# pointing, pinching, VMG



## BarryL

Hello,

I am racing my boat in a double handed series. This is simple, casual, non-spinnaker racing (for me). I am sailing with my daughter and we're having lots of fun.

Last night we sailed in just about perfect conditions: Wind 7-10 true, flat seas. On the upwind leg I had the sails trimmed in hard. Halyard and outhaul set properly (IMHO). I had the upwind mark programmed into my plotter (B&G Vulcan), I was displaying SOG and VMG to the mark.

I noticed that VMG was highest when it felt like I was pinching. SOG would decrease but VMG would increase. The inner tell tails on the headsail were fluttering. The heasail was in all the way, the cars were set right too (even break of the tell tails from top to bottom. 

I definitely felt like I was pinching and if I headed down a little the SOG would increase and the telltails looked better but the VMG decreased.

So, am I best off trying to maximize VMG or steering to the tell tails?

Thanks,
Barry


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## SchockT

BarryL said:


> Hello,
> 
> I am racing my boat in a double handed series. This is simple, casual, non-spinnaker racing (for me). I am sailing with my daughter and we're having lots of fun.
> 
> Last night we sailed in just about perfect conditions: Wind 7-10 true, flat seas. On the upwind leg I had the sails trimmed in hard. Halyard and outhaul set properly (IMHO). I had the upwind mark programmed into my plotter (B&G Vulcan), I was displaying SOG and VMG to the mark.
> 
> I noticed that VMG was highest when it felt like I was pinching. SOG would decrease but VMG would increase. The inner tell tails on the headsail were fluttering. The heasail was in all the way, the cars were set right too (even break of the tell tails from top to bottom.
> 
> I definitely felt like I was pinching and if I headed down a little the SOG would increase and the telltails looked better but the VMG decreased.
> 
> So, am I best off trying to maximize VMG or steering to the tell tails?
> 
> Thanks,
> Barry


If the VMG number is better, then that is what you should do, barring any other factors. You were probably able to get away with pinching because of the flat water. Had there been bigger seas you likely would have been forced to foot off a bit for power through the waves.

When you say you were "pinching" how close to the wind were you sailing?

Sent from my SM-G960W using Tapatalk


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## outbound

You’re racing. The fastest time around the course wins. If your electronic way points give you the fastest way around the course then vmg is the only thing that counts. Of course this assumes your electronics account for current, set and there are no wind shifts. 
A possible explanation lies in your sails. You’re right they should be the perfect foils to give the best vmg. In which case it’s possible if their are places where there aren’t telltales that are producing most of your drive. This could be from trim or the shape of the sails themself (stretch, creep (if laminated) or other issues.


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## colemj

Inner headsail telltails just starting to break or flutter is exactly where you want the sail trimmed/boat pointed. For the main, you want the top one or two breaking ~50% of the time.

Mark


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## RegisteredUser

Good experience
I hope she hets tired hauling away the silver...


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## SanderO

in those conditions the VMG is what you want to go with.


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## Sailormon6

You didn't say much about how your mainsail was trimmed, except that generally your sails were "trimmed in hard." That suggests that your mainsail was trimmed in to the boat's centerline.

What's the first thing sail instructors teach about trimming the mainsail? Trim it in close and then ease it out until it just begins to lift at the luff. But most racers trim it in to the centerline, so that the sail lays down smoothly from luff to leech.

Maximum speed and efficiency are achieved when the jib and mainsail are in balance. If the mainsail is over-trimmed, the mainsail drives the transom to leeward, and the helmsman must use rudder to counteract that tendency and keep the boat on it's heading. Using the rudder creates drag and slows the boat. If the boat has a tiller, you can feel the tiller pressure, and adjust the mainsheet or traveler to eliminate the tiller pressure. If the boat has a wheel, there isn't much "feel" to help you, and you just have to know that it's happening and trim the mainsail accordingly.

Why did you "feel like it was pinching?" Was it because the mainsail was lifting slightly at the luff? If so, then that means you were probably well-trimmed and steering in the groove.

If the jib telltails are streaming correctly and the mainsail telltails are streaming correctly and the mainsail is lifting very slightly at the luff, your sails are well balanced and rudder drag should be minimal.


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## pdqaltair

When used to race, I would take some races just as practice sessions. Using other boats as trial horses, I would tweak and test, focusing on what worked, without fretting about out come. In fact, those races often accidentally went pretty well, because I focused on sailing well instead of stressing over position. With beach cats, it's usually more about speed than tactics anyway.

Sailing alongside other well sailed boats is a great way to tune. The best trim is boat and condition specific. That's the fun!


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## Sailormon6

Sailing to your best VMG angle doesn't mean your sail trim is optimal. It merely means you're at the most favorable angle, despite the fact that your sail trim might be poor. If you want to maximize speed and pointing, you first have to fine tune your sail trim, and then find the optimum angle for the best VMG.

Optimizing performance to windward is primarily about optimizing sail trim, not about optimizing your VMG angle.


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## SanderO

Sailormon6 said:


> Sailing to your best VMG angle doesn't mean your sail trim is optimal. It merely means you're at the most favorable angle, despite the fact that your sail trim might be poor. If you want to maximize speed and pointing, you first have to fine tune your sail trim, and then find the optimum angle for the best VMG.
> 
> Optimizing performance to windward is primarily about optimizing sail trim, not about optimizing your VMG angle.


VMG angle is a bit contradictory, My understanding of VMG is velocity made good toward a fixed point. The actual angle will vary as you approach that point.


