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Discussion Starter · #1 · (Edited)
OK, I'll open myself up to more abuse! :rolleyes:

I find that my boat does not like running when sailing downwind. A beam reach to broad reach at most and she is fine. But a run with wind directly behind me slows her right down.

Even with the Gennaker I can't seem to go beyond a broad reach. Goose-winging with the jib sometimes helps.

Is this due to my large main sail, or just a characteristic of the M25? :confused:
 

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is this a feeling or is it gps confirmed?

most any boat will lose a bit of speed at 180 degrees however its flat and comfortable...

now if for example you lose 2 knots going from a very deep broad reach to ddw then maybe you havent adjusted you backstay and rake and vang, and sail adjustments appropriately for ddw

my 2c
 

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Beyond a broad reach the air flow across the sails is no longer 'aerodynamic' but inefficient 'impact' flow.
Welcome to the world of never going lower than a broad reach, and then 'tacking' downwind ---- much faster and more stable than impact/parachute DDW sailing.

The only problem you'll have with sailing this way, instead of DDW, is that you can easily exceed so-called hull speed ... and when you do your only job then is to keep the boat directly 'under' the mast (since you stated in an earlier post that you dont reef) so you dont trip over your keel or broach.

;-)
 

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When you get too deep on a broad reach the mainsail will shadow the genoa and it eventually collapses. Wing and wing DDW is not an easy course to hold for any length of time without a whisker pole a boom vang and a preventer rigged. That's a lot of work to set and unset on a lake. Taking down the mainsail and running under genoa could be a strategy but again, if you're sailing on a lake ( unless it's huge) and your course is going to need to change relatively soon it's alot of effort. Sailing broad reaches and gybing downwind is likely your best strategy.

If you've got enough wind and your boat sails well with a genoa alone..you could consider not using the mainsail. If I'm single handing and want a more relaxing sail..I will often just sail on the headsail. I lose a little pointing ability upwind...but who cares when you've got no where special to be.
 

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Beyond a broad reach the air flow across the sails is no longer 'aerodynamic' but inefficient 'impact' flow.
Welcome to the world of never going lower than a broad reach, and then 'tacking' downwind ---- much faster and more stable than impact/parachute DDW sailing.

The only problem you'll have with sailing this way, instead of DDW, is that you can easily exceed so-called hull speed ... and when you do your only job then is to keep the boat directly 'under' the mast (since you stated in an earlier post that you dont reef) so you dont trip over your keel or broach.

;-)
Rich (and anyone else),

Can I ask you to expand on this to help out a newbie, please? As I wrote in Merit's other thread about reefing, we got caught on our P26 w/ 92% jib and full mainsail in winds that were above our current limited experience level last week (15 knots with gusts above that); we were fine tacking back and forth and close-hauled while headed upwind, but had a terrible time downwind. We did, or at least thought we did, attempt to do what you're describing above; staying on broad reaches, and SLLOOOOWWWLLLYYY jibing (gybing? gybeing?) to cover the 10 nm or so back to our marina. The boat was corkscrewing (that's the only way I can think of describing the motion) like crazy with the waves, and the waves weren't that bad.. 2 foot at the most. There were times I really need to put some serious oomph into the tiller; my 5' tall wife wouldn't have had a chance.

What was going on? What forces caused that? What do you mean by keeping the "boat under the mast" other than making sure the boat doesn't turtle? :) You also said "tacking downwind;" does "tacking" in that case refer to the usual act of changing course to either side of your intended course as usual, or should we have been tacking through a 270 deg angle instead of jibing?

I realize we should have reefed. We'd never done it before, weren't sure HOW to do it (I know now... ), and the winds were only forecast to be 7 knots. I'd never do anything intentionally unsafe especially with my wife or anyone else on board, but we got caught and need to get back. Valuable lesson learned, and I'm grateful everything worked out.

Anything you can offer in terms of explanation of the boat motion we experienced and advice as to how to deal with it better would be most welcome.

Thanks, Jeff.

Barry
 

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I have just completed a 70nm DDW run, and being new to the boat I was eager to experiment. I started with 10-15kts true and tried broad reaching and jibing for a few hours. I found that broad reaching would put me at least 20-30 degrees off course so I was not making very good progress. On the other hand going wing on wing will only give me about 4kts or less boat speed. The gennaker would have definitely helped with sailing deeper angles but mine is quite brittle and I didn't want to risk ripping it in 4 ft following seas.

Later in the afternoon the wind started building in 16-19 range, and this is when wing on wing started working really well, giving me 6-6.5kts. Also the boat felt more stable due to increased pressure on the sails. I did not have much confidence in my autopilot at first but it was able to handle the boat surprisingly well and I had a great sail for the next 4 hours or so. I did not feel setting up preventer and the pole in those conditions was difficult or unsafe.
 

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Agree with all comments about broad reaching and gybing being faster and more stable than DDW. This can also be verified using a the VMG function on your gps.

Sailing DDW in a fin keel boat may result in wallowing. An inexperienced helmsman will try to correct for that, inducing more wallowing and perhaps an accidental gybe; just hold the wheel / tiller still and the boat will correct.

