US Sailing
........Should have them-they were originally derived from old IOR certificates, and now that a few are racing under IMS/IRC-there should be more accurate polars available.
These are wonderful tools-but remember to achieve them you need to be in racing trim. You will not achieve polars with too much stuff on board, too much weight in the ends, nobody out on the rail (if conditions warrant), or have the wrong sail combo for the conditions (or worn out sails).
They are not cheap from US Sailing (anybody know the current cost?), so I check with a local owner who sails in the Mac and see if I can get a copy.
Cheers,
S
........Should have them-they were originally derived from old IOR certificates, and now that a few are racing under IMS/IRC-there should be more accurate polars available.
These are wonderful tools-but remember to achieve them you need to be in racing trim. You will not achieve polars with too much stuff on board, too much weight in the ends, nobody out on the rail (if conditions warrant), or have the wrong sail combo for the conditions (or worn out sails).
They are not cheap from US Sailing (anybody know the current cost?), so I check with a local owner who sails in the Mac and see if I can get a copy.
Cheers,
S
knoisewater
Member I
Reviving an old thread because I only found dead ends... I don't mind ponying up for some 35-2 polars. Anybody have any idea who I could throw my money at?
p.gazibara
Member III
I know I'm reviving an old thread, but aren't polars specific to sail set? From my understanding to truly get your boat's polars you need to go out in a variety of wind speeds and sail your boat with any/all of the sails that make sense during each particular wind condition at all points of sail. That way you can determine your boat speed and fastest sails for each angle to the wind.
That being said, once I gather enough data, I'll post Cinderella's polars. They may differ quite a bit, as I have lots of sails to choose from and my rig is out of an express 34.
On that note, does anyone know what angle of heel the 35-2 performs best at? I won't have the opportunity to take Cinderella out and get her polars before the next race series, but I know each hull has a prime heel angle to reduce wetted surface. I am reading all the books I can find on sail trim to try and get really in tune with Cinderella prior to Swiftsure.
That being said, once I gather enough data, I'll post Cinderella's polars. They may differ quite a bit, as I have lots of sails to choose from and my rig is out of an express 34.
On that note, does anyone know what angle of heel the 35-2 performs best at? I won't have the opportunity to take Cinderella out and get her polars before the next race series, but I know each hull has a prime heel angle to reduce wetted surface. I am reading all the books I can find on sail trim to try and get really in tune with Cinderella prior to Swiftsure.
I think I've seen ads that say some navigation software automatically accumulates data and generates polars for your boat over time. I don't know more about than that, however.
Except I just saw this blurb for a "black box" device that also sorta does that:
https://www.sailbits.com/blog/2017/03/yacht-devices-voyage-recorder-black-box-boat/
Except I just saw this blurb for a "black box" device that also sorta does that:
https://www.sailbits.com/blog/2017/03/yacht-devices-voyage-recorder-black-box-boat/
Real polars are very expensive to produce and were challenging to use even for the best 12-meter crews.
A notebook of successful settings amounts to the same thing and does help, or at least I thought it helped me get the best out of one-design boats.
Racing is the best way to figure this stuff out, neck and neck with similar boats over time.
That usually reveals factors much grosser than a theoretical polar does: sail selection, weather helm, angle of heel, stuff like that.
In the real world, you can get all the settings right for a particular course and conditions with a skilled helmsman and a snap-to-it crew and watch the other guy pull steadily ahead.
He ain't as good as you, you know that.
But he has new sails.
A notebook of successful settings amounts to the same thing and does help, or at least I thought it helped me get the best out of one-design boats.
Racing is the best way to figure this stuff out, neck and neck with similar boats over time.
That usually reveals factors much grosser than a theoretical polar does: sail selection, weather helm, angle of heel, stuff like that.
In the real world, you can get all the settings right for a particular course and conditions with a skilled helmsman and a snap-to-it crew and watch the other guy pull steadily ahead.
He ain't as good as you, you know that.
But he has new sails.
My first question about those data collection devices was, "How do they know what you're doing with the sails?" Unless you're always meticulous about trimming them exactly the same way. It sounds too good to be true.
Still, sometimes when I'm scratching my head, thinking "Gee, I feel like the boat should go faster than this in this kind of wind..." it would be nice if Siri would pipe up and say "Hey, Stupid! Move the jib car to position 2!"
Still, sometimes when I'm scratching my head, thinking "Gee, I feel like the boat should go faster than this in this kind of wind..." it would be nice if Siri would pipe up and say "Hey, Stupid! Move the jib car to position 2!"
p.gazibara
Member III
From the reading I have been doing, it seems like the polars are developed based on your sails and the best trim you can manage. The polars described in "Sail Power" depict the overlapping boat speed performance curves for each sail in your inventory. Granted I have not created these yet, but while I'm at it, I'll be making notes for myself. Considering I have 4 headsails and 3 spinnakers to play with, I am very interested in finding out how they perform/ max wind speeds/ wind angles for each.