Listen to your HELM!
Skip Dieball
For many years, I have been giving clinics and helping folks try to get more out of their Thistle sailing experience. We do this sailing thing for fun and the easier it is to sail your Thistle, the more enjoyment you’ll receive.
One particular facet of sailing Thistles that is tough to master is managing the helm. Too often I’ll see a team that has excessive helm (myself included!), that is when the driver is driving/working against the boat’s natural course. I attribute this, partly, to the Thistle being relatively light-helmed. There are plenty of boats out there that have a heavy helm, so when you come to a Thistle, the relative tug on the tiller is so much less that many don’t recognize what the boat is communicating.
Weather helm is what we generally experience when going upwind. Here’s a picture of my team from the 2009 Thistle Great Lakes (photo by Charles Scott). Look closely at how far off centerline my tiller is. Granted, I could give you the exact scenario and justify this, but the point here is that I am fighting the boat and therefore not going as fast as I can.
What contributes to excessive helm? There are generally three main factors: 1) Sail Trim, 2) Boat Balance/Heel, 3) Position of CB. For the Thistle we can zero in on each factor and try continue to use points of reference to reduce the amount of helm the boat has, and thus go faster in a straight line (and arguably higher with added hydrodynamic lift).
Sail Trim. Generally speaking if you understand the concept of how the sails affect the way the boat goes through the water, you are already ahead of the game. For many, we do understand, but we don’t always use the sails to help us listen to the boat. In its basic form, the jib pulls the bow down away from the wind and the mainsail, when trimmed, lifts the bow up to the wind. On a perfectly balanced boat, you will be able to feel any change in helm by just a click or two of trim on either the main or jib. Because the Thistle is so “mainsail driven”, we need to focus more on the mainsail as it contributes to the helm. Constant adjustment will directly affect the helm of the boat. That is why many people have taken off their mainsheet cleats, to force yourself to hold onto the mainsail and adjust the main as it relates to the tug of the helm. I have a mainsheet clean and always will…just my style. But for those that have sailed any of my boats, you’ll know that the cleat is set low enough that you have to work hard to place the mainsheet in the cleat, and conversely it is easy to uncleat…this is the same as not having a cleat, though my hands are grateful that I do!
So when you are on your close hauled course with the jib trimmed just inside the rail & about 1-1.5” off the spreader, you are now working the mainsail as an extension of the helm. Trim the main harder and the helm will increase. Ease out and the helm goes more neutral. Find this range, mark your mainsheet, look at the spread between the pulleys @ the transom…do anything you can to gain better understanding of the range and create a point of reference that you can then quickly check when the boat seems slow. Take this knowledge and then plug in the depowering factors (vang sheeting &/or traveler adjustment) to fine tune the balance through main trim!
Boat Heel/Balance. The Thistle is a dinghy. Moreso than many other smaller one design boats. For this reason you have to have good communication with your team about your fore/aft weight placement and, as it relates to the helm, the side to side balance. When I was a Jr. Sailor my coaches always preached sailing the boat flat and that the rudder was a brake if you didn’t. Not for a number of years after did I “get” the concept. If you think about the amount of heel you are carrying upwind and then correlate that to the tug on the helm, you’ll quickly understand this concept. The question always asked is “how flat do I need to sail”? The answer, as we have witnessed in GPS tracks of sail testing and boathandling, is that the flatter the faster. I like to challenge Thistle Sailors to find the transition point of helm (the point where the helm goes from windward to leeward). That is as flat as you’ll want to sail. In some cases (especially lighter winds), you’ll want and need a little windward helm to gain hydrodynamic lift off the blades. When you gain a slight increase of helm, you should work on managing that with sailing flat and regaining neutral helm. This is an important range of balance that you need to work with your crew to perfect. It all translates into faster sailing!
Position of Centerboard. Fortunately for us in the Thistle Class, the Centerboard down position is pretty standard. Only in a few cases (namely older boats) will you recognize reduction in helm by rolling the CB back in the trunk. The theory is that you bring the Center of Resistance more in line with the Center of Effort. On my woodie, #1234, we have the ability to move the board aft and reduce some of the helm, though I would argue that we could achieve the same “feel” in helm by depowering the mainsail or hiking harder/balance. The point here is that there are a number of One Design boats out there that have CB’s that are integral to the balance of the helm. Be sure to read the tuning guides and ask the experts if you have a question as to whether you could reduce the helm by moving the centerboard. In the Thistle Class you’ll find that some folks do and some don’t. That is why we practice and experiment at the club races!
In conclusion, the purpose of this article was to get you to think about helm. As I already mentioned, too often I’ll see a boat sailing upwind with too much helm. By easing the main (or depowering), balancing the boat or goofing around with the CB position, you will find the boat’s sweet spot and recognize better upwind performance.