13 messages2013-06-14 05:14 through 2013-07-14 23:37 UTC
Cal 39 polars
slavanaway2013-06-14 05:14
Does anyone have the poloars for the Cal 39 mark II or III?
TIA,
Sam
Re: [Cal_Boats] Cal 39 polars
Duane Knize2013-06-20 23:29 UTC
Sam,
I do for Cal 2-39 equipped with asymmetrical spinnaker.
Duane Knize
S/V Marlyn
1978 Cal 2-39 #18
On 6/13/2013 10:14 PM, slavanaway wrote:
>
> Does anyone have the poloars for the Cal 39 mark II or III?
>
> TIA,
>
> Sam
>
>
Re: [Cal_Boats] Cal 39 polars
Greg vanDalen2013-06-21 14:47 UTC
Duane,
I'd like to see that if possible.
Greg
From: Duane Knize <kn… [at] san.rr.com>
To: Ca… [at] yahoogroups.com
Sent: Thursday, June 20, 2013 4:29 PM
Subject: Re: [Cal_Boats] Cal 39 polars
Sam,
I do for Cal 2-39 equipped with asymmetrical spinnaker.
Duane Knize
S/V Marlyn
1978 Cal 2-39 #18
On 6/13/2013 10:14 PM, slavanaway wrote:
>Does anyone have the poloars for the Cal 39 mark II or III?
>
>TIA,
>
>Sam
>
>
Re: Cal 39 polars
slavanaway2013-07-10 22:10
Duane,
Would you be willing to share? My email is sa… [at] lavanway.org, I have a mark 3 (hull 154 / 1982) so it should be close if you have the standard rig and deep keel.
I have a symmetrical spinnaker but hope to get an asymmetrical as I think it would help off-wind performance instead of my 125.
I am checking into the Performance package from US Sailing too.
Thanks
Sam
--- In Ca… [at] yahoogroups.com, Duane Knize <knized@...> wrote:
>
> Sam,
>
> I do for Cal 2-39 equipped with asymmetrical spinnaker.
>
> Duane Knize
> S/V Marlyn
> 1978 Cal 2-39 #18
>
>
> On 6/13/2013 10:14 PM, slavanaway wrote:
> >
> > Does anyone have the poloars for the Cal 39 mark II or III?
> >
> > TIA,
> >
> > Sam
> >
> >
>
Cal 40 Polars
Fin Beven2013-07-10 23:22 UTC
I've attached the USSA performance package polars for a Cal-40 with the option of an asymmetrical chute.
As you can see, at 16 knots TWS, the optimum upwind speed is 6.2 knots.
Fin Beven
Radiant
Cal-40 #24
San Pedro, CA
----- Original Message -----
From: slavanaway<mailto:sa… [at] lavanaway.org>
To: Ca… [at] yahoogroups.com<mailto:Ca… [at] yahoogroups.com>
Sent: Wednesday, July 10, 2013 3:10 PM
Subject: [Cal_Boats] Re: Cal 39 polars
Duane,
Would you be willing to share? My email is sa… [at] lavanway.org<mailto:sa… [at] lavanway.org>, I have a mark 3 (hull 154 / 1982) so it should be close if you have the standard rig and deep keel.
I have a symmetrical spinnaker but hope to get an asymmetrical as I think it would help off-wind performance instead of my 125.
I am checking into the Performance package from US Sailing too.
Thanks
Sam
--- In Ca… [at] yahoogroups.com<mailto:Ca… [at] yahoogroups.com>, Duane Knize <knized@...> wrote:
>
> Sam,
>
> I do for Cal 2-39 equipped with asymmetrical spinnaker.
>
> Duane Knize
> S/V Marlyn
> 1978 Cal 2-39 #18
>
>
> On 6/13/2013 10:14 PM, slavanaway wrote:
> >
> > Does anyone have the poloars for the Cal 39 mark II or III?
> >
> > TIA,
> >
> > Sam
> >
> >
>
------------------------------------
Yahoo! Groups Links
Re: [Cal_Boats] Cal 40 Polars [1 Attachment]
Allen Edwards2013-07-11 00:23 UTC
Are these apparent wind angles?
On Wed, Jul 10, 2013 at 4:22 PM, Fin Beven <fi… [at] msn.com> wrote:
> **
>
> [Attachment(s) <#13fcae760da6f82e_TopText> from Fin Beven included below]
>
> **
> I've attached the USSA performance package polars for a Cal-40 with the
> option of an asymmetrical chute.
>
> As you can see, at 16 knots TWS, the optimum upwind speed is 6.2 knots.
>
> Fin Beven
> Radiant
> Cal-40 #24
> San Pedro, CA
>
> ----- Original Message -----
> *From:* slavanaway <sa… [at] lavanaway.org>
> *To:* Ca… [at] yahoogroups.com
> *Sent:* Wednesday, July 10, 2013 3:10 PM
> *Subject:* [Cal_Boats] Re: Cal 39 polars
>
> Duane,
>
> Would you be willing to share? My email is sa… [at] lavanway.org, I have a
> mark 3 (hull 154 / 1982) so it should be close if you have the standard rig
> and deep keel.
>
> I have a symmetrical spinnaker but hope to get an asymmetrical as I think
> it would help off-wind performance instead of my 125.
>
> I am checking into the Performance package from US Sailing too.
