Sailing downwind!

sailingmania

sailingmania

New Member
Hi i recently heard that sailing a laser down wind you need the outhaul fully on tight to increase sail area? is this right as i have always let the clew slack to give the sail more baggyness? if so that would make the laser classic pull everthing on tight and leave it better at sailing downwind as they do not adjust their outhaul would this be right? please could someone tell me whats right!

cheers
Jack
 
sailingmania said:
Hi i recently heard that sailing a laser down wind you need the outhaul fully on tight to increase sail area? is this right as i have always let the clew slack to give the sail more baggyness? if so that would make the laser classic pull everthing on tight and leave it better at sailing downwind as they do not adjust their outhaul would this be right? please could someone tell me whats right!

cheers
Jack
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That is false.

I could be wrong, but I believe this is one of those really old theories.

You want to loosen your outhaul down wind, but not excessively, of course.
 
Very false. Think about it. When you're going downwind, You want to create a pocket for the air to come in, and stay in. When you have the ouhaul pulled all the way in, the airs just flowing off the side. This is the reason you should let off everything DW, and tighten everything up in heavy air.
 
>>Hi i recently heard that sailing a laser down wind you need the outhaul fully on tight to increase sail area?
This is true. The projected area is bigger. But the question is: is this fast ? And the answer is no. Fast downwind never is dead downwind. You have to put some air flow over the sail to produce some lift on leeward. To produce lift you need some bag in the sail and the correct angle of incidence, even by going higher or by-the-lee.

>>When you're going downwind, You want to create a pocket for the air to come in, and stay in.
Beg your pardon, but this sounds like "a sail is a wing and there is a stream between main and head sail" summer sailing school explanation.
Sails are much more diferent from wings, planes and bags. (be sure, i also didn't understand all sail theory ...)

HTH, Peter.
 
Depends on what angle of down wind sailing we are talking here....

For dead down wind (i.e. on a run) you will get a splitopinion. You will get the 'projected area' crowd who say you need the sail to 'belly out' (ie.e Outhaul off) and you will get the other crowd who say you want the maximum area facing the wind (outhaul on).

My personal opinion is that if you are seing a big change in this then you must be an olympic level sailor. I would conecntrate on boat trim an abalnce as these are far more likely to affect your boatspeed going dead down wind.

For any angle where you get flow over the sail you should be setting the outhaul in the appropriate manner for the winf strength.

I tend to leave mine alone whilst racing but the club I sail at is on a small lake so the small differences you will see are lost because boat handling, trim and balance are far more important.

My advice to you would be listen to what the top guys at your club do and then watch them to see if the actually do it when racing ;).
 
I'd say partway....dead downwind you aren't adding much in the way of sail area just by bagging the sail. And most of the time, we rarely go perfectly DDW; it's always variations where you might want a bit of flatness.
 
I recommend never sailing DDW. Sailing by the lee or on a reach is much faster, and much more stable if the wind picks up. In both of these cases, I need flow over my sail so i never let it BAG. However, if you have horizontal creases along the foot of your sail, then thats slow as well.
 
I might ease it out a coupld of inches depending on what the breeze is doing. If it's light I'm sailing with close to a max loose outhaul anyway, so I just leave it. If it is really blowing I'll ease it off the max tight setting from going up wind and if it is blowing medium I'll either ease it an inch or 2 or just leave it.

Either way I never sail DW with a "tight" foot on the sail.
 
bear in mind when you ease vang and cunningham for the downwind leg some fullness will return to the foot of the sail - this is why in the old days very few sailors would adjust the outhaul downwind unless the leg was long and the 2-3 percent possible benefits were posible and worth the time to achieve.

Since then the new adjustments make it easier to adjust the outhaul. Also more people are sailing with the rig unstalled by the lee.

If the sail is stalled (i.e. constantly dead downwind) there is an argument for maximum projected area but not if the foot tension compromises rig flex to sync with wave action.

once by the lee or on a broad reach when the sail is unstalled you should be guided by flow and rig yielding considerations. Because of current S curving techniques downwind you will probably be seeking to sail unstalled for more than 90 percent of the time so flow and rig dynamics in waves or gusts will be the determinant factors. Some differences in degree of trin seem apparent in the radial (very sensitive to outhaul tension) compared to the standard and 4.7 cross-cuts.
 
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