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Old 18-02-2008, 11:04   #1
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David, hydraulic steering is often installed on vessels that do not require 'power' assist. My Cartwright 36 pilothouse had it because it is ideally suited to multiple steering stations. The boat herself, however, was extremely well balanced and could be steered easily with the hydraulics off and the emergency tiller in place.

Hydraulic steering is also used on my cat, again not because the vessel requires a 'power assist', but because it is also ideally suited to having one wheel operate two rudders. Properly engineered hydraulic steering systems may reduce 'feel' (less relevant in a catamaran anyway), but they are both extremely strong and reliable (and certainly more so than the ubiquitous cable systems used in so many boats).

Is there a point at which hydraulic steering becomes a necessity? No doubt, but that would no doubt be contingent upon the anticipated steering forces more than length overall, or displacement. In any case, it is bound to be on a boat much larger (or much more poorly balanced ) than I would ever own.

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Old 19-02-2008, 03:09   #2
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BTW I don't mean to make any significant storm sound trivial, I am aware of the awesome power of nature - I am just trying to find the best possible way to prepare for such events. The outcome depends on foresight, preparation, knowledge and God.
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Old 19-02-2008, 05:00   #3
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Wotname, when fully deployed the Jordan series-drogue slows the boat to 1 1/2 knots (approx.) and does not require any steering imput. As to sea room, boats with properly deployed para-anchors will also drift - you cannot overcome the effects of current.

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Old 19-02-2008, 16:44   #4
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Thanks Brad, I wasn't aware the series drogue would allow the boat to "self steer" and not require some helm input. Must have missed that bit in my reading. I can sort of see how it might work - a big arm keeping the stern of the boat to windard as it sails downwind very slowly.
Pardey's experience seems to suggest 1/4 to 1/2 knots of drift - and I realize this will depend on boat design etc. But that is still at least 3 times slower.
Again we are talking speed through the water due to wind forces acting on the boat.
Current will have the same effect on searoom using either system.
There are still the concerns of reducing the prospect of breaking seas around the boat and the general stability of a boat hove to compared to a boat still making way downwind. I am talking Monos again as they can roll substantially when running (even running slowly). I can't see (yet) how a series drogue would prevent such rolling.
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Old 19-02-2008, 16:51   #5
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The Pardey's have a DVD called Storm Tactics that shows what they are talking about. I have watched it several times and tried heaving to once in 40kts of wind with 12' white caps on lake Michigan. The slick was there and the boat rode very well just as it showed in the DVD.
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Old 19-02-2008, 20:10   #6
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L & L's book is sitting right in front of me. My friend gave it to me, and I started reading it yesterday. What I liked most was that it not only solidified in me that "yes, being hove to works in anything that the ocean can throw at you [perhaps with a sea anchor to assist]", but it also addresses why people don't do it as much any more.

To be honest, I think this is another reason that "bluewater" boats tend to have full-ish keels. If there's a slam dunk storm tactic that only works well with big keels, you really should be justifying in your head why you have a fin.

The other thing that I agree with is the reason why people don't heave to at the right time: bad seamanship. You start by running off, which tricks you into thinking the wind isn't as fast, because you're probably scrubbing 8kt+ off your apparent. That's a sizeable amount of wind.

So there you are, on a run, with 30 knots apparent, and *then* you decide to heave to? You're going to come about into 38 knots of wind and get slammed into the water. And if you're on a bare poles run, it's going to be even trickier.

Heavy Weather Sailing shows that there are a variety of ways to survive a storm. There are different tactics for different types of boats, and different types of crews.

But for my money, I sleep well knowing that with a big keel the only thing I need to work on is my seamanship and maybe a $50 parachute.
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Old 19-02-2008, 21:12   #7
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But for my money, I sleep well knowing that with a big keel the only thing I need to work on is my seamanship and maybe a $50 parachute.
Hello RH, good to see you survived the "THUD", why don't you let us know what happened rather than reading L & L's book .

BTW the their DVD is pretty good also.
Not sure if you can get a $50 quality parachute that will be strong enough for a para-anchor. I know that L & L talk about BOURD surplus but I haven't been able to source anything like that in Aussie. Let me know if you can get one in good old USA - I might want to buy it off you .

I understand that the full keel is not essential for this tactic to work but it probably won't work with a really narrow fin keel.

