To lean or not to lean?

[jy51]

Modern hull shapes seem to rely on hull form as much as ballast ratios for stability, hence we see more and more beamy yachts with lighter ballast ratios.  To maintain minimum leeway, and sailing efficiency, these boats need to be sailed relatively upright and reefed early.

My last boat had a very high blast ratio, with long fin, skeg hung rudder, and deep wetted round body that helped it preform similar to a long keeled yacht. It was possible to sail and track with the toe rail submerged and water running alone the leeward side deck.

In comparison, COCO my Jeanneau 51 has a lighter displacement, lower ballast ratio and is far beamier, with an almost flat bottomed hull with chines that run back to the stern.

Obviously, myself and the admiral prefer upright sailing and nether of us would take kindly to a broach on a large yacht. Knowing this and starting a new learning curving I fitted a clinometer to COCO.

I assume the boat is designed to sit on its flat chine when in full sail.  Being a cautious sailor, I have reached the age were comfort overcomes the desire for speed and therefore I now reef early to maintain a comfortable angle especially on a long cruise. It’s interesting to note that while sailing in this manner on a beat the clinometer shows around 15 to a maximum of 20 degrees of angle, in lighter airs it can be as low as 5 to 10 degrees?

I am sure I am being over cautious and I appreciate that calculating optimum sailing angles has so many variables but It would be interesting to know if other owners would find this normal and wether or not they have and consult a clinometer.

[rene460]

Hi JY51, you are not alone in finding that you prefer more upright sailing than the adrenalin rush of sailing rail down, and I totally agree with your observations on the differences between modern and traditional boats.

We are all aware of the keel boat skippers description of “finding the groove”, and the easier sailing when you are able to maintain it. But the dingy sailors mantra is “flat is fast”.

Which is where your observation of modern hull forms come in. The wide flat hulls, while they still have significant ballast for stability, they also have much in common with the wide flat form of the modern dingy.

Please indulge me while I contribute a few thoughts on stability.

The righting moment contributed by ballast is actually zero when the boat is upright with the centre of ballast and centre of buoyancy in line. It is in balance but not stable at this point, but as soon as the boat starts to heel, the ballast contributes a righting moment as it moves away from the vertical force due to the boats mass. This righting moment increases with angle of heel until the mast is horizontal then, if we heel or tip further, starts reducing to a point of vanishing stability and for any further tip, the boat is more stable upside down.

I think we all know that much, but it is interesting to compare the effect of hull form. Again perfectly upright with the vertical forces in line the boat is still balanced but still not stable. Like with the ballast, a righting moment is produced as soon as the boat starts to heel. This is caused by the movement of the centre of buoyancy towards the low side of the boat, and for small angles of heel, can quickly produce a much bigger righting moment than the ballast, but both are in the same direction so both helping keep the boat upright.

Again the righting moment due to hull form increases until it reaches a maximum, certainly dependent on precise hull form, but a point comes where it starts reducing, and reducing very rapidly once the rail dips below the water, and disappears altogether once water starts coming on board. Hence the importance of storm boards in place in extreme conditions and large cockpit drains.

But the eternal fascination of sailing is in the pursuit of the optimum, in this as in other aspects.

As the boat heels under the side force due to wind on the sails the effective area which the sails present to the wind is reduced. So as the sail side force increases, the angle of heel increases, which increases the two righting moments but reduces the effective area of the sail so a balance point is found. And traditional naval architects went to a lot of trouble to optimise the hull form for sailing fast at this angle. But the question is, is it really fast?

While reducing the heeling force, the reduction in effective sail area also reduces the forward component of the total sail force, which is what is driving the boat forwards, not really what we want.

Here’s the rub, if you ease the traveller, or main sheet just a little, you also reduce the side force, but significantly, you alter the direction of the total force to be more forward, so increasing the forward drive, which should help speed. Ease it too much, and the loss of total force exceeds the benefit of the better force direction, so optimisation required.

