Desirable and Undesirable Characteristics of Offshore Yachts

CapDave

Anarchist
615
710
Bermuda
yes, exactly.

A small complication is that the gribs particularly (but also the 'human' met products, especially offshore) systematically underrepresent these 'small hot zones'. So you as the user need to have enough knowledge/experience to know when they will likely be there based on the system that is shown.  This has gotten better over time as grib cell sizes have decreased but is still an area where human judgement and art is quite valuable.
Absolutely true, and too many people have become over-reliant on intra-cell interpolations by fancy software with pretty pictures. Looking at CAPE charts and the 850mb chart helps...but a little meteorology knowledge, experience, situational awareness, and the resulting feel for the weather helps more. 

 

estarzinger

Super Anarchist
7,772
1,206
Do you have a boat currently? Just curious.
no, parent are a full time job atm. We made the very excellent decision to keep them in the family, rather than go the typical 'elderly living arrangement'.  It is a significant commitment but well worth it for both them and us.  I have 'plans' when I am free again, but who knows what will happen.

 
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Zonker

Super Anarchist
10,901
7,468
Canada
Having returned at the right time to increasingly help my folks, I can relate Evans. They are still on their own (Dad is 89 and Mom is 88 with dementia) and pretty happy that way, but if Mom goes first we'll talk about him moving into our apartment building instead of a care home.

Way too many people look at one Grib forecast for 1 day or think that one of the Predict wind proprietary Gribs is somehow magical and can give better results. So if it differs from from the GFS or ECMF they believe it.

 

Jud - s/v Sputnik

Super Anarchist
6,937
2,129
Canada
If you want to read the D&UC book, I will happily loan you my copy. Or any of my other books, for that matter.
Very kind of you, Ish - if we make it around the Island this summer (it’s about having enough time), I’ll look you up.  (Likewise if you’re up in these parts, shoot me a message. Will PM you.)

 
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Jud - s/v Sputnik

Super Anarchist
6,937
2,129
Canada
Absolutely true, and too many people have become over-reliant on intra-cell interpolations by fancy software with pretty pictures. Looking at CAPE charts and the 850mb chart helps...but a little meteorology knowledge, experience, situational awareness, and the resulting feel for the weather helps more. 
850mb chart?  (I’ve never heard of them.)  I thought that the “thing” to do, other than using a standard surface synoptic chart, was looking at 500mb charts?  (E.g., some well known books have been written on using 500mb charts for forecasting.)  In a nutshell, how are 850mb charts  different in terms of what they show/allow you to forecast?

 
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harrygee

Member
391
121
Tasmania
You know who to get the best advice from? Delivery skippers.

It isn't their boat, they aren't in love with her and blind to her flaws. They have to get the boat from A to B despite the weather or the owner would be making the trip, so they bang through uncomfortable weather instead of waiting a few weeks for the perfect reach in 15 knots. They sail a variety of boats, not just one.

* pet rant, total n00b sails around the world in a Catalina 30 with orange sails or an old wood schooner or whatever and then becomes an expert in everything and decides his way is the only way to do it. He has never tried anything else :rolleyes:
Most of my deliveries were in unseaworthy boats (by any sane definition), usually single-handed (not my habit to put anyone else through it).  No owners.

No exotic stuff, the usual clunkers, 23' to 60'.  Always looking for the problems encountered on the previous boat, missing the gremlins left by previous owners.  Learning which brokers to trust was a help.

The need to press on didn't extend to going out in stupid conditions but we all get caught sometime.  For all the fantastic claims made by weather gods, I'm not convinced that we've come a long way, to the point that we can predict a specific wind at a certain time in a particular place.  If the prediction doesn't look anything like the basic synoptic chart, I tend to believe the chart.

If some retired boat deliverer wants to write his story, I'll buy it.  Not me, I have enough enemies already.

 

weightless

Super Anarchist
5,608
587
850mb chart?
gfs_mslp_uv850_atl_1.png


 

El Borracho

Barkeeper’s Friend
7,172
3,085
Pacific Rim
One dumb question from the peanut gallery. 

Does boat speed have a bearing in determining if a particular hull form is desirabie or undesirable?

I've been offshore in comfortable boats until the sea state builds to the point the boat is no longer comfortable and you're kinda trapped. When the wave sets are travelling faster than you, the boat goes from comfortable to downright awkward. You're options become limited to just toughing it out until mother nature gets bored and moves onto someone else. 

But if you are running quicker than the wave sets, the motion changes dramatically. The pitch/roll/yaw flattens out and the prior two handed half wheel turns as a wave catches you become an inch or two with a finger. Aside from the comfort level, one major advantage seems to be the fatigue level of the crew drops remarkably, which is another tick in the desirable column. And it seems to open up more options than just taking the flogging.  