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## outbound

Some of this depends upon the program used to calculate vmg but the ideal is to have the best vmg with the sails perfectly trimmed and the tell tales horizontal. 
Image you on a reach but need to be on a beat. While on the reach your boat speed is higher than on a beat (true for every sailing polar) and the telltales are perfect. You don’t touch the sheets and go to a beat. Now your boat speed falls but your vmg rises. This is an extreme example as in this scenario your sails will luff to to the point where drive will be lost. But there are multiple points before this occurs where your telltales will go squirrelly but vmg improve.
Suggest go on a day sail. Find a situation that reproduces your experience. Put the boat on AP course setting. Then fool with the trim watching vmg. Vmg will improve further when ideally trimmed. 
The OP notes light air 7-10kts. Here you have two choices. Go for a very flat sail to prevent back eddies and maintain laminar flow across the sails. Or increase draft and cord to get the most drive from the sails. One will be faster. The sails will look very different although angle of attack is the same. 
Examine your sailing polar. In general the point at which boat speed falls as you continue to head up is the point at which you are “pinching”. This is true cruising or racing. It’s built into the basics of your boat. You may not do as well as your polar as your sails age. I pinch to get around a headland or some such situation when cruising but try to avoid pinching while racing. While racing will try to stay right at the edge of pinching which requires a very alert helm. Someone reading the water (if light air) not just the wind indicators. Some one reading the natural oscillations of wind direction in moderate to light air. In heavier air although you need to consider that you also need to consider the seas trying to stall the boat so angle of attack may vary. This requires very alert trimmers keeping up with the changes the helmsman is making as necessary.


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## SanderO

Color me stupid but.. if your GPS plotter program is accurately computing VMG as max... it hardly matters how your sails are trimmed.... your are moving a fast as you can toward your destination. It may be counter intuitive... that your sails APPEAR to be less than properly trimmed... but the VMG tells a different story.

The curious thing is WHY are the tell tales telling you a different story than your computer?

Could it be that your keel will is not trimmable provides lift related to current and heel?


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## BarryL

Hi Guys,

Thanks for all of the comments.

On the boat I normally race on I usually trim main. On that boat the owner drives. He's good at it and we are successful. However, he's not a fan of electronics. The trimmers trim and the driver drives. He steers to the tell tails but since no one is looking at VMG I don't know if the VMG would increase if he headed up a little more or down a little. Next time I will use my hand held GPS and try to pay attention to that.

On my boat for upwind work I will set halyard tension, outhaul, headsail cars, backstay, etc for the wind conditions. Then we trim the sails and I steer. On Monday the headsail was in as much as possible. The top third of the leach was against the shrouds so I can't trim in any harder. The mainsheet was on hard and the traveler was used to pull the boom to center line. Normally I would sail to keep the tell tails streaming. Monday was first time I really paid attention to VMG and that's when I noticed VMG increasing when i was 'pinching'. There was minimal weather helm and the boat sails very nicely.

The sails are in good condition. The main is dacon, bought in 2015. The headsail is a 135 laminate, bought in 2016. Bottom is clean, foils clean. 

Next time I'm out for a day sail I will do some more testing and tweaking.

Barry


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## SanderO

There have many times when I am sailing back to my then mooring out in Shelter Island when the wind was very light and I decided to motor sail because I didn't want to tack. I would roll in the head sail and try to keep the main up without "losing its sailing shape" . I was motor sailing too hard on the wind I got no help from the main and worse it was more drag. I found that the main could add a bit of speed as long as it was drawing. Now way could I sail that close to the wind with two sails or even one.

Don't forget to consider the impact of current on your VMG and CMG.


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## outbound

Do you get the same phenomenon in stronger wind?. How far do you need to let sails out to get them looking good? Do you trim front to back? Is the jib over trimmed closing the slot and making the main luff? Do the shapes of jib and main match?
I like you don’t understand this. Have gone faster with part of the sail out of trim and the rest good at times but not the whole thing.


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## pdqaltair

SanderO said:


> ...The curious thing is WHY are the tell tales telling you a different story than your computer?...


They aren't. Telltales describe the flow around certain parts of the sail. But what is the best flow pattern? That varies with the boat, the condition of the sails, and the boat. Some lifting and some stalling can be correct, depending on the course.

You are seeking best VMG. Telltales are only a part of the picture, like oil pressure or engine rpm to a race car driver. Lap time is what matters. This is why trial horses were so vital before VMG computers (they still are), because not everything is visually obvious.


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## Sailormon6

Barry, I'm a firm believer in steering with a very light touch. A sailboat with a well tuned rig will tell you how to steer it. If you're sailing closehauled and a little puff comes along, and the boat heels a little more, and you have to tug a bit more on the tiller to hold it's heading, that's the boat's way of telling you that it will be happier if you'll let it head up to windward 2-3 degrees. A happy boat sails faster and points higher. If you can let the boat come to windward 2-3 degrees while maintaining the same boat speed, your VMG will improve. If you don't let the boat head up 2-3 degrees in that situation, you'll have to hold it off the wind with the rudder, and that will cause drag and a loss of boat speed. When the puff subsides, you'll have to bear off the wind to keep your speed and VMG optimized.

I think your mainsail is slightly overtrimmed when it's trimmed to the centerline. When you let the boat come up to windward slightly, it takes a little pressure off the mainsail, reducing rudder drag slightly, so your boat pointed 2-3 degrees higher without losing boat speed, and that's why it produced an improved VMG.

My suggestion is, when you're closehauled, ease the mainsail off from the centerline until the luff just begins to lift, and then trim it in just a skosh. Then steer with a very light hand on the helm, and, when the boat tells you it wants to head to windward a bit in a puff, let it. That will maximize your boat speed, pointing and VMG, and reduce drag 100% of the time.


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## jblumhorst

How does your instrument system derive VMG? Is it VMG relative to true wind? Or to a waypoint? How sophisticated is your wind instrument?

IMO, you should be, first, picking your angles based on strategy and lay lines to the mark or destination, and then subsequently maximizing boat speed at that chosen angle. 

In other words, “sail to target speeds”. 
Figure out how to tell the difference between direction headers and velocity headers. How you drive and trim is different between the two. 