Irwinsailor - good to hear another first hand experience of the "slick"; thats two now. I know that 40 knots and 12 ft seas are not massive but from that experience, would you now plan to use this tactic in worse conditions or not. I am assuming you were just hove to, no para anchor deployed.
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Old 20-02-2008, 12:44   #8
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Quote:
Originally Posted by rebel heart View Post

The other thing that I agree with is the reason why people don't heave to at the right time: bad seamanship. You start by running off, which tricks you into thinking the wind isn't as fast, because you're probably scrubbing 8kt+ off your apparent. That's a sizeable amount of wind.

Been there, done that with winds that went from 30 to 50 before I really noticed it.

So there you are, on a run, with 30 knots apparent, and *then* you decide to heave to? You're going to come about into 38 knots of wind and get slammed into the water. And if you're on a bare poles run, it's going to be even trickier.


That depends on the boat and how much canvas is up. I had to come about in 60 knots of breeze with the Staysail and a single reefed Main once. I had to sheet out the Main completely and let it flog till we got around but we did get around. Needless to say, it was a VERY quick turn.

It's all about the boat and the seamanship.
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Old 20-02-2008, 13:01   #9
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Quote:
Originally Posted by rebel heart View Post
L & L's book is sitting right in front of me. My friend gave it to me, and I started reading it yesterday. What I liked most was that it not only solidified in me that "yes, being hove to works in anything that the ocean can throw at you [perhaps with a sea anchor to assist]", but it also addresses why people don't do it as much any more.

To be honest, I think this is another reason that "bluewater" boats tend to have full-ish keels. If there's a slam dunk storm tactic that only works well with big keels, you really should be justifying in your head why you have a fin.

The other thing that I agree with is the reason why people don't heave to at the right time: bad seamanship. You start by running off, which tricks you into thinking the wind isn't as fast, because you're probably scrubbing 8kt+ off your apparent. That's a sizeable amount of wind.

So there you are, on a run, with 30 knots apparent, and *then* you decide to heave to? You're going to come about into 38 knots of wind and get slammed into the water. And if you're on a bare poles run, it's going to be even trickier.

Heavy Weather Sailing shows that there are a variety of ways to survive a storm. There are different tactics for different types of boats, and different types of crews.

But for my money, I sleep well knowing that with a big keel the only thing I need to work on is my seamanship and maybe a $50 parachute.
I think this is a pretty good analysis of heaving to.

I also agree with RebelHeart on the full keel idea. If you've got a fin (or modified fin like I had on my last boat), you stand more of a chance of tripping over that fin as you slide sideways down the breaking waves. In any case, it's going to push your rail way down toward the water as you fly sideways down a wave.

Take away the draft, and you end up more able to just slip down the faces sideways without tripping, staying mostly upright.

Well put.
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Old 23-02-2008, 14:51   #10
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...
I also agree with RebelHeart on the full keel idea. If you've got a fin (or modified fin like I had on my last boat), you stand more of a chance of tripping over that fin as you slide sideways down the breaking waves. In any case, it's going to push your rail way down toward the water as you fly sideways down a wave.

Take away the draft, and you end up more able to just slip down the faces sideways without tripping, staying mostly upright.
....
I can't see how this could be accurate. A typical fin keel boat will have much less wetted area than full keel boat. It is the wetted area that produces the drag going sideways. The fins make much of their lift from their shape going through the water. If the boat is going sideways, then the fin will not add lift. It seems like the order of 'tripping over' while being pushed sideways would be (least to most) multi-hull, fin-keel, full keel.

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Old 24-02-2008, 07:39   #11
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I can't see how this could be accurate. A typical fin keel boat will have much less wetted area than full keel boat. It is the wetted area that produces the drag going sideways. The fins make much of their lift from their shape going through the water. If the boat is going sideways, then the fin will not add lift. It seems like the order of 'tripping over' while being pushed sideways would be (least to most) multi-hull, fin-keel, full keel.

Paul L
Hi Paul.

I'll try to explain the way I (and I think rebel heart too) are seeing it. By no means have I "been there" and "done that" on any of these boat types you listed in order of trip-ability, so it's only theory. I have not been in conditions sufficient to warrant the use of sea anchors or drogues in any of the 3 types mentioned.

Envision the 3 types of boats, sliding sideways down a wave (hopefully you are in control and using drogues and sea anchors instead!!).

Now, if you first picture the catamaran with boards up and rudders too, if possible, you have a very flat hull shape that will slide down beam-on waves almost as well as it would going down them bow first. It's basically skipping like a stone, right?