>
> Thanks
>
> Sam
>
>
> --- In Ca… [at] yahoogroups.com, Duane Knize <knized@...> wrote:
> >
> > Sam,
> >
> > I do for Cal 2-39 equipped with asymmetrical spinnaker.
> >
> > Duane Knize
> > S/V Marlyn
> > 1978 Cal 2-39 #18
> >
> >
> > On 6/13/2013 10:14 PM, slavanaway wrote:
> > >
> > > Does anyone have the poloars for the Cal 39 mark II or III?
> > >
> > > TIA,
> > >
> > > Sam
> > >
> > >
> >
>
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
>
>
Re: [Cal_Boats] Cal 40 Polars
Fin Beven2013-07-11 13:32 UTC
Yes, they are apparent wind angles.
----- Original Message -----
From: Allen Edwards<mailto:al… [at] gmail.com>
To: Ca… [at] yahoogroups.com<mailto:Ca… [at] yahoogroups.com>
Sent: Wednesday, July 10, 2013 5:23 PM
Subject: Re: [Cal_Boats] Cal 40 Polars
Are these apparent wind angles?
On Wed, Jul 10, 2013 at 4:22 PM, Fin Beven <fi… [at] msn.com<mailto:fi… [at] msn.com>> wrote:
[Attachment(s)<about:blank#13fcae760da6f82e_TopText> from Fin Beven included below]
I've attached the USSA performance package polars for a Cal-40 with the option of an asymmetrical chute.
As you can see, at 16 knots TWS, the optimum upwind speed is 6.2 knots.
Fin Beven
Radiant
Cal-40 #24
San Pedro, CA
----- Original Message -----
From: slavanaway<mailto:sa… [at] lavanaway.org>
To: Ca… [at] yahoogroups.com<mailto:Ca… [at] yahoogroups.com>
Sent: Wednesday, July 10, 2013 3:10 PM
Subject: [Cal_Boats] Re: Cal 39 polars
Duane,
Would you be willing to share? My email is sa… [at] lavanway.org<mailto:sa… [at] lavanway.org>, I have a mark 3 (hull 154 / 1982) so it should be close if you have the standard rig and deep keel.
I have a symmetrical spinnaker but hope to get an asymmetrical as I think it would help off-wind performance instead of my 125.
I am checking into the Performance package from US Sailing too.
Thanks
Sam
--- In Ca… [at] yahoogroups.com<mailto:Ca… [at] yahoogroups.com>, Duane Knize <knized@...> wrote:
>
> Sam,
>
> I do for Cal 2-39 equipped with asymmetrical spinnaker.
>
> Duane Knize
> S/V Marlyn
> 1978 Cal 2-39 #18
>
>
> On 6/13/2013 10:14 PM, slavanaway wrote:
> >
> > Does anyone have the poloars for the Cal 39 mark II or III?
> >
> > TIA,
> >
> > Sam
> >
> >
>
------------------------------------
Yahoo! Groups Links
Re: Cal 40 Polars
teutonprince2013-07-13 00:01
At the risk of setting in motion the "me too" bandwagon, I've been looking for polars on a 78 2-25 for quite some time without success. Would anyone know a source for these? Any help would be greatly appreciated. Thank you in advance.
R
--- In Ca… [at] yahoogroups.com, "Fin Beven" <finbeven@...> wrote:
>
> Yes, they are apparent wind angles.
> ----- Original Message -----
> From: Allen Edwards<mailto:allen.p.edwards@...>
> To: Ca… [at] yahoogroups.com<mailto:Ca… [at] yahoogroups.com>
> Sent: Wednesday, July 10, 2013 5:23 PM
> Subject: Re: [Cal_Boats] Cal 40 Polars
>
>
>
>
>
> Are these apparent wind angles?
>
>
>
> On Wed, Jul 10, 2013 at 4:22 PM, Fin Beven <finbeven@...<mailto:finbeven@...>> wrote:
>
>
> [Attachment(s)<about:blank#13fcae760da6f82e_TopText> from Fin Beven included below]
>
>
> I've attached the USSA performance package polars for a Cal-40 with the option of an asymmetrical chute.
>
> As you can see, at 16 knots TWS, the optimum upwind speed is 6.2 knots.
>
> Fin Beven
> Radiant
> Cal-40 #24
> San Pedro, CA
> ----- Original Message -----
> From: slavanaway<mailto:sam@...>
> To: Ca… [at] yahoogroups.com<mailto:Ca… [at] yahoogroups.com>
> Sent: Wednesday, July 10, 2013 3:10 PM
> Subject: [Cal_Boats] Re: Cal 39 polars
>
>
> Duane,
>
> Would you be willing to share? My email is sam@...<mailto:sam@...>, I have a mark 3 (hull 154 / 1982) so it should be close if you have the standard rig and deep keel.
>
> I have a symmetrical spinnaker but hope to get an asymmetrical as I think it would help off-wind performance instead of my 125.
>
> I am checking into the Performance package from US Sailing too.
>
> Thanks
>
> Sam
>
>
> --- In Ca… [at] yahoogroups.com<mailto:Ca… [at] yahoogroups.com>, Duane Knize <knized@> wrote:
> >
> > Sam,
> >
> > I do for Cal 2-39 equipped with asymmetrical spinnaker.
