Centerboard

Then your study seems then to conclude that the daggerboard is more efficient than 'turbo' fins in getting the AI to point higher into the wind which is what I was wondering. I wonder if the difference is enough to want to carry the dagger-board? I mostly continue to peddle whilst sailing these days for a bit of fitness which itself improves the boat's pointing ability without the daggerboard as I tend to steer it closer to the wind.
What is the situation downwind Bob? Is the drag produced by the turbo fins in the up position whilst sailing off the wind stifling boat speed according to the gps?..Pirate

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Master of the galleon 'Pirates Lot'

I've done some experiments with boat speed with the drive in or out Pirate. If the drive is in, but you are not pedalling, it necessarily slows the boat. On the other hand, even leisurely pedalling results in higher boat speeds than having the drive out, at all points of sail. This applies in light to moderate winds. When the wind is fresh and the boat is really chugging along, pedalling seems to make only a slight difference. I'm with you - if the drive is in, you might as well pedal and get a bit of exercise.

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Yep, I always carry it, but I'm out in good wind during most of each outing. I agree with Chrisj's results.

Pirate, what wind speed are you sailing in? I often am breaking 10-12 knots (more trips than not), except for fishing trips. When the wind and waves come up, every piece of the AI is helpful in making it a safe, enjoyable trip. I think most of the (at lease my) comments are about light wind and little to no waves.

In 4-6' wind waves (or worse) I want my daggerboard down, and my fins in and ready no matter what direction I'm going. If the wind turns me suddenly, or I choose to turn quickly, everything better be set to do it's job. If the wind is gusty, I even keep the sheetline unlocked , in hand, and use my arm as a "shock absorber" to ever out the gusts.

Stop by some time and I'll take you out and show you

Downwind is very hard to measure. With light wind and waves you could take everything out and put in the plugs for the least drag, As I mention above, in good wind and waves, it doesn't matter, maybe even helps slow down a little to have time to turn at the bottom of the waves without submarineing!

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Hobie Island Sailing since 2006

Very interesting stuff guys and thanks for your informative inputs. My personal feelings remain unchanged and not being a purist I like simplicity and not having to carry a dagger-board is simple. Seems I just have to peddle a little bit more which will make up for any any disadvantage not carrying the board would cost me.
Bob to answer your question I like the heavier weather sailing (10-20 knots) if I can get it but mostly it is in the 0-10 knot range at this time of the year when I get the time to get out there....Pirate
PS..Stop by some time and I'll take you out and show you Mickey and I will take you up on that at a time in the future Bob

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Master of the galleon 'Pirates Lot'

I always wondered when to fit the daggerboard and when not, so I asked ChrisJ, who has alot more experience with the AI than me, at the weekend. As he said earlier, his rule of thumb is when it's time to furl the sail, it's time to install the dagger. This sounds like a pretty good rule to me, but I'm think'n that the turbo blades would have to give better resistance to sideways slip than the dagger anyway. I just roughly measured the surface areas of both and the 2 tubo blades combined have about 20% more surface area than the daggerboard. So, I'm think'n that if you do have sidways slip, the only advantage of using the dagger over the drive is that it's quicker to install. When sailing with the drive in place I always have the blades vertical, but I'd like know though what has more drag, the drive or the dagger.

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Don't take life too seriously................it ain't permanent.

I find the daggerboard essential in any wind to get the AI to reasonably point high. Pointing high is really not the AI's (or any trimaran's) strong suite. On the Lake I have been recently doing most of my sailing, I must tack to get to the other side, so pointing ability is key.

Another tip when sailing up wind is the art of tacking on wind shifts. In most parts of the world, the wind direction oscillates back and forth a little. Use your compass or a bearing on the horizon. Trim to your close hauled point of sail. Then, if you get knocked, tack. Then, on the other tack, you will be "lifted." This allows you to sail much less distance to get to your upwind position.

Also, in wind gusts, I can trim in a little more and point a little higher without an unreasonable sacrifice in speed, or VMG. Then, in a lull, sheet out just a bit pointing down just a bit for a little more speed.

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jzk

Hobie Adventure Island.

[youtube]http://www.youtube.com/watch?v=pTIq7IhU84Y[/youtube]

This seems to be the opposite of sailing logic.

