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de-powering the sail with a knife


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Being a flyweight is a great advantage in light winds, as I have less inertia, less drag through less submersed volume and can fly a hull in less winds.

In winds over 15 knots I get slower and slower upwind, as I have reached the limit to which I can counter-balance the sails force, so forwards drive is limited while drag continues to increase with wind strength.

At Kembla where the wind ranged 15 to 30 knots I came a predictable last. Heavier guys simply have more power to drive them upwind. After 2 long days of hiking out and working the main, I was sore all over, with hands burning from the rope work, but proud of being the only one to finish all races. Then furious with a comment along the lines of "if you were a GOOD sailor you'd do well in all wind conditions'.

Murray Jones of the Alinghi 5 sailing programme says:

"In a multihull the sail area is particularly critical; how much sail you should carry, because you want enough sail area that you can fly the hull and then once you're flying freely all the time, you don't really want any more because depowering usually increases drag. It's a matter of trying to learn how much sail area is the correct amount for different wind strengths."


All this raises the question; should I consider a 3/4 size sail for use in strong winds?

I have my old Williams sail spare, and as it has damaged bolt rope and boom rope, it's not too much of a loss to shorten it.

Any thoughts?

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G'day Tony,

Definitely DON'T take to it with a knife!

While I didn't hear the comment that infuriated you, I would consider looking at it from another angle. What they were probably trying to say was that there have been a number of very light PT sailors over the years who have been competitive across a very wide range of conditions.

While I'm no expert, there are a number of things that can be done to ensure the boat is de-powered and driving forward as much as possible, rather than being blown sideways. Things to try are:

- TRAVELLER: Drop the traveller out further. I have found that the boat can be rearing up on its ear at one setting and letting it out even an inch or two can make a lot of difference. On the first beat in the afternoon race at Kembla, I had my traveller out at the foot-strap. I realise everyone's straps are in different positions, so I measured mine for you. The centre of my strap is 380mm from the centreline of the boat.

- MAINSHEET: In combination with a dropped out traveller, tighten the main more. This really flattens the leech and drives the boom forward to de-power the lower half. It can be against your natural inclination to have a very tight mainsheet in a blow, but it is definitely the way to go.

- DOWNHAUL: You can keep pulling this to further de-power by flattening the sail and pulling the draft forward. Make sure your system is low-friction and has enough purchase.

- OUTHAUL: Tightening the outhaul will flatten the bottom third of the sail.

- LOWER FORESTAY: This is another great weapon in a Paper Tiger. Tightening the front lowers flattens the sail and keeps it flat even when you have to ease the main in a big gust, so this can make it more controllable in the puffs. Be careful not to over-do it. If you have a really good system, you need to ensure you don't go too far.

- STEERING: The most difficult part is learning to effectively steer the thing through the gusts for maximum speed while trying to avoid too much power in the sail. With good use of the systems above to have a very de-powered sail, you'll find you have a narrower "band" than usual, so will need to concentrate more to keep the boat on track.

I hope this is helpful. I can certainly put you in touch with a couple of lighter guys who may be able to provide some additional tips if you like.

But I certainly advise against cutting the sail down. I know you are probably one of the lightest PT sailors around, but you can still be competitive in the strong stuff with practice and good use of the controls. Don't expect to be able to win all the big blows, but you could rightly expect to be able to manage top ten and maybe even top six in the strong races if you learn to master the boat in those conditions.

By the way, well done on finishing all the races at the Kembla Klassic. Great achievement. And that kind of practice can only be beneficial.



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Thanks for that Dave, but I'm still not convinced. To drive the boat upwind requires the sail to curve the wind and produce a forwards force component. The heavier the weight used to counterbalance the overturning moment, there is proportionally increased forwards drive. I can maximise my righting moment by hiking out further, but the bruises and rashes on the backs of my legs are only just healed after that effort now 10 days later. Not sure I can increase my efforts there!

Sure there are lots of things I could have done better at Kembla, such as not getting into irons during tacks, picking windshifts better, avoiding other boats, and maybe easing the vang to run downwind faster without cartwheeling.