> >
> > Duane Knize
> > S/V Marlyn
> > 1978 Cal 2-39 #18
> >
> >
> > On 6/13/2013 10:14 PM, slavanaway wrote:
> > >
> > > Does anyone have the poloars for the Cal 39 mark II or III?
> > >
> > > TIA,
> > >
> > > Sam
> > >
> > >
> >
>
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
RE: [Cal_Boats] Re: Cal 40 Polars
Timm Lessley2013-07-13 00:16 UTC
Polar tables should be stated by True wind angle and True wind speed.
From: Ca… [at] yahoogroups.com [mailto:Ca… [at] yahoogroups.com] On Behalf
Of teutonprince
Sent: Friday, July 12, 2013 5:01 PM
To: Ca… [at] yahoogroups.com
Subject: [Cal_Boats] Re: Cal 40 Polars
At the risk of setting in motion the "me too" bandwagon, I've been looking
for polars on a 78 2-25 for quite some time without success. Would anyone
know a source for these? Any help would be greatly appreciated. Thank you in
advance.
R
--- In Ca… [at] yahoogroups.com <mailto:Cal_Boats%40yahoogroups.com> , "Fin
Beven" <finbeven@...> wrote:
>
> Yes, they are apparent wind angles.
> ----- Original Message -----
> From: Allen Edwards<mailto:allen.p.edwards@...>
> To: Ca… [at] yahoogroups.com <mailto:Cal_Boats%40yahoogroups.com>
<mailto:Ca… [at] yahoogroups.com <mailto:Cal_Boats%40yahoogroups.com> >
> Sent: Wednesday, July 10, 2013 5:23 PM
> Subject: Re: [Cal_Boats] Cal 40 Polars
>
>
>
>
>
> Are these apparent wind angles?
>
>
>
> On Wed, Jul 10, 2013 at 4:22 PM, Fin Beven <finbeven@...
<mailto:finbeven@...%3cmailto:finbeven@...> <mailto:finbeven@...>> wrote:
>
>
> [Attachment(s)<about:blank#13fcae760da6f82e_TopText> from Fin Beven
included below]
>
>
> I've attached the USSA performance package polars for a Cal-40 with the
option of an asymmetrical chute.
>
> As you can see, at 16 knots TWS, the optimum upwind speed is 6.2 knots.
>
> Fin Beven
> Radiant
> Cal-40 #24
> San Pedro, CA
> ----- Original Message -----
> From: slavanaway<mailto:sam@...>
> To: Ca… [at] yahoogroups.com <mailto:Cal_Boats%40yahoogroups.com>
<mailto:Ca… [at] yahoogroups.com <mailto:Cal_Boats%40yahoogroups.com> >
> Sent: Wednesday, July 10, 2013 3:10 PM
> Subject: [Cal_Boats] Re: Cal 39 polars
>
>
> Duane,
>
> Would you be willing to share? My email is sam@...
<mailto:sam@...%3cmailto:sam@> <mailto:sam@...>, I have a mark 3 (hull 154 /
1982) so it should be close if you have the standard rig and deep keel.
>
> I have a symmetrical spinnaker but hope to get an asymmetrical as I think
it would help off-wind performance instead of my 125.
>
> I am checking into the Performance package from US Sailing too.
>
> Thanks
>
> Sam
>
>
> --- In Ca… [at] yahoogroups.com <mailto:Cal_Boats%40yahoogroups.com>
<mailto:Ca… [at] yahoogroups.com <mailto:Cal_Boats%40yahoogroups.com> >,
Duane Knize <knized@> wrote:
> >
> > Sam,
> >
> > I do for Cal 2-39 equipped with asymmetrical spinnaker.
> >
> > Duane Knize
> > S/V Marlyn
> > 1978 Cal 2-39 #18
> >
> >
> > On 6/13/2013 10:14 PM, slavanaway wrote:
> > >
> > > Does anyone have the poloars for the Cal 39 mark II or III?
> > >
> > > TIA,
> > >
> > > Sam
> > >
> > >
> >
>
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
Re: [Cal_Boats] Re: Cal 40 Polars
Allen Edwards2013-07-13 01:12 UTC
I have a small collection of polars for various boats but only one Cal, the
Cal-40. I would be happy to add to the collection for others to enjoy if
anyone has more.
Here is what I have (127 polars so far)
http://L-36.com/polar_polars.php <http://l-36.com/polar_polars.php>
Allen
On Fri, Jul 12, 2013 at 5:16 PM, Timm Lessley <ti… [at] danishmarineco.com>wrote:
> **
>
>
> Polar tables should be stated by True wind angle and True wind speed.****
>
> ** **
>
> ** **
>
> ** **
>
> *From:* Ca… [at] yahoogroups.com [mailto:Ca… [at] yahoogroups.com] *On
> Behalf Of *teutonprince
> *Sent:* Friday, July 12, 2013 5:01 PM
> *To:* Ca… [at] yahoogroups.com
> *Subject:* [Cal_Boats] Re: Cal 40 Polars****
>
> ** **
>
> ****
>
> At the risk of setting in motion the "me too" bandwagon, I've been looking
> for polars on a 78 2-25 for quite some time without success. Would anyone
> know a source for these? Any help would be greatly appreciated. Thank you
> in advance.
