Light Wind
Printed From: Yachts and Yachting Online
Category: General
Forum Name: Beginner questions
Forum Discription: Advice for those who are new to sailing
URL: http://www.yachtsandyachting.com/forum/forum_posts.asp?TID=4676
Printed Date: 25 Jun 25 at 6:53am
Software Version: Web Wiz Forums 9.665y - http://www.webwizforums.com
Topic: Light Wind
Posted By: JonnyW
Subject: Light Wind
Date Posted: 19 Sep 08 at 9:57pm
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In light wind I understand that the kicker should be loose but different sailors offer different opinions on outhaul adjustment should it be tight or should it be loose? |
Replies:
Posted By: JimC
Date Posted: 19 Sep 08 at 10:43pm
| It depends how very light the wind is, and also how your sail is cut. If the wind is really really light it won't manage to get round a full sail properly so you try and flatten it off a bit, but that's sub flag flapping coditions really. |
Posted By: feva sailor
Date Posted: 20 Sep 08 at 3:19pm
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in light winds ihave the outhaul and downhaul on tight to flatten the sail compleatley.
also if its boring ligt winds i do stuff like walking around the forestay and so on
did it on the feva today, got the bow right at the water level and the transom like a ft off the water it actually worked quite well but heel it and it turns.
in general, if its light winds make it as easy as possible for the ind to flow over the sails. (ie, no bumps and an open leech) |
Posted By: redback
Date Posted: 20 Sep 08 at 5:03pm
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Just a little note for beginners. The pressure
developed by the sails is approximately to the square of the wind speed. So the difference between light and just a little more can be enormous. For instance 3knots is a drift but 6knots is 4 times as much power and so the sail setting would ideally be completely different. The trouble is when its light its also very variable so you are not going to be able to adjust for perfection and even if you could you'd gain a lot more by looking out of the boat and picking a good shift. |
Posted By: Lukepiewalker
Date Posted: 23 Sep 08 at 7:01am
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Depends if the water is flat or lumpy as well, generally would ease it a bit if lumpy, crack it in if flat. Wouldn't have the downhaul on at all myself.
------------- Ex-Finn GBR533 "Pie Hard" Ex-National 12 3253 "Seawitch" Ex-National 12 2961 "Curved Air" Ex-Mirror 59096 "Voodoo Chile" |
Posted By: feva sailor
Date Posted: 23 Sep 08 at 3:57pm
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with the downhaul/cunningam they say to pull on it gradually.
in medium winds (when the crew and helm is sitting but not hicking much) id have it lose.
in heavy winds back on again |
Posted By: tmoore
Date Posted: 23 Sep 08 at 5:20pm
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for the outhaul, the flatter the water the tighter i pull it on. never to the stage where you get creases along the foot of the sail (except in traditional classes with bolt ropes along the booms). in the rougher stuff if im underpowered then i can let the outhaul off so its up to 4/5" off at the deepest point. i tried loads of downhaul in light in the 300 and it puts huge creses running down the luff of the sail which made it really hard to read. i then let some off, pulled on a little kicker and let the downhaul slightly less until the creases down the luff just went. this seemed fast but i couldnt compare it to other 300 so hard to say for sure. this may be one of the things which only really works in the 300 as its a boat where normal sailing techniques often dont work. ------------- Landlocked in Africa RS300 - 410 Firefly F517 - Nutshell Micro Magic RC yacht - Eclipse |
Posted By: JonnyW
Date Posted: 26 Sep 08 at 2:31pm
| thanks all will try the suggestions |
Posted By: KennyR
Date Posted: 26 Sep 08 at 2:51pm
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Depends on the boat.