Going to windward I was pointing a bit lower than all the other Tigers, but moving at similar speeds. Downhaul, lower-forestays and outhaul were all on hard, with vang pulled block-to-block to limit mast rotation.

A few times waves/wind/spray coming over the tramp knocked the rope out of the cleat on the boom and let the outhaul off, but as the boat slowed noticeable when this happened I'd pull it back tight.

I'd have the mainsheet in hard in lulls, but either:

- have to round up to windward and come to a near stop in gusts, or;

- as I did; let the mainsheet go for a second and then haul it back in again as the gusts eased.

What are you suggesting there?

What about mast rotation? In the lighter wind (15knots) I was pacing 'Mojo' and had a good look at his setup; Ian seemed to have a lot more rotation than I'd ever use. Doesn't this effectively make the sail fuller?

If I loosened my lower rear stays, it could allow the mast to bend more and flatten the sail further, but wouldn't this cause a permanent bend?

A smaller sail set lower on the mast must be more efficient in strong winds. It seems as obvious as Lasers using the smaller Radial sail, as windsurfers having a range of smaller sails, or yachts changing sails for the conditions. Has no-one tried this on PTs before?

cheers, Tony

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Hi Tony,

You are in the same situation as I was about 3-5 years ago until I put on another 10 kg's.

I'm still lighter than most in KoBSC, and yes I cannot keep up with Dave and Wayne and others in the heavier weather - 15+ knots.

When the wind gets heavier this is usually what I do:

Vang - usually leave this at 45 degrees - ie: so the spanner points towards the front edge of the leeward centreboad case. Yes in the lighter weather, with a Redhead sail, this can be let out even further.

Traveller - this will be out a fair way - for me the towstraps are reference about 40cm from the middle. In 18knots that's where I set it.

Downhaul - I don't usually touch this at all. If at all, will only pull on about 2 inches.

Outhaul - to the max in 18+ knots.

Lower forestay - This is usually on fairly tight. I usually use this as a easy depowering/powering as it is the easiest to get access to while hiking out.

Rememeber all these settings are variable, and you will just have to work out the best setting for your boat.

One person told me that you could have the traveller out about 20-30cms but don't pull the mainsheet as tight as this will open up the leach at the top and depowers the top 1/2 of the sail. It works for me.

Anything you do you will not be able to point as high, but you should have a bit more speed and be more comfortable to sail than pointing high and just going up and down over the waves.

I don't adjust the rear lowers to the wind conditions. If you set them to they touch the rear uppers to somewhere 80-100cm from deck on both sides should work.

Easing the mainsheet is faster in gusts than pointing up.

I hope all this helps. These are my experiences.

David Anderson when he was much younger, he had a 2/3-3/4 sail which worked for him, but it is alot slower than a full sail.

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Cool, thanks 4 that. Is that David Anderson of Bryan & Peter Anderson family?

By the way Paul who is thinking of buying a PT said how impressed he was with how helpful and supportive all the PT guys he spoke have been. It's helped firm his interest in the class.

I'll be trying to encourage him when he test sails my boat, and will NOT tell him how much better he'll be once he learns how to be a good sailor; like other nameless wankers who can win a race in any wind on any boat even if the mast is bent and the rudders fall off. Pfft! Tell 'em they're dreamin.

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G'day Tony,

A couple of other things I forgot to mention were:

WIND SPEED: The afternoon race at the Kembla Klassic was supposed to be 25 gusting to 28 (that's what one of the officials told me). As the Paper Tiger class has an upper limit of 22 knots, we rarely face the conditions experienced at Kembla. There are various interpretations of the "22 knots", such as 22, gusting to 25, but most races at official PT events won't be run once it gets up over 22 knots. So it may be a bit extreme to modify a sail based on conditions you will rarely experience. As you are only allowed to measure one sail at a Nationals (unless you damage it), you wouldn't want to be using an undersized one.

BATTENED HIKING PANTS: I use wetsuit shorts that have built-in battens. While these can be expensive (although there are cheaper versions), they can be home-made. Ralph Skea made his own and apparently they work quite well. The idea behind battened shorts is that your thighs are far better supported by the long battens as they have a large area of contact/pressure, as opposed to without them, the contact is the narrow gunwale and this is far more painful. I am impressed with how much easier it is to sustain effective hiking using battened shorts.