>
> R
>
> --- In Ca… [at] yahoogroups.com, "Fin Beven" <finbeven@...> wrote:
> >
> > Yes, they are apparent wind angles.
> > ----- Original Message -----
> > From: Allen Edwards<mailto:allen.p.edwards@... <allen.p.edwards@...>>
> > To: Ca… [at] yahoogroups.com<mailto:Ca… [at] yahoogroups.com>
> > Sent: Wednesday, July 10, 2013 5:23 PM
> > Subject: Re: [Cal_Boats] Cal 40 Polars
> >
> >
> >
> >
> >
> > Are these apparent wind angles?
> >
> >
> >
> > On Wed, Jul 10, 2013 at 4:22 PM, Fin Beven <
> finbeven@...<mailto:finbeven@...>> wrote:
> >
> >
> > [Attachment(s)<about:blank#13fcae760da6f82e_TopText> from Fin Beven
> included below]
> >
> >
> > I've attached the USSA performance package polars for a Cal-40 with the
> option of an asymmetrical chute.
> >
> > As you can see, at 16 knots TWS, the optimum upwind speed is 6.2 knots.
> >
> > Fin Beven
> > Radiant
> > Cal-40 #24
> > San Pedro, CA
> > ----- Original Message -----
> > From: slavanaway<mailto:sam@... <sam@...>>
> > To: Ca… [at] yahoogroups.com<mailto:Ca… [at] yahoogroups.com>
> > Sent: Wednesday, July 10, 2013 3:10 PM
> > Subject: [Cal_Boats] Re: Cal 39 polars
> >
> >
> > Duane,
> >
> > Would you be willing to share? My email is sam@...<mailto:sam@...>, I
> have a mark 3 (hull 154 / 1982) so it should be close if you have the
> standard rig and deep keel.
> >
> > I have a symmetrical spinnaker but hope to get an asymmetrical as I
> think it would help off-wind performance instead of my 125.
> >
> > I am checking into the Performance package from US Sailing too.
> >
> > Thanks
> >
> > Sam
> >
> >
> > --- In Ca… [at] yahoogroups.com<mailto:Ca… [at] yahoogroups.com>,
> Duane Knize <knized@> wrote:
> > >
> > > Sam,
> > >
> > > I do for Cal 2-39 equipped with asymmetrical spinnaker.
> > >
> > > Duane Knize
> > > S/V Marlyn
> > > 1978 Cal 2-39 #18
> > >
> > >
> > > On 6/13/2013 10:14 PM, slavanaway wrote:
> > > >
> > > > Does anyone have the poloars for the Cal 39 mark II or III?
> > > >
> > > > TIA,
> > > >
> > > > Sam
> > > >
> > > >
> > >
> >
> >
> >
> >
> > ------------------------------------
> >
> > Yahoo! Groups Links
> >****
>
> ****
>
>
>
Re: [Cal_Boats] Re: Cal 40 Polars
John Courter2013-07-14 14:15 UTC
I'll disagree with that statement. USSail polar diagrams have true speed, true angle diagrams and true speed, relative angle diagrams. The true wind and true angle allow you to read directly off of the graph the optimum upwind and downwind angles where the curves are at a maximum and minimum. These points are transferred to the relative angle diagram so you can choose the relative wind angle to sail that your wind instruments report.
http://desiresailing.org/PolarsC&C32.pdf
From: Timm Lessley <ti… [at] danishmarineco.com>
To: Ca… [at] yahoogroups.com
Sent: Friday, July 12, 2013 5:16 PM
Subject: RE: [Cal_Boats] Re: Cal 40 Polars
Polar tables should be stated by True wind angle and True wind speed.
From:Ca… [at] yahoogroups.com [mailto:Ca… [at] yahoogroups.com] On Behalf Of teutonprince
Sent: Friday, July 12, 2013 5:01 PM
To: Ca… [at] yahoogroups.com
Subject: [Cal_Boats] Re: Cal 40 Polars
At the risk of setting in motion the "me too" bandwagon, I've been looking for polars on a 78 2-25 for quite some time without success. Would anyone know a source for these? Any help would be greatly appreciated. Thank you in advance.
R
--- In Ca… [at] yahoogroups.com, "Fin Beven" <finbeven@...> wrote:
>
> Yes, they are apparent wind angles.
> ----- Original Message -----
> From: Allen Edwards<mailto:allen.p.edwards@...>
> To: Ca… [at] yahoogroups.com<mailto:Ca… [at] yahoogroups.com>
> Sent: Wednesday, July 10, 2013 5:23 PM
> Subject: Re: [Cal_Boats] Cal 40 Polars
>
>
>
>
>
> Are these apparent wind angles?
>
>
>
> On Wed, Jul 10, 2013 at 4:22 PM, Fin Beven <finbeven@...<mailto:finbeven@...>> wrote:
>
>
> [Attachment(s)<about:blank#13fcae760da6f82e_TopText> from Fin Beven included below]
>
>
> I've attached the USSA performance package polars for a Cal-40 with the option of an asymmetrical chute.
>
> As you can see, at 16 knots TWS, the optimum upwind speed is 6.2 knots.
