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rbyham 02-01-2014 07:50 AM

Closer to the wind question
 
First year sailor here...

Yesterday and Monday were sailing days here in the harbor. In both cases I was trying make the harbor coming from above or North with wind out of the South. I suppose I could have just up the faithful Atomic 4 and Motored down in about 20 minutes but I wanted to add if I could sail it down. Wind was blowing Monday a steady 10 gutting 13 no big deal but increased wind was forecast so out of marina I set main with one reef and pulled out the genoa to about 90. In this configuration I could sail no closer than about 30 degrees requiring fast and furious tacking in narrow channel. I was about to give it up drop sail and hit the starter. But as I rolled genoa first I found the heading coming harder on the wind under just the main. I was now about 20 off the wind and almost on a heading that would work. At that point I wondered about motorsailing so fired up the A4. She caught immediately as is her practice though it is had to tell in a breeze as she makes so little sound :-). Anyway, I was now very hard on the wind with course and speed to bring me nicely into the harbor for a great afternoon.

My question is, why did dropping the headsail help? I guess I always thought that close on the wind required headsail and yet everything improved once I was under main only which improved again with a light (800 rpm) motor assist. I am confused. I should add I was sailing with a 2 knot current on falling tide.

What is the lesson in all of this?

paulk 02-01-2014 08:39 AM

Re: Closer to the wind question
 
Lots of variable things going on in your scenario, so it's hard to pinpoint any one thing. First off, for pointing higher under just the main. This may be because you slowed down when you rolled up the genoa. You don't mention your actual boatspeed anywhere in your post. Slowing down will bring the apparent wind aft - creating a lift for yourself. It could also be because your main is cut flatter than your jib. Since you're traveling up a channel, in current, there could also be things going on with that which might enable you to head higher (or lower). All in all, you sail with what you've got or start the engine, as you say you did.

Sailormon6 02-01-2014 09:02 AM

Re: Closer to the wind question
 
In order to sail closest to the wind, you have to generate the maximum possible speed, and the sailplan and sail trim must be balanced.

We can only guess, based on your description, but my guess is that the jib was trimmed too full. If the jib is too full, the boat can't point as close to the wind as it can if the jib is flatter. Because of the fuller shape of the jib, the bow is pulled off to leeward.

When you took the jib out of the equation, the boat lost speed, but, because the jib wasn't pulling the bow to leeward, it appeared that the boat was sailing closer to the wind. I don't think it was actually sailing closer to the wind, because the slower speed, when you furled the jib, meant that the keel wasn't generating as much lift, and the boat was undoubtedly drifting to leeward more.

My suggestion is to try trimming the jib a bit flatter,a but remember that there is a point where the jib can be too flat. You need to find that ideal sail trim that enables the boat to generate a combination of the best speed and the best pointing angle. You'll find that by experimentation and experience.

Faster 02-01-2014 09:37 AM

Re: Closer to the wind question
 
I'm willing to bet you were MUCH slower but higher with mainsail only..

JimsCAL 02-01-2014 09:43 AM

Re: Closer to the wind question
 
What you were doing with the genny rolled up, main inn use and motor running was motor-sailing. This will allow the boat to move forward decently closer to the wind as the sails don't have to provide all the drive. Not a bad way to go in the situation you describe as you don't have to tack constantly in the narrow channel and you have the sail as a backup in case the engine dies. One thing to consider is that some engines may get starved for oil if you heel excessively.

lancelot9898 02-01-2014 09:44 AM

Re: Closer to the wind question
 
To understand how your boat behaves, it is best to change one parameter at a time. Also I find it easier to understand by using the true wind direction rather than apparent wind since apparent wind direction will change depending on your boat speed.

The most efficient way of sailing close hauled is with both the head sail and main. However, if you desire to luff up and give up some speed then pointing higher will be possible with main sail only. That is because your head sail will luff earlier than the main. I find that when motor sailing that the head sail should furled and the main pulled in tight to improve windward ability. Going further to windward is possible, but then at some point the main will be luffing and that too must be taken in. Also ability to point will be impoved with following current.

bobperry 02-01-2014 10:06 AM

Re: Closer to the wind question
 
Think VMG.
You can jam almost any boat up on the wind but I can assure you that with an AWA of 20 under main alone your VMG should have been dismal. The typical boat can limp along under main alone but takes off when the genny is deployed.

But different boats behave differently and I was not there.
However I remain highly skeptical that you saw a true "improvement" in performance if improvement is measured by VMG. Your improved AWA is most probably due to the fact that the spreaders and cap shrouds limit how much you can sheet in your genny. The main could be hauled up to weather if you like as there is nothing preventing it from being oversheeted.

Alex W 02-01-2014 10:11 AM

Re: Closer to the wind question
 
What size is your genoa when completely unrolled?

If it is a typical 130-140% size then rolling up to 90% will have dramamtically bad effects on how close to the wind you can sail. The rolled up sail disturbs the airflow on the front section of the sail, the resulting sail shape has a very deep draft with the draft often too far back, and on most boats you also lose the use of telltales. All of these will reduce the pointing ability of the boat. I only partially roll in the sail if there is no other choice (always reefing my main first), and have recently added a second headsail to my inventory (100% and 135%) for use in higher winds. It is a little bit of a pain to change a roller furling headsail, but it is great to retain pointing ability in higher winds.

How are you measuring your wind angles? 20 degrees off of the apparent wind is quite close. I find the most useful tool to be looking at GPS tracks because that shows you where the boat is actually going (after leeway, current, etc) instead of what angle the boat is pointing.

Multihullgirl 02-01-2014 10:16 AM

Re: Closer to the wind question
 
A bit technical, but here's some Arvel Gentry:
http://ljjensen.net/Maritimt/A%20Rev...l%20Theory.pdf

Also consider reading Bethwaite's "High Performance Sailing", and Marchaj's books.

Takes time but the answers will be correct.

bobperry 02-01-2014 11:05 AM

Re: Closer to the wind question
 
From the photo it looks like he sails a mid 60's sloop and you suggest Gentry and Bethwaite? Funny. His next post will be about tuning his 505.


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