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boomup.jpg

We've discussed the advantages of moving the boom way above center line for many of the new, ultra wide big boats. But does it even work for boats like Nashua ah W.46  built at Rockport Marine? Discuss.

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I have done that for years with the Ensign in heavy air. Keep the Vang on a little and when it’s time to dump some air, easing the main let’s some air out at the top without letting the boom up and losing power and sail control. Plus, the boat has a pretty tight sheeting angle on the jib.

I think that’s what I do...

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If you do the math, the drive generated is a vector that should go forward, otherwise the boat would not.

image.png.8b38473c540ccefcdb70e57c215f180c.png

So in order to keep going forward if the main is hooked to windward,  the loss of drive generated from the main due to the vector going sideways, is compensated by the more efficient head-sail use.  The slot will be opened up and the sail plan can be carried a few knots more because it is not back-winding the main.

If you don't believe that it de-powers the main, try doing in in light air when you are looking for drive and see how you go.  Or, try dragging the boom to windward on a cat rigged boat ... no heady.

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I have heard the same thing,  that trimming the boom above centerline can sometimes be fast.  It has not worked for me.  It is all about sail shape.  Trimming past the centerline should mess up the airflow on the bottom of the main.  If the vang is not on hard enough, over-trimming past the centerline may close the top so the twist appropriately.  I would try more vang to close the top, still leaving twist, just quiet it down and keep the top working and have the bottom of the main still driving.  The vang and mainsheet for twist and boom position, the outhaul, cunningham, and backstay, to flatten the main.

We all know talk is cheap from the peanut gallery.  I am knee deep in empty shells.

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  The jib is trimmed quite close on the foot, but the leach is quite open - so I think that boom above center is the only way to keep the main full

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Whatever makes the boat faster than the competition. Winning racers are not computing force vectors or vortex shedding fields in their heads while trimming. If boom above center is faster so be it. Might be alleviating rudder loads, might be to open the mythical slot, might be for any number of obscure reasons.

The boom above center still leaves nearly the entire leech below the centerline, for whatever that is worth. Plus the lower aft corner of the main might be the most useless part of the sail anyway given leakage underboom, updraft, apparent wind twist, wind force, whatever. The upper half of the main seems to be the working part to me. That’s where my attention is focused.

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The most deflection of wind from the head-sail is at the foot.  If the main is dragged away from the lowest part of the slot so the it is not back-winded, that could be faster in a narrow wind range.

This did work on my boat when using the cruising wardrobe with a baggy furling genoa just before sail had to be shortened.  Dragging the boom to windward was a way to stop the main turning inside out.  At those times the boat was getting dragged along by that heady with the main at least not flapping about causing drag.   If this is done while the main is behaving itself and you are still looking for more power, the opposite will happen.

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See previous discussion on this topic.   Think flaps down on a jumbo.  High lift, high drag... 

Close hauled the sail plan works as one foil.   It's useless thinking about the main trim on its own.  It's even more useless showing some vector diagram of an asymmetric solid sail without slots. 

 I would imagine would work fine for pretty much any boat that is relatively easily driven up wind.   Fat slow block of flats maybe need not apply 

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I think the Ed isn't paying much attention either.  The last discussion included everything from etchells to ior bathtubs. 

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My two cents:  The answer is at the top rather than at the bottom.  

One of the big killers is induced drag, ie the tip vortex created at the top of your main.  If you can make the pressure difference at the top of your main as small as possible, your drag will be significantly reduced.  If air is going over the top of your main, you are dragging air with you.

So what we want is a twist that releases the top while the lower parts of the main is sheeted well in, creating a lift for your headsail.
To accomplish this we lift the boom across the centerline while at the same time having a little bit less tension on the sheet.  More twist at the top.
A fathead will contribute to this by design because the top is "weaker".

If you look at a boat that has lifted the boom like this from astern you will see that the leech of the main is below the center/backstay a fairly short way up from the boom.

Balancing the different effects of the flow over your sails will differ from boat to boat I would guess.

In the Sun Fast 3200 we are sailing, lifting the boom works like hell.

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1 hour ago, Spoonie said:

It's even more useless showing some vector diagram of an asymmetric solid sail without slots. 

Unless you are challenging Newton, the vectors are valid.

If you are talking about the diagrams in #5, that's not a solid sail.

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So I've been having this perpetual fight with my mainsheet trimmer about not having the boom above CL.  It always feels slow to me when we get the boom anywhere at or just above CL.  

