Hull Shapes and Behaviour in Heavy Seas

[NevisDog]

Originally Posted by psk125

Knowing that it's the middle of the sailing season down under makes it hard to suggest stopping to read this before proceeding:
Desirable-Undesirable-Characteristics-Offshore-Yachts

I just read through a section on hull design and to me that book seems utterly confusing. No doubt it's a great read for designers and bar-stool discussion but for practical assessment of which boat to buy... not my cup of tea.

Read Kretschmer's 'Sailing a Serious Ocean' for recommendations and reasoning - much simpler and far more fun.

[Mr B]

Portland is freezing wet and cold during winter,
Its very hot and windy during summer,
If the steel thickness is less than 3 MM walk away, Under 3mm it bends and flexes, No matter how you stiffen it,
It dont have enough strength in itself to hold it straight. It will just buckle,
If you want to truck it, The house movers here where I am in Hastings, Victoria can do it for you,
They are about to move a house boat thats being built here to Eildon weir,
Its about 25 metres long and 8 metres wide and 3 storys high,
Same company has moved my 34 foot cat 3 times,
Specialised trailer that lifts boat and houses with out cranes,
This piccy is the pilot boat they shipped to New Guinea, After refurbishing it here,
I also moved my boat from Port Stephens in NSW to Hastings, Victoria, It cost me $8000-00 to truck it down,

Cheers, Brian,

[MartinR]

Originally Posted by NevisDog

Bluewaterboats.com: "The Adams 13 is easily handled, rather nimble and owners report it as being fun to sail. The boat’s motion is comfortable and seakindly, and it is said crossing oceans in her can often be less effort than a 36 foot yacht. Not surprisingly with such a narrow hull and light displacement, the boat is easily driven..."

This seems hardly credible, incredible... she looks and sounds like a ULDB, which would be "easily driven" but very twitchy and taxing to handle, even with a full-on racing crew. A youtube video shows her sailing comfortably downwind in Bass Strait in 50 kts following wind but I hate to think how she'd handle if forced to heave-to or (God forbid) beating back into it. Accommodation seems to consist of 2 sea berths, 2 forepeak berths that are untenable except in harbour, and everyone else must double-bunk or move out of the way when occupying the saloon. Loaded with the normal cruising/liveaboard gear (if indeed there is anywhere to stow that gear), she'd no longer be "easily driven" either. As a family cruiser, this boat has everything against it and nothing in favour.

Brutal. Be careful what you wish for...

She just about qualifies as an ULDB. As she is narrow and has a centreboard (I think), she could be relatively sea kindly. As for nervous to steer, my boat is an ULDB, much more extreme in D/L than the Adams 13, and she tracks like a train. Only very small input needed at the rudder. Incredibly easy to control in all conditions. I can easily sail her single-handed. All about balance of hull, keel and rudder. Narrow boats tend to do this better than the modern wide beam racers. t

But the Adams as a family boat is a little bit the opposite as the steel boat previously mentioned. Faster motion, more performance, cramped accommodation, even though performance will take a big hit once loaded for cruising. With these kind of boats you have to weigh every pound, and "good to have" items stay off.

[wingssail]

Originally Posted by Metal Boat

That information right there is the info that I am after. I like the Adams 13 they are a fast boat but swing keels always make me nervous as it is a point of failure. The info I read on the adams 13 was this

The Adams 13 Metre Sailboat : Bluewaterboats.org

lauding it as a bluewater cruiser

I am still tempted to jump in a car and drive to Portland that steel hull is still a brutal boat.

Metal Boat, You are right to g look at that boat, but please dismiss the concerns you've heard rom Cpt Pat. We've taken this thread way off the subject, since you are asking about the 63' hard chined steel boat, but I caution you from taking ANYTHING that Cpt Pat has said with any kind of conviction. And I just cannot let his wild claims go un-answered.

