Fastest with equal sail

[Slowmo]

Do you know of 2 (or more) boat types that have about the same standard sail area?

Analyzing and learning. It would be very interesting to look upon some different boats with aproximately the same sail area.

which hull is fastest, most seaworthy and why?


I don't know much, but I hope you do.

[Dutch Peter]

Originally Posted by Slowmo

Do you know of 2 (or more) boat types that have about the same standard sail area?

Better look on the web for that, there are too many to list here.

Originally Posted by Slowmo

Analyzing and learning. It would be very interesting to look upon some different boats with aproximately the same sail area.

which hull is fastest, most seaworthy and why?

That's been done, you just have to know where to find the reports!

But, go on, ask!!

[Slowmo]

Originally Posted by Dutch Peter

Better look on the web for that, there are too many to list here.

That's been done, you just have to know where to find the reports!

Please, take two examples. Well known types is probably most giving. That's something to start with.

If we allways should read "everything" first, befor debating.... there wouldn't hardly be any debate at all, would it?

[Dutch Peter]

Two examples for you:

Catalina 30 MK III
L = 9,15 m
Lwl = 7,62 m
B = 3,3 m
Sail area =40,6 m^2
Weight = 4,7 tonnes

J-92
L = 9,2 m
Lwl = 7,93 m
B = 3,05 m
Sail area = 41,9 m^2
Weight = 2,5 tonnes

So, my educated guess is the J-92 is faster because:
Length of waterline is longer
Breadth is smaller
Ship is lighter

[Slowmo]

Hmmm. Naturally. When comparing two modells, with more or less the same design simple mathmatics gives the answer.

From start I had a txt line saying "dinghies" around 10-20m2. Why? I naturally mean to compare more simple designs. They can look very different.

Comparing computer designs of the same consepts is not much point since it's hard even to recognise the differences for a non trained eye.
If I remember right some of the OS-classes are boats that origin from dark cellars ages ago.... which makes them interesting.

[Dutch Peter]

Slowmo,

That's the second time you get back on an answer in a way I don't like!
What's the problem? You don't like the answer, then change the question!
You seam to know so much about the subjects your asking about, come up with 2 designs on your own, and we'll debat about those!


Dutch Peter

[Slowmo]

Originally Posted by Dutch Peter

Slowmo,

That's the second time you get back on an answer in a way I don't like!
What's the problem? You don't like the answer, then change the question!
You seam to know so much about the subjects your asking about, come up with 2 designs on your own, and we'll debat about those!


Dutch Peter

I actually can't say two classes with the same sail area straight off.... so I have to look for that.

I'll be back.

[Dutch Peter]

Here two others:

Hallberg Rassy 36:
L = 11,31 m
Lwl = 8,72 m
B = 3,55 m
Weight = 7,5 tonnes
Sail A = 65 m^2

Fisher 37:
L = 11,33 m
Lwl = 9,91 m
b = 3,66 m
Weight = 14,2 tonnes
Sail A = 61,4 m^2

Now you tell me?

[Tad]

Hey Dutch,

In looking at the first example, I agree the J will probably (undoubtedly) be better around a short triangle course on Sunday afternoon.

But, what about over, say, a month of gales in the Southern Ocean. In those circumstances might not the heavier, beamier boat (not necessarily the Catalina) end up ahead?

Best, Tad

[Slowmo]

Let's focus on main + jib only.

What does the designs tell you?

29'er (sail 12,5m2)
Spec: http://www.wet-windy.co.uk/2150_29er.html
http://www.29er.com/4027,275,1-0.html

international 420 (13m2)
http://www.420sweden.se/Assets/Pictures/index.htm
http://www.420sailing.org.uk/index.p...ba07543f210c30

international 505 (14m2)
http://www.irbs.com/directory/Dmoz/Sailing/Class_Sites/

It was my intention to find a flat bottom (2 or 3 chines) plywood sharpie, but so far I didn't find any typical example with 12-14m2 sail.


Sailingboats pages
http://dir.yahoo.com/Recreation/Outd..._of_Sailboats/
http://directory.google.com/Top/Recr...iling/Classes/
http://www.irbs.com/directory/Dmoz/Sailing/Class_Sites/

[Dutch Peter]

Originally Posted by Tad

Hey Dutch,

In looking at the first example, I agree the J will probably (undoubtedly) be better around a short triangle course on Sunday afternoon.

But, what about over, say, a month of gales in the Southern Ocean. In those circumstances might not the heavier, beamier boat (not necessarily the Catalina) end up ahead?

Best, Tad

Tad,

Your probably right, and not to mention the Catalina is more appropriate for that kind of sailing. but I understood the question as " in principal " waht boat is faster?

[Coen]

It is quite probable that a yacht or dinghy with the biggest Sail area, the longest waterline, the lowest wait, the smallest beam and the lowest block coefficient and prismatic coefficient will be the fastest (when none of the boats plane that is!)
But in transatlantic races as mentioned before, a little bit more comfort comes in handy because the crew will get tired because the seaworthyness is smaller.

Peter; In the 'Zeilen' (a dutch magazine) this month is a fun to read article about yacht design. I do not know if you read it, but it is interesting.

[Slowmo]

Originally Posted by Coen

It is quite probable that a yacht or dinghy with the biggest Sail area, the longest waterline, the lowest wait, the smallest beam and the lowest block coefficient and prismatic coefficient will be the fastest (when none of the boats plane that is!)

Do you say it's possible, or that it is likely

So there is a "simple formula" to find out the truth about this?

In wich order are they important?

Here is a 2-chiner, with a small 3'rd flat part in back.

http://devlinboat.com/dcnancyschina.htm
http://devlinboat.com/homebuiltoskari.htm

Do you se any bad design things about this boat for a stitch and glue design? Consider the hull.

[Coen]

Okay, I say it in an onther way:

A sailing dinghy is powered by wind
A sailing dinghy's underfinds drag from

• Wind
• Waves
• Wet Surface
• Weight (the higher the weight, the lower its acceleration and deceleration)

So if you will lower the drag or make the sail area bigger, the yacht will eventually go faster.

[Ilan Voyager]

A part the odd discussion about the fastest etc

A hard chine skiff running pretty well is the old Fireball. Designed for plywood. Planning like crazy. Look for plans in the internet. It's an international class with a lot of gadgets hardware on. Do not be fooled use the hull and put the rigging you need. It may fulfill your requirements.

In you look for a really fast thing about 12 sq of sail, take a class A solo catamaran. 5.5m long, 2.21m, mast 9m, 12.8 sq m of mainsail, about 75 kg. No jib. Run 2 miles/day, make some musculation, stop smoking and you'll see how it accelerates in a 12 knots breeze.

When you find that the class A is slow, go to next step. The 18 sq meter with at least 9/1 rachet block, big arms needed. Cat 5.5m width 2.8 to 3.2m about 90 kg. If you weight less than 85 kg take a water jacket. 90 to 100 kg of skipper's weight recommended if the wind is above 10 knots. Very fast for a solo cat, mortal upwind, points very well. The Tornado have difficulties for following. Accelerates like a big motorcycle and make feel the monohulls as small mopeds.

After that the Class C. Very expensive. Very high tech. But worth: 30 knots, 3 times the speed of wing going upwind, beating anything sailing in regatta. The Australian 18 footers have not the shadow of a chance.