Heavy sailboats are slower and

[wingssail]

Originally Posted by waterman46

Such an occurence will be rare, and random. The usual case is that since the lighter boat accelerates faster, it can take advantage of brief puffs of wind that will leave a heavier boat just stalled.

It's quite complex, there are many variables.

We often race against a much more modern and lighter boat. It has 4' more waterline and larger sail area. They usually are faster than we are.

But in light upwind conditions we point higher and sail faster. Why? We have a big genoa, they don't have overlapping headsails.

In really light conditions, (0-4 kts) under spinnakers, we sneak away. Why? their broad hull has much more wetted surface and it results in more drag.

So all these generalizations are just that, generalizations. There is more going on than this.

[MarkSF]

I was watching with interest the Transpac race a few years ago. The first couple of days were sailing upwind, with higher wind speeds, and fairly rough seas. Which boat was in the lead in those conditions? A Westsail 32 - by any standards, very heavy indeed. It was ahead of many much longer, and wider, and lighter boats.

When the wind dropped and veered to it's more normal light tailwind, the light boats streaked ahead.

PHRFs only give an average of all points of sail, at one wind speed.

[CarinaPDX]

Teaching yacht design a piece at a time doesn't work. The OP should find some good books, or perhaps listen to the Crealock video. There is little simple about design trade-offs, and for most statements there are exceptions. Understanding the entire package takes some knowledge. And there is always the theory versus the practice.

He is right that the costs of a boat are heavily correlated to the displacement, ceteris parabus (other things being equal) - but they are often not equal. A production boat built to keep the costs down and provide a lively sail will be less expensive per pound to build than a heavier production boat, hence the evolution of lightweight mass-produced boats. But custom racing boats built with epoxy and engineered fabric (e-glass, kevlar, etc) will be very much more expensive. And if you are looking at used boats you can often find older heavy boats at a real bargain. Also it is not uncommon to find the very light boats with issues like excessive flexing or other problems.

The discussion of healing partly misses the point: many older designs like mine are designed to sail at 15°-20°, which increases the water line length (gotta love those old overhangs!) which in turn increases hull speed. And the bowsprit makes for a very large sail area/displacement ratio (17.3 in Carina's case). So she may be very heavy for her length but not for her sails.

The whole issue of sea-kindliness (i.e. comfort of motion) is often simplified. A heavy boat is going to respond to conditions more slowly while a lighter boat will have a quicker motion. You can think of this as the difference between an old Cadillac and a sports car - crossing the continent on the freeway is going to be more comfortable in the Caddy, and the sports car is going to be more tiring. OTOH driving a winding road is going to be a lot more fun in the sports car. Size is a decidedly mixed blessing - the further one is from the center of rotation the more a body is moved for the same angle of pitch/roll/yaw (hence sleep as close to the middle of the boat as possible). Against that is a possible reduction in the angle with size. Combine that with the slow/fast accelerations and rotations and the rides can be quite different.

My point is that any design is a collection of trade-offs, ultimately of costs, performance, maneuverability, sea-kindliness, comfort, safety, and a myriad of other concerns. You have to look at the package as a whole. As far as choosing what is right for you first do some reading but then get some experience; volunteer to crew on others' boats and learn what works for you. And whatever type of boat you get, just be sure that she is built well and will pass survey before putting to sea - not even all new boats will pass this test.

Greg

[barnakiel]

Extra stability from extra speed can be observed watching flat fast boats and foilers.


E.g.

https://www.youtube.com/watch?v=E0gb0Lb2gzM

This is one of the slower boats that will not compete with a well sailed W32 ;-)


The Internet is full of such snippets. Just watch, think, enjoy.


Love,
b.

[CarinaPDX]

Originally Posted by MarkSF

I was watching with interest the Transpac race a few years ago. The first couple of days were sailing upwind, with higher wind speeds, and fairly rough seas. Which boat was in the lead in those conditions? A Westsail 32 - by any standards, very heavy indeed. It was ahead of many much longer, and wider, and lighter boats.

When the wind dropped and veered to it's more normal light tailwind, the light boats streaked ahead.

PHRFs only give an average of all points of sail, at one wind speed.

Her name is Saraband, out of Portland. She was prepped as well as any other boat in the fleet. The bottom was taken down to bare gelcoat, carefully faired, and all through-hulls were countersunk. A racing bottom paint was applied, then a teflon speed-coat was over-coated. She had a purpose-built heavy nylon, full 180° spinnaker. I was told she held 8 knots under spinnaker the whole way once in the trades. So she was a high-performer for her design.

The real point is that the committee used the standard PHRF rating for a W32, and only once the race had begun did they realize their mistake. The rating (Performance Handicap Rating Formula) was based on previous W32 race results, much on closed courses where the W32's poor windward performance had an impact. The rating was arguably wrong for a downwind race, and argue they did. There were lively discussions as to whether the rating should be changed - during the race! Unfortunately this tied into a narrative of Portlanders perhaps not always being treated fairly in this race - another story. In any event, the fast sleds were in Ala Wai partying long before Saraband showed up.

Greg

[CarinaPDX]

Originally Posted by barnakiel

This is one of the slower boats that will not compete with a well sailed W32 ;-)

For a cruising couple crossing an ocean I think the W32 is a far safer choice...