Running DDW takes much more concentration and staring at the windex is literally a pain in the neck.
 
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Simply put, it sounds like you were over-powered with too much sail up. The mainsail wants to drive you upwind and you have apply alot of helm ( rudder) to keep your heading downwind. Reefing would have alleviated that, How many reefs I don't know. Perhaps both sails needed to be shortened. Easy if you have a roller furling..and sail change if not.

One way to reef the main would be to head up and heave-to. You would be amazed at how things quiet down once hove-to. It also gives you a more stable platform to work on especially if you're shorthanded and have to go to the mast to reef. Then ease the main and lower it to the reef point. If you don't know how to heave-to, it would be good to practice..so you get to know how your boat needs to be set up.

In you're case..if home was all downwind...I may have even lowered the main altogether secured it and simply sailed home on the headsail.

You don't have to tack in order to gybe..but it is a strategy that you can employ, in high winds. Just be mindful that as you head up...you will begin to heel...you may want to keep the traveler down and the mainsheet eased somewhat..to reduce the amt. of heel.

Typically you'd want to do a controlled gybe by centering the boom 1st before putting the helm over, then letting it out quickly once on the new heading, thus reducing the violent motion of the boom swinging all the way across.
 

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The fastest and most efficient way to sail DDW is to use a whisker pole. The use of a pole allows you to sail deeper angles because it keeps the genoa open and increases sail area. This allows you to sail down wind without having to constantly gybe. Additionally, the whisker pole keeps the genoa from collapsing and improves the handling characteristics of the boat while sailing DDW.

There is a common misconception that whisker poles are hard to rig and hard to gybe. In reality, whisker poles are very easy to use. Many whisker poles are telescoping, which means that a single person can rig the pole and then set the correct length by themselves.

I've attached some links explaining the benefits of using a whisker pole. I personally use whisker poles every time I sail DDW and have had great success.
 

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Simply put, it sounds like you were over-powered with too much sail up. The mainsail wants to drive you upwind and you have apply alot of helm ( rudder) to keep your heading downwind. Reefing would have alleviated that, How many reefs I don't know. Perhaps both sails needed to be shortened. Easy if you have a roller furling..and sail change if not.


We have hank-on sails, and the working jib was the only headsail we had onboard. Our main has one reef point. At the time, I was under the stupid impression that one needed some sort of specialized system rigged to utilize those cringles, but we could have just used any sections of line to lash the clew and tack reef points to the boom, right? Not the most elegant solution maybe, but it would have been a lot better than what we did.. which was nothing.

One way to reef the main would be to head up and heave-to. You would be amazed at how things quiet down once hove-to. It also gives you a more stable platform to work on especially if you're shorthanded and have to go to the mast to reef. Then ease the main and lower it to the reef point. If you don't know how to heave-to, it would be good to practice..so you get to know how your boat needs to be set up.

We did practice heaving-to one the way out. Loved it. Very easy to do, very stable, and a great way to take a break for a bit.

In you're case..if home was all downwind...I may have even lowered the main altogether secured it and simply sailed home on the headsail.

You don't have to tack in order to gybe..but it is a strategy that you can employ, in high winds. Just be mindful that as you head up...you will begin to heel...you may want to keep the traveler down and the mainsheet eased somewhat..to reduce the amt. of heel.

Yeah, we felt the boat's desire to heel kick in quite strongly whenever we fell off at all when heading upwind.. the initial turn to a downwind heading was pretty exciting. I had eased the main a good bit prior to the turn, but I probably should have/could have just let it go entirely until the turn was complete to minimize the heeling.

Typically you'd want to do a controlled gybe by centering the boom 1st before putting the helm over, then letting it out quickly once on the new heading, thus reducing the violent motion of the boom swinging all the way across.

That's exactly how we did the gybes. We did it four times; three out of four were very well controlled, but one of them I got the timing wrong and the boom moved a little faster than it should have. We were ready for it, and it didn't travel far.

Thanks so much for the help. Next time, per your advice, reef or sail downwind just using the headsail... got it!

Grrr.. I just saw how this got posted. Most of my replies are embedded in your original quoted post above. How do you folks break up posts into excerpts so replies can be placed next to the relevant phrases?


Barry
 

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OK, I'll open myself up to more abuse! :rolleyes:

I find that my boat does not like running when sailing downwind. A beam reach to broad reach at most and she is fine. But a run with wind directly behind me slows her right down.

Even with the Gennaker I can't seem to go beyond a broad reach. Goose-winging with the jib sometimes helps.

Is this due to my large main sail, or just a characteristic of the M25? :confused:
The Merit 25 is an actively raced boat. With a minor amount of searching you should be able to final a polar graph for it. That will show you target speeds for a given true wind speed and angle.

On almost all boats running dead downwind is slower than doing a broad reach and jybing. When you are on a broad reach the sail still has lift and the apparent wind will shift forward and on a fast boat like the Merit 25 you should be able to approach or potentially exceed the true wind speed. Going dead down wind there is no lift, the sail is just being pushed, and you'll never go as fast as the true wind speed.
 