Yes, the sail does require curve to drive forwards, but when it's pushing less weight, it doesn't need as much curve.

Despite what Neil says, it's not weight alone that dictates performance in strong winds. I don't believe Neil's lighter weight has anything to do with him not winning in stronger winds. When Ben Deed was a good 12kg lighter than me he would usually beat me in strong winds. Drew Helmore was another lightweight who did very well whenever it blew. To me, one of the standouts was Greg Cann. He won the first Nationals I sailed in a 75 boat fleet in a series that was generally very windy. And he was lighter than both Ben and Drew. While he didn't necessarily win every heavy race, he was up there all the time.

In regard to easing the vang when sailing off the wind, you need to be careful, as this will allow the top of the mast to lay forward in the gusts, which can be a risk to the mast. My approach to sailing downwind in a blow is to keep the vang on to protect the top of the mast. If I am broad-reaching and the wind is strong enough that I am fairly likely to bury the bow, I sail higher to the point where it won't be too likely to bury. Then, when I reach the point where I am directly to windward of the mark, I bear away and run square. While the bearing away takes a lot of care, if you pick your moment, it is fairly safe. While running (either on the dead run or after bearing away, as above), if I find it is so windy that I am likely to bury the bows, I actually pull the sail in a bit. This does two things. It presents less sail to the wind, so actually eases the pressure, but it also protects the top of the mast more as the mainsheet is providing a bit of tension on the leech, meaning the mast tip can't bend over the front as much. You just need to be careful to not pull it in enough to allow it to gybe accidentally and you have to watch it more carefully to avoid this.

Yes, David Anderson is the younger brother of Bryan. However, the cut-down sail was used by him as a kid so that he could go out safely, even in light to moderate conditions. Once his boat-handling improved, they put a full-size sail up.

I certainly should have been clearer in regard to the use of the mainsheet. Yes, easing it in gusts will still be necessary, however tightening it again rather than leaving it eased is important to maintain the flat sail and forward drive. As Neil says, easing and re-sheeting is usually faster than pointing up, but a little squeezing up is good for a rest if adjusting the sheet is wearing you out.

With rotation, excessive rotation can actually give you a flatter sail, as it allows the mast to bend more in the middle, which flattens the middle of the sail. This is because the boom is pushing against the mast's narrow section, allowing more bend than if there was less rotation (where it would be pushing against the deeper section.

Yes, lowers can be loosened to allow the mast to bend more. Class rules prevent you from changing this setting during a race, so you can get caught out if the wind drops. As mentioned above, PTs rarely sail in such strong conditions, so adopting a setting that suits the main wind range is ideal. Some people tighten their upper rear stays in a blow to provide additional support for the mast.

While Lasers do have a smaller Radial sail, you rarely see someone who alternates between the two. The Radial Laser is a class in its own right and people that race them use only the Radial sail.

I'll leave the final word to a guy who was a much better PT sailor than me, Kim Faihall. Kim was a former International and three-time National Champion in PTs. He wrote and article for the 1997 PT Tuning Manual about sailing in moderate to strong conditions. Here is what he wrote about body weight:

"Skippers body weight is an upwind performance factor in strong breezes. Typically, skippers in excess of 80kg will perform better in the 16 knot and over range but below this wind speed these skippers will be disadvantaged simply because they cannot derive enough power from the sail despite its trim. However, such a disadvantage can be compensated for by minimising tactical errors and concentrating on maintenance of boat speed and boat handling. Interestingly, low mass skippers (that is those below 70kg), are not proportionately disadvantaged in higher wind strengths since sail shape may be sufficiently altered to reduce available power. Once again however, the performance of lower mass skippers in moderate to heavy breezes is also contingent on superb boat handling and sail trimming skills. An Interdominions heat sailed in the Tasman Sea off New Plymouth, NZ highlighted to me that light skippers can do exceptionally well in heavy conditions. In approximately 20 knots of breeze, in very big seas and on a course which took over 2 hours to complete, Greg Cann finished second in a race which supposedly was a heavyweight’s dream. Through depowered sail trim, sustained and efficient hiking and excellent tactical decisions Greg was able to put some of the heavyweight flyers to shame. He eventually went on to win the Interdominion Title.

