Persistent Shifts for Dummies

By Doug

Roberto in Italy sent us this interesting chart. It shows four boats going upwind - the first 2 sail in a steady breeze while the other 2 sailing in a breeze that slowly shifts to the right:

• Black-left bangs the left and takes 16m 58s.
• Black-right bangs the right and takes the same, 16m 58s.
• Like most of us, red likes the lift but has to come into the mark on a big header, taking 17m 52s. This is 54 seconds more than the blacks because red is on the outside of a persistent shift.
• Green does something unusual - it sails on a header and then comes into the mark on a big lift, taking just 16m 9s. This is 49 seconds less than the blacks because green is on the inside of a persistent shift.

This is simple geometry - playing the shifts correctly means sailing a shorter distance which takes less time. But guessing when a shift is persistent is tricky - most people will stay on a lift like red and go the wrong way. It takes a lot of courage to recognize the shift is going to be persistent and take an early header like green to go the correct way.

The first time I learned about this was from Frank Bethwaite who was the Australian meteorologists at the 72 Olympics. Frank told me how amazing it was to watch Rodney Pattisson (GBR) who was the only sailor who recognized the long, persistent shifts at Kiel. Pattisson was the defending gold medalist and would start a leg going the wrong way on a header. This got him inside a persistent shift which only paid off at the top of the windward leg. Pattisson again won gold.

So Roberto's diagram is great because it quantifies the amount you can win or lose by not reading a persistent shift correctly. It's also great that most sailors don't sail at places like Kiel that have persistent shifts to worry about.

Actually, that's not true - we have persistent shifts all the time [Dummy alert - the following is simplified to make it a little easier to understand.]

The definition of a persistent shift is when the wind shifts one way and does not come back. In Roberto's diagram, the wind starts in a neutral position and goes right. If a shift cycle has 4 parts (go right, come back, go left, come back) and a leg takes less time to sail than a 1/4 of a shift cycle as shown in the diagram, then whatever the wind is doing is persistent. So it would make sense that the shorter the windward leg, the more likely the the shift will be a persistent shift. So the shorter the leg, the more you want to take an early header to get inside the shift.

So, how often does this happen? (Drumroll). Every windward leg! As we get closer to the windward mark, the remainder of the leg gets shorter and shorter. So, you guessed it, the top part of every leg has a persistent shift.

Some fun with numbers: Roberto's diagram has red losing 54 seconds and green gaining 49 seconds.

• If the wind completes one complete shift cycle (go right, go back, go left, go back) on a windward leg, then the top 1/4 of the leg has a persistent shift. This means that starting that part of the leg on a lift (red) means losing  54/4 or 13 seconds and sailing on the header (green) that gains 49/4 or 12 seconds - a total of 25 seconds!!
• If there are two complete shift cycles on the leg, green gains half of that, or 12 seconds on red.

How many times have we had good upwind speed only to round in traffic 12-25 seconds behind the leader who is in clean air?

Perhaps now we know why.

Gybing - Thoughts from Steve Cockerill, Frank Bethwaite... and me

By Doug

In the post about Laser Mainsheet Snags, comments were made about how Steve Cockerill's video suggests letting the boom out to initiate a heavy-air-gybe. I commented that surely letting the boom out would not work because it would be too unstable.

The boom is waaaaay too far out. But even a little out makes things unstable.

Then one of the sailors that Steve sponsors said this comment was correct and the reason for letting this boom out was to intentionally make the boat unstable.

So, let's recap:

• We're in strong wind on starboard and want to gybe.
• Almost all top-level events are held in open water, so there are probably big waves - a tricky situation.
• Steve suggests letting the boom out which is how you invite a death roll and swim (the twist at top of the sail is pushing everything to windward).
• The center of effort is now to the right of the boat which now wants to bear off.
• This initiates heavy air gybe with little or no rudder movement.

I have never tried or even seen this, but it's brilliant!! Except for one problem - it's a controlled heavy-air-death-roll-that-ends-up-in-a-gybe. Steve is a better man than me because my priority for a heavy-air-big-wave-gybe is getting the boom across without tipping.

This brings to mind comments from another world-class sailor. Several years ago, there was a Sailing World cover story article by Frank Bethwaite about how you bear off in a strong gust rather than the more intuitive heading up. 

