What makes a 30' boat heavy sea worthy?

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Jul 20, 2005
2,422
Whitby 55 Kemah, Tx
Also do not underestimate the GulF Stream factor as it changes the ballgame. I would rather be in 40 knots in the open ocean than going the wrong way in 20 knots in the Stream.
I totally agree. To me there are three types of dangerous waves 1) those fighting the current 2) rogue (combining waves). 3) storm waves that are steep regardless of current.
 
Nov 22, 2008
3,562
Endeavour 32 Portland, Maine
Jun 6, 2006
6,990
currently boatless wishing Harrington Harbor North, MD
Crew Rest

One of the most critical aspects of weathering the storm is a rest plan. If you know your auto pilot is not going to be able to handle the strengthening storm then let it do what it can while you (your crew rest). Then the crew can hand drive the boat through the worst of the storm.

This also brings up the point, what do you do after dark when you can't see to avoid the breaking waves?
 
Jul 20, 2005
2,422
Whitby 55 Kemah, Tx
One of the most critical aspects of weathering the storm is a rest plan. If you know your auto pilot is not going to be able to handle the strengthening storm then let it do what it can while you (your crew rest). Then the crew can hand drive the boat through the worst of the storm.
I totally agree. If I know a storm is coming and I can't get to protected waters, I'll first make sure I'm away from land, then heave-to to get rest, then run with it when I get worried about being heave-to and I may have to drag a wrap while doing so, then throw out JSD when I either need rest or I'm worried about crashing into a trough. But very very important to get sleep, even if you have to force it with a shot or two of medicine and/or sea sickness medicine.


This also brings up the point, what do you do after dark when you can't see to avoid the breaking waves?
I've asked the same question to my teacher. His response was that you will see the breaking waves because of the floresent fish being disturbed. I asked because it always seems to me the bad weather hits at night and it's cloudy with no moon....aka...total darkness.

Like I said, I'm not sure I think it's the best thing to do because all it takes is one mistake at the helm (I do think the safest thing to do in boat threating situations is the JSD) but if I didn't have a JSD, this would be my techneque for as long as I could handle it. After that I'd go with lying ahull with as many warps or dragging things like hose that would keep the boat at an angle to the waves. I know many sailors spending years doing that and not having difficultly.
 
Sep 25, 2008
2,288
C30 Event Horizon Port Aransas
A copy of Fastnet Force 10 came in the mail today from ebay. Now I will be able to repeat things out of the book and sound like I know what I am talking about.
 
Jun 6, 2006
6,990
currently boatless wishing Harrington Harbor North, MD
Dang it!

He is on to us. Next thing you know he'll be quoting out of Bowditch.

I was told by a very rich person that the first time you use someone else's quote you give him credit, the second time you say "I've read that..." and after that you can use "Like I've always said...."
 
Nov 22, 2008
3,562
Endeavour 32 Portland, Maine
A copy of Fastnet Force 10 came in the mail today from ebay. Now I will be able to repeat things out of the book and sound like I know what I am talking about.
I had several conversations with one of the US researchers into the event in the following couple years. He was plotting various factors out on graphs to look for correlations to indicate which ones made the difference between successfully finishing and being abandoned or capsizing. Eventually, he settled on high rotational moment of intertia (weight distributed out from the centerline) being the primary factor. I think he was wrong about this and indirectly measuring something else. There is a theroretical basis though. If it is harder to start the boat rotating, it will be harder for the wave impact to roll it. Heavier masts and lower keel weight help. The former reduces stability and the latter puts the keel deeper into water that is moving slower relative to the wave crest so I don't think that finding translates into a prescription for a safe boat.

A more interesting correlation that he told me about, although I never saw the data or recall whether it made it into his paper, is speed. If you graph the speeds of the vessels up until either finish or abandonment aand convert to speed length ratio, you find that, the faster they went, the greater their chance of finishing.

These were racing boats with large crews used to steering under challenging conditions with a lot of sail up so I don't think it applies to cruising. It may also be a measure of something else like crew ability or getting ahead of the worst conditions.

I believe the winner (Ted Turner) said on coming ashore something like, "Storm? What, there was a storm?".
 
