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01-02-2023, 07:49
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#31
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Registered User
Join Date: Aug 2011
Location: Chesapeake Bay/Eastern Shore
Boat: Bristol 27
Posts: 10,995
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Re: Kirsten Neuschafer Cape George 36 @ 7.9 knots
Quote:
Originally Posted by rslifkin
Dismastings would be a mixed bag there. The heavier boat will generally be more sturdy, but it also needs a bigger rig to move it, so all of the rigging is more highly loaded.
I'd be more concerned with making sure the rigging is all in perfect condition, is a bit overkill in the strength department, and that I know the boat's handling needs to avoid beating it to pieces when the going gets tough. Just having a heavy, beefy boat isn't a guarantee, although it may in some situations be more tolerant of mishandling.
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That's pretty much a given in a Round the World Race that the rigging and all associated hardware would be updated/new and possibly a size larger.
Exterior chainplates were added as well.
Mast was replaced also.
She also mentioned a heavier boat could deal with the heavier supply load for a RTW Race better than maybe a lighter boat would.
Plus she did a shakedown cruise from PEI, Canada where the refit was done to Cape Town, South Africa then sailed up to Spain then France for the race start.
So the boat was thoroughly checkout before race start.
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01-02-2023, 08:42
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#32
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Registered User
Join Date: Aug 2021
Location: PNW
Boat: 35 Ft. cutter, custom
Posts: 3,155
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Re: Kirsten Neuschafer Cape George 36 @ 7.9 knots
Quote:
Originally Posted by thomm225
She also mentioned a heavier boat could deal with the heavier supply load for a RTW Race better than maybe a lighter boat would.
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This, and it is more important than perhaps is acknowledged.
It's related to the water-plane area and pounds-per-inch immersion.
The CG hull does not change its waterplane area as much the others when weight is added, and the interface of air/water has a higher drag than water down by the keel.
Simply put, for the same weight loaded aboard, the drag from wetted surface goes up at a smaller rate on the CG.
Another factor is the "beam/length ratio" at the waterline.
The Biscay and the Rustler are short and fat compared to the CG.
At low S/L ratios that doesn't mean much, but as speed increases the induced drag rises at a faster rate, the bow wave forms earlier in the curve.
A look at the D/L ratios of the three boats shows that the WL length is more important than the weight per se.
In the "comfort factor" the CG is miles ahead, reinforcing what I said previously about crew fatigue being an important factor.
__________________
Beginning to Prepare to Commence
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01-02-2023, 08:46
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#33
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Registered User
Join Date: Mar 2021
Posts: 391
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Re: Kirsten Neuschafer Cape George 36 @ 7.9 knots
She seems to have the same self-steering than Simon Curven.
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01-02-2023, 09:50
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#34
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Registered User
Join Date: Aug 2011
Location: Chesapeake Bay/Eastern Shore
Boat: Bristol 27
Posts: 10,995
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Re: Kirsten Neuschafer Cape George 36 @ 7.9 knots
Quote:
Originally Posted by Baronkrak
She seems to have the same self-steering than Simon Curven.
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Yes, I think most all of them are using the Hydrovane
https://hydrovane.com/
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01-02-2023, 10:02
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#35
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Registered User
Join Date: Aug 2011
Location: Chesapeake Bay/Eastern Shore
Boat: Bristol 27
Posts: 10,995
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Re: Kirsten Neuschafer Cape George 36 @ 7.9 knots
Btw what is that prop on the white section to the left of the Hydrovane that evidently rotates down into the water
Power generator?
Also that boat is handling that sea very nicely
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01-02-2023, 10:20
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#37
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Registered User
Join Date: Aug 2013
Location: Back in the boat in Patagonia
Boat: Westerly Sealord
Posts: 8,544
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Re: Kirsten Neuschafer Cape George 36 @ 7.9 knots
Yes, its a Watt & Sea. Simon Kirwin's was damaged in his knockdown by the same forces that broke his Hydrovane.
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01-02-2023, 14:04
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#38
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Registered User
Join Date: Aug 2011
Location: Chesapeake Bay/Eastern Shore
Boat: Bristol 27
Posts: 10,995
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Re: Kirsten Neuschafer Cape George 36 @ 7.9 knots
Another video on her Cape George 36 refit.
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02-02-2023, 04:09
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#39
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Registered User
Join Date: Apr 2007
Location: New England/FL
Boat: Hanse 348
Posts: 1,118
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Re: Kirsten Neuschafer Cape George 36 @ 7.9 knots
Quote:
Originally Posted by thomm225
Waterline: (LWL)
Cape Georges 36: 31.5'
Rustler 36: 26.92'
Biscay 36: 27'
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I thought it was the effective lwl, that is what it is when boat is at optimal heel, not just the specified. Like boats with long overhangs on bow and stern section have a short lwl sitting at the mooring, but when sailing , they can easily get a hull speed above theoretical?
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02-02-2023, 04:52
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#40
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Registered User
Join Date: Aug 2011
Location: Chesapeake Bay/Eastern Shore
Boat: Bristol 27
Posts: 10,995
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Re: Kirsten Neuschafer Cape George 36 @ 7.9 knots
Quote:
Originally Posted by jbinbi
I thought it was the effective lwl, that is what it is when boat is at optimal heel, not just the specified. Like boats with long overhangs on bow and stern section have a short lwl sitting at the mooring, but when sailing , they can easily get a hull speed above theoretical?
