Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 24-04-2008, 13:32   #61
Registered User

Join Date: Nov 2005
Location: Ohio
Posts: 2,313
All these issues go away if the builders simply post polars like Fastcat does. I asked some questions above so am looking forward to Gideons responses.

Quote:
Originally Posted by Nordic cat View Post
Thanks for the update Dave.

When I compare your speeds to my FP Tobago, then they are only marginally better. I must say that I expected at least 30-50% higher speeds.
The Tobago will do 10 knots at 37 degrees with a TWS of 19-20 knots with mainsail (38 m2) and non standard self tacking jib (16m2). This is at a weight of just under 5 tons. Tacking angles of 90 degrees only in very flat water. (So 5-8 degrees of drift at 20 knots)
I do not consider the Tobago as being a fast boat, but it is probably above the median for the production cats.

With a 10-12 ft longer waterline, and slimmer hulls (I think), I had higher expectations of the Catanas performance. The better pointing ability is clear to see against fixed keels.

They are very nice boats, but I'm even more impressed with the marketing about how fast they are. It seems they achieve this without directly stating speeds.

Then this is perpetuated by all the brokers and boat testers like in the article posted earlier.

Gideon stated in another thread that he had a friend with a Catana, maybe he can get some polars, or help with some factual feedback??

Regards

Alan
__________________

__________________
Joli is offline   Reply With Quote
Old 24-04-2008, 14:36   #62
Registered User

Join Date: Apr 2008
Location: istanbul
Boat: think to buy Catana 431
Posts: 29
Quote:
Originally Posted by fastcat435 View Post
The Dean 440 , the Moorings 46 , Nautitech 47 , Lagoon 440, and a few other where out there and there was only 10 knots of wind and we had 8 people on board and still made 8 knots !!!
Hi Gideon, you always come with the wind nice to meet you dear commercial vendor

I want to ask you something that I confuse

Is the sailing area and displacement everything for you?
If I increase my 40 feet catana's sailing area up to 1000 m2 with 100 meter mast what will happen?

How much secure is driving fast over 12-15 knots with some catamaran like kite??? or how many minute feel yourself good at this speeg on this kite?
__________________

__________________
mamo is offline   Reply With Quote
Old 25-04-2008, 01:39   #63
Marine Service Provider
 
fastcat435's Avatar

Cruisers Forum Supporter

Join Date: Jul 2007
Location: Amstelveen Netherlands
Boat: FastCat 445 Green Motion
Posts: 1,649
Images: 10
Send a message via Skype™ to fastcat435
Quote:
Originally Posted by mamo View Post
Hi Gideon, you always come with the wind nice to meet you dear commercial vendor

I want to ask you something that I confuse

Is the sailing area and displacement everything for you?
If I increase my 40 feet catana's sailing area up to 1000 m2 with 100 meter mast what will happen?

How much secure is driving fast over 12-15 knots with some catamaran like kite??? or how many minute feel yourself good at this speeg on this kite?
Morning Mamo

No sail area and speed is not everything , it needs to be accompanied with safety , comfort , space and a good feel otherwise why go thru all the trouble of trying to make the perfect sailing catamaran.
sailing at 12 thru 17 knots is safe and secure over 17 one has to be alert all the time and this is very dependent on wave conditions.I do not think that you need an answer to your question as it speeks for itself.
The main items that are very important in order to get a perfomance yacht and this works for multihulls and monohulls even
displacement versus sail area .
Take a 10 ton yacht and give it 50 squire meters of sail area and you will have a very slow boat, take a 5 ton boat and give it 100 meters of sail area and now you have a performance yacht.
Weight is drag and sail area is power.
Empty out a lagoon 440 keeping al tank near empty etc and she will be reasonable fast.
Take a Catana 431 with the empty weight of 9 tons and load her up to her max allowed weight of 12 tons and she will be a slow cat.
I have never seen a polar of any Catana but I hava sailed the 401 , 431 , 471 472 and 521 and all did not impress me , they where all faster than the average cat of simular sizes but the claims where always that these cats where very fast and they are not. The 472 and 521 where outright dissappointing in performance.
They are all good cats , well constructed and reasonable comfortable but not fast.

