working the boom vang

Submitted by frank barbehenn on Sun, 07/08/2007 - 09:57
I understand that you use the boom vang in winds about 13-15 knots and above to flatten the sail to lower the drag by decreasing the depth of the sail. But I read that in winds of 17-18 and beyond that some have a differing approach: they recommend loosening the vang in order to loosen the leech, allowing it to twist and spill air at the top. Doing so, they say, takes the pressure off the top of the sail, decreasing the heeling moment, thereby making it sail flatter. This loss of power doesn't affect boat speed they say because the winds are already high and the boat already maxed out in speed, and the absolute goal is keeping it flat. Thus spill the air. Any thoughts out there re this?
‹ Keeping the Scot flat with a light crew CMR 81 ›

Comments

Well, firstly, I think that when you begin to apply vang has les

Submitted by Tripp on Sun, 07/08/2007 - 10:35.
Well, firstly, I think that when you begin to apply vang has less to do with an absolute wind range and more to do with how overpowered you are. Lighter crews will bring it on sooner than heavier. The goal is to keep the boat flat, flat, flat. So do what you have to (and when)to make it happen. As for letting it off in really high winds, I haven't heard of that being done. In those winds you're essentially vang sheeting and using the mainsheet like a traveller to dump air. In my mind, when you dump the sheet, if the vang is loose you just make the sail fuller and less stable. Everyone has their own techniques, but that's probably not something I'd really do. Also, it's important to remember the cunningham when applying vang. While the vang flattens the sail, the cunno will bring the draft forward and help keep a more effecient shape. The two should work in tandem. [8] FS4830

The advise to ease the vang to spill air in heavy breeze while s

Submitted by Jay Lott on Tue, 09/11/2007 - 16:20.
The advise to ease the vang to spill air in heavy breeze while sailing upwind is obsolete for the most part. Also, it applies to boats other than Scots. In the Scot it is essential to keep a tight vang upwind in heavy air because the vang tensions the forestay. This is not true in most other boats. A loose vang (sagging forestay) in a Scot will power up the jib, put hook in the leech of the jib when you don't want hook there, and destroy your ability to point. Bend that boom with the vang upwind in a Scot! J. Lott