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Mic
 
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Default Topic: Bluewater defined? Sailboats

In the process of researching the differences between a Grampian 26
(fin keel, spade rudder) - 4 foot draft
http://www.grampianowners.com/G26/grampian_26.html

http://sailquest.com/market/models/gramp26.htm

and a Bayfield 25 (full keel, keel hung rudder) -3 foot draft
http://sailquest.com/market/models/bayf25.htm

http://www.yachtworld.com/core/listi...5%2F27%2F05%29

http://www.sailboatlistings.com/view/2536


I came across this discussion in a forum, which may be of interest to
others. Here are some relevant excertps:


http://www.sailnet.com/messageboards...=1&Topic=11194

Topic: Bluewater defined?

Date: Jan. 31 2005 8:21 PM
Author: Jeff_H )
It is hard to answer your question specifically. To a great extent
this is a question of definition. Much of this is rather long
discussion is exerpted from early discussions on the topic of what
makes an offshore capable vessel;

As I have noted in prior discussions, the term 'bluewater capable'
seems to get bandied about as if it had some kind of fixed meaning
that can be measured on some absolute scale. To some, this term seems
to mean that the boat is safe to take on an offshore passage, while to
others it seems to imply an ability to distance cruise to remote
locations. This range of interpretations would imply a broad spectrum
containing very different kinds of boats.

Most well constructed coastal cruisers are perfectly seaworthy for a
carefully timed offshore passage. What they often lack is the kind of
layout and design details that make offshore passages comfortable.

Where coastal cruisers fail as long distance offshore cruising boats
is in the ability to withstand the large amount of wear and tear that
long distance cruisers incur in a very short period of time. As I have
noted before in these discussions, a heavily used coastal cruiser
might sail something on the order of 1000 miles in a year with most
boats sailing considerably less than that. A boat being used for
distance voyaging can often sail well in excess of 10,000 miles in a
year, with much of that passagemaking in the harsh environment of the
tropics.

There is often a tendancy to focus on such items as the AVS (angle of
vanishing stability, which by the way I personally prefer the older,
more widely accepted, and more linguistically accurate term LPS- limit
of positive stability)or STIX (CE Stability Index) as key elements of
the overall safety of a boat offshore.

These numbers represent a very small snapshot of the real safety of a
boat and as such can be grossly misleading. An extremely high AVS or
STIX can be easily achieved simply by designing an excessively narrow
boat with lots of freeboard, but with that excessively narrow beam and
high tophamper, comes a greatly increased likelihood of a capsize or
roll over and a deterioration in motion comfort and carrying capacity.

In following the research process that resulted in STIX, it should be
understood that the purpose in developing the CE Directive for
Recreational Watercraft, of which STIX is a component, was never to
extablish an absolute standard for vessels going offshore. Instead it
was intended to develop a minimum and easily quantifiable standard
that all of the CE countries could agree upon. In doing so, key
calculations and measurements were omitted from the standards because
member nations considered them to be onerous. Instead simplified
surrogate formulas were substituted for actual more sophisticated
calculations resulting in very loose and sometimes missleading
approximations. This is especially unfortunate since there was
adequate detailed research to have permitted very accurate stability
assessments to made.

AVS suffers from another problem as well. As has been pointed out many
times on this forum, there is no uniform standard for calculating AVS.
It is not unusual to see very high AVS figures quoted in ads, but they
mean little in an absolute sense because of the wide range of methods
used to calculate a boat's AVS. Some published angles are for boats in
their most advantageous loadings (full water tanks and empty lockers)
while other are at their worst (IMS calcs with empty tanks, and which
do not include the volume of the cabin). None of these numbers take
into account the weight distribution and buoyancy of the vessel in the
inverted condition which can greatly alter the relative stability of
individual vessels as the approach their limits of positive stability.