Consequently, what is important in maximising the performance of a PT in moderate to heavy conditions is not body mass but how a skipper matches sail trim, boat handling and hiking performance to the prevalent conditions. Body weight, while conferring some advantage for some skippers in some conditions is only a minor factor in overall regatta performance where typically a variety of conditions will be incurred. However, if you are a heavier skipper you should always aim to capitalise on stronger wind conditions whenever they prevail."(Kim Faihall)



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There's three topics going on here

- should I try a 3/4 sail?

- tips for heavy winds

- dont talk to people like they're beginners!

A 3/4 sail:


On the first, the example of Laser Radial is that light skippers choose and stick with the smaller sail, as it's more appropriate for them. Yachts select smaller sails in strong winds because they are more efficient that a big one flattened and blown out.

As I'm around 20kg lighter than most PT skippers, this is a massive, noticeable difference in strong winds. Your example Ben Deed, 68kg in 2004 when finishing 3rd at nats, still has 11 kg on me. Weight from: http://aptca.papertigercatamaran.org/top_ten_gear.htm

Cant find stats on the other guys.

Obviously you haven't experienced what I'm talking about. If the typical skipper has 40% more than my weight, try sailing in 40% more wind; say 30 to 40 knots, and experience what it's like for me. Want a smaller sail yet?

In winds upto 15 knots I can trim the sail and fly around the course. Speed lost to windward is made up for by faster acceleration & speed on reaches and runs. In winds above that, the loss of power compared to heavy skippers is obvious. As I said, I become slower and slower in increased wind due to increased drag with no gain in power. It's physics not skill; 40% heavier skipper = substantially more power!

It's series like Kembla where strong winds are forecast for the entire event that I'm thinking of a 3/4 sail. Thanks for the debate; it's convince me I'd go faster & enjoy it more with a smaller sail. If I cut down my old Williams sail, it will at least get used occasionally instead of living in the cupboard.

Tips for heavy winds:


With superb boat handling and tactics I could compensate for the difference; are you talking about PT sailors? The ones I race against don't make that many mistakes.

Thanks for all the tips; you confirm that I've been trimming the sail and handling the boat correctly. 20 years experience in a range of dinghys has paid off.

dont talk to people like they're beginners:


Great that PT sailors freely give help and advice, supporting each other and developing the skill level in the class.

Not great to persist in assuming that if someone comes last they must be a hopeless beginner. That's rude and discouraging.

Maybe sledging has a part in sport, but not in my world. But if I were good at team sports, I'd play cricket! Solo sailing, bring it on.

So great to hit the water yesterday in 15-20 knots and fly around the course. Speed! Acceleration! Power! Yeah and it felt good to be fastest on the lake and win by over a lap against a heavy skipper. (head swells)

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If I am reading your reply correctly, it seems I have offended you. If that's the case, then sorry Tony. That was the LAST thing I intended to do. I actually put a lot of time and effort into those responses because I know you are so enthusiastic and fired-up about your sailing.

I was trying, to the best of my ability, to answer the questions you have been asking.

While I am far from the best PT sailor around, I thought my advice was sound and I thought I was providing you with plenty of information. I never once assumed you didn't know any of it. I was just making sure I had covered what I considered were all the aspects in case you maybe didn't know one or two of them.

I can't recall ever being criticised about talking to someone like they were a beginner for providing advice. Once again, my apologies if I came across like I was talking this way. It was certainly not my intention. I know you are not a beginner.

If my comments about Neil were considered offensive, I apologise. I was stirring him up and told him so before I read your reply. Neil and I are good friends. I still believe he could beat me in strong stuff if he wasn't phased by the heavy conditions. He beat me three times out of three races in moderate stuff yesterday.

A couple more points that again are not intended to offend:

- Greg Cann (who I mentioned) was about 5 or 6kg heavier than you, so a close comparison.