Every boat and skipper will find a different preferred solution to this conundrum.

So may I contribute a little from my experience. My previous boat was an all out racing boat. Flat hull form, light weight, but also enough ballast to be classed as self righting. My wife and I cruising this boat were a real anomaly. But boy, it was fun, even if we never got the speed a race crew would achieve. I don’t race much except for annual participation in a major overnight race. I will always remember one particularly windy event, scary at night on a small boat, I decided I would start with a reef.   Of all nights, my always reliable reefing gear, let me down, and the cleat holding the reef in was slipping. I had my daughter and a girl from work on board, who were keen but not really skilled, so I went for the second reef, rather than no reef.

Now the point of this story only emerged after the race. The Commodore of the club running the race, was normally rostered as part of the race crew, but this was his year to sail. He was determined to do well, and had handpicked his best crew from his mates at the club. After the race he sought me out. “How did you do it?” he asked. I was not sure what he meant, so he went on to describe how he had passed me out on the lake in that wind.  What he was ever doing behind me, I will never know, but apparently we were sailing smoothly along, drinking our coffee in the cockpit, with our second reef neatly tucked in, while he, with his crack crew, was struggling to keep the boat upright, and had to really work hard to overtake that little boat out in front with clearly not enough sail up!

Of course, in my inexperience, I blew it all as the wind gradually eased, and I left it far too long to shake out those reefs, and ended back where I certainly deserved to be. I often wondered if my first reef had held as it should......... . .

But the lesson was clear, keep her flat, it’s comfortable and fast. If you are thinking about a reef, do it. At that point, it is certainly not slower.  Or certainly not for that boat.

But that is part of the fascination of sailing, every boat is different.

I hope that helps you answer your question, and prompts discussion of how others answer the question. There is room for many divergent opinions on where the balance lies.

Rene460

[alenka]

Rene.  Good points about easing sails.

I was always taught to set the sail as close as I could and let the boat settle. Then, ease the sheets, maybe only a couple of inches at a time and see what happens to the speed... If it goes up ease a little more... if it goes down sheet in a fraction.

With so many people in a hurry these days to fast track their courses and learning sailing in a week often the subtleties get overlooked or forgotten.  Chatting to one newbie over a beer he admitted he had never heard of sail trimming!

At the other end of the scale I do get a little upset when guests come aboard and declare they want to sail with the toe rail under the water. They might enjoy the excitement but are very rarely around to clear up the mess below afterwards or even put their hands in their pockets to replace broken crockery.

[jy51]

Rene460,

Many thanks for sharing your knowledge and experiences.   As said, I fully appreciate that every boat is different and will find its own optimum groove.   You explain the science, and there is many books that give tables and formulas used by designers, however, we all know the human element of sailing is experience, knowledge and gut feeling.

Your experience of less lean can mean faster sailing, while too much can introduce forces that simply increase sideslip or leeway is well documented and I'm sure we have all experienced this.

My last boat had a clinometer, but the novelty wore off after a short while, and I don't recall ever actually looking at it again.  I was interested to know if people use clinometers or just gut feels.  I would also stress that I understand that sailing angles, on a mono hull are not the only indicator of the need to reef.

Catamarans, for example, don't have the healing to indicate when stress levels are reached so they reef by numbers using the wind speed, so i'm led to believe!  Your Jeanneau is not too far from my own in design and size, my posting was more to hear the types of angles people feel comfortable with and find acceptable as a compromise, and wether they used a clinometer and know the angle or just go by gut feeling.

