Best hull design for comfort at anchor?

[Curmugeon]

Take a look at the Brewer Comfort Ratio.It takes many variables into account.

[Curmugeon]

To find the Brewer Comfort Ratio check https://www.tomdove.com/sailcalc/sailcalc.html

[Jweyndling]

A catamaran is without doubt the way to an achieve what you are looking for. I used to have a 47’ monohull and frequently had to put up with rolling at anchor. Since switching to catamarans I rarely have that problem. Also, it’s just a much better living experience on a cat👍😊

[CarlF]

Originally Posted by Curmugeon

Take a look at the Brewer Comfort Ratio.It takes many variables into account.

The Brewer Comfort Ratio is intended for monohulls. It’s also for comfort underway not at anchor.

[barnakiel]

1. a cat rather than a mono,


otherwise, if mono, then :



2. big and heavy rather than small and light,
3. beamy and flat rather than narrow and deep,


A side note - no overhangs, or at least no low lying overhangs - as these SLAM.


Another side note - rode attachment point low on the bow, NOT on the deck.


One other note - low windage, and minimal windage forward - boats with less windage sail less at anchor. Boats with more windage well aft tend to sail at lower angles.


Last but not least - a comfortable step-of-the-dink platform - e.g. boats with high topsides and no landing platform are very hard to climb onboard if you arrive when the anchorage is very choppy.


good luck, enjoy your anchorages !!!


barnakiel

[barnakiel]

PS Brewers comfort ratio is imho a big mistake. It seems to disregard hull shape. And hull shape is of paramount importance - think of slats floor inflatable vs. a narrow rowing skiff.


And likely twice wrong for boats at anchor that are not carrying any canvas to slow the roll.


b.

[MJH]

Originally Posted by caribbeancruise

My wife and I have been cruising on and off for the past 8 years and have spent the last 18 months on the water almost full-time.

We recently sold our 2010 35’ production boat (monohull, fin keel, spade rudder, flat bottom, carries width of the beam all the way aft, high topsides). As we’re looking for our next cruising boat, oddly, one of the most important things at the top of our list is comfort at anchor in high winds.

While cruising for 3 months in the Bahamas earlier this year, we found ourselves staring out of our portlights in one storm after the next wondering why we were healing at anchor and swinging almost through 180 degrees. We could dampen the swinging a bit by running a bridle to an aft cleat, but we’d still swing at least 45 degrees on either side of the wind. Sometimes I’d even put out a sliver of jib and countered with the helm hard over to one side trying to lay ahull, but still, just barely a measurable difference.

The cats in the anchorage looked like they were having a comfortable time and barely noticed the frequent 20-27 knots winds.

We thought, ok easy choice, we’ll get a cat. But, after talking to owners and watching several videos of different anchorage scenarios, we’re not sure that is the answer. They seem to bounce quite a bit in a short chop while at anchor. Most didn’t seem to swing much, though there were a few that did.

We also noted that we never encountered these issues on our 1991 30’ Tartan even when winds reached up into the low 30’s. Our memories could be short though; maybe we just didn’t worry as much about it.

If comfort at anchor (defined as less swinging so we’re not going beam on to the wind and waves every few minutes) was the top priority, would a better hull design be the answer? Or is a heavy cat the easiest solution?

This seems to be a tough, subjective question, one we haven’t been able to answer after cruising on and off for 8 years. Maybe Paul and Cheryl of Distant Shores have it figured out? The hull design of their new Orion 49 seems similar to their Southerly (1-3) in many respects.

Please share your experiences, boat model, wind conditions - good and bad.
Thank you!

One of the factors you must consider is the current where your anchored. I remember anchoring near the entrance of a bay adjacent to Johnstone Strait in British Columbia. While our stay was a pleasant one we turned 360 degrees numerous times. I later realized that the strong water flow from the adjacent strait was swirling in the location we were at. So, a number of boats on the same body of water may be affected differently dependent on the immediate current that could be very different from one location to another because of land mass particulars or strong dominant water flows nearby.

[SV Coronado]

If you're considering a catamaran, the easiest thing to do is to charter one. There are a lot of other trade-offs to cruising on a cat, both good and bad, besides their stability at anchor.

[Bowdrie]

Originally Posted by TeddyDiver

Narrow water plane area and heavy displacement works against wave action.

Yeah, you posted a good answer.
Speaking a bit tongue-in-cheek, if comfort at anchor was at the top of my list, (and I couldn't have an 85' Alden schooner like "Adventures in Paradise",) I'd be looking at a '60s vintage 12 meter.
Long, low, lean and mean, with a whole lead mine hanging underneath.

[Wandering1]

It's interesting that everybody has a different take on comfort at anchor.
To give it some perspective, we have done over 40,000nm in the last 10 years on our heavy displacement monohull. The bumpiest anchorages we have used are in the Caribbean. We often see 30kts at anchor and the large crowded anchorages mean you are often a long way down wind. This allows a sizeable chop to build up in lots of anchorages. In addition, you can often find yourself subject to a side swell creeping into the bays. A 2 foot chop and swell make for interesting conditions, and certainly influence the type of dinghy people choose when cruising the Caribbean.
Those conditions make small catamarans uncomfortable. The way action between hulls is noisy and the light weight give them a rapid bouncy motion at anchor. For this reason, we often see these catamarans getting in very close to the beach to seek more gentle conditions. That's fine, but not always possible.
Lifting keel monohulls often adopt a similar approach but with the keel up, they can occupy a large area as they swing through 180°. Not always popular in a crowded anchorage.
For the large cats and deep draught monohulls sitting it out in the bumpy part of the bay the large cats have the easiest time unless the monohull is large and heavy. Flat bottom, high windage modern monohulls that seem to be the only thing produced these days are most often the ones we see rolling and veering around their anchor. Their long waterline does see them pitching but some of the rolling we witness has to be seen to be believed. It not only modern designs of mono. We see a lot of Amels participating as well. They are a popular world cruising boat for a couple and we see many of them. Comfort at anchor is not their strong point.