- The tips from Kim Fairhall that refered to mistakes of others were not my words, but Kim's.

As always, I hope to be able to provide continued assistance and advice into the future.



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Agree you've provided excellent tips and advice, that anyone browsing this forum might learn from. Thanks and well done especially for the 'help and advice' section at: http://www.papertigercatamaran.org/

Regards tips on de-powering / trimming sails; the old PT Tuning Manual has sections on Williams/Goodall, Gale and Rimmington and Irwin sails. Howabout a similar piece on tuning the radial Redhead? Ian?

Hopefully will borrow a PT to race you this Saturday at Koonawarra & we can talk about it all over a beer after. Cheers

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Keep your full-size sail Tony..

I'm pretty sure i've experienced what you are talking about where the boat feels totally overpowered and out of control!

PT sailors are a pretty helpful lot, and i got the same tips on depowering as Dave has been trying to get across. I was fortunate to buy a boat that was very well set-up, and so i knew the problem was with my technique. The guy i bought the boat from showed me where he used to run the settings (this was a Goodall cross-cut). I was dumbfounded, the downhaul was WAY tighter than i was using, to get the settings i had to literally put my feet on the front beam and pull with all my weight... Also the mainsheet was very tight. On the beach the sail looks completely flat, with the top 3 battens pulled inside-out.

The other thing is trying to reduce leeway upwind in a strong breeze. You need to almost be shy reaching around the course, the lighter you are, the lower you need to go. It's interesting to look from behind (my usual position in a good fleet) and see boats with their bows pointing lower than others, but tracking at a closer angle to the mark as they are making less leeway.

Just for laughs, try this when you get your next really windy day, don't even focus on trying to point high, just start out with the traveller halfway in from the edge of the boat to the centre, then slowly pull the traveller in until the boat feels overpowered, ease it a fraction and sail upwind on that angle. It's more fun, and you'll find you get there faster anyway!

When it's really windy, i haul all the ropes on really tight except the front lowers which are on firm, and don't change any of the settings as i go around the course.

And i've sailed Tigers from when i was 55kgs through to when i was 95kgs, the lighter you are the easier it is to run at the front.

As for talking to people like they are beginners, i've been sailing PT's for 22years, and still need my information delivered in beginners language, i doubt anyone is trying to be patronising towards you, they are just making allowances for people like me!


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"Paper Tiger"; one who appears powerful but is actually powerless and ineffectual. Grrrr

In strong winds bodyweight is like motor size. To get your 4 cylinder Commodore going faster than a V8 Supercar? You just have to tune it and learn how to drive... !

Paper Tigers are great in that people of a range of body weights can sail them, and the sail is adjustable enough to allow the range of skippers to compete on fairly equal terms, in normal conditions.

At Kembla I had the sail trimmed flat, traveller out, pointed lower than everyone else, and was just way overpowered in 20 to 30 knot winds. At times going to windwards I've had to let the sail way out, like a broad reach, and was fully hiked with a hull flying just to balance the wind blowing on the mast, while slowing to a near stop as wind and waves tried to drive me backwards. The only way I could go downwind was pull the traveller in and keep the main tight, 'cause if I let it out the nose would just get driven into the water & she'd cartwheel. Dave made a good point about letting the vang off to allow the top of the sail to point forwards, which I'll try next time.

But cartwheel! Leaning back behind the transom, hulls planing with blinding spray shooting out & wind curling it over the deck, centreboard hum a high pitched whine, then a huge gust drives the nose in, the whole boat flys airborne, rudders skywards and I'm thrown to land near the top of the mast... all good fun. Give me a storm sail so I can go for it instead of using a survival strategy.

[This message has been edited by tonyquoll (edited 15 December 2009).]

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Hi Tony,

I've been watching this unfold, whilst I'm not a Paper Tiger sail and have never sailed one (yet), I do have alot of experience in 14ft Cats.

I'm not hear to say whether a 3/4 sail would be better/worse in heavy wind than a full sail. I will reiterate a point Dave made, which needs to be considered heavily before you invest time and money.

