What is a Boom Vang?

BoomVang

A boom Vang is a rig set up on a sailboat that helps keep the boom on the boat from raising up.

A simple boom vang is a simple block setup on one line that gives you a mechanical advantage that lets it hold the boom down when it is out over the water on the side of the boat. 

A boom vang is usualy attached about 1/3 of the way aft of the mast. A  bail or a "U" shaped bracket  or eye attaches to the underside of the boom and another bail or eye at the mast base are where the boom vang is attached. The vang consists of a three to four part block and tackle on a line, or on larger sailboats it may be a rigid hydraulic tube.

 
 












The lower block attachment should have a quick-release set up like a cam action cleat. You need to be able to release the vang quickly to prevent boom damage in case the boom dips into the water.