When I think of a coastal cruiser vs. a dedicated offshore boat, there
are a number attributes that I look for:

-Accommodations:
On a coastal cruiser there should be good wide berths, with enough
seaberths for at least half of the crew for that night run back to
make it to work the next day. An offshore cruiser is often handled by
a smaller crew and so fewer berths and fewer seaberths are necessary.
The berths on an offshore boat should be narrower and have leeboards
or lee cloths to keep the crew in place on either tack. On both types
I would look for a well-equipped galley but the galley needs to be
larger on a coastal cruiser so that there is adequate space to prepare
meals for a larger crew or a raft-up. For coastal cruising large
un-interupted counter tops are great for preparing elegant spreads and
are easier to keep clean, but for offshore use can result in flying
food. Deep sturdy fiddles that divide the counter into smaller
segments work better for offshore cruising. Refrigeration is less
important on a coastal cruiser although the case can be made for no
refrigeration or icebox if you are going distance voyaging offshore.
Large open cabin soles make coastal cruisers seem air and roomy, but
offshore provide little foothold for crew moving around a heeled and
bucking cabin.

-Cockpit:
A comfortable cockpit for lounging is very important on a coastal
cruiser. It should be larger than an offshore boat to accommodate a
larger number of people, which is OK since pooping is less likely to
occur doing coastal work.

-Deck hardwa
While gear for offshore boats need to be simple and very robust,
coastal cruisers need to be able to quickly adapt to changing
conditions. Greater purchase, lower friction hardware, easy to reach
cockpit-lead control lines, all make for quicker and easier
adjustments to the changes in wind speed and angle that occur with
greater frequency. There is a big difference in the gear needed when
‘we’ll tack tomorrow or the next day vs. auto-tacking or short tacking
up a creek.

-Displacement:
Offshore boats need to be heavier. They carry more stuff, period. The
traditional rule of thumb was that an offshore boat needs to weigh
somewhere between 2 1/2 (5400 lbs) and 5 long tons (11,000) per
person. A coastal cruiser can get by with less weight per crew person
but generally is cruised by a larger crew. The problem that I have
with most selection processes is that most offshore sailors and many
coastal cruisers seem to start out looking for a certain length boat
and then screen out the boats that are lighter than the displacement
that they think that they need. This results in offshore boats and
some coastal cruisers that are generally comparatively heavy for their
length. There is a big price paid in motion comfort, difficulty of
handling, performance and seaworthiness when too much weight is
crammed into a short sailing length.

I suggest that a better way to go is to start with the displacement
that makes sense for your needs and then look for a longer boat with
that displacement. That will generally result in a boat that is more
seaworthy, easier on the crew to sail, have a more comfortable motion,
have a greater carrying capacity, have more room on board, and be
faster as well. Since purchase, and maintenance costs are generally
proportional to the displacement of the boat the longer boat of the
same displacement will often have similar maintenance costs. Since
sail area is displacement and drag dependent, the longer boat of an
equal displacement will often have an easier to handle sail plan as
well.

It is important to understand that in and of itself, weight does
nothing good for a boat. Weight does not add strength. It does not
make for a more comfortable motion. It does not add stability. It does
not make for greater carrying capacity. Weight only breeds more
weight. Adding weight begins a design cycle that can make a boat
harder to handle and more expensive to build with few if any
improvements to the boat itself. To explain, as a boat becomes heavier
drag increases. As drag increases the sail plan needs to get larger.
With increased sail area, there is a greater need for stability. To
gain that greater stability, ballast weight and drag increases which
starts the another cycle of weight increases. With greater sail area
and stability, hull structure needs to get heavier, and, rigging and
spar sizes need to increase, and with that greater weight comes the
need for still more sail area and stability. With the greater weight
aloft comes greater roll angles, a reduction in AVS and an increased
likelihood of capsize or knockdown. When the cycles stops, the larger
sail plans of a heavier displacement boat makes them harder to handle
and that weight increase is in places that do not add to weight
carrying capacity. Weight does nothing good for a boat!
-Keel and Rudder types:
I would say unequivocally that for coastal cruising a fin keel is the
right way to go here. The greater speed, lesser leeway, higher
stability and ability to stand to an efficient sail plan, greater
maneuverability and superior windward performance of a fin keel with
spade rudder (either skeg or post hung) are invaluable for coastal
work. Besides fin keels/bulb keels are much easier to un-stick in a
grounding. In shallower venues a daggerboard with a bulb or a
keel/centerboard is also a good way to go.

