Polar for the laser

I kinda doubt it, but will leave it for others to say.

But your terse question begs the follow on question, why do you want polars for a laser?
 
gregson said:
Does anyone have a polar for the Laser full rig?

TIA
Peter
Click to expand...
Do you mean a Polar coloured sail as in the brochure below?
 

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  • Laser Brochure.jpg
    Laser Brochure.jpg
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OK, I admit it, that diagram piqued my interest. But it raises as many questions as it answers. How do you prepare a polar diagram for a planing dinghy? What weight crew do you use? How hard is that crew hiking out in the calculations? Small dinghies are extremely subject to wave action, but polars are notorious for ignoring the impact of waves on the craft being evaluated.

It was interesting to see that in the picture shown, basically in anything F4 and above, the best VMG is as far DDW as you can go, while keeping the boat mast-up-board-down, which of course pretty much matches up with experience on the racecourse. Gybing downwind is a light-air tactic.
 
Those lines look like weather channel hurricane track marks to me.....but I was an english major.
 
ok... I'll raise my stupid hand... so in this chart, 180 degrees is ddw, and the bars out from the center are velocity... so at f5 (25k), the laser's best speed is a broad reach, somewhere between 105 and 135 degress off the wind?

bjmoose, I have no idea how you concluded that you did from this chart....
 
At former the drLaser.org, at the Menue "Boat Handling", has been a report about polars, under the headline "Polars, Targets & Steering methods".
 
pez said:
ok... I'll raise my stupid hand... so in this chart, 180 degrees is ddw, and the bars out from the center are velocity... so at f5 (25k), the laser's best speed is a broad reach, somewhere between 105 and 135 degress off the wind?

bjmoose, I have no idea how you concluded that you did from this chart....
Click to expand...

I'm guessing you are wondering how bjmoose concluded that DDW was the fastest angle to sail downwind on the polars

For both upwind and downwind, draw a perpendicular line to the 0/180 degree lines, where the polar touches the that line farthest from the center is the best VMG towards upwind or downwind... (this assumes the course is Windward/Leeward - the concentric circles around the center represent boat speed, not wind speed.)

The attached PDF from Ockam may explain it a little more clearly ;)

As bjmoose also correctly pointed out, these polars for the Laser don't take into account waves.. So the game changes once you are sailing downwind in waves
 

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  • SplainPolars(2).pdf
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Thanks, folks. The reason that I want the polar is because I am having to teach myself to sail a Laser. I'm 57. While I am quite happy to sail with/against the kids, I am at work when they are in sailing school and sailing. I don't have other Masters Laser sailors to compete with. So I need to know just how fast the boat can go when properly sailed so that I know if I am getting close to good.

Practicing without a focus or a goal is merely entertainment.

Thanks for your help.

Peter
 
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