[fakinx]

Hi guys,
All points strait on! Thanks to rene460 for some lesson in physics. It might come handy for some to understand sailing better.
I've installed clinometer (it's crappy, two balls in tubes cheep plastic thing) several seasons ago and although we have certainly seen 40deg of bank (or more) that's really something not enjoyable at all. We saw side windows under water but can't say that for toerails. We still do it sometimes in up to 25 kt apparent wind but anything more is intimidating at least. Sometimes, we do it just for fun on short tacks with some youngsters on board with all below deck stuff safely secured. Like Alenka said it's not fun replacing something broken.
When heeled more boat is not as fast than it is with lower angles. Drag is apparently higher and also sails become sort of a break. Not to mention rudder becomes harder to a point it simply doesn't cope with forces any longer and boat spins. It happened and I know it's very wrong in so many ways.
With age we like much less heel and now up to 30deg is max. It is still considerable regarding comfort but up to that bank boat goes fast. Trimming the sails is usually my job and I'm more often than not too lazy to adjust to every change of wind direction or force. I rather just correct the course and all is fine again. I must admit, 15-20deg is comfortable zone for us and happy admiral means happy crew!
Sometimes, I am ordered to decrease heel and I simply point more in the wind. With 30deg app wind angle boat still goes satisfactory forward but heels about half less than in 40-45deg wind angle. Best solution in my opinion with almost no work done! WIn-win situation...
But than again, we don't do racing. Hardly a boat for that but sometimes it's fun to "race" with other boats on the same course to a destination (island or something). With younger crew things tend to get very competitive...

[rene460]

I am sorry JY51, in my enthusiasm for the topic, I completely forgot to answer your basic question, but you have kicked off a very interesting topic which is relevant to all.  But I am glad that my comments have been of interest to others.

My present SO 30i does not have an inclinometer.  The compass is horizontal in the binnacle so Does not have that extra indication.

Our previous boat, the compass was installed on a vertical bulkhead, and had an inclination around the bottom of the glass sphere.  But I never had time to read it.  That boat was the very definition of tippy, I remember sailing in company with my brother when it was new, and he said afterwards that he was sure he could see parts of the boat that should not be seen from another boat.  Fortunately I did learn to use the very wide traveller track to the required effect, but did not need an inclinometer, seat of the pants was more than adequate.

The boat before that had an inclinometer, the cheap type already mentioned.  The boat was the classic “dingy with a lid” of the early trailer sailers.  Fortunately a broad beam so quite stiff if you did not push it too far.   But my youngest son was very nervous, and would scream at the slightest tip.  A catamaran would not have been stable enough for him.  I showed him that inclinometer, and insisted no screaming until we reach (I think?) 15 degrees.  He reluctantly agreed but sat with his eyes glued to that inclinometer the whole time.

We laugh about it now, as a dad with three of his own, he is the one I am most comfortable with borrowing the boat for his family holidays.  

I could probably do with an inclinometer now, as I suspect I spend a lot of time, feathering too much to unnecessarily limit heel.  Needless to say it was a big change in boat behaviour from the previous two.  We also tend to limit sailing to lower wind strengths just for comfort as we get older, and health issues catch up.  I could be accused of being too timid.

rene460

[Bora]

I tend to use the coffee cup/beer can as the ultimate guide although it varies dependin on where it's put down, i'm not sure what angle that gives in the end but definitely too much heel just slows the boat.

With the beamier aft section you'll find the stern almost lifting which takes the rudder further out of the water and makes it less effective.  As soon as I find i'm having to fight the rudder i'll usually drop the traveller on the main a little (this is assuming sailing upwind and the genoa is set to the telltales).  I'll progressively drop it as required until the main just starts to lift and then it's probably time to put a reef in and pull the track back up.

I'll often use the mainsheet as a kicker/vang and trim with the traveller.

[ianf]

Years ago I was crewing for a couple of friends who had chartered a yacht to cross the English channel for a long weekend. They were both eager novices with me as the more "experienced" sailor!! 


They had everything out with the boat heeling over at a serious angle on a 20+ Kt beam reach and about 90 degrees of weather helm to keep the boat from broaching.