Two sails. Tight outhaul almost all the time, maybe off an inch or so in the lumpy stuff if you are underpowered. Ease it any more with the boom on the centerline and the leech points up to windward and acts as an air brake. Not fast. Easing it a bit gives more weather helm to give the rudder lift and some feel, but be carefull. One sail is completely different. To start with the sail needs to be thought of as a jib and not a mainsail. Hence the basic shape is different because of that with the draft much further aft than on a two-sail boat's mainsail. Therefore you need to sheet down 10degrees or so from the centerline i.e boom end over quarter roughly - Look at the way a laser or finn sails upwind. This means the outhaul can be eased a lot more before the leech hooks up to windward as it has to 'hook' by 10 degrees or so just to reach parallell with the centerline of the boat. In some cases this ease will be several inches with quite a 'bag' in the lower half of the sail. Whilst sail cut also has an effect, you can usefully use a lot more outhaul off on a singlehander. Quite common in Finns to use the outhaul as the primary 'power' control once the boomis on the deck. |
Posted By: jeffers
Date Posted: 29 Sep 08 at 6:43pm
Exactly....let us know what class you are sailing and better targetted advice will be forthcoming. I have sailed a variety of classes and they all vary. The Laser for isntance needs a little bit when it is light, the Blaze you just didn't use the kicker until you were stupidly over powered. The 8.1 you need a fair bit at all times to match the mast to the luff curve. The other (perhaps more important control) in the light is the Outhaul. A lot of people think the lighter it is the less you should use. Not so! In light winds you need to make the path for the flow as easy as possible to prevent it from becoming detached from the sail (not fast or efficient). In medium airs when are are searching for power you want to loosen the outhaul off so the wind is deflected the maximum amount (this helps generate power) whilst keep the flow attached. In heavy airs you want to reduce the power so it is back to tightening up the outhaul to help depower the sail (in conjunction with judicious ammounts of cunninham to open the top or 4th corner which is somewhere near the top batten on most sails). It is all about phyiscs, take a little time to understand what is happening to the air as it flows over the sail (you do not need to be an aerodynamicist) and the whole idea of what you need to do becomes a lot clearer and easier to understand. Putting that all in to practice however it an entirely different matter and takes time on the water and help from more experienced people/instructors. Just my 2p as always, i am sure someone will explode my outhaul reasonings somewhere along the lines! ------------- Paul ---------------------- D-Zero GBR 74 |
Posted By: G.R.F.
Date Posted: 29 Sep 08 at 9:33pm
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The trick in light airs, which I've also found true on dinghies, is to heel the
boat to leeward just enough to ensure gravity assists the sails natural curve, this also, depending on the particular boat hull and rocker, may naturally point the boat to weather, but this should be avoided, it is often better particularly in drifters, to keep moving by sailing a tad freerer to ensure a ready supply of created wind to make up for the lack of true wind in the lulls. Rigging the sail with not too full a draft, certainly not to tight or hooked a leech and as fine an entry as possible will all contribute positively as will keeping a weather eye open on the water as to where the damn wind is anyway 
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Posted By: JonnyW
Date Posted: 03 Oct 08 at 8:17pm
| Sailing a Merlin |
Posted By: RyanV49er
Date Posted: 06 Oct 08 at 5:43pm
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Sailing heeled only works in very light winds. After about 3 knots it starts making you drift sideways, so when you get the power in the sails to keep them filling when flat, keep her upright, bow down, don't hook the leech, open the slot and get your crews head out of the boat to find those gusts.
------------- Online sailing: For when you just can't get to the club: http://visser49erracing.wordpress.com/2009/10/20/online-sailing/ - Visser49erracing |
Posted By: redback
Date Posted: 11 Oct 08 at 11:15pm
| And at 3 knots its enough wind to power up the rig with full sails. Incidentally if its less than 5 knots you should be in the bar. |
Posted By: Lukepiewalker
Date Posted: 12 Oct 08 at 5:06am
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Clearly not a small pond sailor then. Most of my sailing career has been in less than 5 knots.
------------- Ex-Finn GBR533 "Pie Hard" Ex-National 12 3253 "Seawitch" Ex-National 12 2961 "Curved Air" Ex-Mirror 59096 "Voodoo Chile" |
Posted By: RyanV49er
Date Posted: 12 Oct 08 at 9:52am
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That's how I started out, on inland lakes. But you can't really learn anything if the breeze is always light so I've had to get to southampton (from oxford) every weekend for the last 6 years.. I'd hate to think how many miles I've racked up doing that every weekend. ------------- Online sailing: For when you just can't get to the club: http://visser49erracing.wordpress.com/2009/10/20/online-sailing/ - Visser49erracing |
Posted By: FreshScum
Date Posted: 12 Oct 08 at 9:59am
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A mode changes should occur when the wind flow switches from being laminar to turbulent. This happens at around 4knots depending on other factors such as humidity, air density, pressure etc. The sail shapes required for these two separate conditions are very different. |
Posted By: Lukepiewalker
Date Posted: 12 Oct 08 at 10:35am
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Oh you can learn lots, mostly about concentration...
