Strategery with Dave
“Don’t Be a Slave to the Tuning Guide!”
David Sample
Dave’s Note to Readers: This article is mainly meant to apply to keelboats, but even if your boat is a center-boarder or cat and doesn't have a backstay, the same principals apply – however, they must beapplied slightly differently. Cats have a powerful downhaul and mainsheet, both of which bend the mast, and on both types of craft the mainsheet tension also controls the amount of forestay sag if you don't have your rig too tight to begin with!! So, read on and heed.
This article initially appeared as my reply to a post on the S7.9 website. Here’s the post: “Upwind you need to adjust the backstay tension according to forestay sag but the best advice is to consult your sailmaker. We sail with the backstay completely off downwind in all wind strengths with great results."
Here’s my reply: I agree with this with a couple of caveats. I'm one of those who is always testing the rig and sails to see if the boat/wind/sea conditions can/will handle a higher gear [flatter sails]. Some long-time, very famous, sailors like Dr. Stuart Walker say just the opposite. Apparently, he and others who think this way never sailed cats much! When ANY boat gets close to the maximum lift:drag ratio for it's current sail setting and wind and sea conditions, it's the same thing as winding an engine out in a certain gear. There comes a point where the only way to go any faster is to shift to a higher gear. In a sailboat, that means going to flatter sail shapes. This doesn't make sense to some folks but Randy Smyth explained it very well back in the 80's: "When you have more lift than you can use, the only way to go any faster is to minimize drag". Randy was speaking mainly of trapezing conditions and up but this concept applies across the board. You’ll never realize its truth and the resulting benefits to upwind speed unless you’re willing to buck the tuning guide from time to time! Remember, ‘There ain't no free lunch’ - anytime you increase lift you also increase drag and vice-verse. Full sails make lots of lift but at the expense of lots of drag!!
On any boat I sail, I set the rig up for the LIGHTEST expected conditions because without the needed ‘low gears’, accelerating away from the start, out of tacks and through boat wakes/bad waves is a losing proposition. Now, that frequently means my rig is looser than anyone else’s, and looser than the guide says. Depending on the sailmaker, some tuning guides/classes say to NEVER touch the backstay until a certain wind speed is reached. This is CRAZY!! You’ll never learn if your boat is capable of going any faster in ANY conditions unless you semi-continually experiment with the flattening controls, and on a boat with a backstay adjuster, that is control numero uno!
I'm not suggesting anyone ignore their tuning guide, just remember and take to heart the title: It's a GUIDE, not a set-in-stone book of rules that MUST be adhered to or else!
One last thing before anyone jumps on the "I'm not in a cat" bandwagon. Cats keep going faster to a point as long as they have enough righting arm [weight on the traps, racks, whatever]. Most keelboats are limited by hull speed, and most smaller keelboats won't do hull speed upwind. Guess why: Too much DRAG on the rig/sails for the total driving force that can be generated! But, and this is a big but, wouldn't you rather reach the maximum speed for "X" conditions FOR YOUR BOAT sooner than those around you AND be able to achieve a HIGHER maximum speed than those around you, even if it's only 10ths or 100ths of a knot more?