He's wrong, totally wrong. Every serious sailor I know, plus my own experience, would totally disagree with him. About the Adams, my friends sailed their steel Adams 13, Sue Ying, from Perth Australia to the Philippines and back, in a variety of conditions, and had nothing but good things to say about this type of boat. My own experience in 55,000 miles and a circumnavigation, to say nothing about sailing a Sydney Hobart on a similarly configured 65' race boat, and plenty of other passages on a wide variety of boats, including full keeled cruising yachts, and the opinions of ALL serious ocean sailors I meet, say that a good performing boat with a fin keel and a powerful spade rudder, is just as good, and in may ways better, than any alternative Cpt Pat can mention.

Specifically, his claims are all bogus,

Originally Posted by Cpt Pat

"Its keel looks like the worst possible form for stability in heavy seas. It's a racing boat that would be only marginally stable even in light seas". (Wrong, my friends who sailed their Adams, Su Ying, around the South China Sea and between Australia and the Philippines would disagree, they loved their boat's heavy weather characteristics)

"Unless you're dodging closely spaced icebergs, what you want in heavy seas is a seakindly full or modified-full keel that has high yaw stability that will tend to itself, especially when hove to " (Wrong, any boat will yaw once the waves become longer than the length of the boat, and a boat like this Adams or any fin keeled boat with a spade rudder, can return to its course quickly and with little effort, due to the powerful rudder effect, and hove to, they will be docile and comfortable. I can attest to that.)

"with someone continually swinging the wheel to keep it on course" (BS, Total BS, These configurations maintain course with the most insignificant rudder corrections, because the BOAT WILL RESPOND).

'You can expect to come to a dead stop in wind-shadowed wave troughs, regardless of your point-of-sail, and that boat has no stability at all when not moving at speed through the water. In really heavy seas, it's doomed." (I'm sorry Cpt Pat, the is ALL FICTION, nothing more)

"I don't want to think about what will happen when the boat encounters a swell that exposes the rudder. " (In 32 years with my boat, in some horrendous sea conditions, such as exiting Havana Pass in New Caledonia, with an ebb tide against the SE Trades, when the waves were so steep that we thought we'd fall right down on top of the boat ahead of us, there was no loss of steering with our spade rudder)

"Basic rule: the harder it is to dock the kindlier it is at sea." (Hogwash, this sounds like an excuse for a boat you can't safely dock)

"That boat will do pirouettes around its mast, which in nice in a harbor - but truly nasty in ocean swells." (in your imagination)

"And, if you intend to cruise, don't buy a racing boat. " (I'd say, if you intend to cruise, and you want to sail instead of motoring, buy any boat which will perform, race boat or otherwise, and avoid the slug which can't actually sail)

So, Metal Boat, chose well, listen to the many intelligent commenters on this thread, but do not be swayed by the highly opinionated, but wrong, folks. Like Cpt Pat, who maintain that they know every thing and that only a boat like their own is suitable for cruising.

[Jim Cate]

Metal Boat, let me add my agreement to what Wingsail has said here. And, to put some more perspective on this discussion, between Wingsail (Fred) and Ann and I, we have sailed over 200,000 miles in fin keeled boats, both ex-racers and purpose designed fast cruising boats which don't meet any of Cpt Pats requirements.

The Adams 13 may be too small below decks to meet your requirements... it probably is! But it is not a death trap, and there are several that we know that sail in the waters to the south of Tasmania. Their owners and crews would be astonished to know that they have cheated death each time they return from a jaunt into the Southern Ocean or Storm Bay.

In the long run, you will choose a boat that you fancy. Don't let overzealous folks who can only see one possible choice of designs sway your thinking.

Jim

[MartinR]

Actually this Adams 12 looks very good. I like the interior. It seems more beamy than the 13. There are pilot berths, big plus! I am sure these boats are perfectly seaworthy, but maybe not as sea kindly as the heavier boats. The most important factors in sea-kindliness are beam, which is a big negative, deplacement, which is positive, height of center of gravity, meaning the higher the ballast the slower the movement of the boat. In older times, like in my previous boat built 1902, the ballast was actually inside, and she was the perfect sea boat. If I see this correct, the low displacement in the Adams 13 was compensated by slightly narrower beam and higher placement of ballast. In my view a good compromise. Kind of my present boat, but she is much more extreme.

Is the Adams 13 a centreboard or a lifting keel? Makes no difference. With the shallow draft you could come into places most of us can only dream of.

I like the factor that the OP is into different kinds of boats. Only he can in the end decide what he wants.