>
> Fin Beven
> Radiant
> Cal-40 #24
> San Pedro, CA
> ----- Original Message -----
> From: slavanaway<mailto:sam@...>
> To: Ca… [at] yahoogroups.com<mailto:Ca… [at] yahoogroups.com>
> Sent: Wednesday, July 10, 2013 3:10 PM
> Subject: [Cal_Boats] Re: Cal 39 polars
>
>
> Duane,
>
> Would you be willing to share? My email is sam@...<mailto:sam@...>, I have a mark 3 (hull 154 / 1982) so it should be close if you have the standard rig and deep keel.
>
> I have a symmetrical spinnaker but hope to get an asymmetrical as I think it would help off-wind performance instead of my 125.
>
> I am checking into the Performance package from US Sailing too.
>
> Thanks
>
> Sam
>
>
> --- In Ca… [at] yahoogroups.com<mailto:Ca… [at] yahoogroups.com>, Duane Knize <knized@> wrote:
> >
> > Sam,
> >
> > I do for Cal 2-39 equipped with asymmetrical spinnaker.
> >
> > Duane Knize
> > S/V Marlyn
> > 1978 Cal 2-39 #18
> >
> >
> > On 6/13/2013 10:14 PM, slavanaway wrote:
> > >
> > > Does anyone have the poloars for the Cal 39 mark II or III?
> > >
> > > TIA,
> > >
> > > Sam
> > >
> > >
> >
>
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
Re: [Cal_Boats] Re: Cal 40 Polars
Allen Edwards2013-07-14 15:14 UTC
All the hundred or so I have collected are given vs true wind angle. The
one posted looked like relative wind. I asked so that people would realize
that it was not in the standard form.
That said, yes a complete set might include both relative and true wind
diagrams. Of course, you can convert from one to the other. Here is a
tool that can do the math
http://L-36.com/polar_calculate.php<http://l-36.com/polar_calculate.php>,
there are several others on the web.
I always advise using boat speed rather than wind angle as a target. What
I mean by this is that changing boat speed by 1/2 a knot might only change
the apparent wind by 1 degree. Trying to stay within some fraction of a
degree of apparent wind is probably impossible but trying to stay within
something less than 1/2 a knot is doable.
Allen
On Sun, Jul 14, 2013 at 7:15 AM, John Courter <ca… [at] yahoo.com> wrote:
> **
>
>
> I'll disagree with that statement. USSail polar diagrams have true speed,
> true angle diagrams and true speed, relative angle diagrams. The true
> wind and true angle allow you to read directly off of the graph the
> optimum upwind and downwind angles where the curves are at a maximum and
> minimum. These points are transferred to the relative angle diagram so you
> can choose the relative wind angle to sail that your wind instruments
> report.
>
> http://desiresailing.org/PolarsC&C32.pdf
>
> ------------------------------
> *From:* Timm Lessley <ti… [at] danishmarineco.com>
> *To:* Ca… [at] yahoogroups.com
> *Sent:* Friday, July 12, 2013 5:16 PM
> *Subject:* RE: [Cal_Boats] Re: Cal 40 Polars
>
>
> Polar tables should be stated by True wind angle and True wind speed.
>
>
>
> *From:* Ca… [at] yahoogroups.com [mailto:Ca… [at] yahoogroups.com] *On
> Behalf Of *teutonprince
> *Sent:* Friday, July 12, 2013 5:01 PM
> *To:* Ca… [at] yahoogroups.com
> *Subject:* [Cal_Boats] Re: Cal 40 Polars
>
>
> At the risk of setting in motion the "me too" bandwagon, I've been looking
> for polars on a 78 2-25 for quite some time without success. Would anyone
> know a source for these? Any help would be greatly appreciated. Thank you
> in advance.
>
> R
>
> --- In Ca… [at] yahoogroups.com, "Fin Beven" <finbeven@...> wrote:
> >
> > Yes, they are apparent wind angles.
> > ----- Original Message -----
> > From: Allen Edwards<mailto:allen.p.edwards@... <allen.p.edwards@...>>
> > To: Ca… [at] yahoogroups.com<mailto:Ca… [at] yahoogroups.com>
> > Sent: Wednesday, July 10, 2013 5:23 PM
> > Subject: Re: [Cal_Boats] Cal 40 Polars
> >
> >
> >
> >
> >
> > Are these apparent wind angles?
> >
> >
> >
> > On Wed, Jul 10, 2013 at 4:22 PM, Fin Beven <
> finbeven@...<mailto:finbeven@...>> wrote:
> >
> >
> > [Attachment(s)<about:blank#13fcae760da6f82e_TopText> from Fin Beven
> included below]
> >
> >
> > I've attached the USSA performance package polars for a Cal-40 with the
> option of an asymmetrical chute.
> >
> > As you can see, at 16 knots TWS, the optimum upwind speed is 6.2 knots.
> >
> > Fin Beven
> > Radiant
> > Cal-40 #24
> > San Pedro, CA
> > ----- Original Message -----
> > From: slavanaway<mailto:sam@... <sam@...>>
> > To: Ca… [at] yahoogroups.com<mailto:Ca… [at] yahoogroups.com>
> > Sent: Wednesday, July 10, 2013 3:10 PM
> > Subject: [Cal_Boats] Re: Cal 39 polars
> >
> >
> > Duane,
> >
> > Would you be willing to share? My email is sam@...<mailto:sam@...>, I
> have a mark 3 (hull 154 / 1982) so it should be close if you have the
> standard rig and deep keel.