------------- Ex-Finn GBR533 "Pie Hard" Ex-National 12 3253 "Seawitch" Ex-National 12 2961 "Curved Air" Ex-Mirror 59096 "Voodoo Chile" |
Posted By: radixon
Date Posted: 12 Oct 08 at 6:21pm
I dont have enough concentration for light wind sailing, but at the moment if I dont go out the liklyhood of a sail is nil ------------- |
Posted By: G.R.F.
Date Posted: 12 Oct 08 at 8:11pm
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Had another drifter today then having drifted out to the line, they very
sensibly abandoned. As to the sailing heeled point, which also worked well for us on the RS500, it heels your plate which gives a semi-foiling effect, we used to use it well on round boards, 'back in the day'. Flat isn't always fast, despite what you might read in the sailing books, it also, again depending on the particular hull shape reduces wetted area. |
Posted By: alstorer
Date Posted: 12 Oct 08 at 10:36pm
Indeed, but again depending upon the hull shape, heel creates turning motion which has to be c**tered either by slightly off sail trim (jib in a bit too far/main out a bit) or by using a little rudder. Which is, of course, why there's an art to the game. If it was all simple, we'd all be rockstars. |
Posted By: redback
Date Posted: 15 Oct 08 at 12:22am
| I don't think its the hull shape which has much effect. If you think about the centre of effort and the centre of resistance you'll suddenly realise that when you heel the boat you introduce quite an offset. No wonder the boat heads up when heeled to leeward! But in light winds that bit of weather-helm it produces can be an advantage and the increase in wavemaking resistance is slight. |
Posted By: NickA
Date Posted: 23 Oct 08 at 11:17pm
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Ideal light wind heel is totally hull shape dependant. On some hulls (eg the laser, the laser 2 and the 3000) you can gain in the light by heeling the boat by about 5 degrees and putting lots of weight forwards. Sort of "nose down and heeled". The under water hull shape is then narrow and points diagonally across the boat from the leeward quarter to the bows without causing much unwanted steering - though the boat should crab to windward a bit. I think the key thing is to accompany the heel with pushing the nose down. Think it works on a merlin too. Try it, report back! ------------- Javelin 558 Contender 2574 |
Posted By: G.R.F.
Date Posted: 24 Oct 08 at 9:50am
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If it's anything like round boards, which it undoubtedly is, it's about
balance. Enough nose down to reduce the 'swirl' of the stern but not so much as to introduce more wetted area of resistance than you have relieved yourself of at the back works well. Boats/Boards that are narrower at the nose introduce water line length with reduced surface area which is why it works. Examples of boat that are very difficult to do anything with in the light stuff like the L3000 with it's flat grabby bottom and shallow stern rocker that even with the crew sat right on the nose, it barely lifts the stern and heeling achieves not a lot except to help the sail shape. I should imagine that a merlin rocket would react well to the technique described, it has a fine entry and rounded bottom, looks one hell of a pointer, at least the one I saw did, do they vary from boat to boat, are some 'clinker built' and others not, are their rigs 'open' in design/sail size shape? Are they not 'river' boats, they must be good low wind performers. I bet if it's a drifter they'll be heeling them, then at the very quietest moment when everyone's concentrating their hardest, that guy with the General Lee will hit the horn.. 
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Posted By: tgruitt
Date Posted: 24 Oct 08 at 10:41am
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Yes they are great light wind boats, but quick to their handicap in any wind really. They are all 'clinker' as this is in the rules. I think the rigs have some openness about them, but the most efficient set up and sail size/ratio seems to be what everyone is going for at the moment, so there isn't much difference at all. Merlin sailors, please feel free to correct me...
------------- Needs to sail more... |
Posted By: Chew my RS
Date Posted: 24 Oct 08 at 10:57am
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Whilst the rig rules are fairly open, they all have the same sail shape because that shape gives the most area within the allowable measurement limits. So the sail shape is not really dictated by efficiency, but rather, by the rules. They are very beautiful and well refined boats, but not cheap (or light). ------------- http://www.sailns14.org - http://www.sailns14.org - The ultimate family raceboat now available in the UK |
Posted By: NickA
Date Posted: 24 Oct 08 at 2:27pm
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Tipping a V 3000 over 5 degrees works a treat - but you do have to get it at the point of heel at which it is least stable. Ie where it's narrowest. Also gives you the opportunity of hooching it back upright again when the wind reappears Think GRFs old purple monster was probably so heavy nothing would reduce it's wetted area short of filling it with helium!!! Merlins = handicap bandits supreme, and do those things POINT.. ------------- Javelin 558 Contender 2574 |