Trying to head up in a strong gust.

Frank called this 'steering for balance' and it was controversial at the time, with lots of people saying that Frank was wrong. Frank was, of course, correct.

One of the key points Frank made was that by turning sharply in a gust, the boat wants to 'trip' over the centerboard. And the higher the speed, the more the importance as you lose control from the pressure in the rig.

I learned this by accident about ten years ago practicing on a local lake in a 30 knot breeze. With each gybe, the boom would slam across and there was a huge pressure on the rig and in the steering as I tried to get the right balance again. We've all had this problem.

So I tried something different and for me, counterintuitive: as the boom slammed across and I was on a new tack, I bore off to head straight downwind - steering for balance. The helm went neutral and everything worked beautifully, even in 30 knots.

So here's a combination to try when it's really honking - sheet out a little to start a gybe, let the boat bear off on its own, and as the boom slams across, bear off sharply to neutralize the helm. Oh and Ute, try to not wrap your mainsheet around the end of your boom!

In the 90s, the Worlds courses included a gybe mark and in a breeze it was referred to as the graveyard because so many boats would tip at the mark.  My practice sessions would include gybing at a certain point in a breeze and not waiting for lulls.  The goal was to have enough practice and confidence to gybe at any time while maintaining control at all times so that I could maneuver around boats that were scattered in the graveyard. That era inspired Laser sailors to practice and perfect various techniques.  That's the key ... pick a technique that works best for you and then practice it until you're comfortable.

Frank Bethwaite's New Book is Now Available

Fast Handling vs. Natural Handling

by Pam

I’m trying to connect some dots but I’m missing the line that connects them.  Perhaps someone can help me.

Dot 1 - Frank Bethwaite’s theory of fast handling (leaders) versus natural handling (followers).  I’m sure my description is an oversimplification and doesn’t do justice to Frank’s work but here goes.  Essentially, few people have learned fast handling techniques (coordinated movements of body, sheet, tiller, etc.) and the majority of people sail with natural handling techniques (more tiller movement, less coordinated movements). Frank discovered this difference with his sailing simulator when he took a group of follower adults and in a matter of hours, had them sailing competitively with world champions (on the simulator).  However, when they hit the water, they were awful.  So he got on the boats with them and watched them sail, then took the helm and showed them what they were doing (natural handling) and then showed them how it should be done (fast handling).  Basically, they were sailing like the majority of sailors … uncoordinated movements of body, sheet, tiller, etc.  After he showed them the difference, a whole new world of sailing opened up to them and they went from the back of the fleet to the front and from not always enjoying sailing to loving it.  Page 321, Chapter 24 - A New Way of Thinking,Higher Performance Sailing.

Dot 2 - Doug and I were out one Wednesday evening double-handed on a Laser and we took turns at the helm.  I was handling the boat just fine, keeping it flat, reacting to the wind, but I wasn’t fast.  Doug handled the boat like it was an extension of his body.  I could feel, see and hear the difference the boat made as it went through the water and it was fast.  Now this is just observing straight line boat speed.  It isn’t possible for me to observe him through tacking and gybing because I’m too busy trying to squeeze my growing behind underneath the boom and vang.  But I’m sure there is a difference between the two of us in the maneuvers as well.

Okay, Dot 1 (Frank’s theory) and Dot 2 (Doug/Pam handling differences) connect perfectly.  But, here’s the thing.  I don’t weigh as much as Doug.  In fact, I don’t weigh as much as the boat so my body movements are negated once the wind is just a touch beyond light.  Frank says the best way to learn fast handling is to go out when it’s windy and have someone that knows fast handling go with you and observe, teach and show you the difference.  When Doug is on the boat in wind, I have control, when he’s off, I’m in survival mode.  Yeah, I know, sail a Radial or 4.7 but bear with me, I have another dot.

