IRC Rating - Spinnaker size

harstonwood

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Boat is rated at 0.997, with biggest Assymetric spinnaker 92 sq M.
It would be good for us if we could get the rating down to 0.990 so we can score in a different class.
Whilst we don't particularly want to reduce sail size, we predominantly race offshore and wondered how much smaller would the A2 have to be to achieve this
I think we are stuck with the higher rating but any thoughts?
(boat is sunfast 3200)
 
Boat is rated at 0.997, with biggest Assymetric spinnaker 92 sq M.
It would be good for us if we could get the rating down to 0.990 so we can score in a different class.
Whilst we don't particularly want to reduce sail size, we predominantly race offshore and wondered how much smaller would the A2 have to be to achieve this
I think we are stuck with the higher rating but any thoughts?
(boat is sunfast 3200)

I almost certainly wouldn't reduce the kite area. I'd look at reduced Jib luff length and possibly a shorter foot main. Should be able to get 7 points with some pretty minor changes I'd have thought.
 
Boat is rated at 0.997, with biggest Assymetric spinnaker 92 sq M.
It would be good for us if we could get the rating down to 0.990 so we can score in a different class.
Whilst we don't particularly want to reduce sail size, we predominantly race offshore and wondered how much smaller would the A2 have to be to achieve this
I think we are stuck with the higher rating but any thoughts?
(boat is sunfast 3200)


Just bear in mind that there is a reason that the mk2 SF3200's have a much bigger mast and sail area than originally specified for the mk1 design and why pretty much all the original SunFast 3200's now have oversized mainsails / jibs / spinnakers compared to the original specification, because the boat is incredibly sticky in light airs without the larger sails. So if you are sure that all of your races will be in 8 knots of breeze or over then go for it, but if you do have any light airs races you will probably have to accept that you will come last in them as opposed to with the larger sail plan you still stand a chance of being at least mid fleet ( I did win one light airs coastal race in the three seasons I had the 3200 but it really isn't their forte no matter what you do).
 
Just bear in mind that there is a reason that the mk2 SF3200's have a much bigger mast and sail area than originally specified for the mk1 design and why pretty much all the original SunFast 3200's now have oversized mainsails / jibs / spinnakers compared to the original specification, because the boat is incredibly sticky in light airs without the larger sails. So if you are sure that all of your races will be in 8 knots of breeze or over then go for it, but if you do have any light airs races you will probably have to accept that you will come last in them as opposed to with the larger sail plan you still stand a chance of being at least mid fleet ( I did win one light airs coastal race in the three seasons I had the 3200 but it really isn't their forte no matter what you do).

Different calculation though when you're talking about dropping rating to be the scratch boat in the fleet below.

It is a shame that he's ruled out the shorter jib hoist though, as that does seem to be a way to get quite a few points saved off without losing any especially useful sail area. I'd also think about having the boat weighed if I hadn't already done that. Often good for a few points. And then just check all the dimensions, have the largest jib re-measured. It's probably shrunk so might be a point there. Ditto the kite. 7 points isn't huge and can probably be done without major surgery....
 
Just bear in mind that there is a reason that the mk2 SF3200's have a much bigger mast and sail area than originally specified for the mk1 design and why pretty much all the original SunFast 3200's now have oversized mainsails / jibs / spinnakers compared to the original specification, because the boat is incredibly sticky in light airs without the larger sails. So if you are sure that all of your races will be in 8 knots of breeze or over then go for it, but if you do have any light airs races you will probably have to accept that you will come last in them as opposed to with the larger sail plan you still stand a chance of being at least mid fleet ( I did win one light airs coastal race in the three seasons I had the 3200 but it really isn't their forte no matter what you do).

All good points. It’s generally breezy in the Irish Sea. Will have to have a think. No rush to do anything.
 
Different calculation though when you're talking about dropping rating to be the scratch boat in the fleet below.

It is a shame that he's ruled out the shorter jib hoist though, as that does seem to be a way to get quite a few points saved off without losing any especially useful sail area. I'd also think about having the boat weighed if I hadn't already done that. Often good for a few points. And then just check all the dimensions, have the largest jib re-measured. It's probably shrunk so might be a point there. Ditto the kite. 7 points isn't huge and can probably be done without major surgery....

Will be doing a full weigh/measure next year
Funnily enough I have measured the Jibs, and they are shorter than the data on the irc certificate
I do take note of your comments flaming, and am very grateful for them.
 
8th of June was a Friday and Sunday wa the 10th
Two ISORA races to and from the IOM. Plenty of breeze later on the Sunday, Friday a bit lighter. But I take your point!

8th July in fact. Those that say I don't know what day it is might be right.

We did about 18 miles in 10 hours total, about 1-2Kn for the first 4 hours about 3Kn in the next two hours, we ground to a complete halt in the end.
 
In reply to the original question, to get 7 points out of the spinnakers it would be need 28sqm taking out approx...

As others have pointed out the boat is sticky in the light so you don't want to reduce too much sail area.

You could do it but you would want to look at getting the points from all over the boat, re-weigh (possibly add a battery or two to help), work on your overhangs, some out of main P and E, little out of Jib LL and maybee a slightly shorter sprit.
 
In reply to the original question, to get 7 points out of the spinnakers it would be need 28sqm taking out approx...

As others have pointed out the boat is sticky in the light so you don't want to reduce too much sail area.

Weighing next month and measure the sails, and then take it from there! Certainly don’t want to reduce the sail area by that much!

You could do it but you would want to look at getting the points from all over the boat, re-weigh (possibly add a battery or two to help), work on your overhangs, some out of main P and E, little out of Jib LL and maybee a slightly shorter sprit.
 
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