Greetings
Gideon
__________________
fastcat435 is offline   Reply With Quote
Old 25-04-2008, 01:51   #64
Marine Service Provider
 
fastcat435's Avatar

Cruisers Forum Supporter

Join Date: Jul 2007
Location: Amstelveen Netherlands
Boat: FastCat 445 Green Motion
Posts: 1,649
Images: 10
Send a message via Skype™ to fastcat435
Quote:
Originally Posted by Joli View Post
Hello Gideon,

Glad you are here. I'll break my word and ask a couple questions, you are very knowledgable and quite helpful.

Your polars.

Oops, posted to fast.

1) Are the polars tws and twa, tws and awa, or aws and awa?
2) Do you sail to a target awa and target speed or do you sail to a target vmg?
3) Can you post tabulated VMG versus wind speed and load. Up and down?

You are one of the few who make polars readily available. Good job!

Joli

Hallo Joli
1.these polars are all with TWS and TWA
2. sailing is done to a target VMG
3. the VMG s are marked in the polars with small blocks rear the higher wind angles.
All these polars are made as if you are on virtually flat water so wave action slows a boat down unless the waves come from behind .

Greetings

Gideon
__________________
fastcat435 is offline   Reply With Quote
Old 25-04-2008, 06:58   #65
Marine Service Provider

Join Date: Mar 2007
Location: Ft Lauderdale, FL
Posts: 80
Leopard 46' in La Rochelle?

p.s. at the La Rochelle boat show 2 years ago we circled around all the other cats sailing out there with exception of the Black Rider
Brest Rider Construction, a catamaran running faster than the wind
a carbon fiber racing performance cat of 40 ft without accomodations and they beat us but just.
The Dean 440 , the Moorings 46 , Nautitech 47 , Lagoon 440, and a few other where out there and there was only 10 knots of wind and we had 8 people on board and still made 8 knots !!!


Dear Gideon,

My name is Peter Wiersema, I am one of the sales agents for Leopard catamarans in the United States.

Correction to your statement: The Leopard 46' was never exhibited at the La Rochelle boatshow !

Below is the polar of the Gino Morelli designed Leopard 46'. The light air performance is phenomenal, there are various Leopard 46' owners on this board who can confirm this. The modern hull design with flared topsides gives little wet area and increased interior space.

After having build close to 80 hulls for the Leopard 46' already (50% for private owner and 50% for charter activities), it is a proven concept.

The delivery crews are not allowed to do more than 220M p/day in order to avoid any wear and tear on the boat, and the average delivery is 39 days at sea from Capetown to Ft Lauderdale.

kind regards,
Peter

pwiersema@leopardcatamarans.com
Attached Thumbnails
Click image for larger version

Name:	Leopard 46 2007 Polar speed -wind.JPG
Views:	1105
Size:	52.2 KB
ID:	3427  
__________________
catabroker is offline   Reply With Quote
Old 25-04-2008, 07:15   #66
Senior Cruiser
 
schoonerdog's Avatar

Cruisers Forum Supporter

Join Date: May 2004
Location: annapolis
Boat: st francis 44 mk II catamaran
Posts: 1,174
Images: 4
[quote=mamo;155667]


If you're looking for a less expensive (and less posh) boat which gets good performance:

St Francis 44 7.7t Displacement LD, 115 SQM sail area (65 MS, 50 Genoa), SA/LD 14.935. Consider you could replace the glass in the settee area with margard lexan, replace the mast with a carbon fiber everything, get the fancy valence technology LiSu light weight batteries, and cut around 1000 lbs total in the process moving the SA/DL to 15.97, replace every piece of electronics with the best of the best, refurbish every single stitch of material with ultrasuede and still be saving 200-300k from the cost of a new boat of comperable size and now have an extremely fast circumnavigator and for all practical comforts a new boat. It's a good bargain.
__________________
schoonerdog is offline   Reply With Quote
Old 25-04-2008, 07:32   #67
Marine Service Provider
 
fastcat435's Avatar

Cruisers Forum Supporter

Join Date: Jul 2007
Location: Amstelveen Netherlands
Boat: FastCat 445 Green Motion
Posts: 1,649
Images: 10
Send a message via Skype™ to fastcat435
Hallo Peter
Which Robertson and Caine was at the La Rochelle boat show in 2006 ?
The 46 sails better than the predecessor but it still is an actual cruising ( charter ) catamaran as your polar indicates .
If I compare polars between the FastCat 455 and the Leopard 46 cats in the same size and waterline lenght

with 20 knots of wind at 90 degrees angle the Leopard according to the polar will do 14 knots while the 455 will do better than 16 or a 15 % difference in speed
with 10 knots of wind speed the 46 is slightly below 8 knots while the 455 is over 8 knots
I have taken the 8000 kilo polar or heavy loaded with 3000 kilo for an
ocean crossing , there is no indication what the loading condition of the Leopard is but I presume that it is light loaded , if different let us know the load in this polar please.
When looking at a lightly loaded 455 the differences become huge

Warm Greetings

Gideon
Attached Thumbnails
Click image for larger version

Name:	435 winddiagr. 8000 kg.JPG
Views:	380
Size:	87.0 KB
ID:	3432  
__________________
fastcat435 is offline   Reply With Quote
Old 25-04-2008, 07:39   #68
Registered User

Join Date: Nov 2005
Location: Ohio
Posts: 2,313
Quote:
Originally Posted by fastcat435 View Post
Hallo Joli
1.these polars are all with TWS and TWA
2. sailing is done to a target VMG
3. the VMG s are marked in the polars with small blocks rear the higher wind angles.
All these polars are made as if you are on virtually flat water so wave action slows a boat down unless the waves come from behind .

Greetings

Gideon
Hello Gideon,

Very good looking polars for sure. It might be good to identify they are tws and twa. I understand the numbers are based on flat water and prudence is required when sailing in higher winds. Upwind at 17 with tws of 25 gives 40 over the deck and probably a good size sea to deal with, I would guess you would need to back down or something is going to break.

We always sailed to a target VMG with an eye on tws/aws. That is why I was asking what the polars represented.

It would be nice to see polars from everyone but if performance is to be hidden that is probably not going to happen.

Thank you for responding, as always well done.

Joli
__________________
Joli is offline   Reply With Quote
Old 25-04-2008, 07:44   #69
Marine Service Provider
 
fastcat435's Avatar

Cruisers Forum Supporter

Join Date: Jul 2007
Location: Amstelveen Netherlands
Boat: FastCat 445 Green Motion
Posts: 1,649
Images: 10
Send a message via Skype™ to fastcat435
Quote:
Originally Posted by Joli View Post
Hello Gideon,

Very good looking polars for sure. It might be good to identify they are tws and twa. I understand the numbers are based on flat water and prudence is required when sailing in higher winds. Upwind at 17 with tws of 25 gives 40 over the deck and probably a good size sea to deal with, I would guess you would need to back down or something is going to break.

We always sailed to a target VMG with an eye on tws/aws. That is why I was asking what the polars represented.

It would be nice to see polars from everyone but if performance is to be hidden that is probably not going to happen.

Thank you for responding, as always well done.

Joli
Hallo Joli

Polars mean nothing if the corresponding weights are not present
Just look at the difference between 5500 kilo and 8000 kilo and this is for the original prototype , we have improved on these polars but are not done yet.
Once Green Motion is perfected I expect to improve with up to 10 % in all speeds and be able to get on or close to wind speed up to 20 knots
We are still getting resistance and weight down .