Google “velocity header target speed” and “sailboat target speeds”


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## SanderO

jblumhorst said:


> How does your instrument system derive VMG? Is it VMG relative to true wind? Or to a waypoint? How sophisticated is your wind instrument?
> 
> IMO, you should be, first, picking your angles based on strategy and lay lines to the mark or destination, and then subsequently maximizing boat speed at that chosen angle.
> 
> In other words, "sail to target speeds".
> Figure out how to tell the difference between direction headers and velocity headers. How you drive and trim is different between the two.
> 
> Google "velocity header target speed" and "sailboat target speeds"


Great point. My instruments use a waypoint for VMG wind has nothing to do with it. Whatever factor improves the VMG it will show... upwind or downwind or no wind.


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## BarryL

Hi Judy,

Thanks for your note.

My electronics are a B&G Vulcan plotter, Raymarine ST50 wind, speed, depth. They are integrated so the plotter can calculate true wind.

The courses we use are windward leeward. I have the marks programmed into the plotter and the plotter is displaying SOG, VMG, COG, DTW, TTW, BTW, and a bunch of other things. The Vulcan is designed for sailing and will display laylines, polars, etc.

I also have a garmin GPSMAP 78SC. It is not integrated to any instruments but does have waypoints in memory.

The Garmin and Vulcan both display VMG and it was very very close on both.

Since the course is windward leeward for the upwind leg I usually just trim the sails in as far as possible - headsail sheeted in until the leetch hits the shrouds, main in as far as possible, then traveler up to get boom on centerline, and then I steer to the tell tails.

I will do some research on velocity header target speeds.

Barry



jblumhorst said:


> How does your instrument system derive VMG? Is it VMG relative to true wind? Or to a waypoint? How sophisticated is your wind instrument?
> 
> IMO, you should be, first, picking your angles based on strategy and lay lines to the mark or destination, and then subsequently maximizing boat speed at that chosen angle.
> 
> In other words, "sail to target speeds".
> Figure out how to tell the difference between direction headers and velocity headers. How you drive and trim is different between the two.
> 
> Google "velocity header target speed" and "sailboat target speeds"


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## sailingfool

Genoa trimmed to touch the shrounds would be far too close for any of the various boats that I have raced. 2-6" off the lower spreader has been a general guideline...2 in stronger breeze...sailing closer...6" in lighter air.

Sent from my SM-G965U using Tapatalk


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## Hudsonian

You were probably on the headed tack. On the headed tack pinching increases your VMG. On the lifted tack footing will increase your VMG.


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## JimsCAL

The short answer since you are using the a waypoint on your chartplotter, the fastest VMG is best. 

As to your boat and sail trim, that's harder as every boat is a bit different. From your description, I would say you were overtrimmed, but it sounds like the boat was moving well.


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## Explorer

VMG will give you the fastest way from where you are now in your current conditions, but it won't tell you about how in another 50m you will be in the middle of a current running at 2 knots against you and slow significantly. It won't tell you that you are sailing into a windshadow of a headland and will lose power and speed. It won't tell you that if you tack now you will remain in the area with the a channel of higher wind velocities. VMG is a useful tool, but not everything, especially in areas with lots of landforms and strong currents.


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## SanderO

VMG... is an instantaneous analysis of the boat's performance base on wind speed, angle and boat speed through the water,

"*Velocity made good*, or *VMG*, is a term used in sailing, especially in yacht racing, indicating the speed of a sailboat towards (or from) the direction of the wind.[1][2] The concept is useful because a sailboat cannot sail directly upwind, and thus often can not, or should not, sail directly to a mark to reach it as quickly as possible. It is also often less than optimal to sail directly downwind."

This has nothing to do with your chosen mark, waypoint or destination.


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## SchockT

SanderO said:


> VMG... is an instantaneous analysis of the boat's performance base on wind speed, angle and boat speed through the water,
> 
> "*Velocity made good*, or *VMG*, is a term used in sailing, especially in yacht racing, indicating the speed of a sailboat towards (or from) the direction of the wind.[1][2] The concept is useful because a sailboat cannot sail directly upwind, and thus often can not, or should not, sail directly to a mark to reach it as quickly as possible. It is also often less than optimal to sail directly downwind."
> 
> This has nothing to do with your chosen mark, waypoint or destination.


Im the real world VMG has everything to do with your destination. In fact most GPS systems won't even display a vmg number unless you have an active way point.

Sent from my SM-G981W using Tapatalk


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## SanderO

SchockT said:


> Im the real world VMG has everything to do with your destination. In fact most GPS systems won't even display a vmg number unless you have an active way point.
> 
> Sent from my SM-G981W using Tapatalk


I believe you are confusing velocity made good to a waypoint - and velocity made good on Course or *VMC*

"The term *Velocity Made Good* (VMG) is often confused with term *Velocity Made good on Course* (VMC), and often used interchangeably.[1][2] VMC is the speed component in the direction of a mark. If the course deviation is {\textstyle \theta }







and speed over ground {\textstyle V_{o}}







, the speed component toward a mark:

{\displaystyle VMC,{\hat {y}}=V_{o}cos\theta }









If the course is directly towards a mark, *VMC *will be identical to speed over ground (SOG). An ordinary GPS unit will, if it indicates a VMG measurement, of necessity be *Velocity Made good on Course*. Measurement of wind speed and direction, in addition to boat speed and heading, is required to calculate a real *VMG* reading."

_If a mark is exactly currently in the direction of the wind, *VMC *will be the same as *VMG*. As the direction towards a mark deviates with the direction of the wind, VMC will deviate from true VMG, and will be less useful to use for the purpose of optimizing sailing performance."_


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## pdqaltair

colemj said:


> Inner headsail telltails just starting to break or flutter is exactly where you want the sail trimmed/boat pointed. For the main, you want the top one or two breaking ~50% of the time.
> 
> Mark


This. In flat water conditions this is what "steering to the tell tales" looks like.


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## pdqaltair

SchockT said:


> Im the real world VMG has everything to do with your destination. In fact most GPS systems won't even display a vmg number unless you have an active way point.
> 
> Sent from my SM-G981W using Tapatalk


Yes... and no.