[Metal Boat]

Ok Guys and Gals I'm feeling kinda gun shy and embarrassed at the moment for a number reasons not the least being I don't want to start a flame war.


Also by my own hand I have allowed the thread to drift because in a sense of defeat I have surmised about other types of hull and brain farted them into the thread. Yes I am erratic because I am trying to marry a number of different outcomes and possibilities into a plan that has not yet crystallized. I apologize for my vacillation.



My limited knowledge of the Adams types were that they were a long thin hull that performed very well but more leaning to towards performance than cruising. I have to say that at first I felt a little foolish when the Adams 13 was shot down. I respect the school of thought that likes a long keel, I am a traditionalist myself, but I am not prepared to write off newer design philosophy without examples of practical testing. How we imagine an engineering outcome and what happens in the real world are two different things.


If I had enough money I would put the wife and I on a 65' trimaran and pray I don't get caught out above 50 knots, but if you do something enough times eventually the day will come. I need something in between, nice and heavy but still able to achieve a reasonable turn of speed in all kinds of conditions.



There are enough Adams designs around to form the beginnings of a statistical pool to analyze failure rates. When I look at an aircraft I ask the question, how many were manufactured, how long were they manufactured, what is the total of hours flown by the fleet and how many of them had the wings drop off? I feel there are enough Adams in circulation that even knowing nothing about yachts that they were worth considering. Now performance is relative, if I only want to put two people on a yacht with minimum hand luggage for a shorter period of time it may suit, but I have to be real with myself I need a F250 turbo diesel not a front wheel drive hatchback. I need to cart enough stuff to be self sufficient. Enough of the Adams



Yes I have boat lust for a big steel ketch, not necessarily this particular ketch but this particular concept. I just missed out on a Halvorsen Freya 53 Steel round bilge last week, listed for 43,000 much closer to home. It was ideal but it sold before I could even get in the car. I even had the motel room booked and was due to travel the next morning, thanks mate you know who you are.



I have noted the warnings from all involved and I can see the risk both from the boats (engineering + market values) point of view and also how my family will react. I didn't really want to bare my private life on the Internet but I see now that certain objectives I have may not necessarily seem logical to others. I have lost my medical to fly and let me tell you I am not happy about it. I am a bird with clipped wings and I have fallen. Aviation is a very selfish pursuit, and in many ways I deserve it after years of being away from home.



I have a redundancy which will allow me to make an initial purchase of a yacht up to about 70,000 with 30,000 remaining for emergencies. I also have super which I can get limited access to for medical reasons for daily income. Clearly this is no where near enough to buy a quality 60' boat that is big enough to house us. I have one investment property that I am prepared sell in time and I will put a tenant in my house but I need to transition first and be secure on a yacht. So buying something to fix up makes a lot of sense in my case.



Time is partially on my side and I am sitting at home going stir crazy. I am sick of wankers in traffic, thieving bankers and salesman, government bureaucrats (especially scum from CASA) etc etc etc and one way or another I am going to go sailing and see the four corners of this earth that really matter. This yearning did not start yesterday I have been thinking about this for 25 years and the medical issues have jolted me into realizing that I am on the downside of the ledger.



I will be the first to admit that I can be arrogant and foolhardy. I know others have crashed and burned. I can see the risk of failures in expensive hardware such as the engine. But on the whole I am not overly concerned with the Lister, unless it gets to the point where the crank had to come out which means the block would have to come out. I could see a pot failing which for me is a walk in the park, but bearing failure in such an engine is pretty remote and would show in oil samples. Same with the gearbox.


The interior I would enjoy fabricating. I have spent my career fabricating bits of aluminum to the thousandth for other people and I have all the tools surely it cant be that hard to fabricate marine/form ply. I can see money in materials but there is no way I would pay someone to do it. Same goes for painting, someone said imagine sitting with a hand sanding block looking at the hull. I cant imagine it because I would be using an industrial air driven sander and petrol pressure washer/sandblaster that I already have. If I have to get the tools out and dirty the spray gun whats an extra 10' to paint.



