Light Displacement vs. Blue Water?

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tidemaker3

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Can a light displacement boat also be a blue water boat? I'm referring to the Moody 33. With a displacement to length ratio of 205 it is of light displacement but it is also billed as a blue water boat. Is that possible? By comparison, A Pearson 31-2 with a D/L ratio of 278 is of medium displacement but considered a coastal cruiser. I suspect that quality and strength of construction is part of the equation. Or, is it all of the equation? Then what about sea kindliness? Can anyone shed any light?
 
Oh, if it were only that simple...

tidemaker3 said:
Can a light displacement boat also be a blue water boat? I'm referring to the Moody 33. With a displacement to length ratio of 205 it is of light displacement but it is also billed as a blue water boat. Is that possible? By comparison, A Pearson 31-2 with a D/L ratio of 278 is of medium displacement but considered a coastal cruiser. I suspect that quality and strength of construction is part of the equation. Or, is it all of the equation? Then what about sea kindliness? Can anyone shed any light?
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As you might suspect the answer is "Of Course!"
Without regard to any specific design, The strength and design features that make a boat capable of being self-sustaining for an ocean passage do not equate to the displacement #.

Remember how recently a Valiant 40 was criticized for being too light and it had (Oh, the horror...!) a fin keel. :o

Also, try to remember that that 98% of the respondents to your question have formed their Firmly Held Opinions by reading books and from reading postings of strangers on the internet. :rolleyes:

Happy researching.
Lastly, you should try to crew on lots of boats, especially on deliveries. (Nothing against buoy racing, but that's only one facet of comfort and seamanship.)
I have racked up several thousand sea miles in the last 25 years doing deliveries. So far I have formed some opinions of my own -- mainly that lots of different designs and displacements are safe and comfortable at sea.
I have also found that: 1) good shipmates are very very important, 2) I actually like being on the ocean, 3) and really value a comfortable sea berth.

I am half a world away from the home waters for Moody sailboats, but they seem well regarded, FWIW.

Regards,
LB
 
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Don't worry your head about using displacement / length ratios as an overwhelming criteria in choosing a 'suitable' boat for blue water.
Most blue water boats today would have been considered to be extremely unsuitable for this role in the days when EVERYBODY trundled around in Colin Archers or Bristol Channel pilot cutters or similar - but that was mainly because there were no other options available at the time.

Re your Moody 33 - Capn Sensible will be along soon to tell you about his - I think he has lived aboard her for the last 15 years or so, and clocked up at least 10 trans-atlantics in this time - so that should speak volumes as to the suitability of a Moody 33 for handling blue water.
 
Plenty of them have done serious passages. Looked at a Moody 333 (same hull) which had just returned from the Caribbean, I think the new owner was going to take her back. Personally I would be happy with a well found Moody 33 for bluewater duties. You don't necessarily always need a full long keel and a weight north of 12 tons. We have a Westerly Discus which I suppose is Westerly's version of the Moody 33 (albeit aft cockpit) and would take that anywhere. I suspect it would rate with a similar D/L ratio. Not forgetting when Angus Primrose unveiled the Moody 33 in the 1970's, people were shocked at the volume in the hull and reckoned it would never sell. He took a factory example across the Atlantic and proved the boat's pedigree. I am sure he would have done more with it if he hadn't been washed off the back of it while sailing down America's East coast.
 
Angus Primrose

Is this a known fact re. Angus Primrose's demise ?

I thought he was lost while singlehanding and hit by very severe conditions, is that wrong or was there some evidence he'd gone off the stern ?
 
I assume you are also talking about long term cruising when you say 'blue water'.

I think it far more important to make sure that the boat has capacity to store all the cruising clobber, say 72 hrs of fuel, and 400 ltrs of water, easily within the boat ..... and then for the boat to perform without over-stressing the rig, hull, and steering gear.

Other good attributes would be moderate to deep draught, say 1.6m; a deep bilge to prevent bilge water from contaminating the stores, and a sugar scope or another way of easily entering and exiting the water (although a dinghy can also be used).

I think any 32 foot sailing yacht would have a hard time meeting these requirements, but I've also seen many people doing circumnavigations on 27 footers.

In the end any boat is a compromise, and you have to pick the best available ..... and learn to live within its limitations.
 