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It is but the stationary (upright) LWL is a good indicator for comparison
Plus the bow on that Cape George 36 is pretty vertical as compared to a boat like mine that gets more waterline as it heals
The Cape George will get some increase in waterline but maybe not as much as other more old school traditional designs
Maybe others have a better answer though
https://sailboatdata.com/sailboat/cape-george-36
https://sailboatdata.com/sailboat/bristol-27
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02-02-2023, 09:03
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#41
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Registered User
Join Date: Aug 2021
Location: PNW
Boat: 35 Ft. cutter, custom
Posts: 3,155
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Re: Kirsten Neuschafer Cape George 36 @ 7.9 knots
For over a hundred years efforts have been made to figure out some formula or method to apply a handicap for racing purposes.
The LWL has always been at the forefront of any such effort.
The long overhangs allow a reduction in wetted surface in lighter air when there is little heeling, (or going downwind,) but lengthen the LWL when heeled, (going to weather).
The up shot is to get a better rating, (pretty much end of story, excepting aesthetics).
The shorter LWL, along with a cut-away forefoot, (and a more forward rudder mounting,) also give a faster and more responsive helm for going around the buoys and tacking.
In this race the vast majority of sailing is reaching and running and the shorter LWL has no advantage unless the wind disappears/goes light.
In the lines drawing I posted of the CG you can see that the buttock lines are similar to a section of an ellipse in shape.
The shorter LWL would have buttock lines more circular in shape.
As the S/L goes up the flatter buttock lines indicate less wave making drag, the drag going up at a lessor rate than a hull with steep buttock lines.
The additional load carrying ability and comfort are icing on the cake.
Nobody would get a CG36 to compete in PHRF for summertime around the buoys, they're meant to go to sea.
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Beginning to Prepare to Commence
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03-02-2023, 08:12
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#42
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Registered User
Join Date: Oct 2015
Location: Beaufort, NC
Posts: 742
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Re: Kirsten Neuschafer Cape George 36 @ 7.9 knots
Quote:
Originally Posted by rslifkin
The extra weight means the Cape George will be harder to push up to a point. But given enough wind, there's adequate power available to overcome that and the higher theoretical top speed from the longer waterline becomes an advantage. With a 7.5 kt hull speed, if she's doing 7.9, then there's definitely some good wind available to push that boat for pretty much all it can do.
Stuff like this is also why it's a bit hard to truly say what sailboat is faster than another. There are plenty of generalizations, ways to analyze it (such as PHRF), etc. But that all looks at the overall picture, not necessarily specific conditions. So you can easily have a "slower" boat beat a "faster" one when the conditions are right, as the slow boat may be really slow in some conditions, but decently fast in others, while the fast boat is faster in most conditions, but isn't necessarily all that fast in every possible condition.
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A possibility is at that reporting she may be in a favorable tide.
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03-02-2023, 08:18
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#43
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Registered User
Join Date: Aug 2011
Location: Chesapeake Bay/Eastern Shore
Boat: Bristol 27
Posts: 10,995
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Re: Kirsten Neuschafer Cape George 36 @ 7.9 knots
Quote:
Originally Posted by Happ
A possibility is at that reporting she may be in a favorable tide.
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Well she must have been in a favorable tide quite a bit then because she has been at that speed numerous times and as high as 8.4 knots.
8.4 knots is the highest I have found so far but I may have missed a higher one someplace.
(You can back up the tracker to check speed at various spots on the course)
Kirsten Neuschafer South Africa
Cape George 36 - 53
Speed: 8.4 knots @ 123.35°
Owner: Minnehaha
Position at: 20 Nov 2022 14:43 UTC
Lat/Lon: 39° 23.54 S, 035° 18.12 E
DTF: 8478.4 NM
Abhilash Tomy India
Rustler 36 - 71
Speed: 8.0 knots @ 106.70°
Owner: Bayanat
Position at: 23 Nov 2022 17:25 UTC
Lat/Lon: 39° 56.50 S, 044° 35.56 E
DTF: 8710.1 NM
Kirsten Neuschafer South Africa
Cape George 36 - 53
Speed: 8.0 knots @ 93.54°
Owner: Minnehaha
Position at: 05 Dec 2022 23:41 UTC
Lat/Lon: 42° 56.69 S, 084° 53.43 E
DTF: 8478.4 NM
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03-02-2023, 08:32
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#44
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Registered User
Join Date: Oct 2019
Posts: 778
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Re: Kirsten Neuschafer Cape George 36 @ 7.9 knots
She is now in the lead as Simon is heading for repairs to his wind vane in Chile. So he is out of the race and will be in the Chichester class.
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03-02-2023, 08:43
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#45
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Registered User
Join Date: Oct 2015
Location: Beaufort, NC
Posts: 742
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Re: Kirsten Neuschafer Cape George 36 @ 7.9 knots
Quote:
Originally Posted by thomm225
Well she must have been in a favorable tide quite a bit then because she has been at that speed numerous times and as high as 8.4 knots.
8.4 knots is the highest I have found so far but I may have missed a higher one someplace.
(You can back up the tracker to check speed at various spots on the course)
Kirsten Neuschafer South Africa
Cape George 36 - 53
Speed: 8.4 knots @ 123.35°
Owner: Minnehaha
Position at: 20 Nov 2022 14:43 UTC
Lat/Lon: 39° 23.54 S, 035° 18.12 E
DTF: 8478.4 NM
Abhilash Tomy India
Rustler 36 - 71
Speed: 8.0 knots @ 106.70°
Owner: Bayanat
Position at: 23 Nov 2022 17:25 UTC
Lat/Lon: 39° 56.50 S, 044° 35.56 E
DTF: 8710.1 NM
Kirsten Neuschafer South Africa
Cape George 36 - 53
Speed: 8.0 knots @ 93.54°
Owner: Minnehaha
Position at: 05 Dec 2022 23:41 UTC
Lat/Lon: 42° 56.69 S, 084° 53.43 E
DTF: 8478.4 NM
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Keep in mind tides are twice a day and 6 hours in duration.
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