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Old 18-02-2008, 10:17   #16
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David M, Ramona gives one valid reason for the series-drogue, but there are many others:

Secondly, the boat still maintains some forward motion and hence (as when you are sailing downwind) the apparent speed of the wave and wind from behind is lessened.

Thirdly, with a series - drogue, the drag remains essentially constant as the cones are deployed throughout the length of the rode. In sea-anchors, there have been numerous cases of the chute collapsing in an incoming wave: in such a case, the rode goes temporarily slack and then suddenly re-fills, causing a huge snap and extreme forces on the rode and the attachment points on the yacht. This can tear hardware out of the deck; the chafe can also cause the rode, the bridle or even the chute to break. Richard Woods felt forced to abandon his cat a couple of years ago in precisely these circumstances. Yes, there have been opinions expressed that he had not let out sufficient rode, but some would suggest that this only highlights a further difficulty with sea-anchors: they are much more difficult to deploy (and retrieve) and may require adjustments to ensure that the sea-anchor is on the same relative position on the wave train as the boat. In extremely high waves, if the boat is situated on a crest while the sea-anchor is below the trough, there will be a tendancy to pull the anchor up towards the surface as well as back, making it more vulnerable to the effect of breaking seas.

Fourthly, temporary slack in the rode can also allow the boat to yaw and take the brunt of the waves beam-on.

Fifthly, there is a natural tendancy for a boat to maintain a more straight heading if it is moving forward with some drag behind. This is the direction that boats (and arrows) are designed to travel in.

Sixthly, it is much easier and safer to deploy a series-drogue as it can merely dumped out from the relative safety of the cockpit, rather than from the bow(s).

Seventhly, the USCG conducted tests of Jordan's design a number of years ago and found them more effective in breaking seas than a sea-anchor.

Eighthly, it is comforting to know that Jordan made his design available free of charge to hundreds of people/sailmakers worldwide; his original intention, the original test by the USCG and the testimonials are not merely sales hype by a manufacturer.

Having said all of that, there is more than a nugget of truth in your expressed concern about breaking waves into the cockpit of a multihull. While the stern of a modern cat should contain sufficient bouyancy to rise with even large oncoming waves, breaking seas are a different phenomenon. Cats tend to have huge cockpits and some have a step down into the bridgedeck accomodation that would no doubt allow entry of water before the cockpit drains could even begin to deal with the situation.

For precisely this reason I have purchased both a series-drogue and a para-anchor. While it is my fervent hope that I will never require either, I see the first line of defence as being the series-drogue. Although the manufacturer suggests deploying the entire length and then going below and forgetting about it, I would initially deploy a shorter length with the intention only of slowing the boats progress and increasing lateral stability. If helming became impossible (or too tiring) I would prepare the sea-anchor for deployment and then pay-out the entire series-drogue and basically 'see what happens'. If, as Jordan and others claim, the boat slows to about 1 1/2 knots and is able to take even breaking seas without difficulty, I would indeed go below and ride it out. If, on the other hand, the cockpit was getting overwhelmed by breaking seas, I would release the series-drogue and deploy the sea-anchor from a bridle off the bows.

I suspect that a monohull with a high bridgedeck, solid companionway doors and adequate cockpit drainage would do well (in fact much better) with a series drogue than with a para-anchor. I also suspect that the same would be true in cats with no cockpit wells and with an open rear bridgedeck (or alternatively, with slats under the cockpit area). I am less than confident about how my particular cat would survive in those conditions as I have a distinct cockpit well that is (partly) fenced in by a raised deck to accomodate the aft athwartships double berths.

In the end result, what works for some may not work for others. Boats differ, as do storms. What works for a ship or supply vessel will likely have little application to a small sailing yacht. What works for a Westsail 32 (lying ahull - the Westsail 32 in 'The Perfect Storm' was actually found upright and intact several days after the rescue of the crew) may not work for a comparatively light fin-keeler or multihull. Indeed, as I have already suggested, what works for one cruising cat may not work for another.

