Sailing upwind in Cat/sloop
I apologize in advance to the fellow who PM'd, me with this question but regretably my answer was too long for a PM. I thought this might have enough general interest that I put it here. Out of respect for their privacy the question has been altered so that hopefully the specific person and boat is not identified. I also apologize because much of my answer was copied from an earlier post that I had written for some other similar discussion in some other sailing forum.
The questions was: I have just purchased Canadian crusing design built between 1986-89 (not a Nonsuch), that is almost a catboat, with mast far forward, large main, fractional rig and a small jib that just fits between forestay and mast and which self-tacks. The boat is widebeamed and I've found it doesn't point that well. I'm getting 65 degrees tack angles. Is there anything I can do to the trimming or sail configurations (i.e oversized jibs, etc.) that might improve the upwind performance?
My response is that it is a little difficult to answer this question without knowing the boat and seeing how the person sails her. I am also not familiar with the specific model in question so I am guessing a bit and talking in perhaps broader generalities than might be ideal.
That said, this boat was not unique.The 1980's was a period when a lot of manufacturers hoped to cash in on the popularity of the Nonsuch. Manunfacturers as diverse as C&C, Freedom, Hunter, Herreschoff Catboats, and Pearson, built 30 foot or so catboats with freestanding, or nearly freestanding rigs, many of which also tried to add spinnakers or jibs.
In most respects, these were reasonably good boats in terms of nice accommodations, easy handling and reasonable performance. To one degree or another, a short coming of almost all of these catboats was some reduction in windward performance.
This shortcoming derived from a number of common causes that are imbedded in the design concept of many of this style of boat. First of all, most of these boats offered moderately shoal draft fin keels. While better for windward performance than a full keel, these long fins tended not to point especially high as compared to deeper draft/ shorter chord fin keels, plus they also make a lot of leeway.
Most of these boats had a lot of wetted surface. While part of the cleverness of the Nonesuch was that that Ellis had carefully modelled his hull form to minimize wetted surface, few of the clones seemed to be as careful. Lots of drag requires lots of power to overcome and so many of these boats had to be 'driven off' rather than pinched. In other words, om order to over come all of these design issues, these boats were typically sailed so that the helmsman does not try to point as high in order to optimize the speed part of the VMG equation.
Next comes the rig. Important to sailing upwind consistently well is maintaining good airflow over the sails. Freestanding rigs (which I assume your boat is and apologize if I am mistaken) have several inherent problems when it comes to beating. In a general sense, to make up for the lack of shrouds, they tend to have much larger diameter masts, and these tend to throw a big wind shadow. To a minor extent, the mass of turbulance being shred off these larger diameter masts is like sailing in bad air all the time. Some like the Freedoms had carbon fiber masts of a smaller diameter, but some used what were essentially heat hardened, spun aluminum light poles which were heavy and had a very large diameter.
Upwind, it is important to keep the sail shape steady as well. Because free standing spars tend to be by their very nature more flexible than stayed spars, there is a tendancy for the forestay tension to vary and with it the headstay sag to vary as well, this automatically changes the angle of attack and lead angle on the jib, disrupting the airfliow over the sail. Similarly, the head of the mast flexes as well, opening and closing the leech, loosening the halyard tension and flattening and rounding the sail with each cycle. Its disruptive to the sail shape and airflow, which are also bad things for upwind sailing.
Even so, tacking through 130 degrees is excessive. What makes matters worse is that I am assuming that this angle is being read off of the compass courses and not off the GPS and so does not include leeway.
Anyway, getting to the heart of your question. First of all, because of the large amount of wetted surface on these boat, if you want toi go up wind, a clean, smooth bottom paint is extremely important. Ironically more so than on a race boat.
I would then next start with the jib. First of all, the jib should have a row of telltales roughly 18 inches from the leading edge and there should be one set (one on erither side of the sail) that is roughly 25% from the top, 25% from the bottom and one last set in the middle. If you don't have them make them and put them on. These can be made with 8" lengths of yarn or musical cassette tape taped to the sail.
When going upwind I would spend time on the foredeck and watch the sail to see what it does. Have the helmsperson slowly turn up towards a luff and then fall off. The windward teletales should all start to act up at the same time. Tall blade type headsails are very sensative to sheet lead angle and self tacking jibs rarely have proper sheet leads. If the telltales at the head or the foot 'break' first then the sheet lead is wrong. Some of self tacking jib systems permit lead adjustment but most don't.
