Sail flat, sail fast...

Greenheart

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...it's said by many capable dinghy racers, and it makes sense...an upright boat presents more sail and must develop more forward thrust...and a hull which is heeled in the water must present a less-than-ideal hydrodynamic profile.

I remember reading of a non-sailing observer commenting on a dinghy race, who remarked that all the boats at the front seemed to be mostly upright, while those at the back perpetually heeled. The uninformed observer wondered why the back-numbers chose to sail at such an angle of heel, when clearly it did them no good. :rolleyes:

I seem to remember (I may have read it thirty years ago, or possibly here last year) that the critical things to remember in a breeze are:

a) Get the sail as flat as possible to gain forward thrust, rather than let the sail 'bag' the wind and push sideways, causing heeling;

b) Don't worry about always filling the sail when it's really blowing - it may not seem efficient to have half of the area flapping, but as long as the sail is flat as possible, even half its area will give plenty of drive, and staying upright is most important;

c) Raise the centreboard slightly to reduce lateral resistance;

d) Rake the rig back to help spill wind - and to keep the centre of effort in line over the backed-up centreboard;

e) Get the traveller away from the centreline - because high pointing is less important than steady forward progress in boisterous conditions.


I can't remember if any or many of these apply to yachts as well as to dinghies. But if anyone knows other tips for staying upright when beating...feel free to share.

Please don't include "eat more pies" or similar suggestions. I'm supposed to be dieting, so smart solutions, rather than fatty ballast, are what I'll need. Thanks!
 
Personally I'm still at the stage of learning how much to dump the main when things are getting a bit exciting. It's a tricky balance to get it right, or maybe I'm just being a very slow learner. All your other points are, IMHO, pretty insignificant in comparison.
 
This may be a bit purist, but I think I read somewhere that a slight heel results in a slightly longer LWL so boosts theoretical hull speed? S'pose it depends on hull shape, but I was always led to believe that a bit of heel was good, too much was bad, so advice was reef early and don't sail as close to the wind as you can in order to keep boat speed up...

My sails are quite old, though, so it's probably academic.
 
Back in my Laser racing days my technique for going to windward was to crank the sail in tight, hike as far as I could then steer to keep the boat upright. It may not have been the perfect way to sail but, when there was enough wind it kept me at the front.
 
All your other points are, IMHO, pretty insignificant in comparison.

Thanks Rob, but I wasn't including releasing the main altogether. I mean, in a steady force 5, it's not a case of easing off in gusts...because even the least amount of wind can feel more than is useable. So I guess race-winners - and other sailors who aren't easily over-powered - must be tuning their rigs more astutely than I, as well as being more agile.

To me, nothing's nastier than the "all-or-nothing" situation when the slightest adjustment of the main either sets the sail feathering and flapping deafeningly, or pulling uncontrollably and laying the boat hard over. I suppose sail flatness is the key - the flatter the main is, the easier it is to capture controllable amounts of thrust from a strong breeze.
 
This may be a bit purist, but I think I read somewhere that a slight heel results in a slightly longer LWL so boosts theoretical hull speed? S'pose it depends on hull shape, but I was always led to believe that a bit of heel was good, too much was bad, so advice was reef early and don't sail as close to the wind as you can in order to keep boat speed up...

My sails are quite old, though, so it's probably academic.

If you have a hull shape like this then you will tend to live a large part of your life at at angle...

01Abeamfromaloft.jpg




If you have a hull shape like this

open-60-uk.jpg



then I would have said no but that looks to have reduced the wetted area a hell of a lot - Miss Caffari seems to like a bit of an angle of dangle too:

avivadee.jpg
 
If you heel a yacht over to leeward it should create hydrodynamic lift to windward ...... the windward side is flatter and the leeward fuller. Also, as above, with flatter bottomed designs .... the more heel the less the wetted surface area and hence less skin resistance .... which is good when you are moving at less than planing speed: to windward, or in light air. Laser sailors should all know this.
Obviously there is a trade off with aerodynamics with the rig and balance. If you need to balance the forces by using the rudder (lee helm) then you are braking the boat and causing added resistance.
The balance and setup will change dependent on the wind strength, the state of the sea, the hull design, etc, etc. Knowing what to do comes with practice and class racing ...... it's an art with no hard and fast rules. You need to know what is the dominant resistance at any particular time and work to reduce it while improving the motive force.
 
