Flotation Questions - Real Answers from Engineers Out There?

[whitejw1967]

I know added flotation/buoyancy has been discussed 'ad nauseum' on the site. However, there are very few 'real' answers. I'm thus throwing this out to the experienced folk, especially those with backgrounds in such things:

1) Can a DSII be righted if capsized? If so, can it be done solo?
2) Will the DSII turtle when capsized, and if so, under what conditions and after how long over? Can it be righted without help from other boats?
3) Could filling the mast with foam keep the boat from turning turtle?
4) Unless there is significant water in the bilge (on a DSII) why would adding flotation to that area affect buoyancy or center of flotation in a capsize? Seems to me that adding foam (noodles) where there is normally just an air pocket wouldn't make any difference EXCEPT if the bilge area takes on water? Is this incorrect?

So, in short, what are the negatives of adding flotation, especially to a 37 year old boat?

Happy sailing.

JWhite

[jdubes]

I'm not being snippy here, but asking whether or not a DS can turtle, is like asking if an air bag will always protect you in a crash. If you get hit hard enough the air bag probably won't help as much. If you get slammed down in high winds quickly enough, and you don't react and your deep enough that would allow the boat to completely turtle, then you can turtle a DS.

I would not have the mast filled with additional flotation if that wasn't the way it was designed. If anything having additional mass farther up the mast would introduce more risk.

Most sailboat and boats that aren't self righting would be a real challenge to right singled handed if they turtled and the mast didn't break off.

Bottom line if the conditions were right, all the conditions, and you don't react accordingly you could turtle a DS. I go out in all types of conditions, and turtling a DS is the least of my worries. I'm more worried that i'm going to break a mast stay while i'm sitting on the rail with friends in 20 knot winds.

The only real flotation i would add to the situation would be to keep my ego floating. Because i just turtled a daysailer.

[Moose]

I believe it did originally come with foam filled spars. Adding anything to the bilge area (other than a gas less dense than air, like helium) will only weight your boat down provided its reasonably air tight. there is really no advantage unless the hull is compromised.

I'm more of an engineering student than an engineer but soon enough!

[Roger]

My DS II's mast was foam filled. I always thought that was how it came from the manufacturer, but perhaps I am wrong.

As for floatation, I have had a foot of water in the cockpit and bilge and it still floated. The best way to prevent a capsize is to sail with the mainsheet in you hand ready to uncleat in a huge gust.

These boats are stable, but can capsize and can turn turtle. Self rescueing solo is a real chore. It can be accomplished with two people, but still a chore if it occurs in really wild conditions. Best to avoid capsize.

[Toso]

Correct me if I'm wrong but I believe that foam filled spars was an option for certain years, My understanding is that the flotation aspect of foam is minimal in the mast but the foam keeps the mast from filling with water which is heavy. This can really help in recovery.

[talbot]

I would look at the stories of actual capsizes that are sprinkled through the forum. What I have derived:
1. Capsizes are usually associated with a jib sheet that isn't released in time. This corresponds to my experience. The main alone will almost always weather up, but the jib can pull the bow downwind.
2. If the cabin fills with water, you have no chance of righting the boat.
3. Anything that helps slow the flood of water into the cabin helps. But you need to get on the board quickly.
4. A capsized DS II won't sink, but it's so wide that on its side, the mast is angled down, making it prone to turtle.

My responses:
1. Last year I bought Toys R Us completely out of those long swimming-pool foam tubes, which are stuffed between the hulls through the inspection ports I installed when adding oarlocks (another thread on this forum).
2. I am crafting what I hope will be a waterproof hatch, which is now standard on new Cape Cod Daysailors. It's sitting clamped on my workbench now. Hatch construction is another thread on this forum.
3. I installed waterproof seals on the mast tabernacle, sealed all the fittings on the mast with silicone, installed brass liners and drain plugs on the cuddy drain holes, and I replaced the plastic CB control fairlead through the bulkhead with a smaller diameter that just accomodates a 1/4" Sta-Set X uphaul.
4. I intend to sail so that I never, ever, have to try any of this stuff out to see if it works.

[persephone]

To me it isn't a question of flotation so much as it is about keeping water from filling the boat. If you do nothing, once capsized the boat will eventually fill up, bilge and all. Then you will have to remove all that water. What is the volume of the interior of a DS2?? If you fill as many of the voids as you can then water can't displace the fill material and you reduce the volume of water to be removed. Less water equals faster recovery time.

Honestly I can't think of any negatives to adding flotation to any boat built before the current standard. If capsized, our boats would be able to keep themselves from sinking for a limited amount of time. Add 600+ pounds of positive buoyancy and the hull (plus rig) will never sink. Add more and it will support crew indefinitely as well.

[Michael Mellor]

Yes,

My wife and I did it two days ago. My wife is learning how to sail and we have two other sailboats she is use to sailing, that are self righting, and point up when pushed too far. I wasn't paying attention and we got caught in a big gust. My wife panicked, instead of letting go she headed up and in a few seconds the mast and sails were flat on the water. In the time it took to bail out and get on the back side of the hull, our boat was completely up side down. I was surprised at the speed of the capsize. We live in Oregon and the water this time of year is around 50 deg. We always have PDF's on board but I only wear one when I single hand. Big mistake. There were only a few other boats out and we were really lucky we got help. We couldn't have made it to shore if we had to swim for it.

Lessons learned,

A DS11 can go turtle quickly if your not paying attention. I was surprised how much water the boat will take on. The inner hull was full. We were lucky and it was a good lesson. It's not something I would like to do again, and I've been sailing for a long time and was caught of guard.
I hope this helps someone else.

Michael

[Alan]

Wow, that's scary.

When you refer to the inner hull, are you talking about the cuddy? In that case, the time I've invested in making a watertight cuddy door may well have been worth it. I hope never to find out, but turning the cuddy into a giant air tank seems like a good idea.

[Melbourne55]

I have been told a milk bottle attached to the mast can prevent turtling. Not pretty but you do see them out there. My brother who has totally rebuilt a sailboat has a friend in Fort Pierce who has worked with fibergless boats for a long time. He suggests for floatation,since he has seen noodles waterlog, that you use soft drink bottles sealed with silicone. Cheap, light and almost indestructible. Easy to remove too.

[jdubes]

I was doing my normal search on Ebay for DS parts and accessories, and i came across this. Check out this anti-turtling device on this hunter.

http://cgi.ebay.com/ebaymotors/Hunter-170-Sailboat-Daysailer-_W0QQcmdZViewItemQQhashZitem2c55691acaQQitemZ190411512522QQptZSailboats#ht_708wt_1167

[Alan]

Looks like a Hobie mast float. Sailsport Marine has them for $114.25.

[jdubes]

I can see the potential for use, but i can't help but wonder what it would look like actually attached to the mast.

[Alan]

I saw one on a Hobie at a local reservoir. Visually, it's sort of jarring. But then, so is a turtled boat.

Somebody on a thread somewhere (not sure if it was here) said he told people his was a radar reflector so they wouldn't make fun of him.