Red Sea Dive Boat

Might be able to design a diver lift that works between the bows of a cat - would need to spin the boat around when it came time to pick up divers so as the stern was more facing into the waves and less so the bows as wouldn't get a diver onto the diver lift in two metre waves without broken bones.

I think we will need something with more freeboard around the bows etc than that boat in the pictures as I think that one would have too much water coming over the deck in the Red Sea.

 

Oh dear! That is like open ocean ocean diving in the winter tradewind conditions here.
And any cat with outboards is probably not going to be too keen on backing into the waves to provide a lee for divers to board on a lift between the hulls at the bow, while the waves are merrily breaking over the outboards at the stern.

 

RSD, Thanks for answering all my questions.

Good power to speed numbers from Bajansailor.
Certainly attainable with the right 12m cat.
Weight will be the enemy.

Are you looking at any manufactures in particular?
Especially one that has what suits your needs ( SOR )
already built.
Some diving modifications and you're in business.
Designing and building one could become a disaster.

 

True! Unfortunately the wrecks haven't sunk in nice places like the lee side of a reef - they are just off the edge of the fringing reef that runs parallel to the coast - so right in the wind and waves that run parallel to the coast

 

I'm now reasonably confident that we can get something built by a yard in Egypt, so it is more now getting the design right.

I am quite like the Poleson Marine catamarans - https://www.polesonmarine.co.uk/product-page - a 12 metre x 5.5 metre version of one of those - but with a more angled superstructure like this to reduce the wind it catches - » PURE DIVESeacat Ships https://www.seacatships.com/design/pure-dive/

 

RSD,

Interesting.
Getting the design right on a prototype is a big, big endeavour.
You'd be well advised to hire a professional, no?

What do you know about the dive boat liveaboard that sank in your region in November?
That's enough to make the government rules pucker-up a little.

 

You need cat like bajansailor presented , with some modifcations .
Beam is o.k. but probably you need more clerance to avoid wave slaming . More clerance , higher afterdeck so diver lift design should be smart.
During diving operations its possible to flip down e.g. rigid dense metal net , verticaly between hulls to slow some waves but that's no necessary.
Most important are propeller protectors , that are temporary lowering down and not affected performance during transitions.
If the lenght is limitation , nobody say that you can't flip some huge aluminium build platform , to make diver assist easier or flipping platform next to lift.

 

It was the skyscrapper , one woman ,our client died there.

 

I think so - possibly hire Tommy Poleson seeing as he has the hull already.

I suspect that there might be some changes coming to the rules about liveaboards - especially any new builds.

I'm pretty familiar with the area that it sank. In the "old days" (early to mid-90's), we only used to go down to those areas (what we refer to as the south and deep south) in the summer months from June to early October as that is when the winds are milder due to less temperature differential between northern Africa and the Arabian Peninsula. Now they go down there all year round and it is rough as guts a lot of the time when transiting between reef systems - 4-6 metre seas is the norm in the winter months. November is usually the worst month, they sailed on a Sunday and the weather forecast for that day and the next was particularly ugly - which they would or should have known, and most of the liveaboards that were due to sail that day stayed in port, but this one went out and capsized in the early hours of Monday morning - it didn't actually sink. Another liveaboard that I know pretty well was lost in a major fire in the same area a week or so earlier.

A big part of the problem is the stability of the current liveaboard vessels - there is a bit of an arms race to provide ever more luxury and bigger cabins, and often when they get slipped every 2-3 years another deck is added to allow more and bigger cabins etc. - and stability suffers as a result. It doesn't help that the cross-sections of the hulls of these boats tends to be very very round. Adding to the problems is that a significant percentage of the liveaboard fleet have timber hulls and so vessels popping a plank in rough seas down south in winter is not a blue moon event either.

Why all the divers want to go south in winter has me stuffed, it can be rough enough in the north in November for you to wonder what the hell you are doing there, but the massive number of divers who want to go south in winter shows how little research they do before they book.

November did gift us a new diveable wreck though - the 100 metre long VSG Glory ended up balanced on a reef for a few days then slowly settled by the stern and slid off backwards, the authorities aren't yet allowing diving on the wreck, but reportedly the bow is at 22 metres and the stern is at sixty.

 

MV Sea Story was the one that capsized in big seas, I think seven people haven't been found.

 

Will definitely need more clearance - so as you said diver lift will need to be designed right to do that.

Once things open up again after Christmas I am going to have a chat to Doen Jet to see what price a pair of jets to match say Yanmar 6LY440's would be. Apparently Doen's are about the cheapest of the mainstream jet makers - IF we can afford it then that would be the way to go as jets take away the chance of props damaging divers and coral heads damaging props.

 

Much bigger budget and unfortunately weight . Better engines lifespan .

 

RSD,

Thank you for your thoughtful, thorough reply.
I appreciate your insight.

 

Latest update is that the government is now mandating that there is a minimum of six qualified crew on each liveaboard, but there is some argument going on as to whether the qualification that the government wants them to have is either appropriate or sufficient for the operating area - I am yet to hear what the qualification is called or involves so unfortunately I can't provide any further insight

 

RSD,

Thanks for that.

A "moon pool" well aft of centre, open to the stern,
may serve your purposes.
As may a sea anchor or drogue off the bows on a bridal.
If you put your flybridge further aft, you could incorporate
your lift into it saving some weight and deck space.
Bridge floor windows would allow a second set of eyes
during recovery / launch operations.

In those kind of seas you could easily smack
a diver with the over confidense of no props.
Just the "prop wash" alone ( from jets ) while station
keeping would be hugely disruptive.
Are you ever that close to coral to justify jets?

Just kicking tires here in an effort to brainstorm.

Happy Holidays!