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  1. #101
    VO5 is offline Registered User
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    Part 2.

    Obviously, the surfer uses body weight and posture to achieve the effect of stern down and bow up.

    A vessel in a large following sea must replicate this posture so that on reaching the trough at the bottom of the wave face, its bow does not dig in.

    My findings are, over several deployments, to achieve this requires pull on the stern sufficient that the stern becomes depressed and the bow bouyant (in comparison).

    If the towline and its rig (The Seabrake) is too horizontal, the restraint on the crest (at a point in time and position when it is most needed) will not be effective. It will only succeed in slowing down the vessel but not in holding down the stern as well at the same time.

    This can not be allowed to develop as a defect.

    In order to correct this potential defect the stern must be held down beginning when the vessel is on top of the crest and continuing all the way down the face of the wave until the trough is reached, mirroring the result achieved by the surfer.

    Therefore the horizontal angle formed by an imaginary line extending from the the deck and past the stern and the towline (the towline brace) ought not to be too acute, otherwise the effect is for the towline to slow the vessel down, but not to hold the stern down as well when the advancing wave approaches from astern lifting the stern (and trying to get under it and to roll the boat over, worst case scenario, if not on that attempt then with the wave that follows).

    Therefore the same horizontal angle and the angle formed by the towline (the towline brace) should be less acute.

    The consequence of this is that the pull exerted on the stern is more positive
    and introduces the oblique element helping to exert pull AND keep the stern down.

    The angle at which the towline(the towline brace) enters the surface of the sea shoutd therefore not be shallow. This can be immewdiately recognised by the distance of the entry point from the stern.

    As the end of the towline before the connection with the Seabrake is the chain. The towline....does not descend from the brace to the Seabrake in a straight line.

    It descends in a curve.

    This ensures the Seabrake is properly embedded in the sea that follows and when extra pull is exerted on it by the effect of the vessel being lifted to a crest, this towline is stretched taut, in a straighter line.

    This tautness serves to pull the stern down and lift the bow up on the crest of a crest. The boat then surfs / slides down the face of the wave with its bow UP like the surfer on his surfboard. The stern remains down. The possibility of knocking the vessel off course is avoided. The vessel now maintains directional stability as well.

    Guidelines for the length of chain and its calibre for different vessels is privided by the manufactures.

    In heavier seas I personally prefer extra weight, so I have extra lengths I can shackle on to ensure depth of the Seabrake is maintained.

    In a previous post on this thread there is an attachment to a report of a test carried out on the Seabrake with the unsatisfactory result of it being towed behind a vessel and it breaking surface.

    The test was carried out in Chesapeake bay.

    Chesapeake Bay is a shallow inland sea in the Untied States.

    It is not suitable for testing this type of rig because it is too shallow.

    The rig should be deployed in water DEEPER than the length of the towline at least, and then it should be WEIGHTED PROPERLY.

    Notwithstanding my immediate comment above, it can be used in shallower water, but with care that it does not foul the bottom, and, in any event, that it is weighted properly.
    Last edited by VO5; 30-09-11 at 23:40. Reason: typo

  2. #102
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    .
    Good grief, is this drivel still going?

    Just to address a few points of obvious error:

    ---------------------

    V05 claims the JSD is 'outdated technology', only used by Luddites. however, the JSD and the Seabrake were both developed in the early 1980s and neither have changed significantly in the interim.

    ---------------------

    V05 claims that the Seabrake should not be used in shallow water, saying that The rig should be deployed in water DEEPER than the length of the towline at least, but on the Seabrake website it says the device is designed to operate just below the surface, 3-5 ft at operational speed of 3 to 7 knots.

    ---------------------

    V05 says the JSD does not provide directional stability. This is rubbish - the JSD provides exactly that, as testified to by all those who have used it in anger.

    ---------------------

    And there are more in among the endless scribblings, but I am losing the will to live.

    - W
    Last edited by webcraft; 01-10-11 at 00:35.

