Tuesday, June 2, 2015

Cheating the System

Often, you may notice while sailing that your top third of your headsail luffs when reaching, no matter how much tension you place on your sheet or where you position it on the track. When close hauled, a non-overlapping is rigged normally using jib sheets attached to the primary clew, and then led through a sheet block attached to a short genoa track, then back to the cockpit.  But this setup has a limitation.  When the boat bears off onto a reach, you typically let the headsail out.  This induces a loss in power as leech twist forces the top 3rd of the sail to open up, decreasing flow, and rendering this part of the headsail luffing and useless. 

Recently, we solved this weakness by adding a second clew, located higher on the leech.  Raising the point of attachment means the sheet is pulling more “down” on the leech.  This replicates the concept of moving the genoa car forward.  The setup involves positioning the secondary clew (in this case, a 2-inch Vectran loop) about 24-inches above the original clew higher along the leech of the sail.  With the original clew still connected by the primary sheet, the fixed line will help extend the leech of the sail to reduce twist, re-engage the top third of the sail, and generate more power while sailing through 60 to 90 degrees of apparent wind.

Like a barber-hauler that pulls the sail out, or a long genoa track that allows you to move the car forward, this is a way to get the most power out of your sail and extend its life.  For self-tacking jibs on tracks in front of the mast, boats (mono or multi) with very short genoa tracks, or for a smaller sail that already sheets to the front of the track you have, this addition can help you enjoy your headsail more and get the most out of it.

Written by Owen Kaufman, Super Sailmakers

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