To capsize or not!
My wife and I own a 24' Neptune with a shoal keel. It is our first sailboat and we have sailed around the San Juan Islands for the past 3 years. We mainly sail in the summer so we don't encounter too much wind. When, on occaision, I do run into 15 knots or so of wind, I find the boat heels over fairly easily to between 20 and 30 degrees, at which point I spill the sails for fear of capsizing. I had considered a reef but the gusts that create this level of heeling are usually short lived.
I realized I really have no knowledge of this boat's (or any boat's) ability to capsize.
Can this happen easily in a 15-20 knot wind or would it be harder to achieve than I think?
What does it really take to capsize a boat and how does the boat design affect this?
Here are some stats on my boat that might help.
LOA = 24'
LWL = 21'
Dispacement = 3200
Balast = 1200
Sail Area = 250sf
Draft = 2'
Beam = 2'
Any thoughts and considerations would be much appreciated.
Hey, welcome to Sailnet! I had a Hunter 23 before my Oday 30. So I have some experience in your type boat. I would say this; Have you ever tried to "capsize" your boat? Chances are it would be very difficult and the tiller would break or rip out of your hands because she will want to "round up" (point into the wind) first. Not recommended! The specs seem to indicate she's self righting also. Reefing. too late when the wind pipes up. On open water less is more" when the winds increase. Spilling the sails is good yet at some point you may be dipping the boom. you NEED to know your weather. Reefs are easy to let out and difficult to make in a blow.
Suggestions; Seal up the ports and cabin. Go and try to capsize your boat! See how much she will take to prove to you she's more able then you in a blow. (have a friend with another boat on standby)
Pretty boat! this may not be your actual boat.
[IMG]Neptune 24 CB drawing on sailboatdata.com[/IMG]
You can calculate righting moment of the bait. Google to find method.
I am unfamiliar with the boat, but very few keelboats have positive floatation, they'll sink pretty fast once they fill with water.
Are you sailing with a big 150% foresail ? You might want to try to use a 95% jib in windy conditions.
Also, study sail trimming techniques to depower the sails ( espeicllynthe main )
I had a 26' Chrysler that was pretty solid in my opinion. A storm was rolling in when we were headed to the slip one time, and the wind changed direction by 30 degrees and upped it's speed a LOT (not sure how much, but it's still the biggest gust I've seen on Lake Lanier).
When the direction and wind speed changed we were sailing pretty close to the wind on a starboard tack, with a 130% genoa and the main up.
Then BAM it hit us directly from the side and the top of my mast was _maybe_ 12' above the water, and just as quick, we were up again, but it was a very gusty wind and I let both sails go, brought them down and we motored in.
That keel will do a LOT to keep your boat from going all the way over.
I'm pretty sure I would not test it too hard though, as Denise suggested. She may be right, but I'd check the sea ratings of the boat and search for a forum dedicated to your make/model and learn from their experiences.
Have fun though, sounds like a fun boat. You may want to see if you can borrow/rent a smaller boat sometime. You can learn a lot about wind and sail trimming on them pretty quickly.
Yes, sorry I don't mean to try and sink your boat. just try and see what it takes to really get her heeled over allot.
I'm going to take a wild guess here and say that with 1200 pounds of keel ballast underneath (by subtraction) a 2000 pound hull, you're going to have an extremely difficult time capsizing her (meaning she goes way over, mast in the water, and won't recover). She may heel way over if you are 'making' her (meaning too much sail not eased enough, or getting caught aback, or some kind of jibe-broach deal downwind, or the like) but the boat *will* recover if you will just let her (and you had your hatches closed to avoid downflooding).
What sometimes happens in the debacles mentioned above, is the crew on a lightweight boat doesn't/can't hang onto the high side, and fall to lee (or in an accidental jibe they're now suddenly on the low side), the worst possible place for them, and for the boat's stability. Crew weight placement is a big factor in boats less than, say, 7000 pounds or so.
Welcome to Sailnet, you can learn alot here. Go to this calculator: Sail Calculator Pro v3.53 - 2500+ boats and you will find that your capsize factor is 2.17. 2.0 and lower are considered good.
It is pretty hard for the wind alone to capsize your keel boat, it may knock you down, ie put the mast head in the water, but it would take a combination of wind and wave to turn you completely over.
"What does it really take to capsize a boat "
One good squall, that's all.
Consider the J/24 which was considered "uncapsizeable". Squall line came through the NY/NJ area in the 90's while a fleet was out racing, put one over on her ear, water came in through the cockpit lockers and flooded the boat out below. Capsized. And that's not the only one.
Push hard enough, and anything goes over. Most stuff also rolls back upright, if you have prepared the boat. That can mean sealing lazarettes off, or at least securing their covers, and putting in the companionway boards in rough wx.
The capsize ratios give you a way to compare you boat to others, and to see how much push it will take to start it over. But as long as you don't plant the mast in the mud, you can take reasonable steps to ensure it will keep rolling right over and come back up again.
Some boats have high "initial stability" meaning, you step aboard and they don't rock. Others are tender and have more "form stability" meaning, they'lleasily roll and put a shoulder to the water, and then dig in and remain stable at that heel angle. Most are one or the other these days, very few are actually tender AND tippy AND inclined to keep rolling on over.
20-30 degrees of heel may feel like much but your keel ballast have just started working at that point. What you have, as pointed out above, is probably an initial stability issue which will happen if your boat is not very beamy or has a round underbody. You will find that capsizing a keelboat is harder than one might think.
Even my sailing dinghy without a keel surprised me. You step on it and it feels like it will roll over on slightest imbalance. Feels much more stable when heeled under sail.
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