A-Syms Dead Downwind?

Christian Williams

E381 - Los Angeles
Moderator
Blogs Author
I don't know how many Ericsons tack downwind, which is where an inventory of asymetrical spinnakers earns its keep.

But apparently some fast boats are finding now that they can sail an asym dead downwind, on a pole, for superior results. Many of these boats abandoned traditional spinnakers years ago, since DDW was considered slow.

Must depend on the boat. But does seem to apply to the value of keeping a spinnaker pole on board even today.

 

Loren Beach

O34 - Portland, OR
Senior Moderator
Blogs Author
Ah So. Same UKSails message just hit my mailbox. The explanation makes sense to me, FWIW.
 

Geoff W.

Makes Up For It With Enthusiasm
Blogs Author
The Schock 35 I do "serious" races on poles out their assyms. We can sail pretty deep, if not straight DDW. going wing-on-spin helps get a few more degrees as well, but talk about a sensitive point of sail.
 

debonAir

Member III
When it is windy enough to hit hull speed it makes sense to go as deep as possible if that's the way you're going. One asym trick is to wing-on-wing but also sheet in the main half way to channel air into the spin a bit sideways to keep it "pushed out" without a pole. Good point about keeping a pole handy though but of course then you're keeping all the other parts of using a pole handy as well so might as well use a real chute to go dead down at that point?
 

Keith Parcells

Sustaining Member
You’ve got to have a very full cut asym to even get close, I think. My gennaker most definitely could not. But bear off a bit and go real fast, and then gybe, and do it again. :p
 

markvone

Sustaining Member
There are two concepts mentioned in this thread: poling out an asymmetric TACKED to the pole (like a symmetric) and wing and wing with the pole on the clew (like a jib). Some boats have an articulated sprit that allows some projecting of the chute to windward.

The advantage of an asymmetric chute is that it can be optimized aerodynamically for air flow one way (leech to luff). Put it on a pole to project to windward, design it full with big shoulders and it can run DDW BETTER than a symmetric. The downside is you have all the complexities of a symmetric, jibing the pole, different size chutes and cuts for running and reaching. So PHRF will adjust your rating if you go full-monty assym on a pole even if the size is per the standards.

When you pole out a jib or a-sail via the clew (wing and wing) you get sail projection but the air flow is actually reverse (luff to leach) of how the sail is designed.

Mark
 

Brad Johnson

Member II
I have an Asymmetric on a sprit and have not used it wing on wing but I saw a pro crew using that technique at Block Island race week last year and in light to moderate conditions (10-15 Knots) it looked effective. IMO a asymmetrical is to big for a pole , It would be tough to depower, I spent a lot of $$ and time getting rid of a Spin pole and have no intension to resume that practice
 

e38 owner

Member III
I have a runner asym racing chute. This is what I have found.
The fastest depends on wind speed just like a sym
If it’s blowing hard and you want to Ddw a sym is slightly faster. Can sail deeper but it is a little more hairy

With pole about 30 degrees can sail about 140 apparient in moderate wind
Can sail between 120 and 90 apparent in lighter winds and make up for extra distance. Need to just keep testing. Easy to get low and slow or to high and sail to far. Get speed as apparent wind moves forward sail low. If done right can find a sweet spot. If not to high too far or too low too slow

In smooth water like with a sym sailing by the lee can be fast. Sym pole way back. Asym wing on wing
 

kiwisailor

Member III
Blogs Author
Spinnaker what's that? My boat still carries her spinnaker pole on the deck as it saves my toes from being stubbed on the deck chocks if I removed it. But I did use the pole once to pole out the old 150 genoa and run wing-on-wing with the main out on the opposite side in light air. It worked surprisingly well. Not sure if it would work well with my new high clew 135 genoa.

For those of us with non furling mainsails there are times when jib alone is more than enough. Also far easier to reef while underway, reefing the main while underway scares the admiral :)
 
Top