Most homeowners keep Band-Aids in their bathroom cabinets for minor scrapes and bruises while most car owners keep jumper cables in their trunks in the event of a dead car battery. Neither item is a basic need for everyday survival like food and water, but they will inevitably come in handy and can even stop the bleeding (literally in the one case) in certain situations.
Preventers function in a similar fashion: although they are not required for everyday survival, a preventer is a no-brainer if you own a large yacht of any kind. Preventers are crucial for downwind sailing because they will prevent (I love when words and their definitions are one and the same) an uncontrolled jibe / gybe. At any moment, the wind can change direction or pick up speed and before you know it, the boom comes flying across the boat. I have not forgotten about my novice readers so to answer your question, a jibe / gybe is a sailing maneuver whereby a sailing vessel headed downwind turns its stern (the end opposite the pointy one) through the wind, so that the wind direction changes from one side of the boat to the other.
Although you can rig lines and blocks into a preventer, a boom brake is definitely the way to go because once installed, it can remain indefinitely. I do not know about your crew, but mine likes to relax, soak up some rays, and crack open a cold brew or two. The last thing they feel like doing is jumping into action whenever we turn downwind or redo a preventer prior to a controlled jibe / gybe. For obvious reasons this would kill the calm, tropical vibe of the ride.
There are three different kinds of boom brakes available today for your sailing vessel: adjustable sheave brakes, friction brakes, and drum brakes. With the adjustable sheave method, a line weaves between three wheels. A knob is used to tighten and loosen the rotating bottom, or third, wheel. In this way, tension can be adjusted to act either as a preventer or to allow the boom to move freely if sailing upwind. It seems like even in the boating world the “third wheel” often gets the shaft (sometimes I just can’t stop myself from cracking a corny joke).
Often the simplest kind to install and the least expensive, the friction brake is next on the list. A line runs through the brake and increased tension on this line causes an increase of friction on the brake; there are no moving parts. While you can’t control the line-release speed, this is often referred to as the set-it-and-forget-it brake. If you are like me and even the task of remembering to set your work alarm via Amazon Echo each night is a chore, then this is probably the right choice.
And last but certainly not least is the drum brake where a line is wrapped around a drum that is housed inside of the brake and more tension in the line leads to greater friction. By wrapping the line around the drum once, twice, or three times, the friction becomes adjustable. Is it just me though or does this sound like a tedious project that would have to be done mid-sail and, therefore, negates the deftness of the boom brake altogether?
I went with a friction boom brake (pictures above) so I could set it and forget it. Which brake do you prefer? Comment below.