often an important factor to consider in the design.

True for most pleasure vessels surely, but I don't think aesthetic was a major concern for whoever designed this vessel...