Rigging is a concern for me because I know nothing about how it is put together in unison, can you simply disconnect one cable and replace it without everything falling down as you clamber? I have fabricated lots of control cables albeit of a much smaller diameter. I am SH*T scared of going up the mast, unbelievably I am scared of heights without wings. The little research that I have done indicates that gal cable is relatively cheap, and I may be able to reuse some of the old fittings. I am sure with a little thought and some triage I will be able to replace the standing rigging over a period of time (subject to initial inspection of course).



Sails are the one thing that really worry me in terms of engineering. I have absolutely no desire to fabricate sails and I will despise even making simple repairs, I can say that with certainty. The condition of the sails is critical. At this point I would just want to get the boat home by depowering the rig if necessary. (don't worry I will be hiring a Delivery Skipper to hold my hand) In the immediate term, say the next 2 years I really don't care about sailing, I will be happy jaunting around Moreton Bay even if its just motoring around whilst I get the rig together. Apparently most of the sails are in good condition but we will see.


It goes without saying that the hull must be structurally sound, without any critical corrosion anywhere. The shipwright who has worked on the boat who has no reason to lie,and probably will get some business from me on his slip is confident that the hull is sound. The interior has supposedly been coated in epoxy from day one and if this is the case chances are good. I don't care about the lack of pedigree of the hull just about how it handles and its strength. I can see a path check these things with due diligence.



I have decided on a path forward. Further speculation as to the condition of the vessel is now unhelpful. I am going to approach the shipwright tomorrow (he and I had a long conversation a few weeks ago and he was extremely helpful and loved his sailing) and get him to go over the vessel and take relevant pictures and find immediate failures. I am not seeking a survey just to tell me glaring problems without any liability. I want to know if the batteries are stuffed and if he can get the engine running and get water out of the bilges and have a good look. I figure if I drop a few hundred and the boat is really unworkable it will be a small wager to determine whether to proceed. Don't panic I am not going to rush into this, once I have the results I will discuss,


cheers all and once again keep it coming the more angles the better....

[Metal Boat]

Originally Posted by MartinR

Actually this Adams 12 looks very good. I like the interior. It seems more beamy than the 13. There are pilot berths, big plus! I am sure these boats are perfectly seaworthy, but maybe not as sea kindly as the heavier boats.

Damn I am hopeless OK I admit it I spent an hour on the phone to the broker today about this boat. It is certainly in the mix. Only concern is no shower, must have hot water and water maker. I think the Adams 13 is a lifting keel?


One of the things I am thinking about is buying something like this and using it for family fun and school holidays and then selling it to buy something bigger after I kick the kids out. It is located near (relatively speaking) to the ketch and I am certainly thinking about looking at it in the same trip. I really need some perspective on size. We as a family are still deep in discussion and as stated I sincerely apologize for the thread drift and the vacillation. I should have titled the thread what boat do I buy....


I am taking the wife soon to look at boats we cant afford just to get a perspective on interior.....


P.S. What is a pilot berth? And ULDB?

[MartinR]

pilot berth, the berths above the settees in the saloon.
ULDB: Ultra light displacement boat D/L <100

Ask the shipwright to check if the sails are salvable, the staysail is obviously shot, but maybe the rest is repairable enough to sail her. Big cost in new sails, but repairs are fairly cheap.

Also check the rigging, a little rust on galvanised wire is no problem, but not too much. You can actually load test this easily by tightening up the shrouds to above 40% breaking load. If they are good for this, the boat is fairly safe to sail. Galvanised wire is cheap and if you learn how to splice it, replacing is no big deal.
And- no - you can not just take a wire off without thinking it through. You have to climb the mast to do that, and you want the mast to be safe enough. The important parts are upper shrouds, forestays and backstays. Intermediates and lowers are only to keep the mast in column and normally not heavily loaded.

Check running rigging and blocks, there is much money here. One block sheave for a big block is typical 400$ US.

Hull I am not worried about, the boat looks fair enough. Some corrosion you will find of course, needs to be sand-blasted and painted. Otherwise it will reappear.

Good luck with both of these boats. Both should do for a live aboard for 6.

Do not take your wife to look at nice interiors Just a tip

[NevisDog]

Originally Posted by Metal Boat

... We as a family are still deep in discussion and as stated I sincerely apologize for the thread drift and the vacillation...