Jan 1, 2009
371
Atlantic 42 Honolulu
Eventually, he settled on high rotational moment of intertia (weight distributed out from the centerline) being the primary factor. I think he was wrong about this and indirectly measuring something else. There is a theroretical basis though. If it is harder to start the boat rotating, it will be harder for the wave impact to roll it.
Based as I recall (a long way from my library) at least in part on the very high rate of repeat roll over events for boats that lost their rigs. Conclusion: avoid dropping your rig in snotty wx if you can... (for this we needed a study?:))

Shuttleworth studying cats and tris in breaking sea conditions in a wave tank also concluded that a high mass moment of inertia was the main factor in avoiding capsize. His theory was that in large breaking seas the wave passed quite quickly under a boat and thus did not have time to capsize boats with high moments. He claimed that this made cats inherently more resistant to wave capsize than tris of otherwise similar length beam and displacement.

FWIW, I stack sails and stow some of my heavier gear outboard as there isn't much if any day to day disadvantage to doing that on a cat. In a monohull there is likely to be more of a trade off as weight stowed outboard tends to be stowed higher in the boat. Also, I try to keep the ends light as slow pitch response is wetter and slower on my boat (and most others).

--Tom.
 
Jul 20, 2005
2,422
Whitby 55 Kemah, Tx
A more interesting correlation that he told me about, although I never saw the data or recall whether it made it into his paper, is speed. If you graph the speeds of the vessels up until either finish or abandonment aand convert to speed length ratio, you find that, the faster they went, the greater their chance of finishing.

These were racing boats with large crews used to steering under challenging conditions with a lot of sail up so I don't think it applies to cruising. It may also be a measure of something else like crew ability or getting ahead of the worst conditions.

I believe the winner (Ted Turner) said on coming ashore something like, "Storm? What, there was a storm?".
Ted is a nut :)

That's exactly what I was told as the safest solution....keeping as much sail up as you can to give you the most possible speed so you can dodge the breaking waves. If you aren't dodging the breaks such as having the autopilot on, I feel you are putting the boat in a great chance of crashing into the trough.

This is not for the average helmsman though as broaching is a real danger and having a breaking wave catch you causing you to slide down the front face of the wave and crash into the trough at 40+ mph is also possible.

The reason you want to use the sails instead of the engine is because the engine's filters have a great chance of clogging. You may have just cleaned your tank a month ago but when you filled it up, you may have taken on bad fuel which has happened to me a few times. Another reason is that the sails stabilize the boat which reduces chance of injury and damage to boat.

I really don't know if I can dodge breaking waves in a hugh storm. I've often thought what type of sail plan would I have. Would I have just the working jib out or part of it? Would I have just half the main out? Would I have a little of both? One thing is for sure, this is when I will love my roller furlings :) If you don't have them, you have to make your sail changes before it gets rough.

I see dangers in all solutions. If I have the main out, I had to worry about accidental gybe and bringing down the mast. If I have the jib out, I will have more rolling as it's less stable. If I am by myself, I can't gybe because I have nobody to handle the sheets and/or boom. If I can't gybe, then that may cripple my changes of dodging a breaking wave.

One thing I do know, because I've been studying other peoples experiences and applying my own experience, I have a list of things I can try and I'm sure to find one that will work. I know my list of things to try is much bigger then it was 3 years ago (feathering, heave-to, lying ahull with warps, running and dodging, last is JSD)

I have comfort in knowing that no boat has ever had any damage while on JSD in 15 years of it being around and I have one incase I can't dodge the waves or feel it's unsafe.
 
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Sep 24, 1999
1,511
Hunter H46LE Sausalito
a breaking wave isn't quite as scary...

Ted is a nut :)

That's exactly what I was told as the safest solution....keeping as much sail up as you can to give you the most possible speed so you can dodge the breaking waves. If you aren't dodging the breaks such as having the autopilot on, I feel you are putting the boat in a great chance of crashing into the trough.
.
...if you're moving along as fast as it is. But you don't ever want to be moving faster than the breaks, at least not in non-racing situations.
 
Jul 20, 2005
2,422
Whitby 55 Kemah, Tx
...if you're moving along as fast as it is. But you don't ever want to be moving faster than the breaks, at least not in non-racing situations.
As fast as the breaking waves? Umm...we are talking about a displacement monohull here, which a 30' tops out about 7 knots. Waves go a lot faster then that and the breaks are just as fast.