> >
> > I have a symmetrical spinnaker but hope to get an asymmetrical as I
> think it would help off-wind performance instead of my 125.
> >
> > I am checking into the Performance package from US Sailing too.
> >
> > Thanks
> >
> > Sam
> >
> >
> > --- In Ca… [at] yahoogroups.com<mailto:Ca… [at] yahoogroups.com>,
> Duane Knize <knized@> wrote:
> > >
> > > Sam,
> > >
> > > I do for Cal 2-39 equipped with asymmetrical spinnaker.
> > >
> > > Duane Knize
> > > S/V Marlyn
> > > 1978 Cal 2-39 #18
> > >
> > >
> > > On 6/13/2013 10:14 PM, slavanaway wrote:
> > > >
> > > > Does anyone have the poloars for the Cal 39 mark II or III?
> > > >
> > > > TIA,
> > > >
> > > > Sam
> > > >
> > > >
> > >
> >
> >
> >
> >
> > ------------------------------------
> >
> > Yahoo! Groups Links
> >
>
>
>
>
RE: [Cal_Boats] Re: Cal 40 Polars
Timm Lessley2013-07-14 23:37 UTC
I'll take my input from Stan -
the fastest Cal 40 on this planet.
Get Your Performance On Target
Racer's talk targets, but few understand how best to use them. Stan Honey
brings us up to speed. "From the Experts" from our April 2008 issue
by Stan Honey And Jim Teeters
related tags: Experts <http://www.sailingworld.com/experts> | Boatspeed
<http://www.sailingworld.com/expert-topics/boatspeed>
Get Your Performance On Target
C Joseph Comeau
polar plot 368
Enlarge Photo
<http://www.sailingworld.com/sites/all/files/imagecache/enlarged_image/_imag
es/200806/124-polar_plot_368.jpg>
Step aboard any well-sailed raceboat today and you're guaranteed to find
somewhere in the cockpit a laminated sheet of paper showing a spreadsheet
full of letters and numbers. For everyone directly involved with the
performance of the boat as it makes it way around a racecourse, this "Target
Table," a detailed matrix of optimum boat speeds and wind angles, is the
all-essential cheat sheet. Every boat with instruments should have one
because the information on these target sheets will guide you to your next
mark, or destination, at the optimum speed. And that is what performance
sailing is all about.
So how do we come up with these "targets" that get us around a racecourse as
quickly as possible? Well, it all starts with polars. Let's begin there, and
later get to how to use your target tables.
Polars are boatspeed predictions across a range of wind angles and wind
speeds. In its simplest form, a polar is a curved plot showing boatspeed
versus course angle to the wind (true wind angle), for a fixed wind speed.
This curved plot is called a polar because it is typically plotted using
polar coordinates. Polar coordinates are simple: you have the origin (or
center point of the plot), an angle radiating away from the plot axis, and a
distance from the origin. Angle and distance, combined, determine a unique
point on the plot.
http://www.sailingworld.com/sites/all/files/_images/201005/124-polar_plot_Ca
l_40.jpg
Joseph Comeau
The polar plot(for a Cal 40) displays the optimum sailing angles (marked
with an X) for a given true wind speed and direction.
In the first diagram, straight lines radiate from the origin at 10-degree
angles from the vertical axis, up to 180 degrees. Our polar plot assumes the
true-wind is coming straight down from the top (see wind arrow on diagram)
so all these 10-degree radiants are simply measuring the true wind angle.
There are also half circles at fixed distances from the origin; these curves
represent increasing intervals of boatspeed (in this case 0 to 10 knots).
Our diagram actually shows a family of polars for a Cal 40. The yellow
curves are our polars when sailing with a headsail; the orange polars are
used when sailing with a spinnaker. The respective curves for sailing in 10
knots of wind are bolded.
What does this polar plot tell us? And how do we apply it to our race? With
this visual it becomes very easy, and intuitive, to determine the best
sailing angles, which will get us to the next mark in the least amount of
time. Let's say you're racing to an upwind mark. Sailing upwind at any wind
angle less than 90 degrees will get you there, but only one angle will be
the fastest. If you pinch (sail too close to the wind), you'll be pointing
the boat closer to the mark, but your boatspeed will suffer as a result-the
downward curve of the polar confirms this. It will take longer to get there.
If you foot off too much, you'll certainly gain boatspeed, but at the cost
of not pointing close to where you want to go.
So the polar diagram shows us that too high is too slow and too low is too
fast. How do we use the polars find that perfect angle? In the diagram
above, we take a closer look at the upwind portion the polar chart. The
solutions for optimal upwind sailing are marked with Xs. The polar chart
makes it quite clear that this optimal point is where a horizontal line is
tangent to the polar curve. This point is the point on the curve "furthest
upwind," and it is this speed upwind that we are trying to maximize. This
upwind component is referred to as velocity made good (VMG), and sailing at
that optimal angle gives the best VMG. [For all you vector heads, this is
the vertical component of the velocity vector, drawn as an arrow from the
origin to a point on the polar curve, as we've done in the diagram.
When sailing to a leeward mark you do the same thing, using the bottom
portion of the polar curve. The interesting thing about offwind polars is
they are generally much flatter in the region of maximum VMG; if you deviate
slightly from your optimum angle, you actually lose very little of your VMG.