There is a less obvious choice when it comes to the keel and rudder
type for offshore cruising. Many people prefer long or full keels for
offshore work but to a great extent this is an anachronistic thinking
that emerges from recollections of early fin-keelers. Properly
engineered and designed, a fin keel can be a better choice for
offshore work. Here though is the rub. Few fin keelers in the size and
price range that most people are considering are engineered and
designed for dedicated offshore cruising.

Full or long keels offer quite a few advantages when cruising off of
the beaten path, such as the ability to safely dry out on a remote
beach or haul out on an old style marine railway.

-Ground tackle:
Good ground tackle and rode-handling gear is important for both types
but all-chain rodes and massive hurricane proof anchors are not
generally required for coastal cruising.

-Sailplan:
At least along the US East Coast, (where I sail and so am most
familiar with) light air performance and the ability to change gears
is important for a coastal cruiser. It means more sailing time vs.
motoring time and the ability to adjust to the 'if you don't like the
weather, wait a minute' which is typical of East Coast or Great Lakes
sailing. If you are going to gunkhole under sail, maneuverability is
important. Windward and off wind performance is also important.

With all of that in mind I would suggest that a fractional sloop rig
with a generous standing sail plan, non- or minimally overlapping
jibs, and an easy to use backstay adjuster is ideal for a coastal
cruiser. This combination is easy to tack and trim and change gears
on. I would want two-line slab reefing for quick, on the fly, reefing.
I would want an easy to deploy spinnaker as well.

More and more designers of offshore crusiers are turning to fractional
rigs for distance cruisers as well. This switch seems to be especially
popular in Europe rather in the States where the cutter rig still
seems to the default answer for long distance voyaging.

-Speed:
I think that speed is especially important to coastal cruising. To me
speed relates to range and range relates to more diverse
opportunities. To explain, with speed comes a greater range that is
comfortable to sail in a given day. In the sailing venues that I have
typically sailed in, being able to sail farther in a day means a lot
more places that can be reached under sail without flogging the crew
or running the engine. When coastal cruising speed also relates to
being able to duck in somewhere when things get dicey.

It is harder to make the case for the need for speed in an offshore or
distance cruiser. Speed can be an asset to an offshore cruiser. More
speed means fewer days at sea and less motoring time. That results in
a greater range without restocking and so a reduced need for tankage
and the need carry less supplies. Argueably greater speed allows an
offshore vessel to strategically deal with weather patterns, which
when coupled with better weather forecasting information can be a real
safety advantage. That said, it is rare that even a very fast boat can
'out run a hurricane'.

-Ventilation:
Good ventilation is very critical to both types. Operable ports,
hatches, dorades are very important. While offshore, small openings
are structurally a good idea, for coastal work this is less of an
issue.

-Visibility and a comfortable helm station:
Coastal boats are more likely to be hand steered in the more
frequently changing conditions, and higher traffic found in coastal
cruising and are more likely to have greater traffic to deal with as
well. A comfortable helm position and good visibility is critical.
Offshore, protection of the crew becomes more important.

Storage and Tankage:
There is a perception that coastal cruisers do not need as much
storage. I disagree with that. Coastal cruisers need different kinds
of storage than an offshore boat but not necessarily less storage.
Good storage is needed to accommodate the larger crowds that are more
likely to cruise on a short trip. Good water and holding tankage is
important because people use water more liberally inshore assuming a
nearby fill up, and with a larger crew this takes a toll quickly.
Holding tanks are not needed offshore but they are being inspected
with greater frequency in crowded inshore harbors and there are few
things worse than cruising with a full holding tank and no way to
empty it. Offshore boats generally need larger and segregated fuel
tanks with fuel scrubbing capabilities. Offshore vessels can tolerate
more less convenient long term storage areas.

Respectfully
Jeff

Date: Feb. 02 2005 10:24 AM
Author: PCP

(snip)

Those categories are defined by parameters regarding the minimum
safety characteristics a boat has to have, regarding uses in different
sea conditions. From the Directive:

“Definitions:

A. OCEAN: Designed for extended voyages where conditions may exceed
wind force 8 (Beaufort scale) and significant wave heights of 4 m and
above, and vessels largely self-sufficient.
B. OFFSHO Designed for offshore voyages where conditions up to, and
including, wind force 8 and significant wave heights up to, and
including, 4 m may be experienced.
C. INSHO Designed for voyages in coastal waters, large bays,
estuaries, lakes and rivers where conditions up to, and including,
wind force 6 and significant wave heights up to, and including, 2 m
may be experienced.
D. SHELTERED WATERS: Designed for voyages on small lakes, rivers, and
canals where conditions up to, and including, wind force 4 and
significant wave heights up to, and including, 0,5 m may be
experienced.”