Dot 3 - Doug and Eddie recently competed in C Scows at the Championship of Champions.  Essentially, they sailed as well as I do … 17 out of 20.  Doug would call home and tell me how it went and I swear it was like listening to myself.  He had no “feel” for the boat and no matter what he did, he couldn’t find the “feel”.  Most of the settings on the boat were set and taped in place since the goal was to test helmsmanship.  They copied the things others were doing but they were still slower.  They tried something different every race and boats that won in the previous race suddenly became a pig with Doug at the helm.  He kept saying, I don’t get it and I can’t get a feel for this boat.  He wondered if they were too light being double handed because this boat is always sailed at a heel and they struggled to hike enough on the low side (light air series) to heel the boat. 

Dot 1 - fast handling vs. natural handling.  Dot 2 - I sail more with natural handling because the boat does not always respond to my weight movements so it’s hard to get a feel for the boat and coordinate movements and weight is one of the things I see Doug use the most for fast handling.  Dot 3 - Doug, who has excellent fast handling technique on dinghies could not get a feel for a boat that outweighs him and does not respond to his body movement.

So, what is the fast handling transition from small boat to big boat?  It can obviously be learned and perfected.  Is it coordinated movements with crew or does the skipper have to learn better natural handling technique and abandon trying to use fast handling technique or is it something else?

Now everyone, including Frank, has told me that I can’t be competitive in a full rig at my weight.  However, what is the transition from small boat to big boat and can I make it on a small boat to a small boat with a bigger sail?  After all, when I asked Frank if I could be competitive in a full rig, he didn’t respond with a flat out no.  He weighed the possibilities and talked about hull size, weight, sail size, physics, 18 footers being scaled to skipper size, and then very gently said probably not.  But Jeff Linton once told me that while I probably can’t be competitive in higher winds, I could certainly try to become a more competent sailor and stay on the course in windy conditions and then, through an entire series, the law of averages would give me a shot at being competitive in years when the wind is on the lighter side.  So, I’m back to the missing line to connect my dots.  Does anyone have an answer?

Frank Bethwaite, Brett Beyer and Doug

by Pam

AUS lifted inside, CYP ahead outside

Doug writes his posts primarily for me and nothing gets posted until I understand what he is saying and in his efforts to simplify things for me, he learns too.  I started this blog because I thought people might enjoy learning along with us.

Recently, Doug wrote Angles: Better Than Boatspeed which drew some comments from an Olympic sailor who did not agree.  Doug recently asked Brett Beyer offline about his thoughts on the post.  Brett didn’t agree with some aspects of Doug’s post and supplemented that there was another factor to consider, TIME (before laylines, knocks, etc.).  Brett would not have tacked if he were CYP.  He felt CYP's only option was to wait for the inside lift to fizzle and for the wind to shift back (knock) where CYP would then be able to tack into a more favorable position.  I must admit I didn’t totally understand his comments after working so hard to understand Doug’s post.  But since Doug’s time with Frank Bethwaite is still a significant influence on his sailing and since Brett knew and worked with Frank as well, and even wrote the chapter on Laser trim and handling in Frank’s last book, Fast Handling Techniques, which will be available later this year, I decided to go back to the source.

First, I pulled out Doug’s copy of Frank’s latest book, Higher Performance Sailing which directed me to chapters 10, 11, and 12 of High Performance Sailing with respect to persistent shifts.  And there, in Doug’s book with the inscription from Frank ‘With pleasant memories of shared dreams,’ I turned to a heavily highlighted Chapter 11 with terms like angles, percentage sailing, fleet sailing [round-the-buoy racing], minimum-time sailing [ocean racing], defensive sailing, etc.  Some familiar terms.  It’s official, Doug has reached that age where he’s learned so much, he’s forgotten from whom he learned it.  He couldn't recall Frank mentioning angles or percentage sailing.

On page 131 of HPS1, Frank explains that knowing when to tack is easy if your mind holds a correct image of the wind.  He describes the 'direct method' of accurately sensing the wind which he says is particularly effective in unsteady winds:

The rule is, ‘if a boat on the same tack, either ahead or behind, is pointing significantly higher than you are, or a boat on the other tack is pointing lower than expected, you must be in a header, so tack.’  The great advantage of this method is that the present pattern in your area is continuously revealed, and as well, the direction of the mean wind is constantly revealed and corrected.  Use this method, always, when you are in close company, and never forget to keep looking over your shoulder, at the boats behind, particularly when you are in the lead.