So my question is......unless we were capable of doing the speeds necessary to stay in front of dirty sea states when this book was written, are the resultant higher boat speeds from the newer hull /rig designs a big enough of a change to alter some of the opinions and observations made in the books of this era? 

Thanks!

SB
With heavy cruisers following seas always travel faster than the boat. As he hull on these boats gets sucked downwards at speed the boat tends to wallow at the mercy of the speeding lumps. Often with dramatic pitching. With a light plane-able cruiser the waves usually travel faster than the boat but pass underneath much slower, with much less drama. If the boat travels faster than the waves, as happens with the very fastest crewed boats, punching into the back of waves becomes a concern. At best it rinses the decks. At worst the bow stops while the stern continues onwards causing an abrupt change in scenery.

You seem to have a good understanding of the issues. Books say the typical trade wind wave conditions are 6 feet every 9 seconds. I've spent days in those conditions under autopilot, sleeping even, without issues. (SC50) Boat speed varying from 10 to 15 knots. Perhaps 20 on the odd wave or in a squall. The waves usually pass slowly and are sometimes slowly overtaken. Most remarkable: no pitching. I never sail DDW but 30° or more up where some constant wind pressure prevents the roll as waves pass. It is fun. 

The older and slower boats I have cruised behaved comparatively badly as each passing wave toys with the stern. Exhausting indeed as the rudder movements are large and frequent. The apparent wind is high, sometimes wet. The stern rises, the boat turns, then heels, then repeats on the other side, the crew barfs.

The older authors were likely ignorant of the possibilities. Then stubborness set in as their chunderbeast world crumbled. That was way back in the 70's and 80's. One would think the sailing world was past all the discussion by now.

 
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Ishmael

Super Antichrist
58,339
16,228
Fuctifino
no, parent are a full time job atm. We made the very excellent decision to keep them in the family, rather than go the typical 'elderly living arrangement'.  It is a significant commitment but well worth it for both them and us.  I have 'plans' when I am free again, but who knows what will happen.
We lost the last one of our parents last night, we also made the decision to stay around while we could enjoy them or at least support them. No regrets.

 

shaggybaxter

Super Anarchist
4,662
2,755
Australia
Many people under appreciate wave physics. Fully developed seas/waves from 30kt winds will average 17kts speed.  Not many cruising boats can sustain 17kt average . . . and that is not even in a gale when the required speed would be higher (like a sustained 23kt average boat speed) to 'stay in front of the waves'.




With heavy cruisers following seas always travel faster than the boat. As he hull on these boats gets sucked downwards at speed the boat tends to wallow at the mercy of the speeding lumps. Often with dramatic pitching. With a light plane-able cruiser the waves usually travel faster than the boat but pass underneath much slower, with much less drama. If the boat travels faster than the waves, as happens with the very fastest crewed boats, punching into the back of waves becomes a concern. At best it rinses the decks. At worst the bow stops while the stern continues onwards causing an abrupt change in scenery.

You seem to have a good understanding of the issues. Books say the typical trade wind wave conditions are 6 feet every 9 seconds. I've spent days in those conditions under autopilot, sleeping even, without issues. (SC50) Boat speed varying from 10 to 15 knots. Perhaps 20 on the odd wave or in a squall. The waves usually pass slowly and are sometimes slowly overtaken. Most remarkable: no pitching. I never sail DDW but 30° or more up where some constant wind pressure prevents the roll as waves pass. It is fun. 

The older and slower boats I have cruised behaved comparatively badly as each passing wave toys with the stern. Exhausting indeed as the rudder movements are large and frequent. The apparent wind is high, sometimes wet. The stern rises, the boat turns, then heels, then repeats on the other side, the crew barfs.

The older authors were likely ignorant of the possibilities. Then stubborness set in as their chunderbeast world crumbled. That was way back in the 70's and 80's. One would think the sailing world was past all the discussion by now.
Thanks gents, I didn't realise it was that high an average, great info. 

 

AgentLocke

New member
850mb chart?  (I’ve never heard of them.)  I thought that the “thing” to do, other than using a standard surface synoptic chart, was looking at 500mb charts?  (E.g., some well known books have been written on using 500mb charts for forecasting.)  In a nutshell, how are 850mb charts  different in terms of what they show/allow you to forecast?
Not a sailor (still wannabe) but an amateur weather nerd:  At a basic level, 500mb is higher up in the atmo and a lot of the weird "ground effect" smaller details smooth out into a larger synoptic scale pattern that is easier to read.  850mb is kind of a halfway point between surface and upper atmo dynamics.  The way I read weather maps is:


What I mean by that is if I want to know what it will be like at a given position, I'll use the lower atmo maps.  That would give me (if I sailed, which feels more like a fucking pipe dream each year, grumble grumble) at least a ballpark wind-speed/direction.  But it's more difficult to read those lower level maps and estimate what direction the air mass in general is moving, which is what tells me how I can expect weather conditions to evolve from a given point in time.