I'm going to do some more speed testing this summer to see if I can actually quantify where I'm right or not.  So for this "Boom above CL" fad - what wind conditions is it typically best in?  Is having the vang on required to make this work correctly?  How hard on?  IOW, what shape am I going for to achieve this?  Is the overall shaped a twisted main leech shape for a fairly flat straight leech? 

Would this technique apply to a typical sportboat like a J70 or a Melges24? 

Thanks in advance!

BTW - what thread was this more indepth discussion in referenced above?  I can't find it.

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14 hours ago, Snaggletooth said:

Hi, Ime Snaggy, and I halve trimmed my maine waye aboove centreline.......                 :)

Yeah, so you’ve been East of Penobscot. You make it sound like a big deal. 

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13 hours ago, yikes said:

i dont think it works for boats built in rockport maine.

As Snaggles said, you have to be East of Eggemoggin. 

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6.36 kts at 43 twa looks a bit slow for a yacht of that length in the wind she appears to have. I’d say less than optimal trim, but I’m guessing.

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As mentioned above, looking at any sail in isolation ignores the way the whole sailplan works as a wing. With the very tight jib sheeting angles (4 degrees!) of the TP52 /  Maxi 72 types, boom over center in lighter air works because it keeps the slot open. It only works like this if the sails, hull and foils are really refined for high performance and the driver has skills.  If your boat won't sail upwind with VB near TWS, it's probably not the right mode for you.

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I noticed during the AC Bermuda races, the Kiwis especially 

trimmed that solid main well above center line.  

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Only a few feet above the boom, the leech is not above centerline. I am guessing that the foot isn't optimally trimmed, but the overall sail is close.

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19 hours ago, Editor said:

boomup.jpg

We've discussed the advantages of moving the boom way above center line for many of the new, ultra wide big boats. But does it even work for boats like Nashua ah W.46  built at Rockport Marine? Discuss.

it looks like they've flattened the main as hard as they could with the outhaul and cunningham, jib looks pretty flat, maybe they're trying to de-power the boat..

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That jib is not flat, and that hull actually needs more heel.

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48 minutes ago, Grande Mastere Dreade said:

it looks like they've flattened the main as hard as they could with the outhaul and cunningham, jib looks pretty flat, maybe they're trying to de-power the boat..

 

Huh?  That's about as powered up as it gets!  You depower by dropping the boom down, and easing the vang to twist off the Main top.

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on dragons it is usually on the centreline. with dragons, the jib is speed, the main helps with pointing. same on the 8mr's

 

Pedro_everyone_WEB.jpg?ext=.jpg

 

dragon-worlds-race-01-ph-max-ranchi-10.j

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21 hours ago, Editor said:

boomup.jpg

We've discussed the advantages of moving the boom way above center line for many of the new, ultra wide big boats. But does it even work for boats like Nashua ah W.46  built at Rockport Marine? Discuss.

Clear the answer is no. They are only doing 6.36 knots.

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1 hour ago, billy backstay said:

 

Huh?  That's about as powered up as it gets!  You depower by dropping the boom down, and easing the vang to twist off the Main top.

yes, that's how I do it too...   but based on what Longy said just after that the boat needs more heel, they seem to be pinching the hell out of the main and keeping the boat flatter and just cruising along which accounts for the foredeck sleeping on the job..   as usual.     and the guys wife is driving , gingerly it seems, which probably accounts for the lack of perfection and speed in the picture..   speculate all you want, as it's been pointed out..

It's slow..

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28 minutes ago, JMOD said:

 

dragon-worlds-race-01-ph-max-ranchi-10.j

That is a great shot.

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Dragon's not a good example here - they have overlapping genoas, so cannot trim the jib tight enugg to to require main above centerline

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StraightLeech.

Works for square top mains. To spill the wind at the top. Not sure about triangular mainsail. (Rambler88 at the start of the Bermuda Race).

20180615_160801_resized.jpg

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48 minutes ago, longy said:

Dragon's not a good example here - they have overlapping genoas, so cannot trim the jib tight enugg to to require main above centerline

Solings may be a better example: Non-overlapping, self-tacking jib. They sheet the boom blok-on-block to the centerline and then leave it there until the upwind mark. It results in  a brutally narrow groove, but, yea...

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12 minutes ago, 10thTonner said:

Solings may be a better example: Non-overlapping, self-tacking jib. They sheet the boom blok-on-block to the centerline and then leave it there until the upwind mark. It results in  a brutally narrow groove, but, yea...