The VMG to windward is the VMG on a strictly windward leeward course. However, the best VMG to a point that is to one side of straight up wind but still in the tacking zone is often given by a "Wally" angle. The old school way of puting this was that you foot on the lifted tack and pinch on the headed tack, but just 5 degrees or so. A close look at a speed polar will show this. So yes, strictly speaking, you want to know the VMG to a course, since you probably are not headed exactly to windward. Odly, you do not want the VMG to a point, because that keeps changing, which I think is obviously not want you want.

The best angle also changes with both persistent or even oscillating windshifts. That's racing.


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## Ninefingers

What do lifted and headed tacks mean? Is it when one is 30 degrees to a mark and the other is 60 degrees for example?


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## Jeff_H

Generically, the term VMG is not necessarily related to the optimal beating or running course. But in these days of advanced instrumentation, that is not how the term is applied. These days the term VMG is applied to optimal wind angle for beating and running.

Going back to basics, the term VMG as it was applied starts with the physics definition of Velocity, which was the combination of speed and in a specific direction, essentially a vector analysis. The 'made good' part in the days of dead reckoning navigation, was the speed and distance towards what we now call a waypoint.

In that more traditional definition, VMG merely was the speed in the direction you are trying to go.

But as integrated and computer embedded instrumentation systems came into use, specific abbreviations were adopted to distinguish between instrument measured wind speed and direction, and speed through the water generated data vs. GPS generated data.

In that context, the abbreviation VMG was assigned to Velocity Made Good based on instrument measured wind speed and direction and speed through the water.

VMC, a term that did not exist before electronic navigation, was created to distinguish VMG generated through GPS data from VMG derived from wind and water measurements.

In racing I use both because VMG does not include any indication of leeway and current. Cruising, I put in a Route, and that spits out all kinds of data. I pay closest attention to COG, BTW, and ETA. Of the three, I optimize VMG through experimentation to see which course and sail trim provides the earliest ETA. As others have noted the optimal course will change with shifts in wind and current speed and direction.

Jeff


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## Jeff_H

Ninefingers said:


> What do lifted and headed tacks mean? Is it when one is 30 degrees to a mark and the other is 60 degrees for example?


In a properly laid out race course, the windward mark is precisely upwind of the starting line and leeward mark. In practice that almost never happens due to shifts in wind direction.

Typically, once the windward mark is no longer dead upwind of the start or leeward mark, sailing on an optimized course one tack will be aimed more closely at the next mark and that course is referred to as the favored tack.

Lifted refers to a wind shift that rotates towards the original wind direction, and headed refers to a wind shift that rotates away from the original wind direction.

Upwind the favored tack is the lifted tack (rotated towards the wind direction relative to the mark). Downwind the favored tack is the headed tack

Jeff


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## SanderO

Jeff_H said:


> Generically, the term VMG is not necessarily related to the optimal beating or running course. But in these days of advanced instrumentation, that is not how the term is applied. These days the term VMG is applied to optimal wind angle for beating and running.
> 
> Going back to basics, the term VMG as it was applied starts with the physics definition of Velocity, which was speed in a specific direction. The 'made good' part in the days of dead reckoning navigation, was the distance towards your what we now call a waypoint.
> 
> In that more traditional definition, it merely was the speed in the direction you are trying to go.
> 
> But as integrated and computer embedded instrumentation systems came into use, specific abbreviations were adopted to distinguish between instrument measured wind speed and direction, and speed through the water generated data vs. GPS generated data.
> 
> In that context, the abbreviation VMG was assigned to Velocity Made Good based on instrument measured wind speed and direction and speed through the water.
> 
> VMC, a term that did not exist before electronic navigation, was created to distinguish VMG generated through GPS data from VMG derived from wind and water measurements.
> 
> In racing I use both because VMG does not include any indication of leeward and current. Cruising I put in Route, and that spits out all kinds of data. I pay closest attention to COG, BTW, and ETA. Of the three, I optimize VMG through experimentation to see which course and sail trim provides the earliest ETA. As others have noted the optimal course will change with shifts in windspeed and direction.
> 
> Jeff


Precisely... things are changing as one sails... even with a steady/consistent wind... the current will change... and as you progress the bearing to the destination waypoint will change unless it is straight ahead and you are able to fetch the mark without changing your heading (unlikely),

So YES we scan the computed data on the plotter to inform sail trim, heading and so forth... when and where to tack or gybe. The entire process is dynamic and constantly changing... even if slightly. I suppose for races all this changes much faster as the marks are close and the wind angles change after making a mark.

This process makes sailing a mental challenge... or mental process as much or even more than a physical one. As I am not steering...,I use the AP and at most turn a course dial... all I do physically is sail trim or tack / gybe... which hopefully I don't have to do lots of...

For me sailing is actually MOSTLY a thinking/analysis exercise using instrument supplied data as well as actual in situ observations!


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## SchockT

SanderO said:


> I believe you are confusing velocity made good to a waypoint - and velocity made good on Course or *VMC*
> 
> "The term *Velocity Made Good* (VMG) is often confused with term *Velocity Made good on Course* (VMC), and often used interchangeably.[1][2] VMC is the speed component in the direction of a mark. If the course deviation is {\textstyle \theta }
> 
> 
> 
> 
> 
> 
> 
> and speed over ground {\textstyle V_{o}}
> 
> 
> 
> 
> 
> 
> 
> , the speed component toward a mark:
> 
> {\displaystyle VMC,{\hat {y}}=V_{o}cos\theta }
> 
> 
> 
> 
> 
> 
> 
> 
> 
> If the course is directly towards a mark, *VMC *will be identical to speed over ground (SOG). An ordinary GPS unit will, if it indicates a VMG measurement, of necessity be *Velocity Made good on Course*. Measurement of wind speed and direction, in addition to boat speed and heading, is required to calculate a real *VMG* reading."
> 
> _If a mark is exactly currently in the direction of the wind, *VMC *will be the same as *VMG*. As the direction towards a mark deviates with the direction of the wind, VMC will deviate from true VMG, and will be less useful to use for the purpose of optimizing sailing performance."_


I feel like the distinction you are making is a purely academic one for most people. In my world VMG has always been a number that represents the portion of your SOG that is in the direction of the mark or waypoint. Of course until my current boat I have never had full instrumentation to work with. I don't know if my instruments are displaying VMC and just calling it VMG or whether it is true VMG.