In other words, there is very little penalty for sailing slightly high or
low. This flatness in the curve, however, can also make it difficult to
judge your optimum offwind angles. Judging these angles is especially
difficult with lighter boats carrying lots of sail area, for which angles
can change dramatically with windspeed. Heading up a few degrees from
optimum increases apparent wind speed, increases the sail plan's driving
force, and increases boatspeed, which further increases the apparent wind,
and the boat accelerates to a new equilibrium. High-powered, lightweight
boats may easily speed up sufficiently to have a larger downwind VMG. This
is why an accurate set of polars is so valuable in maximizing your offwind
performance.
http://www.sailingworld.com/sites/all/files/_images/201005/124-polar_terms_.
jpg
How to build and use your target tables
The most valuable use of a polar plot is also the simplest, and is one
available to nearly any boat, even boats that have simple instrument
systems. This is the use of the polar files to generate a table of target
angles and speeds to sail when you're trying to maximize your VMG, upwind or
downwind. Extrapolating the data from the polar chart, I plug it into a
basic table, print the table on paper, laminate it, put self-stick Velcro on
the back, and post it where the helmsperson, main trimmer, and headsail
trimmers can all see it.
Using the target table upwind
Before you read the table, get your true wind speed by either reading TWS
from your instruments-if your instruments calculate it-or estimate the
windspeed from the sea state. Most sailors can guess TWS within a knot. Once
you know TWS, look up the "opt BS UW," and then keep that number in mind as
you race upwind. Do not use target speeds as gospel, however. Instead, use
them as a reference and keep a constant dialogue going amongst your speed
team (helm and trimmers). On a well-sailed boat you will hear such chatter
as:
Helm: "On port tack, here, we're slapping into a bit of a chop so the
targets are too tough. Let's live with two-tenths low."
Helm: "We've got a well-mixed wind here and flat water, and I'm hitting
targets too easily, let's use 0.1 fast as our number."
Trimmer: "We've got lots of right twisted wind aloft. Let's use targets that
are one-tenth slow and watch out for an increase in wind and a veer if the
twisted wind drops down to the water."
Even the grand-prix boats use their theoretical targets only as a reference,
and on any given day use target numbers that are adjusted above or below the
reference table. But once the crew picks the target for the current
conditions, they pay tons of attention to it. You'll hear lots of chatter
like:
Trimmer (coming out of a tack): "We need a half a knot more here . . . need
two-tenths more, OK we're up to speed."It's best to not change the target
table without a discussion with the trimmers and afterguard. Even if one
column is off, and you're always one-tenth low, even in perfect conditions,
the crew gets familiar with the table so you should not change it without
general agreement and awareness. On the Volvo Ocean Race, we set our target
tables two weeks after first sailing ABN AMRO One and never changed them.
They were not perfect, but everybody knew how to sail relative to them.
http://www.sailingworld.com/sites/all/files/_images/201005/124-Polar_Table_2
75.jpg
Using your downwind targets
Start by reading the TWS from your instruments, or estimate it. Using the
TWS, look up the optimum apparent wind angle (AWA). The same caveats apply
as with upwind targets: you will sometimes use a number that is higher or
lower of the target from the table, based on how the boat feels, the sea
state, and whether there's lots of wind sheer or whether the wind is well
mixed, vertically.
Whether it's better to use target true wind angle or target apparent wind
angles when sailing downwind is a religious argument for which there is no
right answer. As you can tell, I list both true wind angles and apparent
wind angles on the target table and typically set up the instrument systems
to display both so the helmsperson can use his or her preference.
Here's the basic argument: On a fast boat, as the boat surfs and the
boatspeed changes, the measured AWA will change dramatically. You don't want
the helmsperson chasing these AWA changes, so some feel that people steer
better to a TWA target on fast boats. However, if you use TWA as a target,
you also need to watch your target boatspeed (BS) to prevent an inattentive
helmsperson from sailing along at the target TWA, but too slowly and with
the AWA far too deep. This can be a stable state and the boat can stay at
target TWA, but continuously sailing far too slowly, and never accelerating
to the downwind target speed. So, when steering to target TWA, the
helmsperson needs to watch the target BS and be sure to sail hot of target
TWA until the boatspeed reaches the target BS, and then bear off to target
TWA.
The benefit of steering a target AWA is that some things work naturally. For
example, if the boat is sailing too slowly you will naturally come up to get
the AWA to the target angle, and then as the boat speeds up and the AWA
comes forward, you will naturally bear off to keep the AWA at the targets.
But, again, as the boat accelerates and decelerates on waves, the
helmsperson needs to be sure to not chase the AWA.
Different helmsmen use different approaches depending on their experience
and on the conditions. Helmsmen with strong dinghy sailing backgrounds
generally prefer AWA targets and are skilled enough sailors to naturally not
chase the AWA as the boat surfs. When conditions are very windy (and likely
dicey) downwind, many experienced sailors also like sailing to AWA because
AWA (or measured wind angle MWA) is a raw value on instrument systems that
responds quickly and is not subject to the vagaries of getting weed in the
paddlewheel or the paddlewheel coming out of the water on surfs.