  3. #103
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    Quote Originally Posted by webcraft View Post
    .
    Good grief, is this drivel still going?

    Just to address a few points of obvious error:

    ---------------------

    V05 claims the JSD is 'outdated technology', only used by Luddites. however, the JSD and the Seabrake were both developed in the early 1980s and neither have changed significantly in the interim.

    ---------------------

    V05 claims that the Seabrake should not be used in shallow water, saying that The rig should be deployed in water DEEPER than the length of the towline at least, but on the Seabrake website it says the device is designed to operate just below the surface, 3-5 ft at operational speed of 3 to 7 knots.

    ---------------------

    V05 says the JSD does not provide directional stability. This is rubbish - the JSD provides exactly that, as testified to by all those who have used it in anger.

    ---------------------

    And there are more, but I am losing the will to live. I am afraid I find the vast bulk of his postings on this thread empty noise. Your mileage may vary.

    - W


    Oh Dear ! I am so sorry to hear of your mindstate, Webby.
    I think we all should do our best to cheer you up and try to prevent you from taking your own life.

    There are no errors on my part, I assure you. The errors have to be on your part, not grasping what is meant, which I try to explain by way of the printed word, as clearly as possible.

    The thing is, Webby, the JSD will slow down a boat, granted, absolutely.

    But directional stability depends on keeping the stern down so that the sea following cannot get under the stern to knock it sideways, otherwise the risk is the next wave could roll it over.

    If the stern is not kept down therefore directional stability is not guaranteed.

    It is crucial to keep the stern down on top of a crest first. It needs extra pull to achieve this. The JSD cannot generate that extra pull because the cones exert a constant pull and not an adjusted pull when needed, because they are fixed.

    Have I explained it correctly so you will finally understand, or possibly....I am beginning to think you have no ocean going experience at all ?

    Because If I haven't explained it correctly to you in plain English or you do not understand this basic two pronged principle, I will explain it again, as I am very patient, you see Webby ?

    The Seabrake should not be used in shallow water because it is weighted.
    It can scrape along the bottom either when it meets extra shallows or during recovery, is the reason.

    Gottit ?

  4. #104
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    I though this thread was dead 4 days ago. Obviously VO5 has found a pulse, from somewhere

    Unsubscribing....byeeeeeeeee
    Yachting photographer http://grahamsnook.com/news
    (and boat tester)

  5. #105
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    Quote Originally Posted by snooks View Post
    I though this thread was dead 4 days ago. Obviously VO5 has found a pulse, from somewhere

    Unsubscribing....byeeeeeeeee
    He he . . .

    JSD is usually deployed with a length of chain or other weight at the end. Nylon line plus the fact that the cones are not rigid means that the drag is not constant and is dynamically varied, so once again Shampoo Man is havering.

    JSD keeps the boat's stern dead to wind - no record anywhere in the literature of the 'knocking off' shampoo man froths about.

    The idea that a hundred metres or so of drogue - no matter what it is composed of - could drag along the bottom shows a complete lack of understanding of the physical forces involved IMO. While V05 may have some genuine heavy weather experience his ramblings suggest that he has perhaps survived them more by blind luck than by posessing any grasp of the forces involved.

    Unbeileveable stamina though - 'head and shoulders' above the rest of us, most of whom have long ago lost the will to live while reading this. I promise not to bump it back up . . . .

    Webcraft out . . . .

    - W

  6. #106
    rotrax is offline Registered User
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    Quote Originally Posted by webcraft View Post
    .
    Good grief, is this drivel still going?

    Just to address a few points of obvious error:

    ---------------------

    V05 claims the JSD is 'outdated technology', only used by Luddites. however, the JSD and the Seabrake were both developed in the early 1980s and neither have changed significantly in the interim.