TradewindSailor said:
I assume you are also talking about long term cruising when you say 'blue water'.

I think it far more important to make sure that the boat has capacity to store all the cruising clobber, say 72 hrs of fuel, and 400 ltrs of water, easily within the boat ..... and then for the boat to perform without over-stressing the rig, hull, and steering gear.

Other good attributes would be moderate to deep draught, say 1.6m; a deep bilge to prevent bilge water from contaminating the stores, and a sugar scope or another way of easily entering and exiting the water (although a dinghy can also be used).

I think any 32 foot sailing yacht would have a hard time meeting these requirements, but I've also seen many people doing circumnavigations on 27 footers.

In the end any boat is a compromise, and you have to pick the best available ..... and learn to live within its limitations.
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My Moody 33 had a 40 gallon water and fuel tank - I've since replaced the original steel fuel tank with a 91 litre standard plastic tank with the calorifier alongside so gaining extra storage above the tank. To increase fuel you could carry extra 20litre jerry cans. I would have no hesitation in taking it long distance cruising - several have done this. It is very user friendly, not over canvassed, very strong and has lots of storage and would be ideal for a couple long term cruising.
 
Seajet said:
Is this a known fact re. Angus Primrose's demise ?

I thought he was lost while singlehanding and hit by very severe conditions, is that wrong or was there some evidence he'd gone off the stern ?
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Angus Primrose got caught out by a tropical revolving storm in the Gulf Stream.

The boat apparently was pitchpoled and he got his crew into the life-raft, went back for something in the boat, and didn't make it back to the raft in time, before the boat capsized.

As something similar happened twice toTzu Hang and the Smeetons, (Tzu Hang was definitely an Heavyweight) I don't think the example is valid.

In fact the question appears pretty pointless as the OP seems to be conflating weight with seaworthiness, a quite clearly incorrect assumption.
 
I wasn't asking in relation to the Moody 33, just to get the story of Angus Primrose's loss straight for personal interest; as I say I'd been under the impression he'd been singlehanded.

A lot of boats have been lost which might make better comparisons than Tzu Hang off Cape Horn, though I agree it does disprove the 'tough heavy boat can take anything' theory; snag is the 'anything' the Smeetons were facing probably would be survival conditions for any vessel !

If discussing heavy weather, for what it's worth I've long thought crew size & strength is probably a deciding factor; with a rugby team for a crew one can keep steering actively...
 
Hiya. Indeed we have lived on our Moody 33 for almost 14 years. She is a 1977 version and still going strong!

Have done the Atlantic 4 times on our boat, the other times were deliveries. I feel absolutely comfortable offshore on our boat and she has handled some quite bad weather, always on the west to east crossing. Oh, edit, we got a bit of a slap from Delta a few years ago, on the way to Cape Verdes.

Just stick a hydrovane on the back and roberts' your fathers sibling.

There is also plenty of room for my wife's shoes.....

Hope this helps!
 
Dreams are made!!

555_5522.jpg
 
The report I read of Angus Promrose's loss said he and one crew were caught in a gale several hundred miles off the US east coast, after the 1980 Annapolis Boat Show. The crew member survived in the liferaft. He reported that when the boat capsized it remained inverted for 'about five minutes' and when it came upright it was so full of water that it could not be saved.
The light displacement combined with excessive beam was blamed for the inability of the boat to right itself quickly, in some reports.
 
From what I've seen the majority of ARC boats are light displacement. However, once you get out into the boonies you see very few of them. We've been in anchorages where 75% of the boats have been metal and 60% with two masts.

There are two issues about lightweight boats. First their motion and slamming makes them much less comfortable than heavy displacement boats. Second they can and do lose their masts, keels or get hull damage in heavy weather, particularly in large seas with cross swells.

Having said that from my calculations the percentage of lighweight boats that do get damaged is between 2% to 4%. On the other hand I prefer to sleep at night so a lightweight boat would be a no-go. One truism to bear in mind is cruise for long enough and you will hit something or something will hit you.
 
One other thought is, I don't know if you have done a 24/48 hour paasage in a light boat. If you haven't do that and then try to do the same passage in a heavy displacement boat. You will be staggered at the difference - we were.