On most boats (and I believe this includes the AI) you want the dagger fully down in lighter air and reduced as the speed / wind increases. You can sweep the board aft in higher wind.

Its a bit like airplane wings... slow planes use big, fat foil wings. Higher speed aircraft use shorter, narrower and thinner air foils.

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Matt Miller
Former - Director of Parts and Accessory Sales
Warranty and Technical Support
Hobie Cat USA
(Retired 11/7/2022)

A centerboard or daggerboard (interestingly, the AI board can be used as either) is used upwind to prevent leeward movement. It is used in both heavy and light air.

Racing sailors raise the daggerboard going downwind leaving only a small section of it down to aid in steering. The AI benefits from a little daggerboard down wind also.

But, again, the daggerboard is always used upwind.

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jzk

Hobie Adventure Island.

[youtube]http://www.youtube.com/watch?v=pTIq7IhU84Y[/youtube]

For a bit of background...

A daggerboard is typically raised and lowered in a vertical direction in a "dagger well"

A centerboard pivots / retracts on an axis.

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Matt Miller
Former - Director of Parts and Accessory Sales
Warranty and Technical Support
Hobie Cat USA
(Retired 11/7/2022)

Back in 2007-8 three of us would go out sailing weekly, with sometimes a fourth. We had lots of fun "racing" and got to tweek things to gain what little edge we could find (when to use daggerboard, fins up/down, even barber hauler, trim). The best (and most fun) way I know of to learn.

If you almost always end up in the rear, you are not doing it as well as the guys in the front!

On my favorite pic below, I'm in 2nd and gaining fast! (#4 is way back off the pic)

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Hobie Island Sailing since 2006

Out of interest, is there an recorded top speed for AI. A chap was looking at mine the other day and said they were good for 20 knots!
I can't see it myself, but I would be interested to hear other peoples views.

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Either lead, follow, or get the hell out of the way!

If you can minimize the water resistance, and the wind and waves are just right, you can really get going.

In 2006 here in Maui (a month after getting my AI's) I got just the right conditions one day with many fast runs many 22's & 23's and finally a 28mph run on the GPS. Fastest seems to be when the wind created long wind waves (miles long). I just sailed along the tops of the waves, with less water resistance. I later found the readings were a little high from the gps bouncing around (I didn't have it mounted yet). I also found on returning home that a Small Craft Advisory had been added after I had left for my sail.

I no longer try that as I've had discussions about what would happen if something broke at that speed (thanks dear).

Above about 10mph the hull hums from planing.

Since the beginning of 2007 I've kept a log with statistics.

09/22/2007 - Three of us were sailing a beam to broad reach doing 8-9mph when a VERY strong steady gust came for over a min. pushing all three of us (in formation) to 19.7MPH! We could see each others boats but couldn't see each other because of the spray off of the hulls reaching at least 1/2 the height of the mast!

That's my two big wind stories, On sailing trips (not fishing) I try to break 10mph. In good conditions I average over 5mph including drifting during snacks and lunch.

My log is posted here:http://www.kayakingbob.com/sailing-log

2009 has been a slow year so far for getting out sailing, between extremes in winds (too little to sail or small craft warnings), My sailing partner getting a knee replaced, his wife (3rd AI) with back problems, and then a long trip "off island".

With a new GPS I bought on my trip I can now even save and show the "Track" of each adventure! (click on "Track", for either of the top two newest entries in my log)

Enjoy, go fast, but be safe!

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Hobie Island Sailing since 2006

Sorry, I should have specified that when I suggested the centreboard was necessary at about the same time as you need to furl the sail, I meant with the drive in. I only sail occasionally with the drive out and then usually downwind in a good breeze and then I leave the centreboard in. As AI Kube said in a recent post, pedal-sailing is a whole new paradigm. PS: Matt, thanks for clarifying the definition of daggerboard and centreboard. Hereafter, I will only refer to it as a centreboard (centerboard in American).

Bob, It's interesting that in your photo of everyone going flat-chat in an obviously stiff breeze, you have your sails unfurled (or is the boat in front slightly furled?).

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Chris, on that pic. the wind had just increased where we needed to reef some, you can see the front red AI is burying it's ama by the short wake on that side. My long wake is me "cheating" by planing off my sprayskirt instead of reefing to catch him.

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Hobie Island Sailing since 2006

Yeah, you look like you might be "hiking out" a bit to windward too .

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