What makes a sail boat offshore worthy...

[Greenman]

Obviously crew ability is paramount, as would be construction and condition of the boat. Other than that what makes the difference? I have read Island Packets and Albergs are great offshore, but how about Endeavours? Anyways, here is a comparison I found of the Island Packet 37 vs Endeavour 37 and they seem pretty close stats wise (the Endeavor actually has better stats in some key areas). Does that mean Endeavours with a good crew and in good condition will be as safe offshore?

LOA Endeavor 37 37.4

Island Packet 37 38.42

LWL Endeavor 37 30

Island Packet 37 31

Beam Endeavor 37 11.6

Island Packet 37 12.16

Disp Endeavor 37 21000

Island Packet 37 18500

Sail Area Endeavor 37 580

Island Packet 37 800

Capsize Ratio Endeavor 37 1.68 (Better)

Island Packet 37 1.84

Hull Speed Endeavor 37 7.34

Island Packet 37 7.46

Sail Area to Disp Endeavor 37 12.19 (Slower but lower knockdown risk)

Island Packet 37 18.3

Disp to LWL Endeavor 37 347 (More Comfortable in swells & more passive control tactics in weather)

Island Packet 37 277

LWL to Beam Endeavor 37 2.59

Island Packet 37 2.55

Motion Comfort Endeavor 37 38.19 (Higher is more comfortable)

Island Packet 37 30.63

Pounds/Inch Endeavor 37 1243

Island Packet 37 1347

Taken from Sail Calculator Pro v3.52 - 2000+ boats


I know there are more variables (such as the Endeavor has a modified fin and the IP is a full keel), but I was hoping for your thought on calculators such as the one at the link.

Thanks

[pogo]

Off shore worthy boats? Certainly the factors you mentioned above are a consideration, including the crew.

Equipment on board, self steering vanes, tankage for water and or fuel, epirb, HF radios, nav items, safety equipment, wind or solar generator, watermakers, proper galley and head, lee boards for the bunks, condition overall of things like standing rigging, storm sails, through hulls, etc. Many boats can be rigged for Bluewater sailing, but a good off shore boat has to be able to keep you safe and should be comfortably equipped. (Not that you couldn't do it without any of that good stuff, sort of like the Vikings.)

Pogo

[swagman]

Hi Mate,
You are right in stating crew and contruction are paramount, and to my mind the Endeavor is just as capable - maybe even more capable - for offshore passage making. The only thing the IP has going for it is a full keel and many would equally prefer that to bee a fin.
IMHO the Alberg mentioned is the best of the three. It is a sweeter looking boat. Woull sail all over the other two. Tends to have a better layout below for both offshore and livaboard. But not exactly cheap.
Cheers
JOHN

[dcstrng]

Originally Posted by Greenman

Obviously crew ability is paramount, as would be construction and condition of the boat...

For years I’ve kept an increasingly convoluted spreadsheet with most of those calculations (and a few I’ve concocted on my own… such is the plight of the arm-chair sailor) and find them an interesting way to help “see” potential performance of a boat – but I know of no “seaworthiness” calculation – witness the multihull camp, many of whose numbers seem decidedly unseaworthy, yet they travel the same oceans -- so clearly numbers are only that…

One thing the numbers don’t show (at least the superficial dimensional numbers and calculations generally derivable from the manufacturers’ spec sheets) are such basics as the strength of the rig, soundness of the hull, balance of the sail-plan and other things the skipper must inevitably deal with in real-time… I’m rereading Moitessier’s books and am again struck by the common sense of this respected (if not renowned in this techno-gizmo era… ) traveler… In his Sea Vagabond's World (the last publication before his passing) Moitessier explores many of the facets which he feels are important for a voyaging yacht – so far I’ve not found any of my favorite calculations, but tons of discussions on making reefing gear reliable, rigging durable, ground tackle reliable, ensuring good ventilation, preventing and controlling corrosion and buckets of other things…

I’m still fascinated by the various calculations – but sometimes I must laugh at myself because in the aggregate, many of these performance based numbers are a bit like asking what is the 0-60 time on an 18-wheeler… what I really want to know is how much will it carry safely, how far will it go and what are the various maintenance intervals… in any case, given the huge and varied types of boats that have made seaman like passages, I’m suspicious the dominant seaworthiness factor is the skill and common-sense of the crew… so I agree with your lead hypothesis…

[Pblais]

For years I’ve kept an increasingly convoluted spreadsheet with most of those calculations (and a few I’vie concocted on my own… such is the plight of the arm-chair sailor) and find them an interesting way to help “see” potential performance of a boat – but I know of no “seaworthiness” calculation – witness the multi hull camp, many of whose numbers seem decidedly unseaworthy, yet they travel the same oceans -- so clearly numbers are only that…

I would have to agree that the numbers are just numbers. They are what they are but they don't always mean anything. Given the dynamics involved in boating single computations always reduce the equation to the point of removing the bigger picture.

Dimensional calculations aside the two boats being compared are not equal even if the numbers want to lead you there. "Offshore" ability is a conclusion not a calculation. The term is not absolutely applied equally. Boats as small as 8 ft 9 inches have crossed the Atlantic and also the same boat went from California to Australia. Suitability is not always the same as ability.

All the above conclusions based on the numerical differences don't tell you much. A capsize ratio of one value vs another such as 1.64 vs. 1.84 does not conclude that one is better enough to conclude significant advantage. This game with numbers is abused to a great extent. You might compare them or more importantly compare a list of them for two boats but it is all too easy to exclude everything else and make conclusions that do not have meaning. You can not explain why a difference of .20 in a capsize ratio is better . The assumption is that the difference matters and if you are looking for the "better" number you assume that a small difference means more than it does.