You saye "narrow grove", howe abote effectieve slotte?  Tackes alle and digges alle!                      :)

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Looks like the boat is full of sailmakers who only make and trim sails one way.  This works on a minimaxi so it must be right for this old tub. 

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20 minutes ago, Alcatraz5768 said:

Looks like the boat is full of sailmakers who only make and trim sails one way.  This works on a minimaxi so it must be right for this old tub. 

assumptiones, assumptiones, assumptiones.........                        :)

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I think this works best on boats with a lot of power in the sail plan, easily driven hulls and very narrow sheeting angles.  They can afford to lose a bit of power in the main in order to gain a degree or two of point.  Hence why we see the TP 52's doing this a lot.   

In the case of the boat in the picture, it has a very narrow sheeting angle, and it looks like a pretty good breeze, so they might be able to get away with this.  I'd be surprised if it was an efficient way to sail upwind if the boat has a traditional underbody.

The other factor in this is the keel, which might stall if the boat is going too slow in this mode.  You would have to build speed first, then go into this mode. 

It won't work on every boat and it won't work in all conditions.  I can sail like this all day on my 6kt shitbox if I only want to go 4 kts and take a lot of leeway due to keel stall. 

 

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7 hours ago, Alcatraz5768 said:

Looks like the boat is full of sailmakers who only make and trim sails one way.  This works on a minimaxi so it must be right for this old tub. 

Yes and because they stitch or glue up sails they believe they know more than everyone else about everything. 

Could it be some out-gassing from the sail cloth?

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4 hours ago, Alcatraz5768 said:

look at the dude on the foredeck. sailmaker for life  

Is he taking photos with his phone?

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23 hours ago, random said:

Unless you are challenging Newton, the vectors are valid.

If you are talking about the diagrams in #5, that's not a solid sail.

Nothing wrong with the physics, the scenario and your description linking back to cat rigged boats is completely irrelevant.   

"winged sail" it says in the description.   Ie solid. 

Go find some flow diagrams of slotted wings 

EDIT: here are some nice ones. 

http://cfd2012.com/types-of-flaps.html

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13 hours ago, longy said:

Dragon's not a good example here - they have overlapping genoas, so cannot trim the jib tight enugg to to require main above centerline

Should still work.   The pics shown here are of dragons in moderate to heavy air.   Both pictures they are depowering the rig 

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1 hour ago, Spoonie said:

winged sail" it says in the description.   Ie solid. 

It also says "Fabric Sail"

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1 hour ago, Spoonie said:

Go find some flow diagrams of slotted wings 

Nothing to do with the discussion in this thread.  The OP is about traditional fabric sails on traditional booms.

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16 hours ago, JMOD said:

on dragons it is usually on the centreline. with dragons, the jib is speed, the main helps with pointing. same on the 8mr's

 

Pedro_everyone_WEB.jpg?ext=.jpg

 

dragon-worlds-race-01-ph-max-ranchi-10.j

+1...missed this thread and messed up...did with 110, Ensign and was great...I recall, as doing was sort of difficult to do and hold.

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16 hours ago, Grande Mastere Dreade said:

yes, that's how I do it too...   but based on what Longy said just after that the boat needs more heel, they seem to be pinching the hell out of the main and keeping the boat flatter and just cruising along which accounts for the foredeck sleeping on the job..   as usual.     and the guys wife is driving , gingerly it seems, which probably accounts for the lack of perfection and speed in the picture..   speculate all you want, as it's been pointed out..

It's slow..

Also makes sense to me...late as I are...

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3 hours ago, random said:

Nothing to do with the discussion in this thread.  The OP is about traditional fabric sails on traditional booms.

bj 

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It's all situational. Sometimes the ability to go higher upwind than your competition, or getting to the mark has huge advantage. That is possible in flat water and "designer wind" 10-15 kn breeze. When your keel is producing max lift in max upwind peed, with constant ideal pressure, minimal drag and max righting. The boom above centerline is like fifth or sixth gear. That's fine if you want to take quarter to half knot penalty of boatspeed for other gain (height).

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1 hour ago, SpongeBob said:

bj 

I missed it again. And, why I wonder...? Amen!

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8 hours ago, random said:

Nothing to do with the discussion in this thread.  The OP is about traditional fabric sails on traditional booms.

Sigh...   OK well, whatever... 