If you can adjust your lead and the head of the sail breaks first then the lead needs to be moved forward to pull downward and use more of the head of the sail. If the bottom of the sail breaks first then move the lead aft.
If you can't adjust the lead at the sheets, then you are stuck going with the traditional method of raising the tack of the jib above the deck with a pennant. If the windward head telltale of the sail is breaking first, then add a short length of line to raise the tack of the jib above the deck further. If the bottom is breaking first and there is no penant then the sail is probably shot.
If the jib is on a boom, there are no easy answers other than to get a sailmaker to look at the sail and see if it can be recut.
The next issue is the length of transverse motion of the jibsheet lead. If the motion is too wide, then you cannot point. You can look at ways of keeping the jib traveller from swinging as far.
While improving the Jib lead can help a lot, I am afraid that adding a genoa probably will not do you much good.
Then move onto you mainsail. The big issue here is getting a tight enough leech to point without stalling the sail. In this case, telltales in the trailing edge of the sail near the batten pockets can really help. Upwind, the outhaul halyard should be reasonably well tensioned. Ideally the traveler and mainsheet are set so that the boom is roughly on the center line of the boat, and the trailing edge of upper teletale is roughly parrallel to the boom (sight up the sail from below the boom.) The trailing edge Telltales should be flying and the sail should not be luffing. Too tight and the sail will stall, too loose and you can't point. Moving the traveler above the centerline and easing the sheet will allow the upper batten to open up if it is cocked to windward and dropping the traveller and tightening the sheet will move the batten to windward relative to the boom. Play with this and you should see both your speed and pointing angle improve.
Most of these catboats were sold as being easy to sail and so had primitive sail shaping gear so you are somewhat limited in what you can do beyond that. With good hardware you can often get good performance upwind even with old and blown out sails. But in the absense of good sail shaping gear, the sails take a real beating and there is nothing much you can do about it. This means that sails have a shorter lifespan on boats like these and they will have a bigger impact on upwind performance than on more conventionally rigged designs. In other words, if you really care about good upwind performance, you may need new sails. Uh! I hate being the one to say that.....
Pearson 303 upwind
Hello all from a novice sailor with a Pearson 303. I am trying to determine how close to the wind I can sail effectively and if there is anything I can do to improve it with trim or stay/shroud tensions. It seems that right now I can only get to within 60 degrees of the wind before a dramatic reduction in speed. For instance yesterday I was in a close reach making over 6 knots, as I headed up closer to the wind but before it luffed completely my speed reduced to 3 knots or so. This occurred when the apparent wind was a little less than 45 degrees off the wind.
Should I be measuring the sailable angle into the wind from just before it luffs but making little headway, or from a better angle with decent speed. Also is there a rule of thumb or formula of when to bear off to gain more speed. In other words if my destination is upwind, is it better to go closer to the wind slower or go further away from my destination faster?
The last thing is whether the rake of the mast has an effect on upwind angles. Mine is noticeably raked aft. Would straighter up improve upwind performance.
Neil, a boat like the 303 should be able to sail within about 45 degrees of the wind and only lose a bit of speed - no more than a knot. While rig tuning may be an issue, sail trim is more likely. The most important things include the position of your genoa car to control the genoa shape and the use of the traveller and mainsheet to control the main shape. Next comes things like halyard tension and outhaul tension. Telltales on the genny and main are essential to understand what is happening.
I have so much to learn. I have totally ignored the genoa car and the outhaul. The genoa as a result was quite full and rounded which I assume should be flat instead, like the main. I am going sailing for a week next week and will try it out. Thanks so much.
You cant change the shape of the hull; but, you CAN change the shape of the sails — to accomplish better pointing, faster sailing, more power, etc. etc. etc.
Pointing ability also includes proper SHAPE of the sails and proper shaping can be accomplished by the usage of tell-tales.
One of the *very best* series of articles ever written on tell-tales can be found at: ArvelGentry.com ----> magazine articles ---->
---> A sequential series of 4 articles:
Checking Trim on the Wind, November 1973
Achieving Proper Balance, December 1973
Sailing to Windward, January 1974
Are You at Optimum Trim?, March 1974
Before you start with the above, TUNE YOUR RIG FIRST, as a sailboat with a too loose forestay (tension controlled by the backstay) will NEVER be able to point well. Aim for 15%+ backstay tension for sailing in 12-15kts of wind, etc. There are many internet 'articles' on rig tuning but be aware that the only 'valid' rig tune articles will be based on NUMBERS of % of rig tension - Youll need tension gage or equivalent --- or a good rigger who also races sailboats.