I think this will explain it a lot better then I can...
http://www.jordanseriesdrogue.com/D_9.htm
 
Sep 25, 2008
2,288
C30 Event Horizon Port Aransas
I still don't get how the c30's hull makes a rougher ride in heavy seas because of the flat bottom. Why would they build a boat that would be uncomfortable? In what type of seas is the C30 made for? What I mean by that is; is the c30 better in a choppy sea than an ocean going vessel? There has to be some advantage to the flat bottom, otherwise they would just make it deeper.
This may be something I have to experience to understand.
 
Sep 25, 2008
2,288
C30 Event Horizon Port Aransas
Hey I was reading back through this post and when I said "I would soon be repeating things out of the book and sound like I knew what I was talking about" I wasn't refering to anyone on here, nor was intending to insult or attemp to insult anyone. I just wanted to make that clear. I'm jsut making fun of my inexperience, nothing more.
When I first found this forum, some guy on here was emailing with me or PMing with me and we were talking about what makes a boat ocean worthy. He sent me a picture of his boat with his dog on deck. Then he mentioned something about how the admiral doesn't like the heel of the boat or something like that. I emailed him back and asked if the dog was "the admiral". Needless to say he didn't email me back again. I really didn't get the admiral is your wife thing for quite some time. When I realized what I had done I couldn't find the guys message. So if you read this, please know I wasn't insulting your wife, I just thought the dogs name was amiral because he was in the picture.
 
Nov 22, 2008
3,562
Endeavour 32 Portland, Maine
I still don't get how the c30's hull makes a rougher ride in heavy seas because of the flat bottom.
Boom, splash, boom, boom, boom, splash, BOOM, splash, splash, boom, SPLASH, boom, BOOM, splash, ......

Why would they build a boat that would be uncomfortable?
Faster. More room for the length. Less heel. Comfortable enough in the small, fair weather seas 90% of sailing is done in, that number including the fact that 75% of typical boat usage is at the dock.
 
Jan 27, 2008
3,086
ODay 35 Beaufort, NC
Cruising boats at sea

Scott,
Check out the Marion to Bermuda race. This is a race for cruising sailors run every two years from Marion Mass. to Bermuda. They run the Newport to Bermuda to other years. The Marion race is for typical cruising boats. I don't consider the O'Day 35 a bluewater boat but the O'Day 34 won the race back in like 1990. By anyones standards these are coastal cruising boats just like yours. I've spent five days or so at sea in my 35 not in severe conditions but in 35 knot winds. I did have a JSD with me. SOmeone mentioned night time sailing. On a clear night with stars and 12 knots of wind and maybe a moon, there is nothing better, I love sailing in those conditions. On a stormy night there is nothing much worse. Total darkness, you can't see the waves coming at you, all you can do is stare at the compass and stay on course. Picture staring at a lightbulb for hours, it really hurts your eyes. One of the great things about sailing is the nedless variety and the challenge to the self to deal with ever changing conditions. Every so often they get too challenging, luckily I haven't seen that yet, but have had my share of excitement. I think reading about the Marion race will convince you your boat is capable of the trip you plan to undertake, if you can tag along with another boat even better for piece of mind. As for the wife, why not have her meet you there, a couple hundred dollar plane ticket could eliminate a lot of your anxiety. Get a crew to go with you, someone I'm sure would want to sail to the bahamas.
 
Jan 27, 2008
3,086
ODay 35 Beaufort, NC
Yukon Jack

Here's the story of how an O'Day 34 won the Marion to Bermuda race. This is about a 650 to 700 mile race offshore. So as you can see lots of production cruising boats go offshore.

Fluke winds delayed the start of the 1989 Race several times, forcing a colossal fleet of 163 vessels to mill around and avoid one another at the starting line far longer than anyone would have liked. Good seamanship prevailed, however, and the fleet eventually got away cleanly. Warren Brown's WAR BABY smashed the previous year's record time, arriving in Bermuda after only 72 and ½ hours at sea. YUKON JACK, a 34-foot Class F sloop sailed by Beverly Yacht Club member John Elliot, won corrected time honors, edging out Commodore Jim Hayes of the Blue Water Sailing Club in the 40-foot Class E sloop SHAMBLES.
 
Oct 22, 2008
3,502
- Telstar 28 Buzzards Bay
Of course, having proper storm gear, like a Jordan Series Drogue, can make things much safer if you encounter a bad storm.
 
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