For me, and other folks with more experience will definitely have better/more nuanced answers, I'm not sure that there is any particular advantage for sailors to using 850mb versus MSLP.  If you're willing to get into nitty gritty details, maybe the 850mb might let you better discern sub-synoptic features like a short wave rotating around a low pressure center?  Not sure anyone is going to do that level of amateur analysis on a cross though; probably easier to identify potential micro-scale features using precip maps.  Either way, the 850mb is still not going to give you a better sense of synoptic scale movements than the 500mb.

 

WGWarburton

Anarchist
993
745
Scotland
For those who have an interest in IOR yachts, I recommend following Julian Everitt on Facebook. He is an Englishman who designed a lot of IOR boats. His comments make it clear that the IOR changed over the years, so all the boats don't have all the flaws and idiosyncrasies. 
Seconded. I have one of his designs, a late 70s designed half tonner. I don't recognise the peanut gallery's "IOR boats suck" characteristics in it.

 (Of course, the really awful IOR boats will mostly have been scrapped by now. The ones still sailing are generally good boats).

 Julian Everitt's commentary on rating systems, yacht design,  keel security,  America's cup sailing etc are well worth seeking out.

Cheers, 

               W.

 
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Bryanjb

Super Anarchist
4,509
319
Various
Really?  It’s going everywhere (which was sort of a problem, when various folks were getting really grouchy several hours ago).

1700 views, 150 posts.  I get 50 cents per view/click, so I’m doing alright :)

I think there are plenty of interesting observations, accusations, and attestations in this thread - it’s a fascinating topic.  Think of it like the peer review process in an academic journal - except the sniping is done right out in the open, not couched in carefully crafted academicspeak buried in an esoteric research paper.  Which is why it’s so good. I’m enjoying this thread - still don’t quite grasp the culture wars of CCA and IOR, but I’m starting to get a better feel for it.

Here’s Dan Spurr (author of “Heart of Glass”, I believe): This second installment of SAIL’s series on the evolution of modern sailboat design focuses on the 1970’s—the IOR decade and beyond
Early on it wasn't, it was just the same ol same ol.  Glad to see it's being well discussed without the typical thread degradation.

 

WGWarburton

Anarchist
993
745
Scotland
The only Julian Everett boat I ever saw up close was an Eliminator 32.   There's a good page on it at https://julianeveritt.com/2017/02/07/eliminator-32/ ... which confirms my recollection of its warped shape.
That's the one- Woofer and Eliminator were both in Ireland fairly recently, may still be. Kermit was there for a while, too, before coming back to Scotland.

 Big for a half-tonner, most of them (including mine) were built too heavy to be competitive but roomy inside, nice wide decks. Could do with more crew weight than we normally have on board.

 Fun to sail- responsive, goes well upwind. Not had any issues with downwind stability. Simple single-spreader rig.

What's not to like?

Cheers,

             W.

 

TwoLegged

Super Anarchist
5,894
2,261
Fun to sail- responsive, goes well upwind. Not had any issues with downwind stability. Simple single-spreader rig.

What's not to like?
Eliminator 32 forefoot.jpg For starters, this forefoot.  Then the stern set up so it can't actually do any work.

I am glad that you are happy with your boat, but it's well loaded with IOR bad attributes.

 

WGWarburton

Anarchist
993
745
Scotland
View attachment 438817 For starters, this forefoot.  Then the stern set up so it can't actually do any work.

I am glad that you are happy with your boat, but it's well loaded with IOR bad attributes.
You don't like the underwater appearance? I'll take that as pretty mild criticism :)

 By "attributes", i was thinking undesirable sailing characteristics: complicated rigs, undersized rudders with narrow sterns, oversized genoas with tiny mains.

 Can you expand on your concerns with the stern shape? Do you mean the underwater profile or the cockpit (or both!)?

Cheers,

              W.

 

TwoLegged

Super Anarchist
5,894
2,261
You don't like the underwater appearance? I'll take that as pretty mild criticism :)

 By "attributes", i was thinking undesirable sailing characteristics: complicated rigs, undersized rudders with narrow sterns, oversized genoas with tiny mains.

 Can you expand on your concerns with the stern shape? Do you mean the underwater profile or the cockpit (or both!)?
Yes, it doesn't have full set of IOR vices.  The lack of massive genoa is very welcome.

But that forefoot isn't just an aesthetic problem; it does horrible hings to the waterflow.  The stern is quite narrow on the waterline, and lacks immersed volume from the rudder aft, so it in practice it isn't all that much better than a pintail.  

 


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