I have attached our target polar but we have not reached this yet

Greetings

Gideon
Attached Files
File Type: pdf 0271p 45.pdf (15.0 KB, 148 views)
__________________
fastcat435 is offline   Reply With Quote
Old 25-04-2008, 08:05   #70
Senior Cruiser
 
schoonerdog's Avatar

Cruisers Forum Supporter

Join Date: May 2004
Location: annapolis
Boat: st francis 44 mk II catamaran
Posts: 1,174
Images: 4
Peter,

Looking quickly, the Leapord would then have specs of 12 tons light displacement (24,206lbs), 134 SQM sail area and a SA/LD of around 11.16 putting everything in the same reference as the other boats Mamo had published. Would that be accurate?



Quote:
Originally Posted by catabroker View Post
p.s. at the La Rochelle boat show 2 years ago we circled around all the other cats sailing out there with exception of the Black Rider
Brest Rider Construction, a catamaran running faster than the wind
a carbon fiber racing performance cat of 40 ft without accomodations and they beat us but just.
The Dean 440 , the Moorings 46 , Nautitech 47 , Lagoon 440, and a few other where out there and there was only 10 knots of wind and we had 8 people on board and still made 8 knots !!!


Dear Gideon,

My name is Peter Wiersema, I am one of the sales agents for Leopard catamarans in the United States.

Correction to your statement: The Leopard 46' was never exhibited at the La Rochelle boatshow !

Below is the polar of the Gino Morelli designed Leopard 46'. The light air performance is phenomenal, there are various Leopard 46' owners on this board who can confirm this. The modern hull design with flared topsides gives little wet area and increased interior space.

After having build close to 80 hulls for the Leopard 46' already (50% for private owner and 50% for charter activities), it is a proven concept.

The delivery crews are not allowed to do more than 220M p/day in order to avoid any wear and tear on the boat, and the average delivery is 39 days at sea from Capetown to Ft Lauderdale.

kind regards,
Peter

pwiersema@leopardcatamarans.com
__________________
schoonerdog is offline   Reply With Quote
Old 25-04-2008, 08:17   #71
Registered User
 
Nordic cat's Avatar

Join Date: Jan 2008
Location: Denmark
Boat: FP Tobago 35
Posts: 721
Dear Gideon,

My name is Peter Wiersema, I am one of the sales agents for Leopard catamarans in the United States.

Correction to your statement: The Leopard 46' was never exhibited at the La Rochelle boatshow !

Below is the polar of the Gino Morelli designed Leopard 46'. The light air performance is phenomenal, there are various Leopard 46' owners on this board who can confirm this. The modern hull design with flared topsides gives little wet area and increased interior space.
kind regards,
Peter

pwiersema@leopardcatamarans.com[/quote]

Hi Peter,

You are correct,

It was a Leopard 40, called Umbulala. See photo below which I took.

I take it that your polars are in knots, for both wind and boatspeed?

Looks like she isn't to good to windward, as the polars stop at around 45 degrees, is this correct?

Some load figures, as well as verification of the polars would be great. Are these the polars based on some VPP or actually measured?

Thanks for posting them.

Regards

Alan
Attached Thumbnails
Click image for larger version

Name:	IMGP0471.JPG
Views:	193
Size:	324.9 KB
ID:	3435  
__________________
Nordic cat is offline   Reply With Quote
Old 25-04-2008, 08:28   #72
Senior Cruiser
 
schoonerdog's Avatar

Cruisers Forum Supporter

Join Date: May 2004
Location: annapolis
Boat: st francis 44 mk II catamaran
Posts: 1,174
Images: 4
Mamo, I for one think your looking at precisely the right thing. Hull profiles, extruding shelves underneath, etc can (and do) affect the performance, but were I looking at specs to get a quick and dirty idea of how boats performed, you are looking at exactly the right thing. Trying to then take anecdotal evidence of so and so made such and such time on a passage is really inaccurate as they have often blown out sails, had inexperienced crew, etc. My VW TDI can make it to NYC in the same amount of time as a ferrari, but I don't think it's as fast! Also polars have such fudge factors put in in terms of hull smoothness, surface waves, etc and frankly when people actually sail the boats they often find that they aren't doing what the polars predicted. No reason to overwork the problem, SA/LD is a great general measure of boat performance.


