Daysailer boom vang led to centerboard trunk

Moderator: GreenLake

Re: Daysailer boom vang led to centerboard trunk

Postby GreenLake » Wed Jun 13, 2018 8:14 pm

"Ease-hike-trim" is like the standard response to a gust when you are sailing upwind.

Easing reduces the heeling moment a bit, but also, when a gust hits, the apparent wind shifts aft a bit.

gust.jpg
Wind angles in a gust
gust.jpg (24.54 KiB) Viewed 871 times


(Red/pink is the condition before the gust)

Therefore, letting out the main also improves the trim and the gust can be translated into more speed.

As the boat accelerates, the apparent wind shifts forward again and the main can be trimmed in.

This assumes that the gust only brings a change in wind speed. Often the gust will also create a change in direction as gusts are in many cases faster winds from above that come to the waters surface as part of turbulent motion in the air mass. (At other times, gusts can be vertical, falling wind that spreads out when it its the waters surface).

Winds that are not at the level of the water can be blowing in a different direction (wind shear) and that brings a change in wind direction during the gust; that direction is independent of the shift of apparent wind and can go in either direction.
~ green ~ lake ~ ~
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Re: Daysailer boom vang led to centerboard trunk

Postby DigitalMechanic » Thu Jun 14, 2018 8:15 am

Easy-Hike-Trim...

Often you are already hiking. I keep telling myself I am going to put hiking straps in the boat. After being on other boats (on the Thistle it is pretty much a requirement), I have realized the value of being able to dip back. There are times when the trim on all your sails is being reported as ideal by the tell tails, however you still seem to be over powered because you are healing to much. Your option is to either ease the sheet or hike harder (dip, or lean back until your back is parallel with the water or perpendicular to the mast... however you want to look at it). If you (and the crew) do this a few times, a lot of times you can nudge the boat back upright so you don't have to ease the sheet.

Ease-hike-trim is the golden standard though, as it allows you to de-power, flatten the boat, and then power back up. Like a down shift, gain control, and then shift gears again.

I have been working tirelessly on this Catalina 22 for the last 8 months, and now somehow a Hobie 18 has been dropped in my lap that I have to find a home for, lol. But beer can races are starting up at the Rudder Club, and I am going to concentrate on making the Daysailer competitive... A hiking strap project is in the very near future, lol. Cheers!
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Re: Daysailer boom vang led to centerboard trunk

Postby GreenLake » Thu Jun 14, 2018 10:01 pm

At our beer can races the winds have a habit of dying right around the start signal for the dinghies :twisted:

Anyway, as a result, we don't often get those conditions where the last little bit of hiking out makes a difference. Sitting on the rail and leaning out without assist usually does the trick. As a result, I may now have a habit of depowering a bit early, on the few days the wind does pipe up. In essence, I'm not fully in race mode.

Keeping my sails flat helps a lot in reducing heeling moment: rig tension, outhaul tension and vang tension (plus some cunningham).

Which leads us back to the vang, which started this discussion.
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