I have always paid more attention to vmg numbers when sailing downwind, particularly when flying an asymmetric since the fastest way down wind is usually not the rhumbline, and finding the best angles is more difficult.

Upwind has always been about sailing as high as one can while still maintaining good boatspeed. How high that is was usually determined by wind and wave conditions or tactical considerations more than instrumentation. The idea of sailing high on one tack and footing on the other if the weather mark is not directly upwind seems very strange to me. I come from the school of thought that says you never "spend" gains to weather unnecessarily. The weather mark might not be directly upwind at the bottom of the course, but the wind may very well shift before you get to the top. I would never foot off until I was near layline.

Of course most of my racing experience is "seat of the pants" using compass, telltales, knot meter and maybe basic GPS info. Perhaps racers who rely more heavily on their electronics do things differently.

Sent from my SM-G981W using Tapatalk


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## pdqaltair

SanderO said:


> ...For me sailing is actually MOSTLY a thinking/analysis exercise using instrument supplied data as well as actual in situ observations!


I REALLY want to turn your instruments off. The ghosts of iron men of old are offended.

(Just kidding , but I dare say most of us started sailing before any instruments, and we liked it. Sailing is an intentional anachornism. That, and you should be able to do this "math" in your head--that's sailing.)


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## SanderO

SchockT said:


> I feel like the distinction you are making is a purely academic one for most people. In my world VMG has always been a number that represents the portion of your SOG that is in the direction of the mark or waypoint. Of course until my current boat I have never had full instrumentation to work with. I don't know if my instruments are displaying VMC and just calling it VMG or whether it is true VMG.
> 
> I have always paid more attention to vmg numbers when sailing downwind, particularly when flying an asymmetric since the fastest way down wind is usually not the rhumbline, and finding the best angles is more difficult.
> 
> Upwind has always been about sailing as high as one can while still maintaining good boatspeed. How high that is was usually determined by wind and wave conditions or tactical considerations more than instrumentation. The idea of sailing high on one tack and footing on the other if the weather mark is not directly upwind seems very strange to me. I come from the school of thought that says you never "spend" gains to weather unnecessarily. The weather mark might not be directly upwind at the bottom of the course, but the wind may very well shift before you get to the top. I would never foot off until I was near layline.
> 
> Of course most of my racing experience is "seat of the pants" using compass, telltales, knot meter and maybe basic GPS info. Perhaps racers who rely more heavily on their electronics do things differently.
> 
> Sent from my SM-G981W using Tapatalk


Well yeah... this is basically "academic"... For example... the VMG is a computation that calculates the forward speed... with is to the direction of where the wind is. So for example say the wind is steady and I am close hauled as the wind angle is 30 deg.... and I am sailing 5 knots. If I head higher... the boat speed AND and the distance covered forward drops. As I sail higher... speed drops and when I as heading to the wind... I have no forward speed. If I were to fall off the speed would probably increase. And likely would increase until I was sailing a beam reach... and the wind would be on my beam... and I would never arrive at a windward destination. So your instruments can and do calculate what your speed is to windward (eye of the wind) as you change heading or trim. But this VMG calculation has no position destination. And if you are sailing to a specific point the VMC will be changing even if nothing else changes.... and finally your mark is on your beam... and if you were to hold your heading... the mark would be astern and you would have to sail down wind to get there.

A "race" calculator instrument will show true VMG as it uses wind angle, and boat speed... A GPS plotter which has no wind info (usually) will show things like TTG to waypoint or velocity made good to waypoint.... bit VMG to windward for example.


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## SanderO

pdqaltair said:


> I REALLY want to turn your instruments off. The ghosts of iron men of old are offended.
> 
> (Just kidding , but I dare say most of us started sailing before any instruments, and we liked it. Sailing is an intentional anachornism. That, and you should be able to do this "math" in your head--that's sailing.)


I love the information from my instruments... Part of the information to inform course I steer, sails plan, and trim, I use my tell tales and know how to trim / set the sails for the wind angle. My instruments show boat speed to .01 kts precision. It's likely not accurate but you can SEE a micro changes in speed. There is also a flag tick mark which indicates if boat speed is slowing, steady or increasing. In lighter air this is very helpful to get the boat moving as fast as it can.










You can see the tick at the lower left of the BOAT SPEED display which read 7.5... this is telling me that the boat speed is trending slower. True wind is calculated at 19.1 and apparent wind speed is 13.7 sailing a broad reach.

I am pretty tuned into the boat and can tell when it is in the groove or not.


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## johnsonjay17

Jeff_H said:


> In a properly laid out race course, the windward mark is precisely upwind of the starting line and leeward mark. In practice that almost never happens due to shifts in wind direction.
> 
> Typically, once the windward mark is no longer dead upwind of the start or leeward mark, sailing on an optimized course one tack will be aimed more closely at the next mark and that course is referred to as the favored tack.
> 
> Lifted refers to a wind shift that rotates towards the original wind direction, and headed refers to a wind shift that rotates away from the original wind direction.
> 
> Upwind the favored tack is the lifted tack (rotated towards the wind direction relative to the mark). Downwind the favored tack is the headed tack
> 
> Jeff


In a properly laid out windward/leeward course. As far as I am concerned a good race is beam reach both way baby. 😀

Signed crew on a boat with training wheels.


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## SchockT

johnsonjay17 said:


> In a properly laid out windward/leeward course. As far as I am concerned a good race is beam reach both way baby.
> 
> Signed crew on a boat with training wheels.


That is THE WORST kind of race! It is nothing more than a drag race!