At regattas (pretty much all), state titles and national titles you are only allowed the use of 1 set of sails that measure in against class rules.

In the 17 years I've been sailing, it's rare to get a multi-day regatta where the breeze is constantly in the wind range that would make a 3/4 sail more effective.

If it's a Paper Tiger regatta say a states or a nationals your class rules have a max wind limit of 22knts. Whether its average or peak I'm not sure (most are average). It would be even more rare to get a regatta where you actually have a race run in the conditions that a 3/4 sail would be more effective.

It's a bit like the Tornado's at the Beijing Games in 2008. Some teams prior to Athens came up with the idea of using a VERY flat "spinnaker" which was basically a very light wind code zero able to be flown upwind.

Whilst it wasn't used in Athens, it reared it's head before Beijing with I think 3 teams trialling it and committing to it verbally. When it came to measure in the Dutch (Mitch Booth) & 1 other switched back to normal spinnakers, leaving the Americans in the false hope that they wouldnt be the only ones with it (it was a big gamble). The americans were pretty much out the back door the whole olympics because they measured the code zero spinnaker in anticipation that they would have less than 5 knots the whole regatta.

So using that as an example say you do all your heavy wind sailing with a 3/4 sail and then you go to nationals. The question is do you gamble and measure in with the 3/4 or a full. Knowing that if it blows the whole regatta your set, but if it doesn't you wont have the power the other sailors do thats needed in the light weather.

The flip side, you measure in a full sail and for the majority of the regatta its the right wind for that sail. But you get 2 heavy wind races, you've trained with a much reduced sail but now you have to adapt to big wind sailing with a full sail.

Does the paper tiger class allow reefing points? this would be a way to over come this, as it's still the one sail your just putting a reef in it.

Anyway, just the thoughts that would go through my head if I were to look at something similar.

Congrats on finishing all the Kembla races. I didn't compete in the Saturday arvo race (I went out but thought better of it half way to the start line).

My motivation for turning around? 3 weeks from traveling across the nullabor to Albany for nationals. If i broke something major, not only was it going to be expensive but the potential of getting the boat in shape to defend my title was limited. Bottom line the advantages for me staying on the beach out weighed the advantages of stay on the race course.

There was some serious wind out there (Steve Brewin said around the 30knts gusting over), so again hats off for getting around the course. One of only 2 14's i believe.

Keep up the sailing, it's always great to see someone so enthusiastic about their sport (particularly when its sailing!).

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Firsly, Tony, if you would like to try a smaller sail, I think we have some reeeeeaaaaaalllly old sails here at Koonawarra Bay that you could cut. I'll have to double check on Saturday about this, but it would be interesting to see how this would go.

Secondly, the amount of information on this page/topic is enourmous and will suit anyone who comes onto this forum to find info about light people and strong wind - almost good for an article of some sort.

I wish we got strongish winds here so I can get more practice in 15+ knot range.

We'll see what this Saturday brings smile.gif


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Thanks again for the sound advice, and also for offer of an old sail. No need; I've got a Williams, Lidguard or Harmony to choose from here. Both "Tigerdelic" and "Pelikinetic" are now flying Redheads, while we've kept old "Why Worry?" in classic 70's trim with an old Lidguard.

Similar to boats who DNF'd to avoid the risk of damage, I'd like to fly the storm sail instead of risking my nice radial Redhead sail. Most of my racing is at Wallagoot Lake, and they don’t care what sail I use, but want me to put on about 40kg so I'm on-par with the other guys. For at least the next year there’s only weekend regattas, including the State Titles, where I can choose one sail depending on forecasts and stick with it. All good. Even if I were at a week-long Titles series, I'd be tempted to fly the storm sail in a blow and enjoy a great race, get DSQ'd, rather than get blown back to last.

The only question remaining in my mind is how much to cut off the bottom? A standard sail is 9.29m square (100 square foot), with a luff of 6.1m, which suits me upto 15 knots. I want a sail for 15 – 25 knots. If we assume the sail is triangular, then the centre of effort is 1/3 the way up, and area = 1/2 foot x luff.

Overturning moment = wind pressure x area x height of centre,

= wind x ½ foot x luff x 1/3 luff,

= wind x foot x luff squared / 6.

