CE and Sail Area

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Don Case
Posts: 53
Joined: 16 Sep 2008, 05:09

CE and Sail Area

Post by Don Case » 20 Jun 2010, 20:39

Hi
Can anyone tell me the area of the main and of the jib of an "A" rig and where(approx) the CE is? I have found 2 or 3 different formulae on the net and in books and each gives a different answer, none of which agrees with my gut feeling that this should be straight forward arithmetic that even I can follow.
Thanks
Don

PS I'm assuming that the "B" and "C" would have the same(at least horizontal) CE, am I right?
Don Case
Can 271
Vancouver Island B.C.

Frednatal
Posts: 23
Joined: 06 Aug 2009, 14:29
Sail number: BRA 66
Design: Xique-Xique
Location: Natal, RN, BRA
Contact:

Re: CE and Sail Area

Post by Frednatal » 22 Jun 2010, 00:21

Hi Don

I have some data:

A

main sail Area = 0.34679 m² CE --> XCE = -0.1215 m YCE = 0.610 m

jib sail Area = 0.2458 m² CE --> XCE = 0.1258 m YCE = 0.4760 m

Jib + Main --> Area = 0.593 m² CE --> XCE = -0.019 m YCE = 0.554 m

B

Jib + Main --> Area = 0.426 m² CE --> XCE = -0.023 m YCE = 0.412 m

C

Jib + Main --> Area = 0.272 m² CE --> XCE = -0,037 m YCE = 0.313 m

The reference for X is mast position (negative aft), for Y is the foot of sails, considering that foot are in same level.

Is not sails with total maximum permitted area.

Fred
Fred Schmidt

http://www.frediom.wordpress.com
http://www.iomdesign.worpress.com
http://footybrasil.wordpress.com/

Don Case
Posts: 53
Joined: 16 Sep 2008, 05:09

Re: CE and Sail Area

Post by Don Case » 22 Jun 2010, 22:47

Thank you Fred
It amazes me how tough it was to find this information. I would have thought it would be common knowledge. Maybe everyone was thinking," Figure it out yourself, I had to." I did roughly figure it out myself and my results are close to yours, so I'm happy.

I went and looked at your website and it looks very interesting. There doesn't happen to be an English version of the articles, does there? I tried Babelfish and it left a lot to be desired.
Thanks again
Don
Don Case
Can 271
Vancouver Island B.C.

Frednatal
Posts: 23
Joined: 06 Aug 2009, 14:29
Sail number: BRA 66
Design: Xique-Xique
Location: Natal, RN, BRA
Contact:

Re: CE and Sail Area

Post by Frednatal » 23 Jun 2010, 00:36

Hi Don

My site is exactly for this: share knowing. I can help and I am helped. It is exclusively technical. I had many difficults to learn about IOM and I do not like that peoples pass by the same.

If you have interest in some post, call me that I translate for you. If some people believe that the site has interest I can do an English version.

I have a spreadsheet that calculate the sail areas and CoG, but the Forum do not accept spreadsheets extensions, but I can send to you by e-mail

Regards

fred
Fred Schmidt

http://www.frediom.wordpress.com
http://www.iomdesign.worpress.com
http://footybrasil.wordpress.com/

Don Case
Posts: 53
Joined: 16 Sep 2008, 05:09

Re: CE and Sail Area

Post by Don Case » 23 Jun 2010, 07:05

Hi Fred
I tried a Google translation instead of Babelfish and it is much better so you needn't translate. You wouldn't have the static numbers for any other IOM's would you?
Thanks
Don
Don Case
Can 271
Vancouver Island B.C.

Frednatal
Posts: 23
Joined: 06 Aug 2009, 14:29
Sail number: BRA 66
Design: Xique-Xique
Location: Natal, RN, BRA
Contact:

Re: CE and Sail Area

Post by Frednatal » 23 Jun 2010, 15:28

Hi Don

Unhappy I do not have. Would be interesting if we could have. If someone has a table of offsets and want know resistance by Michelet, inclined waterlines, Turner's Moments, righting arm and accept make the results available for all I can do the work.

Cheers

Fred
Fred Schmidt

http://www.frediom.wordpress.com
http://www.iomdesign.worpress.com
http://footybrasil.wordpress.com/

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