If there are suficient conditions to deploy the jsd, then the end depth will almost always be <50ft alowing the jsd not to curve at the end. Also, the forces of wind and sea state acting on the bouy will keep the cord taugt enough not to alow it to come into proximity of the drogue to become fouled. Also you would atach with a release clip to allow the bouy to jetison itself if it were to incour the load of the jsd due to picking it up.
Sialingdog, your posts got a few gears turning, and I think that I have come up with a solution that we can all swallow. No trailer bouy, just simply detatch the end of the jsd from the boat when you're done, atatch a fender to the boat end, come about to weather, bow load the jsd under power to relieve the load on the drogue, and speed up the retrieval process. Or, if you're single handing, load from the cockpit after securing the fender like you would a mooring. If cockpit loading I would however aproach the fender slowly and while rerieving keep the drogue end about 10 to 15 feet off the beam to avoid fouling in the prop if excess slack ocours. "What say you to that?"
Although I haven't tried it, I have heard of using a polypropylene trip line for a series drogue- the thing being that it has to be long enough so as not to interfere with the drogue (1.5 to 2x drogue length)
I haven't tried this method in "the big stink" as some would say, but I have experimented with it in 40-45kt and 15-18ft seas, and it worked like a champ.
Quote:
Originally Posted by sailingdog
You obviously don't have a clue about how the JSD is supposed to work. Buoying the end of it will effectively stop it from working properly because it will introduce slack into the JSD where the JSD curves up to meet the buoy. Most JSDs are 170'+ long, and are designed to hang almost straight down from the transom of the boat under certain storm conditions, and as the boat gets pushed by the waves, it straightens out and progressively loads up the cones... having a big catenary curve in the JSD will prevent this from working properly. Also, you run the risk of having the JSD foul itself or the buoy line....
So wait, the guy that has never deployed his JSD in adverse conditions is telling the guy that HAS deployed his in 40-45kt and 15-18ft seas that he doesn't have a clue? Now that's funny.
So, close, is the drawing below basically what you're talking about? I could definitely see how this would make retrieval much easier.
As for "stopping it from working", Dog, I thought the only time the JSD will hang down vertically is when there is no load on it (i.e. - no forward motion). This is what Newton would posit anyway. So if the thing's hanging straight down in "certain storm conditions", you might be in trouble, or vastly overestimating the conditions.
It seems to me that depending on the weight at the end of the drogue, and the length of the light line, you shouldn't see much degradation in performance...at least from a physics standpoint. And it wouldn't necessarily cause the tangling that a trip-line from the stern along the main line would cause (at least not while under load).
Furthermore, as conditions calmed, wouldn't the JSD still sink down vertically, drawing the buoy closer to the boat as well?
Smack, the drawing is basicly correct. Also I can't see an anchor bouy on a light line being able to introduce slack into a drouge that under storm conditions is under the load of (in my case) a 46' steel hulled cutter doing 6/7kt being propelled by both wind and sea state congruent with such conditions. Heck, I'm not sure that a chanel marker could even acomplish that, though it may snap the line.
You had also mentioned something about a "Gale rider" earlier. The galerider is a pretty sweet little weapon for active downwind sailing when you start to get into a situation where broaching begins to become a concern. It won't slow you down as much as a jsd, but will provide sufficient resistance to broaching, and relieve the helmsman from some of the more heavy steering involved in that kind of sailing, and because of it's ability to let you move faster downwind it relieves pressure on your rig b/c of the decrease in aparent wind.
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Charles
S/V In Anion
Cape Fear, NC
Okay - I just had a conversation with my genius physicist nephew over the holidays (the one that gives talks in Copenhagen and stuff) - and, as much as I'm writhing on the ground as I write this, I think maybe Dog is kinda, sorta "right" about the JSD....at least in principal.
My biggest concern with the concept was rudder damage due to water (either in the wave itself, or breaking at the top of the wave) moving past the rudder creating a reverse force on it and breaking stuff. This obviously would not be an issue if the boat was bow-on. So I just wasn't quite sure about it.
However, my smarty-pants-physicist-nephew corrected my thinking that waves in water are actually "moving forward" as they appear to be. Though he rightly said the full details were way beyond my severely limited mind, he explained that the standard non-breaking wave is simply an up/down movement of the water - not the forward motion that it appears to be. And that forward "surfing" motion of the boat is due to its sliding down the face of the wave - it's not really being "pushed" because this type of wave has no velocity, just amplitude. (I think that's all right).
SO, in this instance, the JSD is golden.
He went on to say that breaking waves were a completely different set of equations that got very complicated very quick. That water IS moving and has a lot of "forward force". But, as someone said earlier in this debate, as long as the rudder stays in that lower "strata" of water, it's fine.
There may be other Fluid-Dynamics-Gurus on here that can shed more light on these DiffEqs - but that's what I understood him to say right before I fell asleep in my bowl of Cheetohs.
So - now this only leaves the issues of the breaking waves pooping the JSD'd boat, or the boat tilting up high enough on the wave face to expose the rudder to breaking water.
This is really pretty fun to think about. Oh look...cheetohs.
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"The sail, the play of its pulse so like our own lives: so thin and yet so full of life, so noiseless when it labours hardest, so noisy and impatient when least effective". -- Henry David Thoreau
"standard non-breaking wave is simply an up/down movement of the water"
Doesn't really matter. The boat is moving in three dimensions and three axes (up/down, left/right, back/forth, yaw, pitch, roll) and it doesn't matter where or which relative motion impacts the rudder. If the rudder gets moving "broadside" to the water instead of "forward" through it, the whole force bends the rudder post (or snaps it) instead of letting the rudder cleave through the water.
Considering the loads that can generate, and the costs of beefing up rudders and posts, and that MOST rudder posts are stainless steel suffering from potential crevice corrosion because stainless just isn't suitable for that application...It isn't surprising they go SNAP every once in a while.
They probably should all be bronze, but who would pay for it? BendyToy has a nice idea using carbon fiber, but that can be problematic too. Like the Airbus that lost a tail.
Part of the reason the JSD works as well as it does is that the design essentially eliminates the chance of it becoming completely unloaded, which is part of the problem with retrieving it. As long as there is some load on the JSD, it will keep the boat oriented properly, especially as the load progressively increases as the forces on the boat increase.
BTW, Great White, the blog you're linking to is mine.... and I'm a strong advocate of the Jordan Series Drogue.
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Sailingdog Telstar 28
New England
You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.
—Cpt. Mal Reynolds, Serenity (edited)
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As long as there is some load on the JSD, it will keep the boat oriented properly, especially as the load progressively increases as the forces on the boat increase. 