They thought it was great and that was as best they could do. I pointed out that with that much weather helm it was the equivalent of having a sea anchor deployed over the stern not to mention the stress they were putting on the rudder. I suggested they reefed in a bit and trimmed the sails to balance the boat to minimise weather helm.


When this was done they were astounded that they had increased speed by over a knot with much reduced heel and that the boat would almost steer itself.

[JEF]

Intresting topic our current yacht is SO440 deep keel twin rudders & fully chined hull. We are still in the learning stages of how best to sail her in all the various conditions. However looking at our records to date upwind sailing we have sailed her at a fairly comfortable lean angle of between 15 / 18 degrees at which she seems to sit on the chine with full sail up & easly achieving speeds comparable to the designer polar chart.

We will try her in reefed down settings and hope to sail her falter and record reasonadle speeds at undoubtably at much more comfortable sailing lean angle especially when the boss in on board.

Our previous yacht SO379 shallow wing keel twin rudders & 3/4 chine was a fantastic yacht we often sailed her upwind at around 18 / 20 degrees and would occasionally push on up to 22 degrees. With the twin rudders she would track if on rails and never let go it seemed to test us.. who chickened out first the skipper or the yacht.

hope the above comments interesting .

[Don Reaves]

I added a clinometer to my 2004 SO 35 about 15 years ago. It was a cheap one, with a single bent tube containing a small ball in some kind of fluid. It was useful for learning how to relate the way the boat felt under different conditions.

Mostly, it ended up being a way for my wife to indicate that we were heeling too much. Eventually, she decided that 5 degrees was her limit. After that, she decided that sailing wasn't fun for her, so now I always sail solo.

The cheap device worked for a few years. Now, the ball doesn't move at all. But I don't miss it, having learned what I needed to know. As others have said, reef early, keep the boat mostly upright, and reduce weather helm so the rudder continues to do its job well.

[jdl01]

Returning to jy51's initial post, the hull designs of the past 9 years with jeanneau perform best when sitting down on the hard chine but not deeply burying the chine. On our boat this usually translates to a roughly 15% heeling angle and continues to perform well up to 20%. This is also represented by a rudder angle of approx. 5% of weather helm. This generalized setting tends to hold me closest to the boat's polars. Setting this up is a function of sail trim, with backstay tension being a larger factor than I would have originally assumed for a cruising boat. Mainsail twist and sheet tension play a big roll in heeling and hence weather helm variance.

[jy51]

Well, I think we all agree, that modern hull forms, need to be sailed as upright as possible, if looking for maximum comfort and efficiency.  15 degrees maximum seems to be a good figure, without pressing her too hard.  The clinometer is a good indicator, but I do like the idea of that sliding beer can, it just about says it all!

[johannes]

Modern race boats with wide beam rely on some heel to reduce the wetted surface area. I'm not sure if the same applies to modern cruising boats, but I would expect it to some extent. 

Racers typically want as much sail area as possible for any given wind circumstances, but they also tend to have better sails than cruisers and are much more active in trimming. Better sails and better trim means you can have more sail while maintaining less heel. Plus they have crew sitting on the toe rail.

I grew up sailing a Fisksätra S30, a 6-metre type of of boat (long, narrow, shallow draft). I quickly heels to 30-40 degrees but stays there no matter how much sail you have. I still race on a friend's S30 sometimes. One time we were approaching the finish on a reach, and had to clear a gate and then tack the final 0.5 mile to the finish line. We had the big genoa and no reefs in the main. Just as we rounded up towards the finish line, there was a gust up to 50 knots. I was on the genoa sheet winch which was almost impossible to reel in because of the force. We heeled so much that the cockpit half-filled and I was sitting in water up to my waist. Even so, we stormed to the finish line like on rails. Around us the modern boats broached and blew out asymmetricals. 