Numbers may explain some aspects of boat but they rarely get you to a point where they allow you to assert superiority based on the numbers alone. A lot of people think they can compute the perfect boat. It's fun game. I've met two people so far that spent years computing the perfect boat and both had almost unlimited funds and then actually purchased new boats. In the end they both said the number calculations were a wasted effort.

Do number calculations lead to decisions in purchase selection? I think almost never with the exception of two numbers. The first is the right price and the second is the approval from the Admiral. If you get those two numbers right I can assure you it's a deal on a fun boat. I call it the purchase stability ratio where a value of anything other than 2.0 means the boat is going no place with you aboard.

[pogo]

Ahha! Paul, you have absolutely hit it on the head.

Pogo

[Greenman]

LOL, I knew I would get some great answers. I got the original idea of comparing boats from Beth Leonards "The Voyagers Handbook". Then started realizing some of the seeming less desirable boats had as good as stats as some of the very expensive highly recommened boats.

That got me to thinking that there may be the possibility that certain boats may be more valuable simply because of their name, kinda like designer clothes.

Anyways, thanks for the responses, I love this forum, so much great info and varied intelligent opinions.

I do agree, from what I have seen the Alberg has great lines.

Shawn

[Macopa]

Well said Paul!

[Joli]

There are many things to look at. Maybe one of the most important is how sister ships have faired when cruised for a long time. How have they handled the cyclical loading? Any broken bulkhead tabbing? Any keel movement? Any hull to deck separations? Any chain plate movement?......and on and on.

[Factor]

What makes a boat offshore worthy ------- Mainly the skipper.

Obviously there are fundamentals to consider - but the main thing is the skipper.

[bstreep]

One must also understand that original purchase prices has often determined how well a boat was THOUGHT to fair offshore. While this, many times, DOES have a correlation, it's certainly not the only correlation.

Production boats = lousy at sea has tended to be the perception in sailboats. Deserved or not.

[Alan Wheeler]

Strength of build, storage space and ability to carry the extra weight of what is stored. the rest is really as said above.

[Jim Cate]

Hi Greenman,
In my view, relying on various esoteric calculated values is a bit dangerous, but some of the basic ones do give some ideas about how the boat will perform.
You quote:
Sail Area to Disp Endeavor 37 12.19 (Slower but lower knockdown risk)

Island Packet 37 18.3

Disp to LWL Endeavor 37 347 (More Comfortable in swells & more passive control tactics in weather)

Island Packet 37 277

The extremely low sa:disp number for the Endeavor surely will indicate poor performance in light airs, and despite the tendency to concentrate on ability to survive storm conditions, most cruising is done in relatively light winds. So, if one doesn't like motoring, this is a significant factor. The sa:disp ratio, calculated with 100% sail area, has little to do with knock down risk, since in the sort of conditions which lead to knockdowns, one usually is under much reduced sail.
The very high disp:lwl number also suggests poor sailing performance, and doesn't ensure comfort in big seas. Hull shape, weight distribution, sail plan and other discretionary factors have much to do with motion in a seaway.

So, in the long run, the best way to evaluate a boats' suitability remains actually saiing on one! Often difficult to accomplish, but always worthwhile!

Good luck in your quest.

[Rollo]

Greenman,
The perfect offshore boat has never been built. In different weather and different seas characteristics change in importance. One thing is paramount a good offshore boat should keep the water on the outside. When I first started dreaming and planning to sail offshore I thought I figured out exactly what I needed and wanted. Boy am I glad I didn't have the money to buy it! Go sailing young man, take every opportunity. There are always people making passages that are looking for crew, Try different boats and learn what to do and not to do from as many people as you can.
When I started sailing you could never convince me that a boat with a open transom was a good offshore boat. When sailing out of the Golden Gate on the way to Hawaii late at night with green water coming over the bow and filling the cockpit and my boots I learned something. Two subsequent trips taught me that the faster the water gets out of the boat the better. A full cockpit is a danger and makes the boat unbalanced. Not so with a open transom. Some folks will dissagree but thats why they make different boats.
Another learned lesson. You will never get pooped from astern if your boat moves on top of the waves (and maybe as fast or slightly faster). Excessively heavy boats are not necessarily safer as they cannot get out of harms way and put great strain on sails and rigging when the seas and winds pick up.
Just pick a boat that is well built (wieght is not the big determining factor), sails well, is properly maintained and you fall in love with. In that order please!

[Maren]

Originally Posted by Pblais

...Dimensional calculations aside the two boats being compared are not equal even if the numbers want to lead you there. "Offshore" ability is a conclusion not a calculation. The term is not absolutely applied equally. Boats as small as 8 ft 9 inches have crossed the Atlantic and also the same boat went from California to Australia. Suitability is not always the same as ability...

I am in general agreement with Paul here. For a while I was trying to judge the suitability of a boat on the numbers. The problem as I came to understand it, is that the numbers seem to be the same thing but are really different classes.

Descriptive (LOA, LWL, sail area, tankage, horsepower, etc)
Derivative (hull speed for displacement boats, sail area/displacement, center of effort)
Attempt to quantify complex interaction (capsize ratio, motion comfort).

The first two classes you can’t twiddle with too much and to a small degree the same is true last class. But you can engineer for the numbers. But the problem with the last class is that’s an attempt to quantify something where perhaps not all the factors are 100% understood.

The result (in the third case) is you get a set of numbers expressed with precision, but where the accuracy is somewhat vague. But people tend to lead the same credence to all of these results when that might not be the best decision

I guess good analogy would be the first two are more akin to a newspaper article but the last is more like poetry.