If I cut the bottom off, then foot wont change much. Assuming wind pressure increasing in a linear relationship with wind speed, then how about

15knots x foot x luff squared / 6 = 25knots x foot x storm luff squared / 6

Simplify to storm luff = square root of (37.21 x 15 / 25) = 4.72m

Area (from counting squares on scale photo) = 7.24m

Sound right?

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Following is extracted from an email received by a Catsailor reader, that I thought worth sharing:

“The discussion on sailing in strong winds was interesting. To my mind there is no doubt that the weight of the skipper affects performance, both in light and heavy winds, and that your light weight is an advantage in very light winds, and a disadvantage in strong winds. In strong winds, for the same skill level, the heavier skipper will win.

I found it interesting to read how far out some of the Paper Tiger sailors had their traveller in a blow. While their other suggestions were more Tiger specific, the same general rules apply, so they were helpful to me too.

I suppose the only thing to do with a small sail is to try it. In terms of how big yours should be, I think that your size is about right, although my reasoning is a bit different. I would suggest designing it for 20 knots, rather than 25, since Paper Tigers have a limit of 22 knots. On the other hand I think the relationship of wind speed to pressure is fairly complex, it is a one to one relationship at low speed, but I think by 15 knots it would be approaching something more like pressure is proportional to wind speed squared. 25/15 = 1.67, while 20sqd/15sqd = 1.77, so there is not much difference.

Personally, I would prefer people treat me as a beginner more often! I find that because I am an obviously mature person, people are reluctant to give advice. I am a strong believer in listening to advice from anybody, beginner or expert, and regardless of whether they are condescending or admiring. It can be a bit irritating when somebody attributes some minor failure to deficiencies in me personally rather than to circumstances beyond my control, but such is life, you can't please everyone!”

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Was thinking the easiest way would be to cut the foot off the old Lidguard and sew it onto the Williams (as the tack & clew on Williams are stuffed).

Then I thought I could paint thinned out polyester resin on the rear 1/3 of the sail, to stiffen it. (Suggestion from discussion on restoring old sails at Sailing Anarchy). This might give the old cross-cut sail the sweet curve and properties of radial cut sails.

Then I checked the rules and got all confused:

"10.3 7 full length battens only"

- so there must be 7, or maximum of 7?

"10.10 Reef points may be fitted if desirable"

- If the sail had reefing points, then I could change to size to suit the wind, and have the multiple sizes allowed in all races?

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My interpretation of the batten rule would be that it cannot have less or more than 7 battens. Just by the fact that it says "7 battens ONLY" Not "a maximum of 7 battens".

But the reefing points rule is gold for you... it means no cut and shut of the main. Just get reefing eyelets put in and then when it blews like stink you can reduce the sail area legally.

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Awesome. Thanks for that!

Started a discussion on how to install a reefing system at:


I've looked at a few pics of reefing systems, such as the 'Dutchman System': http://www.myboatsgear.com/newsletter/dutchman.asp

but cant see how the outhaul & downhaul would work with that. Do you have the control systems on hooks, to re-attach to other eyelet after reefing?

Does the bolt rope on the luff have to be modified?

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I disagree with your theory that a smaller fuller sail will be more efficient than a larger flatter sail, especially upwind.

In my experience the top of the sail helps the leech of the bottom part of the sail open, and assists in the efficiency of the sail.

From heavy weather (30knot average) 2-boat tuning when developing my sail, looking from behind the top 1/3 of the sail is perfectly flat, and also in line with the apparent wind. It's only purpose is to support the leech of the lower part of the sail to create an efficient shape.

If you are talking about broad reach conditions, then i agree a smaller sail would be an advantage in not going for a swim.. My only remedy for that is to avoid a broad reach in those conditions.


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Thanks for feedback. Did you compare a smaller sail when 2 boat tuning?

My reasoning:

Drive is produced by bending the wind; requiring some curve. Drag results from wind flowing over surface.

Flat sail with no curve = all drag and no drive.

Smaller sail reduces drag, allows more curve and increases drive, overall increase in efficiency. Also lowers centre of effort, reducing over-turning moment.

