Motion Comfort

[sailorboy1]

Another ratio thing that only really works well in comparing boats of same type, size, and design. It doesn't carryover well between the designs that were being done back when Ted Brewer came up it and newer hull shapes.

My current Hunter 410 has a lower comfort ratio and lower displcement/length ratio than my last Cal-39. But since the water line on the Hunter doesn't change much under way if you used underway sailing waterline to the ratios the story becomes a lot different.

On the other hand for a given size of boat I feel it safe to say that the higher displacement the more comfortable the ride will be.........once you get it moving! But once the sht hits the fan and it gets really rough it isn't going to made much difference as you toss your cookies on either.

[s/v Beth]

Originally Posted by Randyonr3

If and falling to be uncomfortable, you change directions to sail in the trough and the comfort changes..
It seems that the comfort motion of the boat has as much to do with the person opperating it as much as the type of boat it is..

I would say that both contribute, with an exceptional sailor able to overcome the deficencies of a boat and visa versa. I used to charter big bendies, then Island Packets. In the Valient I found a boat that made up for my bluewater deficencies....
That said, I would venture to say you aare a better sailor.

[topfish]

Originally Posted by Bash

Yeah, it goes up with boat size.

So we needed Ted Brewer to tell us that larger boats tend to be more comfy than smaller boats?

The numbers can be confusing- The Flicka, Dana and Norsea have lowere numbers yet are considered very comfortable in heavy sea.

Here is a link about Ted Brewer and the numbers..

CRUNCHING NUMBERS: Brewer Comfort Ratio

here is one quote worth thought! "It isn’t really possible to quantify all aspects of a boat’s motion in a single numerical parameter. But there is a relatively simple so-called “comfort ratio,” developed by designer Ted Brewer, that does provide a reasonable indication of what a boat’s motion will be like in certain conditions. "

The link was a good read and was very informative for me! Hope others enjoy!

[denverd0n]

Originally Posted by Target9000

Also comfort is arguably subjective.

I don't see how anyone could argue that point. Comfort is totally subjective, and totally individual.

If you are comfortable on your boat then it has all the "comfort rating" it needs.

[zeehag]

ratios are not necessarily the definition of comfort. i love how folks follow anything that is written 0online as gods word. lol is hilarious.
comfort comes in so many definitions as to bve ridiculously difficult to accurately define in words much less numbers.
comfort is SUBJECTIVE, and , as such, is limited to within one's own ability to determine. individually or in pairs or however you travel.

i personally prefer the ride of a deep draft, deep full-keeled ketch.

[David_Old_Jersey]

All boats can be f#ggin uncomfortable at times - my "measurement" revolves around difficulty in making a cup of tea

[zeehag]

doj--i like htat measurement--perfect!!!

[VirtualVagabond]

Originally Posted by zeehag

doj--i like htat measurement--perfect!!!

Nah... that's a useless measure... It's perfect with coffee...

[boatman61]

Originally Posted by VirtualVagabond

Nah... that's a useless measure... It's perfect with coffee...

+A1.....
Stuff that wishy washy Brit dishwater.... lol

[zeehag]

Originally Posted by boatman61

+A1.....
Stuff that wishy washy Brit dishwater.... lol

coffee, tea,,,,,,the only difference is that coffee tastes better unless you are sick, then tea with honey and lemon and BOOZE.....

oh yeah, and mocha my way aint made with tea....LOL

[hummingway]

My beam of 14 feet gives the size ratio a multiplier of about 33.5. At 12 it would only be about 27. 70% of 32.5 LW gives 22.75 while 30% of 41.5 is 12.45 added together 35.2.

At 14 feet the formula has a divisor of 766.48 where 12 feet gives 617.76.

It isn't clear to me if it's total displacement but I presume it is and mine is in the neighbor hood of 38,000 all in. 14 feet gives 49.5 whereas 12 feet gives 61.5 which with a 14 foot beam would need over 47000 pounds.

I'm sure in either case David could make his drink of choice.

A 60 foot boot with a 45 foot LW with the same beam and displacement as mine comes up about 35 from a divisor of 1077. It would need to displace 53354 to get the same number.

So really I think the formula is saying, increase volume of the boat and, for comfort, increase the displacement. Bigger boats aren't necessarily going to give better motion.

[Large Luke]

I ran across a chart a while back that may help you figure out motion comfort, and compare your boat to 2499 others out there. It also has some other interesting numbers for you to check out. Go to Sail Calculator Pro v3.53 - 2500+ boats and your days of doing math to find this answer are over! I hope this helps.

[svHannabel]

Biggest comfort ratio given in the list on page 1 of this thread: Colin Archer 37 Pilot Cutter, Motion Comfort=54.67

That's a big number for a 37 footer! Anyone come up with the most UN-comfortable 37 footer?

[bangkaboat]

I thought that everybody knew that motion comfort was the single most important measurement for sailboats, because it makes us "classic plastic" sailors feel much more brave about taking on the newer Hunter/ Catalina crowd!

Oh sure, you may have a boat that, aesthetically, looks like a lear jet, in comparison to mine resembling a C-130 cargo plane &, yes, you may be a "bit" faster, but while I'm smoothly sailing the bounding main, you're coughing up your cookies & preparing to abandon ship!

All of this being said, of course, as I sit here in Ensenada because "The Admiral" - I finally "get" this term, oh man do I get it - doesn't feel that tomorrow is "the right time" to head south and the weekend, when the wind will likely drop to single digits "seems better". All I know is that, if I move the boat before The Admiral is ready, my berth won't be moving for a very long time.

While I bow to the opinions of the designers, veteran cruisers & delivery captains, I really don't think that one can give much creedence to this measurement(except, as I said, when talking to owners of newer Hunters & Catalinas)