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Master Mariner
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Discussion Starter #1
So often on here and other forums I hear the question; how long from X to X?
For those of us who had our boats a season or two, the answer is pretty simple.
So, on a good day, working sails only, what % of the wind speed would you expect to make, up to around 20/25 knots on a beam reach to a hard beat?
I guess it sounds an odd question, but I'm always trying to increase my performance in relation to wind speed.
 

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Not quite sure what the question is...
Beating seems slower as wind pipes up as waves slow you down more...
Light conditions and flat seas closer to the wind is a faster point of sail for Shiva... more apparent wind.
Beam and abaft of the beam wants more wind... but the waves seem to be less of a problem.

This is not the answer you want but I can't understand the % thing.
 

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Master Mariner
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Discussion Starter #3
OK, I'll try again. Working sails only.
Obviously more wind, less sail to reach an optimum speed. Less wind means more sail to keep that optimum speed. Only works in a beam wind to hard on it. In that "slot" would you expect your boat speed to be around 40, 50, or 60% (or other) of the apparent wind speed? We do our best between 8 knots of wind and 18. After 18 the wind gusts too much to maintain a good average and the seas begin to affect the boat too much.
 

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Need to define whether you are talking about apparent or true wind speeds and angles.

An AWA beam reach up to 20kts AWS and we expect ~70% of that wind speed, although we are needing to reef at the higher end.

A beat at 32-35* AWA up to 20kts AWS and we expect ~50% of that wind speed, but again, we are needing to reef at the higher end.

After 20kts apparent, we pretty much keep the same speeds and angles, but are reefed. At 25kts apparent, we are beginning the second reef, and speeds drop to ~50% beam AWA beam reach, and ~30% AWA beating - mostly because the waves are taking their toll.

Mark
 

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Is this exercise for planning purposes? When I am voyage planning I assume an unknown wind speed and collect data based on average VMG for the boat in all past conditions. I would typically assume higher VMG for areas of open water vs rivers, creeks and protected waters. I will make adjustments for very favourable conditions vs is unfavourable conditions. On average I assume the following;

Beach Cat 5 knots vmg (seems low but that is a calculated average obver 1000 miles).

Sharpie; 3 3/4 knots. She cooks in light air.

Sailing kayak. 3.2 knots. This is a remarkably stable number. I can almost gaurantee it will take me within an hour either way to cover 32 miles in 10 hours.
 

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Old soul
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I may not fully understand the question, so forgive me if I’ve got this wrong...

(I know you know all this…)

First off, I assume we’re talking apparent wind. Secondly, sea state matters big time. No seas, opposing seas, angled seas or following seas will affect progress.

That said, my boat will usually achieve hull speed on a reach to close-reach, as well as DDW, with 20-25 knots wind. For us this means a bit over 7 knots (theoretical hull speed is around 7.4 knots). I expect to see this anytime wind is around 15+ knots, again depending on sea state.

Close haul and broad reach is where we perform poorer. Here best speed might be around 6 to 6.5 knots.

For planning purposes I usually use a 5 knot average.
 

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That said, my boat will usually achieve hull speed on a reach to close-reach, as well as DDW, with 20-25 knots wind. For us this means a bit over 7 knots (theoretical hull speed is around 7.4 knots). I expect to see this anytime wind is around 15+ knots, again depending on sea state.

Close haul and broad reach is where we perform poorer. Here best speed might be around 6 to 6.5 knots.
Curious why your performance DDW is better than a broad reach? Is it because you are wing-wing DDW with better projected sail area?

Mark
 

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Don't the boat's polar diagrams answer your question?
Yes, that is the real answer for a particular boat, but most don't have polars available. And most polars are calculated, which are always optimistic.

However, your point is what should be done - use the chartplotter/tablet/computer application to show VMG on a course and tweak around with sail set, wind angles, tacking/jibing, etc.

Mark
 

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Old soul
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Curious why your performance DDW is better than a broad reach? Is it because you are wing-wing DDW with better projected sail area?
Exactly. Wing and wing downwind. Sometimes using the two foresails.

A broad reach turns out to be a challenging position for us because of the way our massive main blankets the foresails. I find it hard to maintain much foresail, especially in a rolly sea, on a broad reach.
 

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I don't use percentages of wind speed because it doesn't work for my boat
As it's quite light it will get close to hull speed easily. Then I keep it there as the wind increases by reefing.

