DN NA Class

Guests & Members Post & Read => Sailing and Tuning => Topic started by: DN 5449 on December 27, 2010, 05:48:59 AM

Title: Sail shape
Post by: DN 5449 on December 27, 2010, 05:48:59 AM
Sailing in about 8- 10 mph winds yesterday with smooth ice and about 1" of light snow cover,I noticed while going upwind my lower telltales where showing a stall while my upper ones where showing a little luff.At the time I felt like I was pretty much on the wind and played around with easing the sail and also trying to come up with unnoticable increase in speed.Also at the same time noticed the bottom of my sail (near the window) was luffing slightly,almost looked like the effect you get when sailing on a boat with a jib and the jib is back winding the main.This luff was only noticed at the lower 1/3 of the sail.I am sailing with a 2007 FO1 Boston sail,that still seems very crispy.I was also sailing with shrouds slightly looser,and mast a little straighter.
Normally if I read this on a sailboat with a traveller it would indicate to me to travell inward,not sure what the main is telling me here?

Title: Re: Sail shape
Post by: Ken Smith on December 27, 2010, 04:36:15 PM
Well, it might be telling you you need a flatter sail.  At least for max speed.  A fuller sail lets you accelerate from the start and out of tacks.  Its a trade-off.

Or it might be telling you to bend the mast more.

Or it might be telling you that the mast is over-rotating.  Move the boom or deck blocks to pull some of the rotation out of the mast when sheeted to be two-blocked.  Try alternate mast base location for pivot.

Or it might be telling you to move to Florida.  No one else seems to be able to be sailing....

Title: Re: Sail shape
Post by: Geoff Sobering on December 27, 2010, 04:50:26 PM
More outhaul tension to flatten the lower sail?