[MalcolmP]

May 8, 2020 10:10:01 GMT johannes said:

......I grew up sailing a Fisksätra S30, a 6-metre type of of boat (long, narrow, shallow draft). I quickly heels to 30-40 degrees but stays there no matter how much sail you have. I still race on a friend's S30 sometimes. One time we were approaching the finish on a reach, and had to clear a gate and then tack the final 0.5 mile to the finish line. We had the big genoa and no reefs in the main. Just as we rounded up towards the finish line, there was a gust up to 50 knots. I was on the genoa sheet winch which was almost impossible to reel in because of the force. We heeled so much that the cockpit half-filled and I was sitting in water up to my waist. Even so, we stormed to the finish line like on rails. Around us the modern boats broached and blew out asymmetricals. 

In the UK we call that a "plank on edge" seriously narrow beam. I have seen these on occasion in Holland and Baltic




Many, many years ago with two friends we started repairing "Coronet" an old carvel built narrow "plank on edge" 30 foot design by Arthur Robb. It was an impressive design but loved to heel, my friend later sailed her singlehanded to NZ and Australia including double crossing of the Tasman (only image I can find still below)

 

[zaphod]

In racing flatter is almost always faster, and it also improves pointing. I can recall many times on many different boats where we would be trying to gain height on a nearby boat, and the crew would "max-hike", meaning they would get as much weight outboard as they could; heads under the upper lifeline, butts on the toe rail, arms outstretched. It was hard work, but it pretty much always paid off and made the boat sail slightly higher and faster.

When it comes to modern cruising boats, I can give you a recent example on my 39i. We were sailing in 20-25kts close hauled to get to our destination. I knew we were heeling too much, probably 20 degrees or more. When the boat heels that much you carry a lot more weather helm, and you can really hear it in the turbulence coming off the rudder. If you look back you can see the spray coming off the rudder at an angle to your transom. We were only doing 6.5kts, and I wasn't very happy with that! The boat was new to us, and I had never reefed her before. I got my wife to steer while I tried out the single line reefing system. (A very nice setup!) I put a single reef in, and flattened the sail out as much as I could, and the boat sat up, the noise off the transom got quieter as the weather helm was reduced, and just like that we were doing 7.5kts, and the boat felt much happier!

I know some old designs seem to like burying the rail, but I personally have never sailed a boat that isn't faster if you keep it flatter.

[NZL50505]

May 6, 2020 11:22:36 GMT Don Reaves said:

I added a clinometer to my 2004 SO 35 about 15 years ago. It was a cheap one, with a single bent tube containing a small ball in some kind of fluid. It was useful for learning how to relate the way the boat felt under different conditions.

Mostly, it ended up being a way for my wife to indicate that we were heeling too much. Eventually, she decided that 5 degrees was her limit. After that, she decided that sailing wasn't fun for her, so now I always sail solo.

The cheap device worked for a few years. Now, the ball doesn't move at all. But I don't miss it, having learned what I needed to know. As others have said, reef early, keep the boat mostly upright, and reduce weather helm so the rudder continues to do its job well.

Agree that inclino-meters usually end up becoming anxiety-meters and that's why I don't have them onboard any more!

[moonshadow]

On my SO469 I was very surprised at how much the boat would heel upwind in a good breeze. By about 18 knots apparent wind speed I found that a small reef in the mains really helped reduce heel and provides a lot more forward drive. Most of my previous experience was on racing boats so I was surprised that this roller furling main needs to be reefed so early.
As some of you already figured out, I realized that my mainsail is just worn out and the draft moves around too much in good wind. So..... time to shop around for a sail.

[zaphod]

Jun 29, 2020 11:46:22 GMT moonshadow said:

On my SO469 I was very surprised at how much the boat would heel upwind in a good breeze. By about 18 knots apparent wind speed I found that a small reef in the mains really helped reduce heel and provides a lot more forward drive. Most of my previous experience was on racing boats so I was surprised that this roller furling main needs to be reefed so early.
As some of you already figured out, I realized that my mainsail is just worn out and the draft moves around too much in good wind. So..... time to shop around for a sail.

