Study for Sail Area / Displacement Ratio of some cats

mamo · 24-04-2008, 05:47

This is my study on Sail Area / Displacement ratio of some cats which I think to buy..I can add more parameters or cats if you wish and please correct me if I have any mistake on this table.. I am waiting your comments

mamo · 24-04-2008, 06:13

These are my opinions;

- Logoon look heavy and slow than the others

- 420 hybrid is like a joke, standingbull

- Mahe looks good performer at the first sight but slow down dramatically with loading

- most important up to me; Catanas catch the myth of Fastcat by loading

- and lavezzi 40 looks good almost as much as catanas and fastcat

- my favorite is catana 431 and 471

2Hulls · 24-04-2008, 06:35

mamo - a correction on the 471 stats - main is ~80m2.

And don't believe that weight. Don't believe the weights from any cat manufacturer.

Dave

mamo · 24-04-2008, 06:44

Dave, maybe you have short mast version

88 m2 mainsail is true.

mamo · 24-04-2008, 06:50

and I also understood something after studying this table;
why fastcats can't go to join ARC

terhohalme · 24-04-2008, 08:16

Mamo,

Good work, but you should use this formula for sail area displacement ratio:

SDR = SA/D^0.667

Then the ratios are comparable to values in literature. Displacement is cubic and sail area is squared, this is why the exponent should be 2/3 (= 0.667).

Terho

Robertcateran · 24-04-2008, 22:27

Good Point Terho,
Where does your proa fit?
Robert

terhohalme · 25-04-2008, 05:16

I sold him (yes proa is he) to a new proanaut (she).

BigCat · 26-04-2008, 15:50

No need to do all that math: This online calculator will do it for you. Of course, to believe the result you have to believe the displacement figure..........

SA / D Ratio

Maren · 26-04-2008, 16:59

Quote:

Originally Posted by terhohalme

I sold him (yes proa is he) to a new proanaut (she).

OOOh. Lucky she is. The force is strong with her

Sorry I was just having a hard time understanding your sentence. It looked like Yoda-speak.

Maren · 26-04-2008, 17:02

Quote:

Originally Posted by mamo

I take it the numbers in bold are to indicate a fastcat/catana471 performance turning point?

mamo · 26-04-2008, 17:05

Quote:

Originally Posted by BigCat

No need to do all that math:

NO NEED THE COMMERCIAL VENDORS ALSO

mamo · 26-04-2008, 17:08

Quote:

Originally Posted by Maren

I take it the numbers in bold are to indicate a fastcat/catana471 performance turning point?

YESS.. PERFORMANS COMES TO SAME POİNT BY PAYLOAD.. BUT I PREPARE NEW AND MORE DETAILED TABLE..I LL SEND IT SOON..

BigCat · 26-04-2008, 17:23

Quote:

Originally Posted by mamo

NO NEED THE COMMERCIAL VENDORS ALSO

I think I have just been complained about, but I'm not sure-are you objecting to my posting a useful link to a third party's website? If so, why?

If it is terhohalme's remarks that irked you, he is quite right, you know-that is how yacht designers do it.

And Maren, I'd say that terhohalme's English is much, much better than our Finnish-way better than mine, anyway.

24-04-2008, 05:45	#1
mamo Registered User Join Date: Apr 2008 Location: istanbul Boat: think to buy Catana 431 Posts: 29	Study for Sail Area / Displacement Ratio of some cats

26-04-2008, 15:50	#10
BigCat cruiser Join Date: May 2007 Location: Seattle area Boat: Building 65' catamaran Posts: 765	Sail area displacement calculator No need to do all that math: This online calculator will do it for you. Of course, to believe the result you have to believe the displacement figure.......... SA / D Ratio

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24-04-2008, 05:47	#2
mamo Registered User Join Date: Apr 2008 Location: istanbul Boat: think to buy Catana 431 Posts: 29	This is my study on Sail Area / Displacement ratio of some cats which I think to buy..I can add more parameters or cats if you wish and please correct me if I have any mistake on this table.. I am waiting your comments

24-04-2008, 06:13	#3
mamo Registered User Join Date: Apr 2008 Location: istanbul Boat: think to buy Catana 431 Posts: 29	These are my opinions; - Logoon look heavy and slow than the others - 420 hybrid is like a joke, standingbull - Mahe looks good performer at the first sight but slow down dramatically with loading - most important up to me; Catanas catch the myth of Fastcat by loading - and lavezzi 40 looks good almost as much as catanas and fastcat - my favorite is catana 431 and 471

24-04-2008, 06:35	#4
2Hulls Registered User Join Date: Oct 2007 Location: Chesapeake Bay Boat: Catana 471 Posts: 311	mamo - a correction on the 471 stats - main is ~80m2. And don't believe that weight. Don't believe the weights from any cat manufacturer. Dave

24-04-2008, 06:44	#5
mamo Registered User Join Date: Apr 2008 Location: istanbul Boat: think to buy Catana 431 Posts: 29	Dave, maybe you have short mast version 88 m2 mainsail is true.

24-04-2008, 06:50	#6
mamo Registered User Join Date: Apr 2008 Location: istanbul Boat: think to buy Catana 431 Posts: 29	and I also understood something after studying this table; why fastcats can't go to join ARC

24-04-2008, 08:16	#7
terhohalme Registered User Join Date: Jan 2008 Location: Finland Boat: Catharsis 27 under construction Posts: 31 Images: 1	Mamo, Good work, but you should use this formula for sail area displacement ratio: SDR = SA/D^0.667 Then the ratios are comparable to values in literature. Displacement is cubic and sail area is squared, this is why the exponent should be 2/3 (= 0.667). Terho

24-04-2008, 22:27	#8
Robertcateran Registered User Join Date: Feb 2008 Location: Oz Boat: Jarcat 5, 5m, Mandy Posts: 419	Good Point Terho, Where does your proa fit? Robert

25-04-2008, 05:16	#9
terhohalme Registered User Join Date: Jan 2008 Location: Finland Boat: Catharsis 27 under construction Posts: 31 Images: 1	I sold him (yes proa is he) to a new proanaut (she).