Sent from my SM-G981W using Tapatalk


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## SanderO

johnsonjay17 said:


> In a properly laid out windward/leeward course. As far as I am concerned a good race is beam reach both way baby. 😀
> 
> Signed crew on a boat with training wheels.


requires a wind shift actually.... to sail a beam reach on reciprocal courses. Or you are sailing a close reach.... if the true wind is perpendicular to your course line... because the moving boat moves moves the true wind forward and it becomes the apparent wind,


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## johnsonjay17

SchockT said:


> That is THE WORST kind of race! It is nothing more than a drag race!
> 
> Sent from my SM-G981W using Tapatalk


That is a fun race when you are the fastest thing racing and we start a catchy up style race so we get to start almost dead last and pass everybody else
JJ


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## johnsonjay17

SanderO said:


> requires a wind shift actually.... to sail a beam reach on reciprocal courses. Or you are sailing a close reach.... if the true wind is perpendicular to your course line... because the moving boat moves moves the true wind forward and it becomes the apparent wind,


Some folks are way too technical 
Any thing from a close reach to a broad reach is close enough.


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## MarkofSeaLife

pdqaltair said:


> I REALLY want to turn your instruments off. The ghosts of iron men of old are offended.
> 
> (Just kidding , but I dare say most of us started sailing before any instruments, and we liked it. Sailing is an intentional anachornism. That, and you should be able to do this "math" in your head--that's sailing.)




I feel its safer for new sailors to learn the new methods not the archaic.

A few days ago I was told firmly that the 'basics are the same'. Nope, they are not.
The ghosts of iron men may well be affronted as their knowledge is now obsolete, but even they would have to respect the safety advantage of VMG, via GPS and plotter, than working out a dangerous current on paper.

Last year I did a run across the Alderney Race, a current that goes up to 9 knots, part of which goes over shallows strewn with rocks. At the critical moment - the absolute critical moment - my engine died in the butt and I had very little wind, a 5 knot current leading onto the shoals 1 nm mile away and boat speed way below 5knots. VMG was utterly critical. I feel that in that position pre-VMG I would have lost my boat... and maybe the lives of the 2 on board. My boat was pointed maybe 90 degrees off where I wanted to go. It was confusing, disorientating and could have been panic inducing. 
The Army teaches a similar thing to pilots who as using instruments in low visibility: The INSTRUMENT is ALWAYS right. As I understand it, the best pilots in cloud/mist/white-out can lose spatial orientation within 30 seconds without instruments.

I feel its time to allow the computer its rightful place in sailing 

Mark


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## Minnewaska

MarkofSeaLife said:


> The INSTRUMENT is ALWAYS right.


Close. It's "always trust your instruments". That's slightly different, as you must cross reference your instruments to insure they are all right (ie trust the right one). Being able to quickly identify an instrument failure is just as critical.

Back in the day, with vacuum driven gyroscopes, a gyro failure would spool down very slowly and your artificial horizon would slowly bank over, until it died. As you began to follow it, thinking you were adjusting to keep wings straight and level, you'd slowly enter a turn. Your heading indicator and turn coordinator would confirm the horizon was wrong. It's a guarantee you'd experience it in every simulator check ride.

Nevertheless, I completely agree that electronic nav can improve safety aboard a vessel. If it can take an airplane thousands of miles from runway to runway, without ever seeing a thing, it can certainly do a good job of guiding a boat at about half the speed of a bicycle.


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## SanderO

Minnewaska said:


> Close. It's "always trust your instruments". That's slightly different, as you must cross reference your instruments to insure they are all right (ie trust the right one). Being able to quickly identify an instrument failure is just as critical.
> 
> Back in the day, with vacuum driven gyroscopes, a gyro failure would spool down very slowly and your artificial horizon would slowly bank over, until it died. As you began to follow it, thinking you were adjusting to keep wings straight and level, you'd slowly enter a turn. Your heading indicator and turn coordinator would confirm the horizon was wrong. It's a guarantee you'd experience it in every simulator check ride.
> 
> Nevertheless, I completely agree that electronic nav can improve safety aboard a vessel. If it can take an airplane thousands of miles from runway to runway, without ever seeing a thing, it can certainly do a good job of guiding a boat at about half the speed of a bicycle.


It is unnerving to sail with 0 visibility... but it can be done with electronic instruments. Radar is mission critical. However when there is visibility your instruments will do all the calculations... and very very fast.... that you learned in navigation class about piloting and coastal navigation. Instruments provide data.... Skipper has to interpret and use the data... unless the boat has a GPS driven AP. The sailor still needs to select the correct sail and trim it properly to the wind angle and speed... Motoring without sails this is not an issue. Avoiding collision may likely require dodging a hazard and this usually will require human intervention.

Conditions are changing which complicates the calculations and decisions... especially in coastal waters with "traffic".,, making human monitoring, interpretation and intervention almost a necessity.


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## pdqaltair

MarkofSeaLife said:


> I feel its safer for new sailors to learn the new methods not the archaic.
> 
> A few days ago I was told firmly that the 'basics are the same'. Nope, they are not.
> The ghosts of iron men may well be affronted as their knowledge is now obsolete, but even they would have to respect the safety advantage of VMG, via GPS and plotter, than working out a dangerous current on paper.
> 
> Last year I did a run across the Alderney Race, a current that goes up to 9 knots, part of which goes over shallows strewn with rocks. At the critical moment - the absolute critical moment - my engine died in the butt and I had very little wind, a 5 knot current leading onto the shoals 1 nm mile away and boat speed way below 5knots. VMG was utterly critical. I feel that in that position pre-VMG I would have lost my boat... and maybe the lives of the 2 on board. My boat was pointed maybe 90 degrees off where I wanted to go. It was confusing, disorientating and could have been panic inducing.
> The Army teaches a similar thing to pilots who as using instruments in low visibility: The INSTRUMENT is ALWAYS right. As I understand it, the best pilots in cloud/mist/white-out can lose spatial orientation within 30 seconds without instruments.
> 
> I feel its time to allow the computer its rightful place in sailing
> 
> Mark


I'm not going to argue, but this is the funniest thing I've read in days... for most of us.