_____
For more on using Polars in Offshore Races see
<http://www.sailingworld.com/from-the-experts/tactics-and-strategy/take-your
-polars-offshore-1000061206.html> "Take Your Polars Offshore"
From: Ca… [at] yahoogroups.com [mailto:Ca… [at] yahoogroups.com] On Behalf
Of Allen Edwards
Sent: Sunday, July 14, 2013 8:15 AM
To: Ca… [at] yahoogroups.com
Subject: Re: [Cal_Boats] Re: Cal 40 Polars
All the hundred or so I have collected are given vs true wind angle. The
one posted looked like relative wind. I asked so that people would realize
that it was not in the standard form.
That said, yes a complete set might include both relative and true wind
diagrams. Of course, you can convert from one to the other. Here is a tool
that can do the math http://L-36.com/polar_calculate.php, there are several
others on the web.
I always advise using boat speed rather than wind angle as a target. What I
mean by this is that changing boat speed by 1/2 a knot might only change the
apparent wind by 1 degree. Trying to stay within some fraction of a degree
of apparent wind is probably impossible but trying to stay within something
less than 1/2 a knot is doable.
Allen
On Sun, Jul 14, 2013 at 7:15 AM, John Courter <ca… [at] yahoo.com> wrote:
I'll disagree with that statement. USSail polar diagrams have true speed,
true angle diagrams and true speed, relative angle diagrams. The true wind
and true angle allow you to read directly off of the graph the optimum
upwind and downwind angles where the curves are at a maximum and minimum.
These points are transferred to the relative angle diagram so you can choose
the relative wind angle to sail that your wind instruments report.
http://desiresailing.org/PolarsC <http://desiresailing.org/PolarsC&C32.pdf>
&C32.pdf
_____
From: Timm Lessley <ti… [at] danishmarineco.com>
To: Ca… [at] yahoogroups.com
Sent: Friday, July 12, 2013 5:16 PM
Subject: RE: [Cal_Boats] Re: Cal 40 Polars
Polar tables should be stated by True wind angle and True wind speed.
From: Ca… [at] yahoogroups.com [mailto:Ca… [at] yahoogroups.com] On Behalf
Of teutonprince
Sent: Friday, July 12, 2013 5:01 PM
To: Ca… [at] yahoogroups.com
Subject: [Cal_Boats] Re: Cal 40 Polars
At the risk of setting in motion the "me too" bandwagon, I've been looking
for polars on a 78 2-25 for quite some time without success. Would anyone
know a source for these? Any help would be greatly appreciated. Thank you in
advance.
R
--- In Ca… [at] yahoogroups.com <mailto:Cal_Boats%40yahoogroups.com> , "Fin
Beven" <finbeven@...> wrote:
>
> Yes, they are apparent wind angles.
> ----- Original Message -----
> From: Allen Edwards<mailto:allen.p.edwards@...>
> To: Ca… [at] yahoogroups.com <mailto:Cal_Boats%40yahoogroups.com>
<mailto:Ca… [at] yahoogroups.com <mailto:Cal_Boats%40yahoogroups.com> >
> Sent: Wednesday, July 10, 2013 5:23 PM
> Subject: Re: [Cal_Boats] Cal 40 Polars
>
>
>
>
>
> Are these apparent wind angles?
>
>
>
> On Wed, Jul 10, 2013 at 4:22 PM, Fin Beven <finbeven@...
<mailto:finbeven@...%3cmailto:finbeven@...> <mailto:finbeven@...>> wrote:
>
>
> [Attachment(s)<about:blank#13fcae760da6f82e_TopText> from Fin Beven
included below]
>
>
> I've attached the USSA performance package polars for a Cal-40 with the
option of an asymmetrical chute.
>
> As you can see, at 16 knots TWS, the optimum upwind speed is 6.2 knots.
>
> Fin Beven
> Radiant
> Cal-40 #24
> San Pedro, CA
> ----- Original Message -----
> From: slavanaway<mailto:sam@...>
> To: Ca… [at] yahoogroups.com <mailto:Cal_Boats%40yahoogroups.com>
<mailto:Ca… [at] yahoogroups.com <mailto:Cal_Boats%40yahoogroups.com> >
> Sent: Wednesday, July 10, 2013 3:10 PM
> Subject: [Cal_Boats] Re: Cal 39 polars
>
>
> Duane,
>
> Would you be willing to share? My email is sam@...
<mailto:sam@...%3cmailto:sam@> <mailto:sam@...>, I have a mark 3 (hull 154 /
1982) so it should be close if you have the standard rig and deep keel.
>
> I have a symmetrical spinnaker but hope to get an asymmetrical as I think
it would help off-wind performance instead of my 125.
>
> I am checking into the Performance package from US Sailing too.
>
> Thanks
>
> Sam
>
>
> --- In Ca… [at] yahoogroups.com <mailto:Cal_Boats%40yahoogroups.com>
<mailto:Ca… [at] yahoogroups.com <mailto:Cal_Boats%40yahoogroups.com> >,
Duane Knize <knized@> wrote:
> >
> > Sam,
> >
> > I do for Cal 2-39 equipped with asymmetrical spinnaker.
> >
> > Duane Knize
> > S/V Marlyn
> > 1978 Cal 2-39 #18
> >
> >
> > On 6/13/2013 10:14 PM, slavanaway wrote:
> > >
> > > Does anyone have the poloars for the Cal 39 mark II or III?
> > >
> > > TIA,
> > >
> > > Sam
> > >
> > >
> >
>
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>