Speed Kills

Greg

[wingssail]

Originally Posted by NormanMartin

...A great video on the subject is here:

The speaker Bill Crealock is very articulate and the 58 minute video goes by quickly...

I just watched the video. It was entertaining. However, while I found that he had a lot to say that I agreed with, and I have sailed some of his boats, notably considerable time on West Sail 42's, and Westsail 32, I was disappointed that such a well known designer could spout so much BS.

So many things he said, mostly in reference to "race boats" were things I know not to be true.

A lot of what passes for "common knowledge" is based on myths and is simply wrong. But Crealock's audience was eating it up and knowingly and enthusiastically nodding in agreement.

[CarinaPDX]

"Half of what you know is wrong."

The difficulty is 1) believing it, and 2) working out which is right or wrong.

For some it is more than half...

Greg

[ramblinrod]

Originally Posted by agpilot88

Question:


This is the way I understand it. The heavier the boat, the more stable and slower it is and the lighter the boat the quickler and less stable it is?


Correct?


Of course take into consideration of the draft and the shape of the hull. Seems like price and weight corresponse with each other.


Lee

Too simplistic. There are many more parameters affecting stability and speed that just weight. In a simple apples to apples comparison, two identical boats, the one carrying 500 pounds more will be theoretically slower, as it will displace more water, which will take more power to move the same speed as the identical unloaded vessels. But the big J boats are heavier than my full keel 32 foot boat. They are both faster and more stable because they benefit from a number of factors that affect speed and stability like LWL, beam, sail area, etc.

[boatman61]

Originally Posted by barnakiel

Extra stability from extra speed can be observed watching flat fast boats and foilers.


E.g.

This is one of the slower boats that will not compete with a well sailed W32 ;-)


The Internet is full of such snippets. Just watch, think, enjoy.


Love,
b.

Love to see it performing in 4metre seas and 35kts of wind..

[wingssail]

Originally Posted by boatman61

Love to see it performing in 4metre seas and 35kts of wind..

Yes, it's quite a stretch to image how these boats will ever evolve to a cruising boat which can sail in 4 mt seas and 35 kts of wind.

[wingssail]

Originally Posted by CarinaPDX

The whole issue of sea-kindliness (i.e. comfort of motion) is often simplified. A heavy boat is going to respond to conditions more slowly while a lighter boat will have a quicker motion. You can think of this as the difference between an old Cadillac and a sports car - crossing the continent on the freeway is going to be more comfortable in the Caddy, and the sports car is going to be more tiring. OTOH driving a winding road is going to be a lot more fun in the sports car.

Greg, we've all heard this so many times nobody even questions it anymore, but if you are going into waves and your heavier boat, with weight in the ends, dives off a crest of a wave and plunges the bowsprit deep into the next wave, then rises off of that one with tons of water on the foredeck, and repeats this over and over...and they are going 2 kts and the motor is straining...

I don't see how that is more comfortable than a boat with a faster motion which rides up and over every wave, going 5-6 knots, and the motor is off.

One is plunging, the other is slamming.

People with heavier boats, always motoring when the wind is on the nose, seem to complain more about the conditions than other people who sailed their lighter boats upwind through the same conditions.

And considering the Cadillac and a sports car...a good road car has a firm suspension and is light in the ends.

[boatman61]

Originally Posted by wingssail

Greg, we've all heard this so many times nobody even questions it anymore, but if you are going into waves and your heavier boat, with weight in the ends, dives off a crest of a wave and plunges the bowsprit deep into the next wave, then rises off of that one with tons of water on the foredeck, and repeats this over and over...and they are going 2 kts and the motor is straining...

I don't see how that is more comfortable than a boat with a faster motion which rides up and over every wave, going 5-6 knots, and the motor is off.

One is plunging, the other is slamming.

People with heavier boats, always motoring when the wind is on the nose, seem to complain more about the conditions than other people who sailed their lighter boats upwind through the same conditions.

And considering the Cadillac and a sports car...a good road car has a firm suspension and is light in the ends.

I take it your not refering to seamen in the above post.. in those conditions I'd be hove to sipping coffee with a good book down below..

[GWB]

Originally Posted by MarkSF

I was watching with interest the Transpac race a few years ago. The first couple of days were sailing upwind, with higher wind speeds, and fairly rough seas. Which boat was in the lead in those conditions? A Westsail 32 - by any standards, very heavy indeed. It was ahead of many much longer, and wider, and lighter boats.

When the wind dropped and veered to it's more normal light tailwind, the light boats streaked ahead.

PHRFs only give an average of all points of sail, at one wind speed.

Which race were you watching Mark?

[fatherchronica]

We have owned 2 racing boats with about 50% ballast ratios and wide flattish hulls very stable and fast. We now own a near 50% ballast ratio with a narrow really heavy hull. Also very stable. We are happier sailing to windward in big seas and weather in our current boat as she very rarely pounds and we almost never, and I do not understand why, get blue water on board. For the record, the highest speed I can document on any boat I have ever owned is 14 kts on Mana, but we were surfing down large seas, with I might add 2 kts of current helping us along. When we bashed back from Mexico we did note that several folks we knew shipped their lightweight cruisers North and we never met any lightweight cruisers bashing back that did not have delivery crews as they have much more tendency to beat you up. Not to say we did not have 3 days of miserable sailing coming up though.