Leech tension and sail twist would work in the same way, just on a smaller scale.

Interesting to see the Wild Oats and Alfa reef their mains after turning into the wind out of Sydney heads. It seemed to help them keep the sail in a nice shape instead of flapping around at the top.

Good luck at the Nationals everyone! Please post updates to this forum, would love to read how it goes.

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We didn't try a significantly smaller sail when tuning.

I never had a problem upwind in up to 30knots with a full size sail, and we were interested in making a competitive sail, so there wasn't much point testing in conditions stronger than that.

I'm thinking the drag of the wind passing over the surface of a sail isn't as significant as the cross-sectional area of a sail being presented to the apparent wind. I haven't got any data to back this up though?

The maxi's in the Sydney-Hobart certainly need to reef their sails, although if they could scale up a rig system similar to what is used on a PT they might think differently. Look at the mast bend on a land or ice yacht to get an example of what i mean by the top of the sail inducing an efficient twist into the leech of the lower part of a sail.

Not trying to knock your idea of making a smaller sail, often the best way of seeing if something works is to ignore the theory and just make it and see. That is what i have done with my sail and mast combination in any case.

I'll try to keep the nationals news updated on here throughout the regatta.

Cheers, Tom.

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Right. Aerodynamic drag = frontal area x drag coefficient.

Smaller sail = less frontal area, + lower drag where there is no sail anymore.

With my weight I can make effective use of the sail in winds upto 15knots, with noticable drop in performance above 20 knots.

Guys who weight 40% more are effective upto (15 x 140%=) 21knots, drop in performance noticed above 28 knots.

Tom your story of sailing in 30 knots suggests that you must weigh at least 85kg. Yes?

Youtube video of huge cat with massively reefed sail getting airborne on the ocean:

Imagine if they'd kept the full rig up; I bet much slower with big flat sail flapping around and no drive.

All of you who keep arguing that I just need to learn to sail will have NO RIGHT to complain about my unfair advantage when I start using an adjustable reefing system. OK?

[This message has been edited by tonyquoll (edited 28 December 2009).]

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  • 1 year later...

16 months after this thread started;

- gained 5kg in body weight and found it makes a huge difference to power upwind

- modified boat with longer boom to pull outhaul further, and loose lower rears allowing maximum mast bend; both contributing to flatter sail

- was able to pace heavier guys in 15knots, but lost ground to them in winds stronger than that

- hiking pads help sustain hiking out for long periods, but reduce dynamics (moving in and out quickly)

- noticed that traveller beyond footstraps and cranked mainsheet can still point high; by driving the leech it increases weather helm and the rudders help drive the boat to windwards

- easing the boom vang when going downwind in a blow definitely prevents cartwheeling; haven't flipped it since that weekend at Kembla '09.

I've noticed the fairy-tale stories about lightweights winning major events develop like Chinese whispers. The lightweights described may have actually weighed 65kg+, and the wind range 15-20knots in some races, with the winner being close enough to the heavyweights in those races, and winning the lighter wind races, to take an overall win. A better example is Alex Craig at this year's (Jan 2011) Nationals at Lauderdale. Although slightly lighter than most other skippers, he was able to point higher and go faster by dropping the traveller further and sheeting harder, plus perfect steering over the swells & chop. That doesn't mean a 55kg skipper can win races in 20+ knots by being a "good sailor"!

Sailing an NS14 at Twofold Bay Regatta, we had the disaster of the rig falling off after the adjustable sidestays were accidentally released. I thought I did well in getting the gear back on board and the mast up again; while the boat rolled around in 1m swells. Back on shore I was told about the guy who lost his rig over the side, rolled the boat upside down, re-stepped the mast and secured the stays, righted the boat with rig back on, and then went on to win the race! "But he was a GOOD SAILOR"....

Over the last season I've sailed a few other classes of boats, and a few other PTs, and come to realise my boat 2901 "Tigerdelic" is the most fun I can have on the water. Love it. Although my current sail is only a few seasons old and in great condition, dreaming of a new one to last the next 10 years or so:


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