Now push the down-wave centerboard down on the cat, while she is skidding sideways down a wave. (if taking a wave from port and skidding down the wave in a starboard direction, lower the starboard centerboard). What happens? The way I see it, is the area presented to the water in the form of the newly lowered centerboard serves to slow the boat's motion, but in doing so, creates more rotational forces that bury the starboard hull and cause the port hull to lift (given sufficient wave heights and steepness). Would you agree with that? In the cast of the cat, it's pretty catastrophic. It would be a bad error in cat handling.

Let's move onto the full keel boat. The full keel is typically running the length of the boat, but draws a comparatively small amount of water, right?

Now if you picture this hull shape sliding down the wave in the same way the cat did from our last example (save wave orientation, same slide direction, everything the same except the hull shape), what you have is a boat lying to its side due to the "centerboard" or in this case keel, dragging through the water. At its maximum angle of heel due to water pushing on the full keel, the boat will rotate to its starboard side until such a time as the full keel is up out of the water enough to not produce any more of the force that is rotating the boat to starboard in this slide. This angle of heel will be relative to how deep the keel is, because as you rotat the boat to starboard, you will present less and less keel to the oncoming "apparent current" that is pushing on the keel, and tipping you starboard. Kind of like when a boat heels a lot in a puff of wind, and the force produced by the wind is lessened due to that heel. Would you agree so far?

Now let's move onto the fin keel. Put that hull shape in the same situation. What happens? The same thing as with the full keel boat. The boat lists to starboard until the rotation is sufficient enough to be presenting none of the keel to the "apparent current" (which is induced by the boat skidding down the wave). So, if a full keel boat draws 3 ft, an angle will be set up which rotates the boat until that 3' is not directly in the current induced by sliding down the wave broadside. Same thing happens in the fin keel boat. It rotates until the keel isn't presenting its area to the induced current, right? Well, if the keel is 6' or 8' or something like that, the boat will have to roll a lot further starboard in order to achieve the balance of skidding its way peacefully down the wave broadside while presenting no keel area (or little keel area) to the current induced by the starboard slide.

So what I'm saying is that the fact that a fin keel is longer (has more draft) than a full keel, means that the boat will have to rotate starboard to a greater degree, futher increasing the risk that the boat will trip on its rail and result in a complete knockdown. All theory, but I'm not sure who of us has been out there to test it??
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Old 24-02-2008, 08:09   #12
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PS: I am envisioning that the boat might be "side surfing" rather than just pleasantly drifting down the face of the wave in the above post. This is why the area presented by the keel would become more important than wetted area in this example.
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Old 19-02-2008, 21:15   #13
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In regards to the parachute pricing, I've seen a few for around $50 or so at our marine swap meets around here, but I'd need to really investigate them to determine quality.

I answered the thud thread! (finally!)

Isn't the entire reason for using the sea anchor when hove-to to keep the bow 50 degrees off the wind? It seems like the trough / crest wind differential is what causes the hove-to position to fall apart, since it's two different winds at that point. They make a reference of that in the idea that bigger ships would heave to with their topsails, to negate the trough / crest situation.
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Old 20-02-2008, 06:25   #14
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Isn't the entire reason for using the sea anchor when hove-to to keep the bow 50 degrees off the wind? It seems like the trough / crest wind differential is what causes the hove-to position to fall apart, since it's two different winds at that point.
I understood the main purpose of the sea anchor was to prevent the boat fore-reaching while hove to and thus sailing out of the slick. The sea anchor also creates its own turbulence adding to the slick even further to windward.

Everytime I re-read Storm Tactics I find new information. It is cramed with sensible data and argument. IMHO.
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Old 24-02-2008, 00:50   #15
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Troutbridge, you make a good point about the difficulty in coming about if the cockpit is being overwhelmed by breaking waves while streaming your series-drogue. And while I am certainly hoping that this is never necessary, I could forsee a situation where it would be. One would have to time their maneuver and have both engines running hard, but to the extent that there are some proponents of lying-ahull in cats, they should be able to safely come about even in dreadful conditions. Indeed, as we know Richard Woods boat, despite being only 32 feet overall, survived after he was rescued and one would imagine it was taking seas off the beam much of the time.

Another option, as you mention, is retrieving some of the series drogue in order to increase speed and lessen the impact of the waves. In order to avoid the impact of breaking seas, I suspect that this would require accelerating the boat significantly and hence, the drogue would no longer be a 'passive' defence, but one requiring constant attention to the helm.

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