    ---------------------

    V05 claims that the Seabrake should not be used in shallow water, saying that The rig should be deployed in water DEEPER than the length of the towline at least, but on the Seabrake website it says the device is designed to operate just below the surface, 3-5 ft at operational speed of 3 to 7 knots.

    ---------------------

    V05 says the JSD does not provide directional stability. This is rubbish - the JSD provides exactly that, as testified to by all those who have used it in anger.

    ---------------------

    And there are more in among the endless scribblings, but I am losing the will to live.

    - W
    +1!

  7. #107
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    Quote Originally Posted by VO5 View Post
    .... But directional stability depends on keeping the stern down so that the sea following cannot get under the stern to knock it sideways, otherwise the risk is the next wave could roll it over....
    This is true but the JSD remember is lying down the back of the wave. As the yacht approaches the crest, the force caused by the drag of the JSD cones must be downwards (at an angle at least equal to the back slope of the wave) relative to the stern and so pull or hold the stern down.

    Of course, as soon as the yacht starts to accelerate, due to gravity or lift caused by a cresting wave or force by a breaking wave, the forces on the JSD increase (in a non linear manner) and as such due to the direction of the JSD continue to hold down or force down the stern of the yacht.

    Both the Sea Brake and the Jordan Series Drogue work in a very similar fashion.
    Having time is unavoidable.

  8. #108
    VO5 is offline Registered User
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    [QUOTE=webcraft;3155478]He he . . .

    JSD is usually deployed with a length of chain or other weight at the end. Nylon line plus the fact that the cones are not rigid means that the drag is not constant and is dynamically varied, so once again Shampoo Man is havering.

    JSD keeps the boat's stern dead to wind - no record anywhere in the literature of the 'knocking off' shampoo man froths about.

    The idea that a hundred metres or so of drogue - no matter what it is composed of - could drag along the bottom shows a complete lack of understanding of the physical forces involved IMO. While V05 may have some genuine heavy weather experience his ramblings suggest that he has perhaps survived them more by blind luck than by posessing any grasp of the forces involved.

    Unbeileveable stamina though - 'head and shoulders' above the rest of us, most of whom have long ago lost the will to live while reading this. I promise not to bump it back up . . . .

    Webcraft out . . . .

    @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@

    The key to your entire hypothesis is highlighted in RED (bold), in your reply above, showing you have "an opinion", that's all.

    This shows you have very little or no practical experience of heavy weather in deep water.

    In deep water serious kit is needed with a weight that is guaranteed to embed properly into troughs of 100 to 180 metres with crests 0f 20, 30 metres.

    Serious kit is not suitable for shallow water despite your persistent arguing.

  9. #109
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    Mr VO5, are you "Albert" http://www.anything-sailing.com/show...ghlight=drogue

    (A very long thread where "Albert" attempts to annoy our transatlantic friends: only to be read as an alternative to "Strictly")

    Albert is asked if he has a commercial interest in "Seabrake", his posts are described as "infomercials", he is repeatedly asked to post photos of his boat.

    Post 219 http://www.anything-sailing.com/show...ghlight=drogue: the discussion about Mr Albert Labos and the Chesapeake Bay rescue provoke a very interesting debate.

  10. #110
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    Thumbs up Is It True That You Can Run But You Cant Hide?

    Quote Originally Posted by Fascadale View Post
    Mr VO5, are you "Albert" http://www.anything-sailing.com/show...ghlight=drogue

    (A very long thread where "Albert" attempts to annoy our transatlantic friends: only to be read as an alternative to "Strictly")

    Albert is asked if he has a commercial interest in "Seabrake", his posts are described as "infomercials", he is repeatedly asked to post photos of his boat.

    Post 219 http://www.anything-sailing.com/show...ghlight=drogue: the discussion about Mr Albert Labos and the Chesapeake Bay rescue provoke a very interesting debate.
    Wow Fascadale, too many similarities in the drogue debates and then Post 219 pulls the mask away. I wonder if its true, if I was a gambling man ......
    Having time is unavoidable.

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