Yeah for a racing sailor there is nothing worse than an old stretchy dacron sail when you have experienced the joy of a proper racing sail! Fortunately there are some very good cruising dacron cloth choices out there.
Our sailmaker has breathed a bit more life into our mainsail with a recut and full battens, but I fear our jib is beyond help. I am currently shopping for a new one.

Unfortunately your in-mast furling has some inherent limitations, but still a new sail that is flatter and has the draft in the right place will make a world of difference! Having said that, you should speak to your local sailmaker, they will likely be a le to recut your main and get a few more years out of it.

[Veloce]

Interesting topic. On Veloce, my SF32i we only race and we do it shorthanded.
I looked a lot for optimum heeling angle and didn't find any good source. This winter I will measure the hull sections and run it through a velocity performance prediction software.

However, I collected thousands of sets of data during the previous season and found that our best pointing and speed is somewhere between 15 and 19 degrees in winds between 6kn to 20kn.
18 degrees at 16kn is our benchmark and we keep a mark at 18 degrees on the clinometer.
Under 6 knots wind we tey to heel the boat as much as possible to give shape to the sails

Https://velocesailing.se

[captbillh]

how about this formula?

Leeway=10*heel/(speed)^2

I find that keeping the heeling between 12 to 17 degrees seem to optimize VMG. 

[fimacca]

I love to lean !

It feels faster to me (but is likely not ) and some sea spray in my face is even better. I think I am still a frustrated dinghy sailor.........
The wife likes mill glass seas and the motor on. Spotting dolphins.....

Horses for courses.......thankfully I have some mates that like getting wet like me........

I am yet to get a real sail in my new Jann ride, so am hoping a bulb deep keel and a light racy structure will supply what I need.

[zaphod]

HEEL! The correct term is HEEL, not "lean"!

Sorry, just had to say something!

[dbostrom]

Feb 7, 2021 18:48:25 GMT zaphod said:

HEEL! The correct term is HEEL, not "lean"!

Sorry, just had to say something!

One of my training skippers was a former USN officer whose last charge before mustering out and taking on random noobs as a sailing instructor was that of skipper of a 865' ship intended to deliver marines via helicopters to whatever fracas was in play.

Once I made the error of referring to a chart as a "map," in his presence. Such a nice guy, but this was beyond the pale; I was scorched, badly. 

Words matter. 

[jy51]

Feb 7, 2021 18:48:25 GMT zaphod said:

HEEL! The correct term is HEEL, not "lean"!

Sorry, just had to say something!

There was ment to be a subtle, even humorous play on words in that title, obviously not everyone got it! That is the question?  Maybe if Prince Hamlet had still been around he would have been less critical.

But just to be pedantic......we LEAN....the boat HEELS.  The word lean appeared in the title, referring to our personal state of angle, nowhere in any posting of mine or anyone else was the word lean used to describe the heel angle of a boat.  I’m sorry but your comment was uncalled for.

[jy51]

Feb 7, 2021 19:42:13 GMT dbostrom said:

Feb 7, 2021 18:48:25 GMT zaphod said:

HEEL! The correct term is HEEL, not "lean"!

Sorry, just had to say something!

One of my training skippers was a former USN officer whose last charge before mustering out and taking on random noobs as a sailing instructor was that of skipper of a 865' ship intended to deliver marines via helicopters to whatever fracas was in play.

Once I made the error of referring to a chart as a "map," in his presence. Such a nice guy, but this was beyond the pale; I was scorched, badly. 

Words matter. 

Do words matter?  Yes they do, as long as they are kind words. We are not in the Navy, we are pleasure sailors, and not everybody knows every nautical expression or terminology, but to act in a superior or arrogant manner, sorry that I can’t abide!.  As long as everyone on board clearly understands one another and can communicate through VHF and has a clear knowledge of collision rules, I’m ok with that.