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15 hours ago, random said:

Yes and because they stitch or glue up sails they believe they know more than everyone else about everything. 

Like an asphalt layer interpreting climate change science?  Or the melting point of steel in burning buildings? 

When you have actually won a sailing race get back to us.

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Sheeting the mainsail above the centreline is a tool used by poor helmsmen who can't steer without weather helm.

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More sigh... 

I was going to walk away but I can't help myself here.   I'm going to start by saying y'all should watch this video from 1938 (yes 1938) 

Now yes it is a solid wing of an airplane and well sails on booms are not solid wings on air planes but well... whatever.

Back to the link I posted earlier, there's a really nice visual in the last picture:

3668347.png?855

Basically what happens here is as the AoA of the trailing flap increases, the flow starts to bifurcate and whip around the front of the foil.  If there was no foil in front, then as it whips around with higher velocity, it would probably separate and you just get a bucket load of drag as the video above shows.  But there is a foil in front so the front foil helps to keep the flow attached over the back of the back foil.  if that slot wasn't there and it was one continuous foil, then you probably also get separation (i.e turbulence and drag)

That point of bifurcation on each foil is the point of highest pressure on that foil.  So by having this series of flaps and slots, you can increase the pressure under the wing, with increased flow attachment on the top, higher AOA, more lift, and less drag.  

There is a point where this stops working and that's where you can no longer maintain attached flow across the outside of the wing.   

So what about boats?

On a yacht, the jib acts as that leading foil helping to keep the flow attached to the back of the main.  As long as you can keep flow attached to the back, you can in theory keep winding that main to windward.  In doing so, you move the high pressure point further aft in the sail and further accelerate the flow across the back of the main as flow bifurcates from the front of the main and around the front of the mast.

An interesting experiment would be to put a whole bunch of tell tales around the front of the main and mast about 1/2 m above the boom and see if you can see the contra flow around the front of the mast.

Now as you go towards the hounds, the jib gets progressively smaller relative to the main so the main acts more and more like a cat rigged boat.  Cat rigged boats, without a slotted flap on them somewhere, don't like high AoA without a lot of drag, and so without twist, the mid and top of the sail will start to stall.

Overlap vs Non-Overlap

To me, this is no-brainer for boats with non-overlapping jibs in light to moderate airs.  As long as you can keep the flow across the back of the main going.  Overlapping rigs it should still work I would think but you'd have to get the trim right on both sails, and I think it would look more like this:

155219.png?855

Some benefit, but not as much as having the slot there.  

Bathtubs vs Rocketships

To me, for any easily driven hull form, old or new, upwind this is a no brainer in light to moderate and flat waters.   I think the challenge here will be maintaining flow.  You need to maintain flow over both your keel and rig packages.  A lightweight boat in sloppy water may struggle.  An old long, heavier boat with a big chorded keel may actually fair better.  I don't know.  Slow fat bathtubs I'm not so sure but should probably still work in flatter water I would think.  If the boat pounds to a stop then that's a different story, you need to reattach flow to everything.  IMHO that's where the slow bathtubs will suffer

In Short

This is not about trading height for speed, it's about milking that extra few % out of your rig package albeit within a very small groove. 

You don't get height by simply pointing in that direction, you get height by buying it with flow over your rig and keel (ie. speed).  boom to windward helps give you that bit of extra camber out of your rig in the bottom 1/3rd as a whole package giving you more lift with roughly the same drag profile (as long as you keep flow attached).  It stops working when either the breeze picks up, you can no longer keep flow attached, or you become overpowered and you need to drop the boom down.  

As to lazy helmsmen, well, if the helmsman has to work then you are doing something wrong.  Yachts work because a balance of forces. If you are fighting against those forces then you are putting the handbrake on somewhere.  Upwind you want to create a neutral to semi positive feel to the helm.  Boom angle is one of the tools at your disposal for doing that.  Use it or not, I don't care.... 

And finally...

If you want to argue I'm wrong, go fire up Java Foil, Sail7 or similar and run some simulations.  I guarantee you that's what the big programs have done.  Theory is nice and all as well, so back it up with some practical on the water testing.  Again guarantee that's what the big programs have done.  

Will it work for your boat? I don't know, but I can certainly tell you why it *should* work and where it may not

Cheers
Craig

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19 hours ago, dash34 said:

I think this works best on boats with a lot of power in the sail plan, easily driven hulls and very narrow sheeting angles.  They can afford to lose a bit of power in the main in order to gain a degree or two of point.  Hence why we see the TP 52's doing this a lot.   

