SailNet Community banner
  • SailNet is a forum community dedicated to Sailing enthusiasts. Come join the discussion about sailing, modifications, classifieds, troubleshooting, repairs, reviews, maintenance, and more!

Sugar scoop transom safety in big seas

48762 Views 108 Replies 24 Participants Last post by  jzk
I have a question regarding sugar scoop transom safety in big following seas. It would seem like such a transom might be a liability if a big wave was to crash on it. Same with a transom mounted swim platform, that could possibly be ripped out from it's mounting by a crashing wave.
Any thoughts or experiences?
1 - 7 of 109 Posts
Ya it's almost like the designers at Beneteau didn't think about designing in a transom board to block off the cockpit from a following sea.... Except of course they did, and it's built into every boat, and takes seconds to deploy...

Attachments

See less See more
  • Like
Reactions: 1
John,

1) The transom board is about an inch thick foam coar fiberglass. It may not be as strong as a normal transom, but it's a lot stronger than most.

2) The edges are intentionally left open to allow water drainage. In order to meet the maximum time allowed to drain a flooded cockpit the free area of a drain has to be pretty large, and the smaller the encased volume the less water you have to move. ISO standards require a recess (ie cockpit) to be fully drained in less than 2 minutes.

3) The lower the enclosing bulkhead the less water that needs to be drained, and thus the faster the weight can be gotten rid of.

4) The transom board rides in a slot and the system is designed around a crashing wave coming in from the transom.

5) The hatch boards are manual in nature, the electric is an option. So if the button stops working you just reach down and pull it into place.

6) wide lifting sterns like this have huge amounts of reserve boyancy. Which allows them to lift faster and higher, and thus reduces the likelyhood of shipping a lot of water in the first place.
See less See more
  • Like
Reactions: 2
John,

The low transom is in part required by the large open cockpits. The rules say you have to drain the entire cockpit in no more than 2 minutes (or there is a formula that could require it to be shorter). Given the volume of the cockpits the scuppers would have to be massive to move that much water out in that period of time. By lowering the transom you reduce the volume of water that is potentialy trapped, and thus the amount that needs to be discharged.

The rudder post issue... Meh, it's an engineering problem. I am not convinced Beneteau has solved this, but it's a numbers game and a build quality issue. I have sailed plenty of boats with similar designs that I have no question about. On the other hand the Sense has twin rudders which reduces rudder load by about 40% so the forces involved may actually be lower than on a traditional design.

As for the transom strength issue... its actually pretty easy to measure hull deflection here. A stick on laser level a piece of string and a weight and you can tell how much flex there is in the hull. I have never measured any. This is a pure engineering problem. Like the rudder post I may trust a particular designer or builder more than another, but resolving the problem is really just adding enough strength in the ring frame at the transom to handle the loads. And the loads aren't that high in reality.

And the compression issue is really one that catamarans have had to deal with for a long time. The design challenge of keeping two points (normally the backstay attach,net points) from compressing is one cats have pretty much solved. No more than they require a monolithic plate from hull to hull does a monohull require plate. Arches are stronger, and weigh a lot less.


Finally the hatch board issue... I would have to look at the system to know more. I know it can be accessed completely from the exterior by lifting the access plate. How well it's executed is a different issue. One of the advantages I see however is that unlike most boards that have to be substantially removed and put back (which often aren't) these are more likely to be left partially raised. I also hate fighting the 1/2" acrylic on my boat. They are so heavy my wife finds it hard to deal with them.


Again I will point out that there is a huge difference in how well a design is executed (and I have real issues with my Beneteau in this regard) and if the design itself is sutable. I don't think the Sense is a heavy weather boat for a lot of reasons, but mostly because in my experience Beneteau doesn't build in the type of strength I would want, and their execution of the designs is somewhat lacking. However this is a Beneteau problem not an open transom problem.
See less See more
  • Like
Reactions: 3
Capta - you're kind of all over the place here. So the same conditions that tear away metal work in a cruising boat are okay for a VO70/65 because the crew don't need harnesses, just their pinkies?

Then cruising boats should all be designed for cruising couples over 50 to get pasted in storms?

Sorry, I think this whole debate is a little hysterical.
And let me points it th to big race boats DONT rely on crew muscle to do anything. You can't the loads are too high. They rely on the best deck design money can buy, and installing the right deck gear, in the right place, for the job. Frankly I find sailing a big ocean sled to be easier than sailing most cruising boats. Where cruising boats install all sorts of stuff to make living on board comfortable racers don't. So you don't have Biminie parts in the way, or potted plants in the cockpit, or tables, or, or, or.

The reality is that big ocean racers are probably more comfortable than most cruising boats to be on. Simply because designers know there is a limit to human endurance and delaying hitting that wall is required to good performance.

The most comfortable sea berth i have ever slept on was on an Andrews 70, most comfortable cockpit while sailing Andrews 70, driest cockpit (as sea) Andrews 70. Worst galley Andrews 70, worst salon table Andrews 70 (didn't have one), worst Biminie Andrews 70...
See less See more
  • Like
Reactions: 2
Who knew. I was looking the current line up of Swan's and it looks like due to open transoms all but their smallest are no longer sea worthy. Looks like this icon of off shore sailing should now be limited to 3nm out.
And the new Hylas yachts... Sadly my list of best built boats is getting gutted by the need to stay away from sugar scoops and open transoms...

I am running out of options.

Even Island Packet that hallmark of ancient design has started adding sugar scoops... We are all doomed.

Edit:

Yikes even Hallberg Rassy is now out with their open walk thru transoms... Guys I am running out of options. There may not be a boat made anymore that should be considered reasonable for offshore work anymore.
Yeah - but think about your logic Jon. If you really have reservations about the JSD making your boat vulnerable to pooping - and you really want to kneel at the Altar of Dashew - then you (and him) probably should get a boat just like Seraffyn. After all, it seemed to do pretty well in storms, is very, very simple, super old-school, and didn't even have a sugar-scoop transom. And you seem to want a boat like that.

Nope, can't worship at Dashew's alter. His otherwise incredible FPB 64 isn't safe past 3nm from shore. He designed and installed a sugar scoop, which as we all know makes a boat wholy unsutable for off shore work. Despite being otherwise the best off shore powerboat its size I know.

Attachments

See less See more
1 - 7 of 109 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top