Hmmm… this sounds like the basis of Doug’s angles post.  When close to another boat, you are either lifted or headed relative to the other boat.  Doug has taken that to mean that when near another boat, he is judging his lifts and headers by the other boat and not the course or compass and he tacks accordingly.  While Brett acknowledged AUS was lifted and making a relative gain, he indicated CYP might also be lifted and tacking would negate that.  But Frank’s statement indicates that the angle to the other boat is telling you what the wind is in your area.  Now I’m confused.

But wait, it gets better.  Then we move on to additional statements in HPS1:

The technique above, slightly extended, is what fleet sailing is all about. 

When you are sailing in conditions in which there is no regular pattern this technique can be further extended to become ‘percentage sailing’.

If in these conditions you elect, instead to 'minimum-time' sail, and let the backs and veers run their course and tack on the nodes, you may well sail a shorter path to the mark and finish further ahead.  This is the technique of the ocean racer.  But if you are sailing around the buoys and do not have the luxury of being able to wait forever for the next back or veer, and the wind direction does not behave as you expect, you may well finish further behind.

Skill in percentage sailing the fleet is no defense against minimum-time sailing, split fleets, nor on downwind legs.

Percentage sailing will fail as soon as the wind shifts become regular.

And then, I was totally lost.  Doug’s concepts are simple for me to follow.  Brett, no doubt, is a better sailor and coach than Doug.  But, Brett is like a finely tuned racing machine.  Put him on a small, shifty lake like Doug normally sails on and he might never have room to get out of third gear.  So, maybe Doug knows a trick or two about light and shifty that Brett does not.  Wasn’t Weymouth on the shifty side?  Now Brett did say that he thought the angles were more significant in winds over 15 knots.  But, Doug thinks angles are more significant in light, shifty winds.  Frank did say “unsteady” winds but does that mean strong gusty winds or light shifty winds.  Somewhere between the three of them is the answer, but I’m not equipped to sort it out. My gut feeling is that 50% of the time Doug would be right and 50% of the time Brett would be right ... or maybe I'm 100% wrong.

Persistent Shifts

By Doug

Mark Bethwaite (AUS) won FD trials for the 1972 Munich Olympics and his father, Frank, was the team's meteorologist.  Rodney Pattisson (GBR) ending up winning the FD gold medal and Frank's amazing notes and graphs showed how Rodney used persistent wind shifts to win.

First a definition: a persistent wind shift is when the wind shifts one way and does not come back. If you sail with a compass or by staying on a lift, you end up going in a big circle. This is "sailing the course" at its worse, and we've all done it. It's tricky because we only realize it's a problem at the top of the beat when we have to come into the mark on a huge knock.

What Pattisson did was take an early header and then have the lift take him up to the mark. The gains were only at the end of the leg if the persistent shift continued. A brilliant and gutsy move, and worthy of a gold medal.

It's gutsy because if the shift is not persistent Pattisson is completely out of phase and loses to everyone who stays in phase.

The shifts at Kiel were slow and, with Olympic medals at stake, Frank was amazed by how Pattisson accurately predicted when and by how much these shifts were persistent.

When you think about it, their likelihood is a function of the length of a windward leg and the speed of a boat. An opti sailing a two-mile leg will have lots of shifts back and forth, while an AC 72 sailing off St. Francis Yacht Club will probably have a part of just one persistent shift. So, it's not surprising that this phenomena was first noted in FD races where the boats are really fast.

Lasers are much slower, so persistent shifts should not be as much of a factor. This leads me to ask you a question. Think of your last 100 windward legs ... how many had a persistent shift? Most people guess between 0 and 10. One brave person told me 20.

It's a trick question because, in IMHO, the correct answer is 100. You see, the last shift at the top of each windward leg is persistent. Why? Because you round the mark before the shifting back and forth has a chance to continue.

This is why we have to ignore our compass and our gut stay-on-a-lift instincts at the top of each windward leg. If the wind is shifting back and forth and we're within one cycle, we have to remember to take a header if it will get us inside the final lift to the mark.  This is especially important on short windward legs.

When this works, it can be spectacular. When it does not, it's an I-can't-believe-I-made-that-bonehead-mistake moment. An example of this working can be seen at the bottom of this post.

