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If a higher sail generates more power, then...

Weston

Active Member
Something has been puzzling me as I read about recommendation fired rigging a Sunfish for racing vs. recreational sailing.

If a higher sail generates more power, then why do I see the halyard attached so high (thus the sail is low) for nearly all racing sunfish? I understand that in High winds, keeping the sail closer to the deck reduces the likelihood of bending a mast. However, in light winds why wouldn’t sunfish racers mount the sail as high as possible to maximize the power when there is no risk of bending a mast? Or is this what sunfish racers are actually doing and I just have not observed it?
 

danpal

Active Member
I believe they are already doing this. This is why you have an gooseneck that's adjustable. You can move the gooseneck along the spar depending on wind conditions.
The goosneck can be moved forward and back depending on windspeed. For light air, it is moved forward, sometimes as close as 12 inches from the tack, so that the sail is canted up. In heavy air it is moved back, to the point where the bottom spar becomes parallel to the deck, up to 24 inches.

Halyard and Gooseneck position
 

Sailflow

Active Member
 
A higher sail does not by itself generate more power. Only a bigger sail, or adjusting sail trim, can do that.

In light winds, you can sometimes reach wind that is above the water, by having the sail as high as possible, even when it is dead at water level.
But in higher winds, where most big races happen, a higher sailplan has several disadvantages:

1) it creates a bigger lever arm, which you must counteract with your weight (by hiking out).
2) it can make it harder to sheet in to the centerline of the boat
3) the air rushing underneath the lower spar creates turbulence. Keeping the sail lower, and closer to the deck, reduces it.

In theory, you should be able to get more power in low wind, by raising your rig up high and grabbing clear air that may live up there.
But in any hiking conditions, you want to keep the rig low, or you will not be able to keep the boat flat.

Note: this is different than high aspect sails, which achieve better performance because they have a longer leading edge for the same sail area, but generally need battens. The super sunfish is just a sunfish hull, but switching to a higher-aspect sail.
 
I have two zip-ties on my upper spar: one to mark attachment for racing, and one for casual sailing or carrying a passenger.
Why?

Passengers generally don't like to have to scrape under a sail on tacking/jibing, and they especially don't like getting whacked. Plus you can see better.
So you'll get more repeat customers. Its just good for business.
 

beldar boathead

Well-Known Member
I have two zip-ties on my upper spar: one to mark attachment for racing, and one for casual sailing or carrying a passenger.
Why?

Passengers generally don't like to have to scrape under a sail on tacking/jibing, and they especially don't like getting whacked. Plus you can see better.
So you'll get more repeat customers. Its just good for business.
So true. Alan Glos mentioned this also, saying it "...reduces boom-on-head incidents..." !
 

Alan S. Glos

Well-Known Member
The higher rig (AKA: the "Geezer rig") is fine for non-racing, day sailing, but for speed and performance, lowering the boom is da bomb. I think it has a lot to do with the fore and aft balancing aspects of the rig - I just know it works.

Alan Glos
 

Weston

Active Member
A higher sail does not by itself generate more power. Only a bigger sail, or adjusting sail trim, can do that.
Thanks for the detailed and thoughtful response, Gregory. I definitely learned some points. thank you.

One follow up... Charles Howard's post (Message #5) refers me to the blog on tuning a Sunfish for racing by Eduardo. In that blog Eduardo says, "Lowering halyard location raises the height of the boom above the deck. This adds power to the sail." I'm trying to resolve the apparent conflict in the two statements.
 

Sailflow

Active Member
If you go to a regatta most boats have their halyards tied at 106" (from the bottom end cap). Eduardo mentions 106 and 107".
Gooseneck adjustments are 1 inch, all small changes.

If you are day sailing put your sail up so you are comfortable and get on the water.
 
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Dickhogg

Active Member
A thing I love about the sunfish is that you can change the boom height like this. I have never sailed anything else where you can.
 

norcalsail

Well-Known Member
Last July in Wisconsin, my neighbor had bought a Sunfish and we sailed together. He had his sail high and pulled forward at the gooseneck. I had mine rigged more according to Eduardo. I thought I would have no trouble being a lot faster than him. He has a lot of sailing experience and when I concentrated, I had an edge on him but I was too busy messing with my GoPro to make consistent gains on his boat. When the wind picked up, he was hiked way over and sat high up on the edge of the deck. I wished we could have sailed together more as I would like to have tested myself to a greater extent.
 
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