That is called a boom VANG. It is used to control the vertical angle of the boom while you use your mainsheet to control the horizontal angle. On boats without a vang...the mainsheet does double duty and is less effective at controlling sail twist and loss of power.
01-12-2008 06:21 AM
thanks for the reply i think i used the wrong term. i know what the boom preventer is the part that i was talking about is the part that is part way up the boom and goes to the base of the mast. it keeps the sail flat. how does this work with the traveler
01-11-2008 05:13 PM
Kenny...welcome! A preventer is generally used on a broad or beam reach when the winds are light and flukey and when there is some danger that the boom could gybe and swing rapidly over to the other side of the boat...beheading people and causing gear damage. Since this can really happen any time the helmsman fails to pay attention to his course or the wind on any tack...many cruisers will use one full time. In it's simplest form, a prventer is simply a line with one end tied aroung the boom and another end tied to the rail closest to the boom. This rope prevents the boom from moving back across the boat. More commonly, preventers are rigged with multipart tackle and shackles for easy adjustment and use.
There are more complex but better ways to rig a preventer and there are other products that work like a preventer but require little attention and lots more $$.
I am not very good at drawing so I will leave it at that for now! Perhaps some others ave a good illustration. I particularly like the preventers that are rigged from the boom to a sheave on the bow of the boat and then run back to the cockpit winch for easy and quick adjustment.
01-11-2008 03:28 PM
learning to sail
i have a 33 0/I. i have sailed on a corbin 39 and a 33 0/I before but neither had a boom preventer. just a traveler any one tell me how to use it and when to use it.