Fast Handling Techniques

By Doug

When we visited Frank after the Brisbane Worlds, he told us that he was working on another book that is a companion to his 2008 classic Higher Performance Sailing. He gave us a copy of Chapter 7 which is about sailing a Laser written by Brett Beyer. Brett writes about upwind, crosswind, and downwind in all sailing conditions and has some really good material that has helped him win his eight Laser Master Worlds.  Frank's final book will be available in December and you can pre-order it here. Would make a great Christmas present for any Laser sailor (hint, hint Pam).

Frank Bethwaite 1920 - 2012

by Doug

Frank Bethwaite - March 2012

Frank was the most remarkable man I have ever met. 

Sail World

Laser Cheat Sheet - Smart Steering

By Doug

Laser Cheat Sheet

When I was in my 20's living in Sydney, Frank Bethwaite asked for my help with his wind tunnel testing as he explored wing masts for the Little Americas Cup. Frank was sure that two wings working together would generate more lift than just one.  It was absolutely fascinating stuff. Forty years later, his design has proved to be correct and has been widely adopted.

Something else Frank talked about at the time was what he called the "Concertina effect" where the wind characteristics change as the velocity changes. Here's an example from a Dallas weather station:

The wind is steady from the south until it drops and becomes unstable, and then becomes steady again when the wind picks up. Here are more pronounced examples:

What we are seeing is that wind up high slows down when it hits any surface, and the more it slows down the more it zigzags. Traffic also does this - when a car stops suddenly others swerve out of the way. You can also see this with molasses slowing down - it does not stop evenly but zigzags back and forth.

The more something slows down, the more it moves back and forth. This is why the light wind is shiftier than a stronger breeze. And why the Cheat Sheet refers to sailing in a light wind as having to "be smart." In these conditions, I would rather sail an old, beaten-up Laser and be aware of my surroundings than have a fast Laser keeping my head inside the boat. So, the first tip for being smart is feeling and seeing the wind.

My years of sailing have taught me to be aware of where the wind is coming from and how it is constantly shifting. Pam and I play this game when outdoors about what the wind is doing and she's getting good at feeling it. On the water I like to wear as little as possible to get the best feeling. Sometimes the wind is so light there are no clues on the water or on the boat about its direction. What I do is close my eyes and move my head until both sides of my face feel the same, and then open my eyes facing upwind. And because of Frank's Concertina effect, I know it will change again soon.

Sailing in really light winds can be frustrating, but knowing where the wind is coming from and knowing it's constantly changing will give you a huge advantage. It's not my favorite part of sailing, but having this advantage makes it a lot more fun.

Wednesday Night Lessons - 2

by Pam

We arrived at the lake planning to sail two boats but my boat became disabled upon rigging. I won’t say what happened but I didn’t do it. So, we sailed double-handed again and I got to see an up close demonstration of boat handling that still has me in awe.

First, I worked on steering upwind and downwind, trying to use less helm and get back to feeling the boat. Doug would lay on the bow looking at the sky and could feel when I did something right or wrong with the gradual progression toward getting better.

Then Doug took the helm. The boat is like his avatar. He grabs the main sheet, tiller and connects his butt to the deck and there is this transformation where the boat becomes an extension of his body. He showed me windward heel, trapping the wind and using it to squirt forward. He did this thing over and over and described every step as he did it. I could see it, feel it and even hear the acceleration of the boat. He’d say ‘the guy next to me didn’t do this and I just gained a boat length.’ I saw what he did but can’t even fully describe it. He’s completely tuned into the wind and the boat and it’s a multi-coordinated movement of weight, helm and sail adjustment and the boat just digs in, grabs and wind and water and takes off. Just an amazing feeling. If I could sail a boat like that I’d be out there all the time.

Then the light went on. I’ve been scanning portions of Frank Bethwaite’s book, Higher Performance Sailing where he is talking about the difference in a sailor that simply relies on the helm and steers the boat versus one that uses coordinated movements. The difference is exactly what Doug and I experience when we sail at the same regattas. One of us is at the middle or back of the fleet and the other is at the front. And according to Frank’s experiments, that will never change until I learn to coordinate my movements. I definitely want to learn more about the sailing simulator Frank has developed that can take an absolute beginner and after 90 minutes a week for 5 weeks, have them sailing with the coordinated movements and speed of world champions and they never develop bad habits or intimidation of heavy wind. Surely, I read that wrong ... or why wouldn’t everyone want to learn to sail that way.