First, sailing is by it's nature an anachronism, and we love it for that. If you can't appreciate that the old ways, well, that's like a hiker that gets lost without his cell phone. I just can't understand that. When it comes to navigating around rocks, I get the value of GPS. I use it regularly when traveling on business and sailing at night or fog. But during the day... only when I know there are tricky rocks around. As for sail trim...

How could the boat be pointing 90 degrees off with such obvious tells as wind dirrection and swell? At any moment, a sailor should be able to instantly orient himself by looking in pretty much any direction. Disorientation, during the day, is ... inconceivable unless you have become so tied to the instruments that you have not noticed the wave dirrection. It does not change in 30 seconds. There was a compass. I admit I do not know thw specific situation and fog could have made it tough. But this is exactly the sort of situation where reliance on instruments is problematic. What if the problem had been a power failure? You'd have no chance. First and foremost, it is a sail boat, and you should need neither engine nor electricity. The course should have been in your head and a little quick visual trig should have told you the direction you needed to go. If a compass and some quick mental trig aren't enough you really shouldn't be there.

I firmly feel the best thing you can do for a new sailor is turn ALL of the instruments off until they can sail and trim by the wind in their hair, the tell tails, and the look of the wake. They should be able to navigate by compass, a visual look at the run through the water, and a few soundings and shore sights when feasible. Only after the basics are instinctive, do you allow the simplification of instruments.

You learn mental math before they give you a calculator. You learn to spell before you are given spell check. You learn geometry with a pencil before trig with a calculator. You learn to sail before you need instruments.

You also need to get your head out of the cockpit to see other boats, the approach of waves, and the look of a gust across the water. Instruments can't anticipate.

I know you disagree. That cool. Each enjoys their own style.


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## pdqaltair

And yeah, I've sailed in soup many times with no instruments. They didn't exist in a practical (affordable) way until I had been sailing 20 years.

Some days you don't go out. You know your limitations.
You navigate with hazards firmly in mind and give wide berth.
You stick to what you can be sure of and check your dead reconing at every chance.
You stand off, if need be.
You are acutely aware of waves and wind.
GPS is better. But it should be layered on top of basic skills, not used as a replacement. I know plenty of stories of people using instruments that still hit something obvious.


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## colemj

pdqaltair said:


> You learn mental math before they give you a calculator calculators were invented. You learn to spell before you are given spell check was invented. You learn geometry with a pencil before trig with a calculator pencil. You learn to sail before you need instruments for that were available.


Hehe. I fixed that to be more relative to many of us - especially MarkJ... 

BTW, isn't a compass an instrument? Or is there a dividing line between acceptable and unacceptable instruments for a beginner?

Shouldn't real sailors be able to sail and navigate only by the subtle refractive wave patterns from distant lands?

Mark


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## SanderO

All sailors learn to sail "the old way" and those they are taught "navigation" learn traditional DR ( I did) and THEN they may be introduced to electronic instruments.. aside from the basic depth and boat speed.


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## colemj

SanderO said:


> All sailors learn to sail "the old way" and those they are taught "navigation" learn traditional DR ( I did) and THEN they may be introduced to electronic instruments.. aside from the basic depth and boat speed.


You haven't been watching youtube lately... 

Mark


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## MarkofSeaLife

Our yacht club is dying.
It's probably the most prestigious in Australia.
It has no young people joining because it wants to teach kids the archaic way. Opti's et al.
But here is the Now. It's not the future, its now.


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## SanderO

colemj said:


> You haven't been watching youtube lately...
> 
> Mark


This is true... I am aware of the obsession with speed and noise... And I suppose many try to run before they can crawl or walk...


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## Minnewaska

MarkofSeaLife said:


> Our yacht club is dying.
> It's probably the most prestigious in Australia.
> It has no young people joining because it wants to teach kids the archaic way. Opti's et al.
> But here is the Now. It's not the future, its now.
> View attachment 138033
> View attachment 138034
> View attachment 138035


I agree 1,000%. I traveled in Europe, as a teenager, before cell phones existed. The only way my Parents even knew I was on the flight home, was when I walked off the jetway. Today's kids can't be out of the house, without their cell phone.

Before anyone gets self righteous that the next generation is defective, I don't agree. There is downside, for sure, but the network connectivity of my kids generation is incredible. Access to expertise at the tap of a device in their pocket, 24/7. Vitually everyone they've ever known is still accessible to them. It's powerful.

Kids don't want to sail the way we did at their age any more than we wanted to learn by crewing on a wooden square rigger.


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## Explorer

MarkofSeaLife said:


> Our yacht club is dying.
> It's probably the most prestigious in Australia.
> It has no young people joining because it wants to teach kids the archaic way. Opti's et al.
> But here is the Now. It's not the future, its now.
> View attachment 138033
> View attachment 138034
> View attachment 138035


A problem for all clubs in most traditional sports once kids turn about 16.
The trick is to get them started when they are 8 knowing you will lose most by 16 and get them back when they are 35 with kids of their own because they know it is something they can do with their kids, or at least do it at the same club and they want their kids to have the benefits that sailing brings.


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## SchockT

MarkofSeaLife said:


> Our yacht club is dying.
> It's probably the most prestigious in Australia.
> It has no young people joining because it wants to teach kids the archaic way. Opti's et al.
> But here is the Now. It's not the future, its now.
> View attachment 138033
> View attachment 138034
> View attachment 138035


I'm not sure I agree with that conclusion. Sure high performance boats are appealing to kids but that is nothing new. High speed sailing has been around for decades various forms but you can't throw a beginner sailor onto a foiling boat or even an old 420 or 505 before they learn the basics. Optimists and Lasers are ideal to start kids off in sailing because they are simple and stable. The junior sailing programs at both of my yacht clubs are very popular.

There are other factors that are contributing to decline of yacht clubs that have more to do with what they have to offer the adults, not the kids, but that is a discussion for another thread.