In light winds it's often necessary to heel the boat so that gravity pulls the sails into a foil shape, when the force of the wind is not enough to do so. This is especially true if you don't carry a set of light-wind sails. Harder to do in a heavy keelboat, but in the conditions where it would be necessary SWMBO will usually have already issued the order to start the engine.
 
Back in my Laser racing days my technique for going to windward was to crank the sail in tight, hike as far as I could then steer to keep the boat upright. It may not have been the perfect way to sail but, when there was enough wind it kept me at the front.

That used to be the case I used to sheet the main in & keep screwing up to windward & my current phantom has a cam cleat to hold the mainsheet
80% of Phantom sailors have ditched the cleat so that they are forced to play the main more
Current training for cadets etc ( & opinion in general) is to hold a more constant course & play the main rather than turning into the wind too much
There is no doubt that it is faster
 
That used to be the case I used to sheet the main in & keep screwing up to windward & my current phantom has a cam cleat to hold the mainsheet
80% of Phantom sailors have ditched the cleat so that they are forced to play the main more
Current training for cadets etc ( & opinion in general) is to hold a more constant course & play the main rather than turning into the wind too much
There is no doubt that it is faster

Until I raced my Phantom, I always used the cleat a fair bit. My Phantom never came with one forcing me to play the main and my results started to show. You have to be fit to continuously play the main and coordinate with hiking, but it is definitely quicker. Having said that the Phantom is not too bad heeled a bit as it has a great big chine (see my avatar) that digs in, useful when you are tired.
 
We have been racing a Wayfarer for some 20 yrs. I thought all you had to do was read the books and you would come 1st. The only way to sail fast in any class is to race and see what the front runners do.

With the variables of sea state, tide and wind it's one of the most complex sports going.

Sometimes we have been miles in front of a competitive fleet and most times in the middle and frankly even now we are not sure what we do when we get it right and what we are doing wrong when we are going badly.
 
This may be a bit purist, but I think I read somewhere that a slight heel results in a slightly longer LWL so boosts theoretical hull speed? S'pose it depends on hull shape,
Windermere 17 ft Class yachts use the extra LWL to gain speed. Over the 100 years they have tried everything (within the rules) but the fleet is always heeled over. It must work, for them.

Classboatrace_40.jpg


or so
Classboatrace_21.jpg



Classboatrace_42.jpg
 
Dinghies and keelboats are totally different. By the time I'd got to full loony survival mode in the Fireball (fairly similar to your Osprey) I'd have...

Max rake
More prebend
Rig tension dropped off 50lbs
Possibly shorter spreaders depending on crew weight
Strut free to move forwards
Crew flatwiring
Max cunno
Max kicker
Max outhaul
Board up 50%
Move back
Full jib cunno
Jib bars out and up
Stuff in the gusts if it's a real slammer
Ignore where the main is or how much it's flapping...just sail flat!

Obviously totally different offwind though!
 
Windermere 17 ft Class yachts use the extra LWL to gain speed. Over the 100 years they have tried everything (within the rules) but the fleet is always heeled over. It must work, for them.

Can I suggest its anything they thought they thought they could get away with. From my experience of racing the rules are used more like guides if you can find away to dodge them.
 
Thanks again for all comments. Great pictures, Lakey. :encouragement:

More prebend; Strut free to move forwards; Jib bars out and up; Stuff in the gusts if it's a real slammer.

Thanks Iain, but I must admit I don't understand all of these. Struts, jib-bars...are they conditional on the boat being a modern very high-performance one?

Reef. It's amazing how much faster you can go with less sail up.

Thanks JD, that was initially my thinking too, but I'm keen to understand how the best class-representatives deal with significantly more wind on the nose than is practically usable.

I've sewn a really deep reef into my less-good mainsail, though I haven't tried it yet. I'm hoping the much lower centre of gravity, halved mainsail area (plus, having a roller for rapid genoa furling) will tame the boat in a blow - but I remain fascinated by the ability of middle-weight crews to keep a dinghy flat and fast under full sail, when I'd be heeling to 50°.
 
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