I asked him if filling up the water and fuel tanks
would increase the AVS by a few degrees and if the
GZ curve provided by Tayana is correct.

1) The AVS has not been calculated for these lines,
however comparison of the areas above and below
the LPS, (Limiting angle of Positive Stability) do not
include the volume of deck erections, only the main
deck extended into centerline, because it is assumed
that they would not be watertright. Yes, if the tanks
were full, the area of negative stability would be
smaller, since their weight being low down, would
lower the center of gravity, and if the deck erections
were included it would reduce the area of negative
stability considerably.

2) The GZ curve was prepared based on the lines,
displacement at half load, and the vertical center
of gravity, the latter arrived at by the inclining
experiment. We stand by that curve showing an
LPS of a bit over 110 degrees. Once the VCG at
that loading is known the hull lines can be inclined
to any angle to determine the righting arm, negative
or positive.

He also said (over the phone) that an AVS of 110
degrees is fine for this type of boat and described
this boat as "stiff" (as Gary mentioned earlier).

wrote:
I asked him if filling up the water and fuel tanks
would increase the AVS by a few degrees and if the
GZ curve provided by Tayana is correct.

1) The AVS has not been calculated for these lines,
however comparison of the areas above and below
the LPS, (Limiting angle of Positive Stability) do not
include the volume of deck erections, only the main
deck extended into centerline, because it is assumed
that they would not be watertright. Yes, if the tanks
were full, the area of negative stability would be
smaller, since their weight being low down, would
lower the center of gravity, and if the deck erections
were included it would reduce the area of negative
stability considerably.

2) The GZ curve was prepared based on the lines,
displacement at half load, and the vertical center
of gravity, the latter arrived at by the inclining
experiment. We stand by that curve showing an
LPS of a bit over 110 degrees. Once the VCG at
that loading is known the hull lines can be inclined
to any angle to determine the righting arm, negative
or positive.

He also said (over the phone) that an AVS of 110
degrees is fine for this type of boat and described
this boat as "stiff" (as Gary mentioned earlier).
That is an interesting response. It doesn't really answer the question
of why there are two claims for AVS.

I would however, put great faith in the Vancouver 460 for two reasons;
-I think that Harris is a good proven offshore yacht designer, and
-Tayana is a proven offshore yacht builder.

Further to that, if the pilothouse is a very strong structure and the
windows can be fitted with storm covers (that are kept onboard), I would
be comfortable taking the yacht on any normal cruising route.

But then again, I like pilothouses.

Gary

Gary wrote:
That is an interesting response. It doesn't really
answer the question of why there are two claims for AVS.

I would however, put great faith in the Vancouver 460
for two reasons;
-I think that Harris is a good proven offshore yacht
designer, and
-Tayana is a proven offshore yacht builder.

Further to that, if the pilothouse is a very strong
structure and the windows can be fitted with storm
covers (that are kept onboard), I would be comfortable
taking the yacht on any normal cruising route.

But then again, I like pilothouses.

Perhaps the AVS would be 0 degree (or 180 degrees ?)
if the pilothouse is watertight. The dealer in San Diego
told me that Tayana will remove this claim from their
web site but I think they don't work on their web site
very often.

Tayana offers pilothouse storm shutters for $1575.

On Tue, 20 Dec 2005 23:26:33 GMT, Gary wrote:

-I think that Harris is a good proven offshore yacht designer, and
-Tayana is a proven offshore yacht builder.

========================================

I agree. They are quite popular among serious cruisers. I know
people who could have bought anything, and spent spent quite a bit of
time on one. Both they and the boat came back in good condition.

One way to approach this boat selection process is to go to one of the
international cruising crossroads and hang out for awhile. I'm
thinking specifically of places like Antigua, the A & BVI, and the
Bahamas. There are cruisers from all over the world in these places.
Take a look at what boats are popular and talk to people about what
they like and don't like about their boats, and their friends boats.
In several weeks, you'll learn a lot more than you will on the
internet, or from talking to boat salesmen.

wrote:
Gary wrote:

That is an interesting response. It doesn't really
answer the question of why there are two claims for AVS.

I would however, put great faith in the Vancouver 460
for two reasons;
-I think that Harris is a good proven offshore yacht
designer, and
-Tayana is a proven offshore yacht builder.

Further to that, if the pilothouse is a very strong
structure and the windows can be fitted with storm
covers (that are kept onboard), I would be comfortable
taking the yacht on any normal cruising route.

But then again, I like pilothouses.


Perhaps the AVS would be 0 degree (or 180 degrees ?)
if the pilothouse is watertight. The dealer in San Diego
told me that Tayana will remove this claim from their
web site but I think they don't work on their web site
very often.

Tayana offers pilothouse storm shutters for $1575.
That seems pricey but I haven't had any made for my boat yet. They
should be pretty skookum for $1500.

wrote:
I asked him if filling up the water and fuel tanks
would increase the AVS by a few degrees and if the
GZ curve provided by Tayana is correct.

1) The AVS has not been calculated for these lines,
however comparison of the areas above and below
the LPS, (Limiting angle of Positive Stability) do not
include the volume of deck erections, only the main
deck extended into centerline, because it is assumed
that they would not be watertright. Yes, if the tanks
were full, the area of negative stability would be
smaller, since their weight being low down, would
lower the center of gravity, and if the deck erections
were included it would reduce the area of negative
stability considerably.

2) The GZ curve was prepared based on the lines,
displacement at half load, and the vertical center
of gravity, the latter arrived at by the inclining
experiment. We stand by that curve showing an
LPS of a bit over 110 degrees. Once the VCG at
that loading is known the hull lines can be inclined
to any angle to determine the righting arm, negative
or positive.

He also said (over the phone) that an AVS of 110
degrees is fine for this type of boat and described
this boat as "stiff" (as Gary mentioned earlier).

If they don't acount for the buoyancy of the coachroof (as
some stability programs do), then a calculated LPS of 110
degrees is understandable. The coachroof/pilothouse adds a
_lot_ of buoyancy when inverted.

But you don't always go around with full tanks so don't
consider that as the best way to increase stability.

I'd feel better about the boat knowing what you do now

Evan Gatehouse