Sent from my SM-G981W using Tapatalk


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## Explorer

SchockT said:


> I'm not sure I agree with that conclusion. Sure high performance boats are appealing to kids but that is nothing new. High speed sailing has been around for decades various forms but you can't throw a beginner sailor onto a foiling boat or even an old 420 or 505 before they learn the basics. Optimists and Lasers are ideal to start kids off in sailing because they are simple and stable. The junior sailing programs at both of my yacht clubs are very popular.
> 
> There are other factors that are contributing to decline of yacht clubs that have more to do with what they have to offer the adults, not the kids, but that is a discussion for another thread.
> 
> Sent from my SM-G981W using Tapatalk


I think if you read my comment again you will see that I agree with you. Nowhere did I mention high performance boats. Start 'em young in Optimists, Sabots, Manly Juniors, Herons (with a parent skippering), or whatever your club uses. Have a pathway through to more exciting classes incl with spinnakers for those that stay with it. Give them great memories of fun with other kids at sailing. Almost all will leave sailing from 16 to 35, but hopefully they come back with their kids. I ran a very successful learn to sail for juniors and adults for 5 years at a dinghy club. That program, continued by others, has provided about 50% of current members. The club would be facing very high fixed costs per member if not for that program. It is essential to maintain a broad base of new young members even though the attrition rate is very high as once the downward spiral starts costs per member go up, discouraging both existing and new members. Getting grants is another important thing for community clubs, and having members prepared to volunteer and be supervised by other volunteers with more skills is also important.


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## SchockT

Explorer said:


> I think if you read my comment again you will see that I agree with you. Nowhere did I mention high performance boats. Start 'em young in Optimists, Sabots, Manly Juniors, Herons (with a parent skippering), or whatever your club uses. Have a pathway through to more exciting classes incl with spinnakers for those that stay with it. Give them great memories of fun with other kids at sailing. Almost all will leave sailing from 16 to 35, but hopefully they come back with their kids. I ran a very successful learn to sail for juniors and adults for 5 years at a dinghy club. That program, continued by others, has provided about 50% of current members. The club would be facing very high fixed costs per member if not for that program. It is essential to maintain a broad base of new young members even though the attrition rate is very high as once the downward spiral starts costs per member go up, discouraging both existing and new members. Getting grants is another important thing for community clubs, and having members prepared to volunteer and be supervised by other volunteers with more skills is also important.


Yes it was MarkofSeaLife's post I was disagreeing with.

Sent from my SM-G981W using Tapatalk


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## MarkofSeaLife

Explorer said:


> Start 'em young in Optimists, Sabots, Manly Juniors,


Manly Juniors were great boats for kids as they have a main, jib and spinnaker. Teaches them everything.

Need to go through the Opti's to lazers then to fast exciting boats earlier.


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## MarkofSeaLife

SchockT said:


> Yes it was MarkofSeaLife's post I was disagreeing with.


What? Moi? Impossible!!


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## Explorer

MarkofSeaLife said:


> Manly Juniors were great boats for kids as they have a main, jib and spinnaker. Teaches them everything.
> 
> Need to go through the Opti's to lazers then to fast exciting boats earlier.
> View attachment 138197


The other advantage of Manly Juniors that I realised too late was the self draining cockpit. A capsized Sabot was like a bath full of water and took a lot of coach time. My dinghy club was mainly Sabots then switched to Optis with spirals for teenagers with a bit of experience and adults. (Spiral is a like a small laser, ideal for those about 70kg) Club also sailed NS14's, Tasars, Heron's and assorted others including 14ft cats, mainly Maricats.

Manly Junior > Flying 11 > Cherub > Skiff (29er, 12ft, 16ft, 18ft, 49er) > Yachts would probably be the path I would suggest. I am at the (small) yacht stage and in the process of retiring from the foredeck.

My kids started in Herons with me (my first dinghy bought at age 39 when youngest was 7) after crewing on a friends yacht for 3 seasons on Sydney Harbour in my mid 20's). One then went to their own Heron (double trailer bought to take two to interclubs, States and Nationals, while the other went to Sabot then crewing on Flying 11's. Both finished around 16 but do occasional social sailing in their 30s.


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## SchockT

MarkofSeaLife said:


> What? Moi? Impossible!!


Nothing personal, I just think you need to look elsewhere for the cause of your club's decline! Are you RSYS?

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## Waltthesalt

Done a lot of racing. Upwind depends a lot on the wind, boat seas etc, Not reduced to a number rather winners have a sense for the boat. Hard describe. In heavy winds you may want to feather up. When the boat feels sluggish you may want to slacken off. The best learning I got was from an old salt who has us kids sail blindfolded.


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## Explorer

We have also used blindfold (well closed eyes to be more accurate) technique in NSW Heron Dinghys junior training camps for teenagers about 2000 to help them develop feel, also teaching them to change direction by changing trim of sails, eg mainsheet on harder and jib softer to go more to windward, main softer and jib harder to steer to leeward. Many also say that the best car racing drivers start young in go karts and develop a feel through the seat of the pants.


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## Explorer

SanderO said:


> VMG... is an instantaneous analysis of the boat's performance base on wind speed, angle and boat speed through the water,
> 
> "*Velocity made good*, or *VMG*, is a term used in sailing, especially in yacht racing, indicating the speed of a sailboat towards (or from) the direction of the wind.[1][2] The concept is useful because a sailboat cannot sail directly upwind, and thus often can not, or should not, sail directly to a mark to reach it as quickly as possible. It is also often less than optimal to sail directly downwind."
> 
> This has nothing to do with your chosen mark, waypoint or destination.


In the youtube video of the Americas Cup/Prada Cap race the dashboard on the video shows VMG. Do you thing they are showing relative to the next gate, the true wind or the apparent wind?


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## Explorer

Explorer said:


> In the youtube video of the Americas Cup/Prada Cap race the dashboard on the video shows VMG. Do you thing they are showing relative to the next gate, the true wind or the apparent wind?


I think I just saw a graphic on the race video which would confirm they are using VMG as being velocity in the direction from which the _apparent_ wind wind is coming. Look for the yellow arrow line extending from the front of the boats at about 50mins 20 secs into the video.


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