How close to wind?

[Martin S]

How close to wind can your yacht sail? As a new Malo 39 owner, I'm interested in performance of similar yachts. If someone can point me in the direction of performance charts (polar diagrams) for a Malo 39 even better! All comments welcome.

[Stumble]

The easy way is to contact US Sailing and buy a copy of the theoretical tables for about $150 here Laminated Boat Speed Targets . These are based on measurement date, and so they will be inaccurate, but at least give you a good start. You can also buy the hardware and software than converts NMEA data (wind speed, direction, and boat speed) into polars. Generally race boats start with the theoretical data as a starting point and refine it with as measured data. The hardware doesn't take much more than a laptop and installed instruments, and the software isn't very much either.

The downside for a cruiser is that unless you are sailing at lightship weight, with new sails, good crew, and working the boat for speed you will never hit the numbers. So updating the table with new, bad information won't help.

[CarstenWL]

... even easier should be to contact Malö in Sweden (Malö Yachts AB) and ask for the data.

Regards,

Carsten

[jreiter190]

'Bout 7 degrees, how 'but yours?

[Jim Cate]

Originally Posted by jreiter190

'Bout 7 degrees, how 'but yours?

7 degrees of what??

Jim

[Jim Cate]

For the OP:

While the theoretical polars are interesting, as others have said they have little relevance to how your boat will sail... with your loading, sails, hull smoothness etc. If you really want to know about your own boat, some data gathering is needed.

Sailing with the best trim you can generate, make a few tacks spaced far enough apart to get the boat back in the groove for a ways. Then examine your recorded tracks on a plotter or OCPN, and measure the angle between the tracks. obviously, one should do this in an area with no current (may be hard to find!).

The results will be skewed by sea conditions, wind speed, wind shear, and other arcane factors, but you will have started the data collection. Repeating under different conditions will add to your trove of real world knowledge.

Or you can do what most sailors do: pinch up untill nearly stalled, look at the AWA on the windpoint gage, and claim that angle for how your boat sails to windward!

jim

[Dockhead]

Originally Posted by Jim Cate

. . .

Or you can do what most sailors do: pinch up until nearly stalled, look at the AWA on the windpoint gage, and claim that angle for how your boat sails to windward! . . .

Tee hee.

"How close" is not at all the question.

How well a boat performs to windward is better expressed as the tacking angle over ground, at optimal VMG to windward.

Anything under 100 degrees is doing really well for a loaded cruising boat.

I sailed a couple thousands miles upwind last year and swore to improve my boat's upwind performance, and spent several tens of thousands of dollars on it last winter.

My stated goal was not the tacking angle, but VMG to windward -- I wanted 5 knots over a reasonable range of conditions.

With new carbon laminate sails I got a dramatic improvement in upwind performance, and perhaps I'm getting those 5 knots VMG to windward, although I'm not completely sure yet.

It's a lot of expense and trouble to gain the capability to make miles efficiently to windward.

It's very satisfying, and I'm glad I've been through the exercise. But after having done it, I now have new respect for motor sailers.

[charliehows]

Been wondering...; can an average cruising yacht make better SOG directly into the wind sailing or motoring ie; tacking vs motoring directly into the wind? I'm fairly sure motoring is the winner but who knows?

[jreiter190]

I believe most sloops can make better overall progress in moderate conditions with the mainsail sheeted in and the engine going. Care must be taken to balance the driving force of both so one doesn't cancel the other.

[arsenelupiga]

i know mine can do 30 deg app when hand steering. As I am too lazy, use autopilot nearly 100% of time and 40 to 45 deg wind-wane setting. This translates in around 60 true in low winds and decreases to 50 true in higher winds. If waves not too bad in higher winds, can pass 5 kn progress against weather as boat happily sails 8-10 kn against weather in not too bad conditions and 20+ kn true.

However, I do not practice this sailing much to be gentle on boat.

Wave action has negative impact on windward ability in low winds, more than mono.

[Martin S]

Thanks Jim for a pragmatic and practical answer, much preferred to Dockhead's throw more money at it solution, that may come later.
Thanks all.

[carstenb]

Martin, this will also be dependent on how you rig your boat. If we're going sailing up waind all day, I rerig and move the juib sheets inside the shrouds, that gains me a couple degrees on the angle. Also - what sails are you using? 140% genoa? or a 100% jib? or?
Are they furling sails or hanked on? And then there's also how much weight you're carrying.

Jim advice is good - go out on a day with pretty consistent wind and take some long tacks. Trim up as tight as you can without pinching and see what you get.

[Martin S]

Carsten, boat was previously rigged with overlapping genoa, now has new 100% (furling) jib, also new main. That would be the theoretical difference between overlapping genoa and 100% jib?

[carstenb]

Originally Posted by Martin S

Carsten, boat was previously rigged with overlapping genoa, now has new 100% (furling) jib, also new main. That would be the theoretical difference between overlapping genoa and 100% jib?

I'm afraid I can't tell you. But generally the larger the genua the further from the wind you can sail. The smaller the jib the closer you can get.
As Dockhead noted - when he switched to carbon fiber sails he improved his windward performance quite a bit.

There are many factors involved in windward performance, not the least of which is sailtrim and helmsman skills.

I'm afraid you're back to take the boat out and see how she sails. You'll probably also find that she favors one tack (most boats do). Why? Dmaned if I know, could be the shape of the hull, balance of the load, and million other things.

Our Sun fast favors the starboard tack by about 2-3 degrees. Never have figured it out

[7623]

For upwind performance you need good sail shape. An old worn out sail will perform nowhere near as well.

When reaching an old sail can be a good thing, especially in light winds.