Re: genoa for 30T Hunter
Sadly, there is no one right answer. The best headsail size depends on wind conditions, boat design, and your sailing skills. The general consensus here on Sailnet is that a 125% to 135% is the most versatile sail and will work in most weather conditions, and that's what I'd recommend for you.
The usual approach is to have multiple headsails, although with furling you don't need quite so many. If money were no object, I'd have three furling headsails -- 100%, 130%, and 150% jibs, or thereabouts. The most used one is the 130% genoa. The reason it does not handle all conditions is that you can only roll so much of it onto a furler without spoiling your sail shape and creating a big cylinder that spoils airflow over the leading edge. Once the airflow becomes turbulent you lose some power, even when the sail is trimmed properly.
I'll tell you about my experience. My boat is a masthead rig so most of the power comes from the headsail. It came with a single headsail -- a 155% genoa made with what feels like 8 oz dacron (big and heavy). I can roll out the headsail completely if the wind is less than 6 or 7 knots. Any more wind and I need to furl it some to eliminate weather helm. A large, heavy sail with such a large foot to luff ratio has another disadvantage: it is hard to achieve good sail shape on a broad reach or a run. This year, I bought a smaller head sail from Bacon's -- a 125% genoa -- and intend to use it as my primary head sail.
Based on my current experience, I'd set it up differently if I were to buy a new 150% genoa. Presuming I have smaller headsails to use normally, I would set it up more like a drifter. I'd specify 4 oz Dacron and use it with small, light sheets so it doesn't collapse so much in very light winds. If you decide to do the same, just know that material that light it is limited to winds below 8 to 10 knots.
T. P. Donnelly
S/V Tranquility Base
1984 Islander 30 Bahama
Last edited by dacap06; 03-18-2012 at 12:35 PM.