The reason for this is that a sailmaker when designing a jib/genoa EXPECTS that the forestay will be about 15%+ tension and if the actual forestay tension is less than that, the foresail wont be able to take on the DESIGNED shape and you get: so-called 'weather helm', boat skidding off to leeward, s-l-o-w boat and boat that aggressively heels but cant point !!!!!!
Thanks Rich I will definitely read those articles. The backstay turnbuckle is at its maximum right now but I don't have a gauge to measure it. There is noticeable rake so I assume I am at the best I can do for that. The weather helm for the Pearson 303 is well documented and mine seems to fit in what others describe so I will concentrate on sail shape (new sails) and learning how to read the telltales.
Again thanks so much for the help.
The 303 usually has a woven dacron mainsail with a boltrope (3 strand dacron rope in a sleeve at the luff).
Most sailors dont 'raise' such sails properly .... you need to raise and THEN apply additional strain to the luff to additionally stretch-out that boltrope so that the sail can take its 'designed shape'. If you dont do this the poor shape will cause a LOT of 'weather helm'.
Next time out, raise the main and then apply additional halyard tension by 1" for every 11 ft. of luff length (about an extra 3" for a P303).
Then, Put the boat onto a hard beat at 12-15kts and let go of the wheel. If the boat keeps a straight course or falls off to leeward ... then slightly ease the halyard until the boat 'slowly' heads up to weather. If the boat 'heads up' aggressively, add more main halyard tension and/or THEN consider to take some rake out of the mast.
A boat that is dragging its rudder sideways through the water isnt going to 'point' (may be skidding off to leeward) and is going to be 'cranky', etc.
The 303 has DEEP bilges and not much relative exposed keel surface area. If you heel a lot .... that keel is going to start to slip to leeward. Usually better to keep such a boat 'standing more upright' when beating. Watch how the wake is coming off the stern .... shouldnt be more than about 5° off from the boats centerline.
Back from a week of sailing around Narragansett Bay (RI) with a lot of practice going upwind. Of course everything you said improved the upwind performance incredibly with both the ability to point closer to the wind and the gain in speed. I now have good speed even inside the "no sail" zone of the windex. We had much practice in moderate and light winds.
As you recommended I tightened the main halyard, tightened the outhaul, brought the genoa cars back and flattened the genoa. I haven't tested the tune of the backstay but it seems balanced after slowly going into the wind when I let go of the wheel.
In moderate winds of 10-12 knots we achieved a speed of 5 knots on a very close haul which surprised me to no end. We had the boom over the centerline, the genoa car aft and the 150% genoa flat and about 4-6 inches off the spreader bar. We were zooming even though we were heeling about 25 degrees and sometimes hit 30 degrees. We would lose speed if I tried to level her out by easing the mainsheet so I kept it there and hung on. Is such a heel normal in those conditions?
In light winds of about 6 knots, we made about 2.5 to 3 knots headway upwind, little heel with the same settings, although I couldn't flatten out the genny as much as I would have liked since it would rub on the spreader bar.
The compass difference between the port and starboard tacks was around 100 degrees (except against the current). In the past, before these corrections, the difference between the tacks was 160 degrees! It was like going backwards.
I still have much to fine tune but you set me on the right course and it is much appreciated.
Sounds like you learned at lot! Generally if you are heeled over 25+ degrees consistently, you are overpowered. Most boats sail better when they are "on their feet" and not heeling so much. Learn how to depower in stronger winds by flattening sails, dropping the traveller, moving the genoa car, reducing sail area, etc. Makes for a more comfortable and faster ride.
Do you have telltales on the genny and main? If not, put some on. Will make a big difference in being able the trim the sails to the conditions and point of sail.
Jeff, I wonder if the boat your questioner is referring to is a Glibert 30? They were interesting-looking boats but did not sell very well as they were a bit pricey. The questioner also mentions 65* tacking angles. If this is 65* each side of the wind there is a definite problem. If it is 65* in total that would be highly impressive in a cruising boat.
|All times are GMT -4. The time now is 11:50 AM.|
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2013, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012