Downwind sailing, while glorious, requires careful attention to the boom. The dangers of accidental gybes to crew and equipment cannot be overstated. Boom preventers can be purchased – like this Winchard Gyb’Easy– or if you have sufficiently long line, you can rig one yourself.

As you consider the best choices for your sailboat, there are many resources and sailing coaches who can help you with your individual needs. Our two top considerations are rigging and crew preparation are the two key elements to keep in mind.

Rigging the Preventer: The most important consideration for where to attach the preventer is whether your attachment point damage the tube. We recommend looking for an attachment point at the end of the boom and leading the line as far forward as possible before returning to the cockpit for maximum resistance and control – so keep that in mind when selecting a line with sufficient length to accomplish this task.

Once rigged, the preventer essentially becomes part of your running rigging – slowing the swing distance permitted by the mainsheet. It must be accessible from the cockpit and easy to use so that you may gybe and/or adjust the sail while underway. Ensuring safe control within the cockpit will increase crew safety by allowing you to avoid unnecessary crew movements outside the cockpit.

We found the diagrams drawn by The Rigging Company in Annapolis, MD useful and easy to understand.

Practicing with your Crew: Practicing planned and accidental gybes with your crew is the next step. An intentional – or planned – gybe requires simultaneous easing and pulling in of the mainsheet and preventer as the boom swings across the stern. Crew members who must go forward should work from the leeward side of the boom in case of an accidental gybe and the helm must keep a careful eye on the crew.

Accidental gybes, especially at night, can be alarming, noisy, and dangerous. Boom preventers can reduce this danger. Maintaining helm control to return the boat to a comfortable degree of heel as the boat returns to the original gybe will be easier with advanced practice.

For an interesting discussion and a handy video on installing and testing a book preventer – we recommend this article from Yachting World. And for a some fun viewing – these Accidental Gybe Videos are fun to view.

To discuss this or any other questions to help you advance your sailing skill, contact us at

Stay safe and have fun out there!

Tracy Sarich – Head Instructor (Canada), NW Yacht Group/Cooper Boating