No problem, we've all been through this phase (unless we got really lucky) and a good old argument over design is nothing new here - don't apologise for the mistakes of others (me included) and the title of your thread provides an ideal vehicle for this discussion. I feel partly responsible (sorry Capt Pat - your advice seemed sound and logical to me) - I took one look at the Adams and thought "Fastnet Race disaster"; Marchaj's "Seaworthiness the Forgotten Factor" and immediately damned the boat.

So if you don't object (you can skip this discussion if you like), it may be instructive to ask Jim and Martin where I went wrong - why, with their hands-on experience of light displacement cruising, they believe a boat like the Adams, with its ballast clearly set so high in the hull and its forefoot so frighteningly shallow - why they believe such a boat would perform better than the boats that suffered so terribly in the Fastnet Force 10 storm of 1979, which is basically why Marchaj's book was written.

I agree with Martin that having the ballast up inside the hull makes for a far more comfortable ride, downwind in a seaway, but the cost of this comfort is the loss of ultimate stability - the angle of vanishing stability will be reduced, perhaps to the point the yacht is no longer safe in a knockdown. Sure 43ft of boat is less of a concern than most of the Fastnet failures but it might ensure the boat fails to meet European "Cat A" standards for offshore, and those safety standards are considered an absolute minimum by many/most knowledgable designers. Several 'tall ships' have come to grief with disastrous consequences due to their internal ballast.

I hope we can keep this discussion constructive and informative - have no wish to diss anyone or their viewpoint but I would like to understand the divergence of views.

[MartinR]

Actually, these boats are not at all like the Fastnet boats. Very different designs. The Fastnet boats were IOR, quite fat actually. Not the most seaworthy designs. That said, the boats were less of a problem than the crews. If they would have been actively sailed, most would probably have been OK. The boats that actually continued racing were much better off. Lying hull in these conditions is a viable option with a Colin Archer or a Pilot Cutter, but not with a 30´IOR racer. The same goes for all modern fin keeled boats. To be safe in weather they need to be actively sailed. They need enough speed downwind to keep flow over the rudder, or upwind, they need to be nursed over the waves.

My boat definitely exceeds CAT A standards for stability by a big margin, and I am sure the Adams 13 does this also. Even completely ballast-less boats can do this if correctly designed, like some sharpies for example. The advantage with narrow boats is that they have bad inverse stability, so they right themselves much easier. A narrow coachroof helps here.

Internal ballast has been very successful in for example Bristol Channel Pilot Cutters, which were and are extremely seaworthy boats. In other boats, like for example the older generation of American fishing schooners typed on Baltimore Clippers this was not so successful. these boats were heavily over-canvassed, and small mistakes from the crew could easily end in disaster. They became much safer after changing to external ballast.

It is the whole that makes the boat. And in the end it is the men and women in the boat that are the most important factor.

I have owned heavy, long keeled, gaff-rigged boats for most of my life. And I love these and I have found them very comfortable and seaworthy. But I have always liked speed and racing and this time I wanted something different. For seaworthiness I have no reservations about my current boat, but I am aware that I can not just heave too in a storm and go down, sit at the table and play cards, which worked in the gaffers. So, personal comfort is sacrificed for performance.

[NevisDog]

Originally Posted by MartinR

Actually, these boats are not at all like the Fastnet boats. Very different designs. The Fastnet boats were IOR, quite fat actually. Not the most seaworthy designs. That said, the boats were less of a problem than the crews. If they would have been actively sailed, most would probably have been OK. The boats that actually continued racing were much better off. Lying hull in these conditions is a viable option with a Colin Archer or a Pilot Cutter, but not with a 30´IOR racer. The same goes for all modern fin keeled boats. To be safe in weather they need to be actively sailed. They need enough speed downwind to keep flow over the rudder, or upwind, they need to be nursed over the waves...

An excellent summary IMO (though some 'moderate fin and skeg' designs may behave quite differently from those 'deep fin and spade' when hove-to). I think this should be of help to the OP, with his family as crew. In summary: a traditional, long-keeled boat allows you to go below and play cards in a storm; a ULDB really needs to be sailed actively through that storm. (I hope that's a fair summary.)

