Pro sailors joining a new class expect to learn the boat quickly. They use their fundamental knowledge to dive into all the details of making the boat go fast. This post shows some examples of how you can accelerate your improvement.
Allan Terhune, Jr. of North Sails is relatively new to the MC Scow class. With the help of Eric Doyle, a North Sails designer, he spent three days learning the boat before the 2021 MC Scow Train Wreck regatta at Lake Eustis Sailing Club. They conducted an online post-regatta debrief open to all sailors.
View the recorded debrief below. We’ve summarized the highlights and provided the video timings. Pay attention to the individual points, but also reflect on their thought process. Perhaps the combination of fundamental insights and the thought process will help accelerate your improvement.
Video Highlights
Rig Tuning (3:30)
You can accelerate your improvement by experimenting with rig tuning, using two-boat testing and your sense of feel to discover what’s fast. Then take measurements to ensure repeatability.
- Mast rake (3:30). Suspicious of the repeatability of tip to transom measurements, they used an “arc” measurement on the forestay. This technique comes from other classes.
- Shroud tension (4:40). Suspicious of the repeatability of the “hand tight” setting, they used a Loos gauge, even though the MC rig is loose and not normally measured with a tension gauge. They tightened the rig so that it would register on the Loos gauge. Then they backed off a specified number of turns to find the settings that felt fast in light, medium, and heavy air.
- Spreader sweep (6:45). Spreader sweep regulates mast bend. After experimenting, they determined that 4″ of sweep with the standard 17″ spreader length was a good starting point. This number will be different for different sails and crew weights.
- Board height (9:30). Allan noticed that the boat performed better on one tack than the other. (The pros are very good at sensing how the boat is performing; you can accelerate your improvement by cultivating this sense of feel.) They measured the board angles on each side and found they were not symmetrical. To correct this they made marks on the board well to ensure repeatability.
Technique (10:45)
- Light air (10:45). Doing side-by-side testing showed the importance of getting the boat locked in quickly. See our post on Pro Tips for more. Allan and Eric also experimented with sitting forward to keep the bow attached to the water. Sitting forward is good, but too far forward gave the boat too much weather helm.
- Heavy air (15:00). Again, they did a lot of experimenting in side-by-side and using feel. Some key learnings:
- Boom needs to be outside of corner of boat when overpowered
- Boards need to be up 1-2″ or more to unload helm and prevent from tripping over the boards in a gust.
- Lock the tiller and keep the boat on its lines by working the mainsheet and the controls. “Let the boat do the work.”
- Look for overbend wrinkles to tell when you have flattened the sail as much as the shape will allow. You can have too much vang, indicated by when the lower batten hinges out. This unnecessarily reduces pointing.
- Transitions (22:50). Allan describes his challenges in learning to keep his head out of the boat to make better transitions in sail trim as the wind changes and to see where to go on the course.
- Cunningham (29:20). They discovered that the cunningham is super important in big breeze, since a large portion of the top of the mast is unsupported. Without upper stays, only the cunningham and mainsheet are available to control the top of the mast. Big breeze requires huge cunningham tension.
New Sails from North (32:25)
North is now offering two sails for MC Scow – the Rocket, which is a flatter cut sail and the Magnum, which is fuller. Magnum: A fuller cut sail. See the video for more details.
Recap: How to Accelerate Your Improvement
We took away four key points about Allan and Eric’s thought process:
- Dig into the details. Sailing is a game of inches. The more details you can perfect, the better.
- Experiment. You know the old saying about doing the same thing and expecting different results …
- Measure and repeat. Take notes, mark your settings.
- Increase your fundamental knowledge. Learn why the rig tuning settings matter. Figure out why different techniques work in different conditions.
Light Air Boat Speed – Focus on Flow
SailZing series on Shaping Your Mainsail
