Boom Brakes and Preventers

When sailing down wind we eventually may find ourselves having to perform the dreaded gybe.  Depending on conditions and wind strengths, this can be relatively painless or really scary. A violent gybe, which causes the boom to crash from one side of the boat to the other, can cause major damage. In some instances the boom and its attachments can break or bend, the mast can break or bend, and/or the standing rigging can be shock-loaded causing premature fatigue or even failure.

For an intended gybe, control the mainsheet and boom using the boat’s established procedure and keep people clear of the boom and loaded tackle. Do not grab the mainsheet tackle or use your hands as a friction brake. Practise controlled gybes in suitable conditions with qualified instruction.

To help make things easier let’s talk about what are some good hardware/ rigging solutions:

A boom brake can help slow the boom during a gybe, but does not eliminate the need for careful steering, sail handling and a correctly designed installation. It is exactly as it sounds, a device that provides a braking-action by applying friction to a line that is rigged athwartships. There are several manufacturers of boom brakes worth checking out: Walder, Dutchman, and Wichard, just to mention a few. The only downside I see with these systems is that the line that has to be rigged athwartships and if you are not careful, can trip you up on your way forward. There can be several ways to rig your boom brake so make sure you ask your local rigger what set-up suits your boat optimally.

The boom preventer is a more traditional, highly effective method that can, if rigged properly, leave your deck clutter free. The preventer, unlike the boom brake, is to be rigged to the very outboard end of the boom via a pad eye and pendant (see diagram). Many people come up with their own inventions but do not realize that taking shortcuts can lead to boom failure. Here are some tips to rigging your boom preventer properly:

• always use an outboard attachment point
• the attachment point should be a heavy duty pad eye that is through bolted and not just drilled and tapped
• the boom should have a high-strength pendant spanning the length of the boom so that you can access the inboard-end easily when the mainsail is eased all the way out
• the inboard end of the pendant needs to have an eye to accept the shackle of the preventer control line
• the preventer control line should be stowed at the shrouds, go forward to a turning block on the bow and lead aft via lead blocks back to the cockpit, thus keeping the deck clutter free
• the control line should be long enough so that when it needs to be released (in a jam) it can allow the boom to gybe across to the other side in a controlled fashion
• the cleating mechanism for the preventer control line should be one that can be easily released in case of emergencies!

Choose the preventer line, attachment points and hardware for the boat’s loads and geometry. For a boom brake, use the exact rope and routing specified by its manufacturer; friction performance depends on them. For example, Wichard specifies its Gyb Flex rope for the Gyb’Easy. Neither system is a set-and-forget substitute for managing the boat. Plan how to release the system under load and monitor it as conditions change.

Remember you can always leave a comment if you have a question or a thought. Thanks for the read and we’ll talk to you again tomorrow…

Shop Dutchman boom brakes, Walder boom brakes, Wichard Gyb’easy boom brakes. Check boat, boom and line specifications for each system.