"My boat definitely exceeds CAT A standards for stability by a big margin, and I am sure the Adams 13 does this also..."

I'd be less certain of the Adams - sure she is narrow (unlike the IOR boats) but the ballast seems awfully high. I'd want to check the calculations on that - comfortable ride in a lightweight boat can be a good indicator of lack of ultimate stability, especially with any 'cruising' additions and carrying a full cruising complement and gear (for which she was never designed), I'd be concerned. No, I'd be more than concerned.

[Don C L]

Probably plenty of multihullers here who would differ with you on the lack of safety in a 65’ trimaran! Btw, 65’ in a monohull is really big, but 65’ in a trimaran is enormous... but it would be good for a family of 10 or so...
I love my little monohull, but I confess a lust for some Newick trimarans.... I’d say a good deal of safety in ANY design boils down to the level of preparation in both boat and sailor...

[JPA Cate]

On our present boat, and on the IOR boat that preceded her, I found the motion in strong winds when going to windward much like being hove to. The trick is to do your fore-reaching SLOWLY, so that the boat stays heeled over from the breeze, but what you experience in the way of motion is just the floating up and down the waves, while heeled. This is not "actively sailing the boat," as the wind vane or autopilot will be steering, the sails reefed, or (in our case) furled, and pretty well minding herself. One is, of course, keeping watch.

Really, Big Metal would do himself a favor to just get out and sail a lot, on OPB's (other people's boats) and experience different boats and how they are handled.

@BigMetal: You're on the steep part of the learning curve. If you're still planning to buy that huge ketch and gut her, you're going to need to find out about what angles of seat backs are most comfortable (ergonomically) and to understand what will work in a seaway, and it is an enormous job you have ahead of you. It isn't about the actual building, which may be a lot of fun for you, but getting a good design for a workable interior, isn't all that easy. This is not to discourage you, but to encourage you to look deeply at the subject before you commit.

Ann

[Cpt Pat]

Metal Boat: Don't be afraid of starting a flame war here, the discussions thus far have been very civilized.

When I look at an aircraft I ask the question, how many were manufactured, how long were they manufactured, what is the total of hours flown by the fleet and how many of them had the wings drop off?

That's good analogy. If you were looking for the best aircraft to tour the world with your family by that criteria, you wouldn't be wrong to choose a DC3. They've been in operation for 70+ years and are still flying scheduled commercial routes in part of the world. I've hauled skydivers in one, and I could trim the controls, walk back in the cabin, and take a nap without worrying that some minor turbulence would upset the aircraft. It's super stable, but also a gas guzzling slug. Why, because its designers traded-off speed for stability. Examples: look at all that dihedral in its wings that sacrifice lift for stability. Look at that huge vertical stabilizer that adds drag - but allows the plane to fly on a single engine without a huge compensating rudder deflection. Large and heavy main landing gear wheels that add lots of weight, but prevent dropping a wheel into a rut on dirt runways. It wasn't designed for speed, it was designed for stability and robustness. And you could put one of your children who couldn't reach the rudder pedals at the controls with only the instructions to: "if an engine quits, close both throttles and wake me up, " before you go take a nap.

On the other hand, if you could fit your family inside an Extra 300, then all flying will be solo - single handed. It has neutral stability - it flies inverted just the same as right-side-up, and it would be a handful for even you to fly because it requires constant control input. I flew one cross country once, and I could barely avert my eyes to look at the chart. "Where am I? Let's look at the chart in my lap." Shadows immediately start to shift across the chart, and in a few seconds I'm in a steep spiral dive. Recover, look down again, and the chart floats in mid air as the nose pitches toward the ground. The Extra 300 is designed for competition, not for going places.

The same holds true for boats. Which experience do you want to subject your family too? A slightly slower (up to hull speed - then there's no difference) cruising boat, or a high performance competition racer that only you will be able to handle in all but the most benign conditions? Are you planning a family adventure, or a single handed cruise where you bring our family along as passengers?


There's a design spectrum: at one end is stability, and at the other end is speed. Only you can decide where on that scale you want to be. But if you're just starting out, I strongly recommend staying that the stability end.