[nikolay]

My boat sits pretty on her anchor being an old heavy ketch, but once I chartered a Beneteau 473 and the only way to keep her still was to ride out another anchor.

[Wandering1]

Originally Posted by barnakiel

1. a cat rather than a mono,


otherwise, if mono, then :



2. big and heavy rather than small and light,
3. beamy and flat rather than narrow and deep,


A side note - no overhangs, or at least no low lying overhangs - as these SLAM.


Another side note - rode attachment point low on the bow, NOT on the deck.


One other note - low windage, and minimal windage forward - boats with less windage sail less at anchor. Boats with more windage well aft tend to sail at lower angles.


Last but not least - a comfortable step-of-the-dink platform - e.g. boats with high topsides and no landing platform are very hard to climb onboard if you arrive when the anchorage is very choppy.


good luck, enjoy your anchorages !!!


barnakiel

I don't recognise much in there that relates to our boat and we don't roll. When every flat bottom high windage modern monohull is rolling, we are rock steady. Being a ketch, we don't veer at anchor.
We have moderate beam and we are 7'2". Round bilge and 13,000lbs of ballast in the keel, low down. Tall masts for a ketch, so some weight aloft.
The snubber attachment point is over the second bow roller, not low down. We have overhangs but not one of those slamming sugar scoops. Our hull makes no noise at anchor.
Boats with high topsides and masts well forward sail at anchor. Windage further aft keeps the boat pointing into the wind.
When the anchorage is rough, sugar scoops can be difficult to board from the dinghy since they offer no handholds. We have a vertical transom and sturdy vertical boarding ladder. We can board easily in any weather by virtue of the ladder. The same reason why pilots board ships via a ladder.
We all have different takes but it is surprising how different they can be

[barnakiel]

Yes.



Well distributed weight (plenty of ballast, low, and heavy masts) slow the roll of a mono. But slow roll is not comfort. Comfort is NO roll.


My opinions are based in spending hundreds of days anchored in (dozens?) of places. Our own boat is a 9 ft wide classic hull (and very uncomfortable), but I lived and slept on boats as different as Oysters, Amels, Catanas, Schionnings and (!) Minis. Not hundreds of data points, but dozens to be sure. I am 58 and I have started sailing when I was 4.


This is certain though that everyone will define 'comfort' in our own way. To me, comfort is NO ROLL. And also possibly no slapping slamming (which makes sleep difficult due to noise - Bavarias et Cie and no excessive sailing at anchor (which makes anchored life in the gale uneasy - boats with plenty of deck gear, biminis, davits, rolled genoas et Cie).


So this is how I defined what it takes. A cat is best, an Amel (despite their size) is very bad ...


My own boat ... forget it. But hey this is the boat I have and so I sail it as is.


Comfort at anchor is essential to those who live anchored. And otherwise boats should be designed to SAIL WELL not to ANCHOR WELL. But, we all know, we all want comfort at anchor too !!!



Cheers,
b.

[Wandering1]

Originally Posted by barnakiel

Yes.



Well distributed weight (plenty of ballast, low, and heavy masts) slow the roll of a mono. But slow roll is not comfort. Comfort is NO roll.


My opinions are based in spending hundreds of days anchored in (dozens?) of places. Our own boat is a 9 ft wide classic hull (and very uncomfortable), but I lived and slept on boats as different as Oysters, Amels, Catanas, Schionnings and (!) Minis. Not hundreds of data points, but dozens to be sure. I am 58 and I have started sailing when I was 4.


This is certain though that everyone will define 'comfort' in our own way. To me, comfort is NO ROLL. And also possibly no slapping slamming (which makes sleep difficult due to noise - Bavarias et Cie and no excessive sailing at anchor (which makes anchored life in the gale uneasy - boats with plenty of deck gear, biminis, davits, rolled genoas et Cie).


So this is how I defined what it takes. A cat is best, an Amel (despite their size) is very bad ...


My own boat ... forget it. But hey this is the boat I have and so I sail it as is.


Comfort at anchor is essential to those who live anchored. And otherwise boats should be designed to SAIL WELL not to ANCHOR WELL. But, we all know, we all want comfort at anchor too !!!



Cheers,
b.

We don't roll. We don't have slapping on the hull. 44ft long mono ketch. 13.5 foot beam. Thiis year we sailed from Antigua to Azores. 15 days. A fast trip with just me and the wife. Folding prop, vectran sails and a hull that sails well in light conditions. The main mast is as tall as the sloop version, we just have a shorter boom. You can have it all😄
Super happy with my Van de Stadt

[MicHughV]

You don't say what kind of boat you have, but I've seen Hunters, with their high topsides sail around an anchorage like crazy, and therein lies the problem.....high topsides.

I have a Bennie, which has relative low topsides by comparison and rides to an anchor steady as a rock.

So that would be my # 1 concern...ie, look for a boat with relative low topsides so as to avoid dancing the tango while anchored.

My previous two boats were also relatively low to the water and both were wonderfully docile while anchored..