” Boats in each Category must be designed and constructed to withstand
these parameters in respect of stability, buoyancy, and other relevant
essential requirements listed in Annex I, and have good handling
characteristics.”

So category Class A means unrestricted ocean going boat.

Date: Jan. 31 2005 4:24 AM
Author: GordMay
In the final analysis, the capabilities of a boat (bluewater, coastal,
inland, etc) are determined by the master (& crew) - and second
guessed by everyone else.

STIX Categories:

“A” (Unlimited Ocean) STIX Value 32 - adequate to withstand up to a
force 10 gale, with average waves of 7 m height and eventual wave
heights of 14 m.

“B” (Offshore) STIX Value 23 - adequate to withstand up to force 8
winds, with average waves of 4 m.

“C” (Coastal) STIX Value 14 - adequate to withstand up to force 6
winds , with average waves of 2 m.

“D” (Local) STIX Value 5 - adequate to withstand up to force 4 winds,
with waves of 0.5 m maximum.

References:
http://www.rorc.org/programme/stix.php
http://www.yachting-world.com/yw/sta...tability97.pdf
http://rorcrating.com/stix/stixpaper.pdf

FWIW,
Gord
XXXXXXXXXXXXX

Other link: What Makes a Safe Offshore Boat
http://www.sailnet.com/collections/c...ising%20Styles


XXXXXXXXXXXXXXXX

production boats vs blue water cruisiers

http://www.cruisersforum.com/showthr... threadid=1630

http://www.cruisersforum.com/showthr...5&pagenumber=2
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OMG, CE certification for "Bluewater capable". Whats next, euronannies
telling us that it is illegal for a non-CE certified boat to go more
than 3 miles offshore?
Is it true that people in europe actually have to be licensed to have a
sailboat?

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DSK
 
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Mic wrote:
In the process of researching the differences between a Grampian 26
and a Bayfield 25


They're quite different boats. The Grampian 26 is a fairly typical
racer-cruiser of her era, the Bayfield 25 is crab-crusher.

As for the long winded discussion about "blue water capable," much of it
is hogwash, much of the rest is pablum intended to soothe the people who
want a rational reason to buy a crab-crusher. If you want one, and can
afford it, buy one! Don't prattle about how much yarrer it is.



Date: Jan. 31 2005 8:21 PM
Author: Jeff_H )

"... following the research process that resulted in STIX, it should be
understood that the purpose in developing the CE Directive for
Recreational Watercraft, of which STIX is a component, was never to
extablish an absolute standard for vessels going offshore."


Partly because it is impossible to quantify the destructive power which
the sea might or might not unleash upon a cruising sailboat at any given
time; but the biggest factor is that the skipper's knowledge & skill is
the overwhelmingly biggest factor in the seaworthiness of any vessel.


(more from Jeff) "... Instead it
was intended to develop a minimum and easily quantifiable standard
that all of the CE countries could agree upon. In doing so, key
calculations and measurements were omitted from the standards because
member nations considered them to be onerous."


And also because the builders did not want to be muzzled by strict
engineering standards about how strongly boats must be built. Please
notice that those damned awful racing sailors aren't so squeamish, and
have put some rather demanding math into their required safety standards
for the big offshore races.

In short, if a crab-crusher can't pass a test that a VOC racer can, why
in heck would anybody in their right mind claim the crab-crusher was
more seaworthy or more "blue-water capable"? Yet you see this done all
the time.


I think some of these comments must have been written a long time ago

"When I think of a coastal cruiser vs. a dedicated offshore boat, there
are a number attributes that I look for:

-Cockpit:
A comfortable cockpit for lounging is very important on a coastal
cruiser. It should be larger than an offshore boat to accommodate a
larger number of people, which is OK since pooping is less likely to
occur doing coastal work.