Planning I use 2 speeds 5.5 knots and 6 knots and I find I am a little in front of that every day. Especially during passages I sail conservatively... The last thing I want us breakages. So if I am near hull speed I will back off.

🤪
 

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I don't think there is a consistent percentage, not to mention it's speed over ground that matters between X and X, so variable current and wave action matter too.

We just installed new Quantum sails and gave them their first test drive in 11 kts of wind. On the beam, we were making 8.5 kts over the water. Genny is a 150. Best money I've spent on the boat in a long time! I expect I'll be re-establishing my reefing speeds. :)

Your question reminds me of something my (now grown) kids remind me of, all the time. As kids, I would get the typical (how much longer) question repeatedly. My answer was usually, "about 3 hours". An hour later, they'd ask again and my answer would be "about 3 hours". They now say that everything is 3 hours away, don't ask. :)

While I had likely tacked more than expected, or found current or head waves I didn't expect, they just came to think I had no idea. That was demonstrably true.
 

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Master Mariner
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Discussion Starter #15
Thanks, all. I was just a shot in the dark. I'm pretty comfortable when I can exceed 50% of apparent wind speed under most conditions, either on a beat or beam reach.
"Schedules are a fool's errand" is a pretty simplistic sentence. ALL of us sail on some kind of schedule. Each and every one of us! We go on a day sail and need to be back at a certain time for one reason or another. Some sail by weather windows and others have guests aboard who have a flight to catch at the end of the voyage. The Commuter cruisers sail on a schedule, so many months sailing and so many months with the grandkids. And if you ever skipper a delivery thinking you aren't on a schedule, that will most likely be your last one.
Folks are just fooling themselves when they say they aren't on a schedule of some sort. Just think of all those day sailors on here who fear being out after dark!
If most cruisers didn't have some sort of schedule, they might be caught in a hurricane or sit in some idyllic bay forever, which would be tantamount to being in some old folks home waiting to die, just with more maintenance.
 
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Just think of all those day sailors on here who fear being out after dark!
Well, it's scary out there ;)

You forgot about lunch! You need to know how much food and bevvies to bring :) My wife is pretty tolerant of my sailing, but if I didn't bring enough snacks because I packed 3 days worth of food for a 5 day trip, I am pretty sure I would be sailing on my own after that. :|

I frankly can't imagine heading out on any trip whether it be a day trip or a multi day passage without having at least a rough idea of how long it was going to take.
 

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Old soul
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Yup, we all plan — make plans. Some things are dictated by Momma Nature. Others by Human Nature. And most of us face limitations due to social/economic demands.

We better have a rough idea about when the next provisioning stop will be, otherwise mutiny might follow. And we better not run out of coffee or wine!!!

Within all that though there can be a wide range of plans — no-plans. I like to have very loose plans when we cruise. We usually have a general idea, or perhaps even a destination in mind. But then I try and give ourselves the most possible time to do it in.
 

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I think the belief that a schedule is dangerous is one based on insisting on leaving at a given time or date irrespective of impending weather but of course one has an expectation of the duration of a trip/voyage.

On a crossing I budget 150nm a day and generally try to achieve that even if quiet periods mean a little motor sailing. That’s a nudge over 6kn average speed. I’m not one to sit around drifting when the wind goes AWOL. After all, we have to charge batteries or run the water maker now and then.

I try to never beat on a crossing. If I had to develop a polar for my boat it would ignore anything forward of a tight reach. I run a 135% genoa until the wind gets back to the quarter then if AWS is 15kn or less the gennaker goes up.

I met a German fellow cruising many years ago who said that when his decks got wet he knew he was doing it wrong :)
 

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Discussion Starter #19
Yup, we all plan — make plans. Some things are dictated by Momma Nature. Others by Human Nature. And most of us face limitations due to social/economic demands.

We better have a rough idea about when the next provisioning stop will be, otherwise mutiny might follow. And we better not run out of coffee or wine!!!

Within all that though there can be a wide range of plans — no-plans. I like to have very loose plans when we cruise. We usually have a general idea, or perhaps even a destination in mind. But then I try and give ourselves the most possible time to do it in.
Is it the air around Newfoundland or is it just coincidence both you and the author of "The Boat that Wouldn't Float" seem to have the same outlook on life? lol
 
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bell ringer
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on a beam reach, 5-7 knots after around 12 knots wind because I start reefing down around 6.5 once the first gust takes me to 7+
 
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