I suspect that there are variable answers for tactics in coping with extreme conditions, precisely because there is no single 'correct' answer. That, of course, is disquieting. We would all prefer that there be a single right way to deal with a situation. We can (and should) read about the experiences of others; but ultimately, as with virtually everything to do with the sailing and navigation of a vessel under our command, we have the responsibility to adjust to varying conditions as they arise. Develop a plan, but keep an open mind. And equip and prepare your boat for the possibility that your designated first line of defence may fail.

Brad
A series drogue sounds like the thing to have. I have used one in fact but for a completely different reason and that was to put a big load on a 150 meter long acoustic array to keep it horizontal and to see if it would break. I never questioned the validity of a series drogue. I questioned the validity of putting a boat stern to into ocean swells. I never said that it could not be true.

I am still trying to imagine how a sailboat could have any effect on breaking ocean swells that weigh hundreds of thousands of times more by putting the swells on the boats quarter thus creating some leeway generated turbulence. I don't doubt it is possible because I am trying to keep my mind open but the concept totally evades me.

As far as dumping oil...that makes sense. Oil would absorb energy at the oil water interface plus affect surface tension of the water, both causing a dampening effect. It's an old mariners trick.

I'm not saying anyone is right or wrong...I am just trying to understand the concepts.
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Old 18-02-2008, 10:23   #17
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David, if that were the only reason I might agree. Although locking your helm on the centre-line is no easy matter if your boat is being forced backwards and slewing somewhat to the side in breaking waves. Certainly I would not rely upon the standard brake in an Edson pedestal, for example. Even with hydraulic steering/lashings, the forces generated would eventually create some play that would only exacerbate the situation, leading to even greater forces as the rudder moves off the centre-line.

While to you this seems crazy, there are some sound reasons for the series -drogue. At its simplest, they work because boats tend to have greater lift from the stern than the bow, and because boats are designed to move forwards rather than backwards.

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Old 18-02-2008, 10:29   #18
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I have...plenty of times with a semi-balanced rudder on a sailboat. I did skippered charters for a sailing school on the weekends while at the maritime academy. What is the problem with putting the rudder amidships and locking it during a storm? If the rudder post fails by bending or breaking off then I would say that is an undersized rudder post. Shouldn't the steering gear on a serous ocean cruising sailboat be designed to withstand the forces generated by a storm?

It seems crazy to have to put a boat stern to into breaking waves because one might have an undersized rudder post, an under-balanced rudder or a poorly designed steering system.
Dave, you answer your own question. It the boat is not up to the task do you really want to be out in bad weather? Look at how the boat is built, scantlings, hull flange joint, keel connection,......

For us the thought of towing a drouge when running off is frightning. The loads impossed on the steering gear would be very high. I would rather not tow anything and let the boat run under bare poles. Wave trains move at what 15 knots or so? As long as we have room that is our game plan.

Each and every boat needs a way to deal with weather, strategies may be different from boat to boat though.
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Old 18-02-2008, 10:38   #19
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Joli, I couldn't agree more. One word of caution about running with a storm, however: despite the experiences of Dumas, Moitessier and others, it requires a great deal of sea-room and if things get bad enough, there is a very real risk of pitchpoling, even in a well-designed and constructed yacht (read the Smeetons 'Twice is Enough', if I remember the title correctly). At some point you may have to slow the boat down, and that is where drogues and sea-anchors come into play.

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Old 18-02-2008, 10:39   #20
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This is amounting to naval architects designing steering systems that can handle 99% of the situations that a boat will encounter. I don't know if there are economic reasons for this but there probably are as with all things. Would it take that much more money (and weight increase) to increase the scantlings and design of a steering system so that a yacht can go bow into breaking ocean swells with a nicely locked up rudder? Storms are a part of life for a mariner. It would not take Hercules to turn a rudder with a 60/40 balance even if going backwards at a few knots.

Just curious, at roughly what length does a sailboat need powered hydraulic assist to steer? In seascouts we had a 104 foot twin screw powerboat that had human powered cable steering. Old sailing ships had human powered rudders of course, but in all practicality, how about modern sailing vessels?
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Old 18-02-2008, 10:46   #21
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This is a tough 'armchair' question. We've all read what works for different folks. I would imagine you pick the story with the boat that most resembles yours and hope for the best.

