a sail is kinda like the wing on a plane the curvature creates faster airflow across the front side of the sail this creates lift or in this case it's called drive, when the sail is flattens out it removes some of the drive as for the inside it's like cupping you hand out the window of your car it will catch more air while cupped then when flat. but you are also correct that if there is too much curve in the sail you will also loose drive this is when the sail stalls it is like a wing pointed to high it will loose all its lift, I just did not want to get too specific in my last post I guess that would be my bad! I hope this explanation works and you get in some good sailing Mike M
From: [EMAIL PROTECTED]: [EMAIL PROTECTED]: RE: catalina27-talk: Boom vangDate: Fri, 22 Jun 2007 06:29:33 -0400 Wait, this sounds backwards … without a vang (and the traveler in center position), as the wind increases the sail has more twist in the upper portion. This causes the wind to spill and reduces the main’s power. In an extreme case you can see the upper portion of the main luffing. By adding pressure on the vang, you pull down on the boom which brings the upper portions of the main parallel to the boom, this reduces the twist and increases the power in the upper portion of the main. Joe McCary Aeolus IIWest River, MD [EMAIL PROTECTED] On Behalf Of michael mcvey tightening the vang flattens the sail witch spills wind this take pressure off of the boom and mast as it removes drive from the sail. we used our vangs allot racing lido's I hope this explanation helps. e Search Club. Join Live Search Club! _________________________________________________________________ Make every IM count. Download Windows Live Messenger and join the i’m Initiative now. It’s free. http://im.live.com/messenger/im/home/?source=TAGWL_June07