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Even with the Gennaker I can't seem to go beyond a broad reach.
As noted above, sailing deeper than a broad reach is all about projected area. If your gennaker is larger than your main you are likely to go faster with the main down and just the gennaker up.

I found that broad reaching would put me at least 20-30 degrees off course so I was not making very good progress. On the other hand going wing on wing will only give me about 4kts or less boat speed.
Right. Trigonometry is your friend. Lets use 4 kts DDW as a base. If you are 20 degrees off course (cos(20) = 0.94) anything faster than 4.25 kts improves your velocity made good (VMG) toward your destination. 30 degrees off course (cos(30) = 0.87) anything faster than 4.6 kts improves your VMG. Intuition is not your friend - boat speed is and it doesn't take much to get to your goal more quickly.

Grrr.. I just saw how this got posted. Most of my replies are embedded in your original quoted post above. How do you folks break up posts into excerpts so replies can be placed next to the relevant phrases?
Magic. *grin*

When you click on the quote button, or hit multi-quote (the +" symbol) and the post reply, you'll see the material you are responding to in the reply box.

You'll see the quoted material surrounded by something that looks like QUOTE=bblument;2094841 with square brackets around it at the beginning and /QUOTE with square brackets around it at the end.

Just break up the quoted material into the blocks you want to respond to with copies of the QUOTE text (including the square brackets) at the beginning of each block and /QUOTE (including the square brackets) at the end of each block.

Leaving out the square brackets this current message looks like this:

QUOTE=Merit25lovers;2094345 quoted material /QUOTE

my response

QUOTE=skalashn;2094737 quoted material /QUOTE

my response

QUOTE=bblument;2094841 quoted material /QUOTE

my response

The QUOTE and /QUOTE are not actually case sensitive. The numbers after the semi-colon generate the > icon that links back to the original post you are quoting from.

I hope this helps you.
 

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DDW, as others have noted, is a difficult point of sail. Better to tack off a bit to keep wind in the sails without trying wing and wing unless you're set up for it. The most important lesson we all learn is to reef when you first get the inkling you may have to reef. It's risky and exponentially more difficult once you get overpowered. It is sooo easy to under-calculate a following wind because the apparent wind on deck seems less. I bet everyone on this forum has probably learned this lesson the hard way:)
 

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Beyond a broad reach the air flow across the sails is no longer 'aerodynamic' but inefficient 'impact' flow.
Welcome to the world of never going lower than a broad reach, and then 'tacking' downwind ---- much faster and more stable than impact/parachute DDW sailing.

The only problem you'll have with sailing this way, instead of DDW, is that you can easily exceed so-called hull speed ... and when you do your only job then is to keep the boat directly 'under' the mast (since you stated in an earlier post that you dont reef) so you dont trip over your keel or broach.
Further to what Rich states, your apparent wind is lowest going DDW, which is another reason DDW is slower than even a very deep broad reach. As your apparent wind approaches 0 knots because of a following sea, you will have very little water moving past your rudder in the right direction and can lose steerage, making boat handling somewhat squirrely -- technical term ;). Altering your course even 10-15 degrees from DDW will be easier to handle, faster (better apparent wind) and reduce the risk of an accidental jibe.

Chris
 

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Also, I noticed that you are using an asymmetric spinnaker. These have a flatter luff that is cut for reaching and not DDW sailing. The Merit 25 was originally made for a symmetric spinnaker, if you have one you'll probably find it faster when sailing deep.
 

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SVAuspicious said:
Right. Trigonometry is your friend. Lets use 4 kts DDW as a base. If you are 20 degrees off course (cos(20) = 0.94) anything faster than 4.25 kts improves your velocity made good (VMG) toward your destination. 30 degrees off course (cos(30) = 0.87) anything faster than 4.6 kts improves your VMG. Intuition is not your friend - boat speed is and it doesn't take much to get to your goal more quickly.
You are absolutely right. However on my boat I found that under 15 kts true it would probably take close to 40 degrees off course to achieve any real speed improvement over wing on wing. Above 15 wing on wing would be just as fast as broad reach.
 

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You are absolutely right. However on my boat I found that under 15 kts true it would probably take close to 40 degrees off course to achieve any real speed improvement over wing on wing. Above 15 wing on wing would be just as fast as broad reach.
Even 40 degrees isn't bad - just 23% different. For a 4 kts base speed you need 5.2 kts for equivalent VMG.

As the wind picks up you can go deeper and maintain boat speed and build VMG.

My point was that no one is making up the benefits of gybing downwind. It isn't hard to get 25 - 30% more boat speed heading up a bit in light to medium air.
 

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while true I have noticed that novice helmsman will hunt for speed too much paying little attention to where they really need to be

B from A

I would often tell the kids at the sailing school that to start off, its ok to go slow but steady and straight versus tacking and gybing every other minute trying to chase the best boat speed

this is very apparent(no pun intended) on wallowy downwind courses or after the reaching leg of a small race course...

there where always those kids that started gybing back and forth back and forth and then you would see the steady as a train kids that for the most part would always arrive at the last mark faster...

this applies to all boats really, all helmsman.

fidgety is good sometimes but not always...jajaja

a balance they say.
 
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