Actually this is doubly false. Waves closer to shore are likely to be
steeper & breaking, weather is likely to change more quickly, and
lastly, the relation of cockpit size to the danger of getting pooped
should be viewed thru the perspective of reserve bouyancy in the aft
hull sections. A boat with a tiny cockpit (such as found in all the
old-timey crab crushers) and very little reserve bouyancy is greater
danger, especially if she has small cockpit drains. An open transom is
the best way to clear the cockpit, it can't clog or sink the boat via a
failed thru-hull. Yet many 'blue-water sailors' condemn open transoms as
unseaworthy. In fact, one once told me that our open transom boat (a
small trailerable which made no pretense of being a passagemaker) was
death trap.



-Deck hardwa
While gear for offshore boats need to be simple and very robust,
coastal cruisers need to be able to quickly adapt to changing
conditions. Greater purchase, lower friction hardware, easy to reach
cockpit-lead control lines, all make for quicker and easier
adjustments


Uh huh. And so a 'blue-water' craft should have high friction hardware
and unreachable control lines? Once again, the racers lead the way here.
Boats have been sailed *hard* all the way around the world, with an
array of low-friction blocks, crew-friendly cockpit layouts, roller
furlers, self-tailing winches, and all the rest intended to make the rig
easy to handle.



"... There is a big difference in the gear needed when
‘we’ll tack tomorrow or the next day vs. auto-tacking or short tacking
up a creek."


I disagree strongly. A boat that is unhandy is stays, has a large slow
turning radius, and a rig that is difficult to handle, is in danger any
time she is close to shore or another vessel.


-Displacement:
Offshore boats need to be heavier.


Not really.

... They carry more stuff, period.


Why can't a light boat with good reserve bouyancy "carry more stuff"? In
fact, the whole issue of added weight is related more to reserve
bouyancy than initial (unloaded) displacement.

Now here's some good advice:

"I suggest that a better way to go is to start with the displacement
that makes sense for your needs and then look for a longer boat with
that displacement. That will generally result in a boat that is more
seaworthy, easier on the crew to sail, have a more comfortable motion,
have a greater carrying capacity, have more room on board, and be
faster as well."


Agreed with the exception of more comfortable motion. The motion may or
may not be noticably less comfortable, but increasing length for a given
disp necessarily lowers the L/D ratio which results in a bouncier ride.

" .... Since purchase, and maintenance costs are generally
proportional to the displacement of the boat the longer boat of the
same displacement will often have similar maintenance costs."


Agreed somewhat. Complexity is really what drives up maintenance costs.
Less gear & simpler gear, and thorough technical knowledge on the part
of the crew, is the way to reduce maintenance time & costs... remember,
cruising is defined as 'fixing your boat in exotic & inconvenient
locations' so the more time you spend on maintenance, the less time
cruising.



"It is important to understand that in and of itself, weight does
nothing good for a boat."


Hear hear.

Uffa Fox once said, "The only vehicle which benefits from added weight
is a steam roller."

... Weight does not add strength. It does not
make for a more comfortable motion.


I disagree on this last. It does, but it's probably not the prime factor
in differing 'motion comfort' between boats of similar D/L.



-Ventilation:
Good ventilation is very critical to both types.


You bet it is, and so are good screens. Lack of *useable* ventilation,
or ventilation that spits water, will result in a swampy dank cabin in
which it is impossible to be comfortable. And swarms of bugs will also
render the cabin very unpleasant.

Frankly, I think the term "blue water cruiser" is a marketing gimmick.
Capable skippers can & have circumnavigated in unlikely vessels such as
a shoal draft oyster sloop ballasted with loose rocks (Slocum's SPRAY,
of course) or Indian war canoes rigged for sail. The way to have a
seaworthy boat is to learn how to sail as thoroughly as you can. Then
you'll have your opinions about what boat is best, and what's more,
you'll know how to get the best out of her.

Fresh Breezes- Doug King

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Frank
 
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Well, I was gonna prepare a lengthy reply; but... What Doug said!



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DSK
 
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Frank wrote:
Well, I was gonna prepare a lengthy reply; but... What Doug said!


Don't hold back, I got my asbestos suit (and tinfoil beanie) on

DSK

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