Laser Cheat Sheet

by Doug

When I was 20 and living in my native Montreal, I bought myself an unusual $1,800 present - a one-way ticket to Sydney. Yes, I was restless and yes, that's what it cost back in 1971. One of my goals was to crew on one of Sydney's famous 18-footer skiffs. But the skipper that I was introduced to talked me out of it. He said, "For every hour on the water, you'll have to spend three hours working on the boat." I asked, "What would you do if you were me?" He paused and then said, "I'd call a gentleman by the name of Frank Bethwaite."

2012 with Frank in North Sydney

Thus began a 40-year friendship with the most remarkable man that I have ever met. Frank was the father of the NS-14, a very simple but wicked fast development class with a small sail and no trapeze. Yet it planed upwind. Every high-performance dinghy in the world can trace its roots back to the NS-14 and, of course, Frank's son Julian went on to design several classes including the 49'er.

2012 Pam with Julian at Bethwaite Design

So at the ripe old age of 20, I became the race secretary of the NS-14 association and a protégé of Frank Bethwaite... talk about luck!!!



1971 Frank and Julian sailing their NS-14

[I took this picture in at Northbridge SC. There's an interesting story behind it that helps explain why jibs are so efficient, and will be the subject of another post. Frank used this picture in his first book High Performance Sailing.] In spite of its high performance, the NS-14 was actually designed for husband and wife crews. So one of the challenges was finding a simple way to set up the controls. Frank had a brilliant solution. For the three wind settings (light, medium, and fresh) he had "datum marks" of one, two, and three red dots on all of the controls. Every NS-14 Frank built had these so that anyone could set up the sails perfectly every time.

Fast forward 38 years and Pam is interested in learning how to race a Laser. We would talk for hours and she would always say, "Make it simpler." So I would write things down - how to set up the controls, the strategy for starting, playing the competition, etc. But it seemed that every time we talked about it, she would say, "Make it simpler." The result is the cheat sheet in the right column which I laminate and give out at clinics. Much of what I know is here.  The purpose of the cheat sheet is to allow anyone to set the controls correctly for all lake conditions and simply focus on boat handling and tactics.  The controls should be the easiest part of sailing a Laser.

A disclaimer: The settings I recommend are basic and have served me well when sailing on lakes in Dallas.  There may be variances that others use that work but these settings should be competitive enough to keep you at the front of the fleet.  Major events like world championships tend to be in open-water and these settings are different.  Coincidently, Brett Beyer has written about this in Frank's upcoming book and he has generously agreed to give his perspective of settings in a future post. Describing my cheat sheet will take several posts - we'll start with the three columns that, not surprisingly, can be traced back to Frank's datum marks.

When you buy a boat, you're really buying three for the price of one, but only one of them has to be fast. For the one that you sail in light air, you have to be smart. Speed without smarts means you'll go quickly the wrong way. For medium conditions, you need absolute speed so you need to be fast. For above a certain wind strength (15 for me), boatspeed goes out the window and its all about conditioning, so you need to be fit. Setting up and racing a Laser is all about being smart, being fast, and being fit.

Your weight determines your strength and weakness. If you do not weigh much, you need to be smart and win the light races. If you're weight is average, you have a chance of winning in all conditions but you'll need boatspeed. If you're heavy, you had better be in shape.

I do not know of any single person who is the fastest in all conditions, so it's best to perfect your own conditions and then be reasonably competitive in the others. For example, a race in Laser world championships will not start in very light conditions (darn!) so I need to be really fast in medium conditions and hopefully fit enough to hang on in windy conditions. My finishes in a 72-boat fleet at the 1999 Master Worlds made this really clear - in conditions under 15 they were 1, 1, 1, 1, 2, 3 but over 15 were 7, 8, 9, 10, 10. I have worked hard to improve my heavy-air sailing but sailors from countries that produce great heavy-weather sailors (AUS, NZL) are now getting really fast in the lighter conditions, as we saw recently in Brisbane. Laser sailing will continue to evolve.

In another post, we'll look at setting up the controls before the start and then going upwind.