In the case of the boat in the picture, it has a very narrow sheeting angle, and it looks like a pretty good breeze, so they might be able to get away with this.  I'd be surprised if it was an efficient way to sail upwind if the boat has a traditional underbody.

The other factor in this is the keel, which might stall if the boat is going too slow in this mode.  You would have to build speed first, then go into this mode. 

It won't work on every boat and it won't work in all conditions.  I can sail like this all day on my 6kt shitbox if I only want to go 4 kts and take a lot of leeway due to keel stall. 

 

This boat has a blade rudder and a fin keel, but a bit more rocker than the most modern boats and the fin is much lower aspect ratio than most modern race boats, so not as quick, but fairly efficient, and a bit more forgiving against stalling. And above the waterline the hull has traditional shape with overhangs. I don't know what the real wind speed is, what their polars are, whether this works well, or whether they are pinching a little for some tactical reason.

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On 6/16/2018 at 3:54 PM, JMOD said:

on dragons it is usually on the centreline. with dragons, the jib is speed, the main helps with pointing. same on the 8mr's

 

Pedro_everyone_WEB.jpg?ext=.jpg

 

dragon-worlds-race-01-ph-max-ranchi-10.j

Don Street: “A wooden Dragon is like a beautiful woman; the sex appeal of a fibreglass Dragon is the sex appeal of a refrigerator”.

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What is so important about this so-called centerline? The line thru the backstay on an upwind boat is not the direction the boat is traveling thru the water. So is this whole discussion is perhaps based on an arbitrary (irrelevant) line? And the drawings misleading. Compare the boom to the direction thru the water...

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1 hour ago, daddle said:

What is so important about this so-called centerline? The line thru the backstay on an upwind boat is not the direction the boat is traveling thru the water. So is this whole discussion is perhaps based on an arbitrary (irrelevant) line? And the drawings misleading. Compare the boom to the direction thru the water...

Well you also have to consider the rig package as a hole has it moves through the air as well and not just the entry and exit flows. 

If you look at the angle of the boom on those maxis, if they're crabbing side wise that badly that it's now on center line, I'd be very surprised.  Mind you, the angles on some are less extreme:

25701-1-1000.jpg

but that's still what, 5 or 6 degrees at least?  Do they really have that much leeway?   The shadow helps you follow the curves though.  Trace the jib flow out, around, and past the leach of the main.  

The only thing that matters is the lift & drag the whole rig package generates relative to the boat.   Does the rig create more or less lift in this configuration? does it create more or less drag?  if you can increase lift with the same or less drag then win!   The big programs might be able to get away with it more than pleb boats because they've stripped so much other drag out of the rig through sail, mast, rig, that they can suffer a little more from the trim for extra lift and still get forward drive.  I don't know.

IMHO it's kinda like the discussion on overhangs.  Overhangs have to be doing work for them to be effective otherwise it's just surface drag.   how much work is your leach doing?  could it be doing more or are you just dragging it through the air?

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The few degrees of leeway are what give the underwater foils an AOA to do their work. The leeway for such lift is not a bad thing. It is the genius of modern hulls that they are actually designed to crab efficiently thru the water: round bottoms. Five degrees leeway for the foils might be reasonable...I wouldn’t pretend to know.

Whatever is faster than the other boat is all that matters. Not some arbitrary geometric rule.

That pic above shows some amazing sails and trim. Implies a rather easily driven hull, no?

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On 6/16/2018 at 11:51 PM, Snaggletooth said:

You saye "narrow grove", howe abote effectieve slotte?  Tackes alle and digges alle!                      :)

The slot is pretty much built into a Soling rig. (I always wondered why the experienced guys told me to ignore the traveller but just sheet the main to the center and leave it there but was afraid to ask. I thought a little more twist would have set her up to a little wider groove...) You can point these things incredibly high. But one degree too high and it feels like you threw an anchor. 

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I have admitted to dragging the boom up in very specific conditions, like controlling main back-winding.  But the conditions of the maxi in post #56 would not have been those conditions.  I can see that with the headsail sheeted inboard so far that they feel they have to, to clear the slot, it must be tempting.  If they are pinching to compete for water then ok.  Not convinced the VMG would be improved though.

Sometimes this looks like the old "if I pull harder on the strings it will go faster".