As for catamarans, I believe the definitive story is the Queen's Birthday storm. Lie ahull, get yourself tied down in the salon and hold on until the ride is over.

However, this advice is of little use when there's the possibility of a lee shore.
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Old 18-02-2008, 10:52   #22
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This is a tough 'armchair' question. We've all read what works for different folks. I would imagine you pick the story with the boat that most resembles yours and hope for the best.

As for catamarans, I believe the definitive story is the Queen's Birthday storm. Lie ahull, get yourself tied down in the salon and hold on until the ride is over.

However, this advice is of little use when there's the possibility of a lee shore.
abeam? ..whats the advantage?
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Old 18-02-2008, 11:04   #23
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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 18-02-2008, 18:25   #24
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abeam? ..whats the advantage?
David, I believe I've posted this in the past, but in case you missed it

The Queens Birthday Storm
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Old 19-02-2008, 03:02   #25
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I think we need to differentiate between Multis and Monos. They obviously quite different machines and react very differently in the water. From the literature I have seen, a series drogue appears to make a lot of sense for a Multi. I am not so sure about a Mono, and the rest of the post refers only to my thoughts on Monos.

I agree with the comments about para anchors possibily collasping and putting large stains on rodes, anchor points etc. The Pardey's go into some detail about the length of rode in relation to wave lengths etc to keep the para anchor "filled". This would need to be monitored as conditions change.

I have a few concerns about series drogues for a Mono. With a stern drogue, the boat is still sailing downwind and needs to be steered (manually or otherwise); in essence you are still underway and require more input (and energy) from the crew to sail the boat; you are using up searoom at a much faster rate; you are probably travelling with the storm thus prolonging your exposure. A drogue does not alter the sea state and breaking seas still have to be contended with. Likewise the risk of broaching, while reduced, is still present and this threat increases as fatigue increase.

A para anchor set from the bow seems to have significant inherent risks also. Most are already mentioned by others on this thread.

Hove to (under sail / rudder angle alone) seems to be OK except for the risk of breaking seas - and to me that seems to be a very significant risk from the handfull of breaking seas I have seen in the Tasman sea. I am assuming the design of the boat allows it to be hove to satisfactorly.

However setting a para anchor on a running bridle from the bow and quarter while hove to seems to overcome most of the risks providing the boat can be kept inside the protection of the slick and the postioning of the para anchor is maintained relative to the wave length. Yes, that will require monitoring and so will chafe issues but the boat is now (supposedly) free from the threat of breaking seas, capsize, pitchpoling, riding the seas comfortably, not underway, fairly stationary while the storm is moving away and in general, providing a safe haven for the crew to rest in. The key to the whole thing appears to be the existence and effectivness of this "slick" - to prevent the seas immediately to windward from breaking. I know some of you doubt it effectivness - and I doubt it a bit too - but although I don't understand (yet) how it works, I am starting to believe it must, if significant sailors report that it is true.
Sounds to be good to be true doesn't it. That is why I keep asking for first hand experience to confirm (or otherwise) the theory. So far, the only first hand accounts I have found are the Pardey's.

I may be able to post my own experiences here one day as I am planning to experiment with this (in a safe manner) as soon as I am back on the water.

Thanks to Irwinsailor for starting this thread and to everyone else willing to share their thoughts and time so far.
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Old 19-02-2008, 03:09   #26
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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   #27
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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   #28
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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   #29
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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, 18:00   #30
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Just curious, at roughly what length does a sailboat need powered hydraulic assist to steer? In seascouts we had a 104 foot twin screw powerboat that had human powered cable steering. Old sailing ships had human powered rudders of course, but in all practicality, how about modern sailing vessels?
Dave, we're 65k pounds with a semi balanced rudder and the helm is feather light in all conditions. We can actually put a bungee cord on the wheel and she'll sail all day long like that, up, down, and various sail combos. The boat has a fin keel and balanced rudder with cable steering and hyd ap.
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