Quote:
Originally Posted by mamo View Post



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..
__________________
schoonerdog is offline   Reply With Quote
Old 25-04-2008, 09:12   #73
Registered User

Join Date: Nov 2005
Location: Ohio
Posts: 2,313
Hello Gideon,

I understand. As the weight goes on the speed goes away and it is more pronounced with a multi then a mono (ie sinking narrow hulls). If you build a heavy cat and then add a payload of one ton per person there is no speed. Certainly you have gone to expectional degrees to achieve light weight thus maintaining speed. Gunboat does the same but most others don't. Possibly that is why polars are so hard to come by. Marketing the illusion of speed is easier when hard facts are not available.

Honestly I wonder if some multis have the ability to sail to weather if the breeze is over 35. The windage of the superstructure is so large that the reefed sails cannot over come the resitance. Not the place I want to be if trapped on a lee shore.

Joli


Quote:
Originally Posted by fastcat435 View Post
Hallo Joli

Polars mean nothing if the corresponding weights are not present
Just look at the difference between 5500 kilo and 8000 kilo and this is for the original prototype , we have improved on these polars but are not done yet.
Once Green Motion is perfected I expect to improve with up to 10 % in all speeds and be able to get on or close to wind speed up to 20 knots
We are still getting resistance and weight down .

I have attached our target polar but we have not reached this yet

Greetings

Gideon
__________________
Joli is offline   Reply With Quote
Old 25-04-2008, 10:02   #74
Moderator Emeritus
 
David M's Avatar

Cruisers Forum Supporter

Join Date: Sep 2007
Location: San Francisco Bay
Boat: research vessel
Posts: 10,152
Just to let everyone know. Catana never bothered writing me back. I requested some polars for their boats.

In the past, I have written to Gunboat with some questions and they wrote me back. I have written to AfricanCats and they wrote me back.

If you want to sell boats Catana, then you need to respond to your potential customers.

David
__________________
David

Life begins where land ends.
David M is offline   Reply With Quote
Old 25-04-2008, 10:29   #75
Moderator Emeritus
 
David M's Avatar

Cruisers Forum Supporter

Join Date: Sep 2007
Location: San Francisco Bay
Boat: research vessel
Posts: 10,152
Quote:
Originally Posted by Joli View Post
Hello Gideon,

I understand. As the weight goes on the speed goes away and it is more pronounced with a multi then a mono (ie sinking narrow hulls). If you build a heavy cat and then add a payload of one ton per person there is no speed. Certainly you have gone to expectional degrees to achieve light weight thus maintaining speed. Gunboat does the same but most others don't. Possibly that is why polars are so hard to come by. Marketing the illusion of speed is easier when hard facts are not available.

Honestly I wonder if some multis have the ability to sail to weather if the breeze is over 35. The windage of the superstructure is so large that the reefed sails cannot over come the resitance. Not the place I want to be if trapped on a lee shore.
Joli
I used to do it quite frequently on my Hobie 18 on the San Francisco Bay. Of course I did not have a cabin with vertical forward windows and a flying bridge like a Lagoon, but I did it. Besides, once in the tropics, how often do you need to beat to weather for days on end?

Wouldn't your engines come into play if you could not make any headway against a lee shore?
__________________

__________________
David

Life begins where land ends.
David M is offline   Reply With Quote
Reply

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Centerboard Performance zippy Monohull Sailboats 14 06-03-2012 05:15
90s Catanas and Delamination? Jordan Multihull Sailboats 1 06-02-2010 08:37
New 41ft and 46ft Catanas Coming capezio11 Multihull Sailboats 13 22-08-2008 14:46
Board Performance TaoJones Forum Tech Support & Site Help 3 26-09-2007 21:29
Catanas?? Lightfin Multihull Sailboats 13 24-01-2006 11:39



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 13:57.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.