I'm settling on parameters for having a trysail built. I am trying to follow the conservation here to make sure I get this right. The sail's foot is to be a foot shorter than the boom, allowing the clew to be hauled out to the boom end, which I envision being lashed to the gallows in the center notch (with the mainsheet hauled in tight to hold her down)...... Am I getting this about right? Thanks for any comments...
Iíd recommend you forget about setting the trysíl to a boom thatís lashed in the gallows. What happens if the boat swings so that the wind is abeam? Sort of like what happens with a mainsíl sheeted in hard and the helmsman falls off the wind without releasing the mainsheet. In a strong wind it can result in a knock down.
You need control over the sail if you want to keep the boatís helm balanced and make the boat go where you want it to go. Most auto pilots donít do very well in a storm and you will need to get the helm balanced so you donít wear out the helmsmen prematurely. Even when you heave-to you may find that the set of the sail needs to be adjusted to get the boat balanced properly.
Think of the trysíl as a really small main sail -- use it like you would a main.
Also, if youíre going to set the trysíl on the boom remember that you will loose the ability to lower the CE of the sail. When a trys'l is set loose footed on itís own track you can position the tack as high or low on the mast as you want. This lets you play with the center of effort (CE) of the sail. When the wind gets up you want the CE of the sails low. Thereís a brief discussion of all this at Mariner's Web Ľ Blog Archive Ľ A Strategic ďSail PlanĒ