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2 hours ago, daddle said:

Whatever is faster than the other boat is all that matters. Not some arbitrary geometric rule.

That pic above shows some amazing sails and trim. Implies a rather easily driven hull, no?

Yeah, but there are a lot of easily driven hulls out there, especially upwind below hull speed.   

As per my comment above,  I'm not sure it is limited to such boats but the effects might be more pronounced.  Small amounts of lift probably makes a big impact if you've stripped all the drag out of your rig too. 

The north etchells tuning guide has the boom 40mm above center in light winds with a straight, if not hooked leach. If those are real world numbers then it's pretty subtle.  Even the 72 above is pretty subtle... I tried looking at the Ac cat wings but perspective is everything. 

 I can get mine 100mm - 150mm or so above centre with the top batten just flicking open (late 90's IMS 30'er).  That seems to be pretty quick for me up to about 8-10 on flat water.  I trim the jib full if not hooked with the leads in hard.  I pretty much discovered it by accident one day but didn't think anything of it as being weird. 

*shrug* someone would have run it through a computer and backed it up with trials I'm sure 

 

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7 hours ago, Svanen said:

Don Street: “A wooden Dragon is like a beautiful woman; the sex appeal of a fibreglass Dragon is the sex appeal of a refrigerator”.

Thanks...Svanen. The Dragon glass or wood is the max, to me...always loved 'em.

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3 hours ago, random said:

I have admitted to dragging the boom up in very specific conditions, like controlling main back-winding.  But the conditions of the maxi in post #56 would not have been those conditions.  I can see that with the headsail sheeted inboard so far that they feel they have to, to clear the slot, it must be tempting.  If they are pinching to compete for water then ok.  Not convinced the VMG would be improved though.

Sometimes this looks like the old "if I pull harder on the strings it will go faster".

They do it to make the boat heel more so more water comes over the deck. More spectacular for the TV viewers. It's a conspiracy between the TV networks and the Farr office.

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14 minutes ago, LB 15 said:

They do it to make the boat heel more so more water comes over the deck. More spectacular for the TV viewers. It's a conspiracy between the TV networks and the Farr office.

Have all the maxis with booms up had black decks? There has to be some sort of "thermal lift" effect there surely 

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With a narrow fin keel, getting enough lift can be done with extra leeway, without the penalty of carrying extra skin friction around the whole course.  so designing a boat that can powered up by sailing with extra leeway may be the fastest way around the track

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In my opinion, raking the mast forward a little (as shown in the picture) is also beneficial for the Dragons.

Star boats do it regularly and succesfully.

dragondrop.jpg

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Yes, but that is downwind and that system is built in. the boom on centreline is upwind. here they lost the backstay and runners from the look of it. this much rake used to be possible, till they brought it back to 5cm movement at deck level.

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20 hours ago, MelbourneA31 said:

Sheeting the mainsail above the centreline is a tool used by poor helmsmen who can't steer without weather helm.

You are joking, right?

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16 hours ago, daddle said:

What is so important about this so-called centerline? The line thru the backstay on an upwind boat is not the direction the boat is traveling thru the water. So is this whole discussion is perhaps based on an arbitrary (irrelevant) line? And the drawings misleading. Compare the boom to the direction thru the water...

yeah,.exactly.

we bring the boom up to control twist and to free up the exhaust in the slot

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On 6/15/2018 at 6:50 PM, random said:

If you do the math, the drive generated is a vector that should go forward, otherwise the boat would not.

image.png.8b38473c540ccefcdb70e57c215f180c.png

So in order to keep going forward if the main is hooked to windward,  the loss of drive generated from the main due to the vector going sideways, is compensated by the more efficient head-sail use.  The slot will be opened up and the sail plan can be carried a few knots more because it is not back-winding the main.

If you don't believe that it de-powers the main, try doing in in light air when you are looking for drive and see how you go.  Or, try dragging the boom to windward on a cat rigged boat ... no heady.

Now my head hurts!

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On 6/17/2018 at 9:58 AM, Kapteeni Kalma said:

 max upwind peed,

You're all wet.

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On 6/17/2018 at 4:26 PM, LB 15 said:

Like an asphalt layer interpreting climate change science?  Or the melting point of steel in burning buildings? 

When you have actually won a sailing race get back to us.

 

The burning point of jet fuel?

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8 hours ago, Grande Mastere Dreade said:

 

The burning point of jet fuel?

Yep LB totally loses the plot every now and then.  We ignore it.

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