>I thought he was lost while singlehanding

When we were in the Caribbean (for over 6 years) we kept count of the number of boats and their crew numbers that came up on boat watches i.e overdue. 25% of them were single handers. My guess would be that less than 1% of cruising boats are single handed.
 
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KellysEye said:
There are two issues about lightweight boats. First their motion and slamming makes them much less comfortable than heavy displacement boats. Second they can and do lose their masts, keels or get hull damage in heavy weather, particularly in large seas with cross swells.
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Can't disagree about the motion etc. but there is a point of view that says a light displacement boat without too much keel or ballast will have less grip on the water and will yield to the seas, getting thrown about by them rather than sitting there and taking it on the chin. In Maurice Griffith's writings about shoal-draft yachts he quotes several instances of American centreboard cruisers riding out conditions board-up which had overwhelmed deep-keeled heavily ballasted yachts of the same or larger size.
 
>centreboard cruisers riding out conditions board-up which had overwhelmed deep-keeled heavily ballasted yachts of the same or larger size.

The great majority of American yachts are heavily built, thus can survive most things. We have a heavy displacement boat and in extreme conditions we would use a parachute anchor. In a lightweight boat I would use drogues to protect the rudder, albeit there is a risk of the cleats pulling out so the bridle would go to cleats then to winches.
 
tidemaker3 said:
Can a light displacement boat also be a blue water boat? I'm referring to the Moody 33. With a displacement to length ratio of 205 it is of light displacement but it is also billed as a blue water boat. Is that possible? By comparison, A Pearson 31-2 with a D/L ratio of 278 is of medium displacement but considered a coastal cruiser. I suspect that quality and strength of construction is part of the equation. Or, is it all of the equation? Then what about sea kindliness? Can anyone shed any light?
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This is a very confused topic. Is a lighter-built vessel not fit for other than estuarine duties? Must something for offshore use be built like a Thames barge? Must an ocean-going boat have a wine glass X section for stability? Is form stability a snare and delusion, a toy of the racing classes? etc etc

Some things are broadly true in this debate - eg boats are built to withstand waves and weather. The number of vessel breakups is minute compared to the boat park in use. And dismastings happen to all classes of vessel - carry too much canvas and the rig is a gonner etc. A generation ago a 40% ballast / displacement ratio was considered essential if a boat was to go offshore; today that ratio has been moderated and sensibly so. There never was hard science behind the claim - such forrmulae are not to be taken as absolutes. It's a multi-variate world out there.

Handlability and sailing qualities are relative not absolute. The EU rating system, A for ocean etc, is urged on us a standard when it can be no more than a rough guide, an entreaty to take care when choosing a boat. Anyone with sailing experience knows this to be true. In the hands of a well tempered crew a so-called light-weight can cross oceans, and many have. There is no reason for us all to drag along tonnes of ballast "just to be sure"

Moody build good boats, arguably on the lighter side (it's called more responsive design!); they do what it says in the literature. The rest is down to the crew, method of sailing, and the degree of creature comfort desired. You can pay 2 or 3 times the Moody asking pice for "something more substantial" - but it's all in the eye of the beholder, whatever justification employed by builders trying to widen their niche in the market.

But you knew that already, I guess....

PWG
 
tidemaker3 said:
Can a light displacement boat also be a blue water boat? I'm referring to the Moody 33. With a displacement to length ratio of 205 it is of light displacement but it is also billed as a blue water boat. Is that possible? By comparison, A Pearson 31-2 with a D/L ratio of 278 is of medium displacement but considered a coastal cruiser. I suspect that quality and strength of construction is part of the equation. Or, is it all of the equation? Then what about sea kindliness? Can anyone shed any light?
Click to expand...

I've no issues with most of the preceding erudite discussion but, as something of a units pedant, I have always had an issue with bare numbers like those quoted - sadly common practice in boaty comics. As stated here (and elsewhere) the number as presented is apparantly dimensionless, but clearly that cannot be the case since it is a ratio of physical quantities: displacement, i.e mass, divided by length. Since there is a quite wide choice of units for each of these, the presented number only makes sense if dimensions are stated explicitly, e.g. kg/m, tons/ft, tonnes/cubit or whatever.

Without supplying the necessary units it is as meaningless as stating that a motor car was doing 100. (mph? kph? ft/s? furlongs/century etc.)
 
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