Raised Helm Deck for Inlet Surf Running Idea

Discussion in 'Boat Design' started by DouglasEagleson, Mar 9, 2016.

  1. DouglasEagleson
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    DouglasEagleson Junior Member

    I was trying to figure out the issues of running an inlet in a sailboat with surf conditions. I already posted my concern about absolute law in preventing broaching. I would idle through the surf rather than risk the true planning of a displacement hull.

    I remember seeing ocean cruisers at a Miami Marina and noticed the stern davits for dinghies. I was figuring in general and considering the low mass of composites these days a helm station on the davit tops is doable. A small deck with chair and a fancy remote tiller. The idea is to get up out of the cockpit so the helmsman is not disturbed by surf through the cockpit.


    boat schematic of idea

    ******deck on davit top
    bow
    @@@@@@@@@@@@@@@@&&&&dinghy
    @@@@@@@@@@@@@@@@
    @@@@@@@@@@@@@@@@stern


    It would also help in getting a angle on viewage of coral ahead.


    I am also an adamant proponent of pilot houses for all non-daysailers. There are certain low pressure areas that form out of nowhere with no warning. Hideous force 5 lows like the "Perfect Storm" movie version. These are always going to be encountered if you live a sailors life. You will be standing there in utter calm winds wondering what the cloud formation means. Waiting for the wind level to make the retreat to the cabin. The problem is the wind "hits". It can go from zero wind to a suck the people off the deck in one second. Waiting in judgment of hazard on the deck is a deadly error.

    Inlet running using the pilot house is a visibility issue. Sometimes a clear outside view is required for noncontroled inlets. The rear helm station has seat belts of course.
     
  2. gonzo
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    gonzo Senior Member

    A force 5 is a fresh breeze. Simply a nice sailing day.
     
  3. DouglasEagleson
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    DouglasEagleson Junior Member

    Force five is what the lows exhibit in the areas not encountering the central winds. Think of a class of earth sweeping cyclone. They do have a character of having a reduced survivor to warn of the center.

    They are occurring with no professional warning also. Not forecast.
     
  4. PAR
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    PAR Yacht Designer/Builder

    Agreed, maybe you need some more sea time as force 5 winds, are before SCA's are posted and generally considered nice sailing weather. I'm not sure about what you're calling a "hideous force 5", but the perfect storm experienced in the early 90's was mostly force 11 and 12 over the Flemish Cap and nothing remotely similar in any regard to a 19 knot (mean) force 5 afternoon.

    This said, running an inlet takes experience and lots of bravery at times, depending on condisions, the inlet, tides, etc. I've been scared many times running an inlet, but this isn't unusual and a good boat with a skilled skipper can manage, without resorting to anything other than their wits.
     
  5. DouglasEagleson
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    DouglasEagleson Junior Member

    comment reply

    I will reset my story telling I guess. I just remember a force 5 that decimated a racing sailboat fleet off the UK in the 70's. As a kid I read it that way. Like six crew dead and all heavy fin keel damage to all survivor craft.

    I will stop story relating I guess.

    About inlet running. My goal is to use the brain to make running as safe as possible. So my design defends and obviously makes it safer.
    Hanging a upper rear deck over the stern is a cool idea. Free decking.
    A defensive plan calms the concern issue.
     
  6. Mr Efficiency
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    Mr Efficiency Senior Member

    What the ?
     
  7. Schooner Guy
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    Schooner Guy Junior Member

    Are you referring to August 1979 Fastnet Race ? If so you might to read the book FASTNET, FORCE 10
     
  8. SaugatuckWB
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    SaugatuckWB Junior Member

    Do you mean Cat 5, as in hurricanes?
     
  9. PAR
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    PAR Yacht Designer/Builder

    Yeah, I don't get what this guy is talking about either. I have a buddy that survived the '79 Fastnet, in fact without much damage, but not so much for others in the race. There was nothing force 5 about that particular race, other than the start. It quickly went to 6 with force 7 gusts and condisions deteriorated from there.

    Again, running an inlet is more skipper skill than anything else. Placing a raised deck on your boat isn't going to help the boat any, in fact could jeopardize it quite a bit, on certain hull forms. Maybe you can be a bit more specific about what you're thinking instead of generalized, undefendable claims, about monster force 5 storms. Frankly it sounds like you've never been in a healthy gale, let alone what was experienced in that particular Fastnet.
     
  10. gonzo
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    gonzo Senior Member

    The problem with that Fastnet was that inexperienced crews on boats designed for daysailing went offshore. A couple of friends of mine were in that race and were really surprised when they returned and heard the news. They described the conditions as wet with two reefs taken down. No big deal.
     
  11. Harshavardhan
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    Harshavardhan New Member

    Sir(gonzo),
    sorry to post in this thread.I want to know how we will calculate So2 and No2 emmisions in ships. the problem is given below.
    ( A ship has a main engine (17000 kW at 90 rpm, NCR condition) and three auxiliary

    engines (800 kW at 750 rpm, NCR condition). The specific fuel oil consumption (SFOC)

    for the main engine is 175 g/ (kW.h) and for auxiliary engine it is 190 g/ (kW.h). The total

    weighted emission of NO2 from the engine is as follows:

    (a) 17.0 g/ (kW·h) for n (rpm) ≤ 130

    (b) 45.0 x 0.2ng/ (kW·h) for 130 < n (rpm) ≤ 2000

    The sulphur content of the fuel oil used on the ship is 4.5% m/m. The total weighted

    emission of SO2 after combustion is two times the weight of the sulphur in the fuel. To

    maintain ship’s design operating condition, the SFOC of the engine increases by

    0.01%, while the NCR power of the engine increases by 0.005% of its value the

    previous year. The total life span of the ship is 30 years. The main engine and the

    three auxiliary engines work on an average 350 days per year at NCR condition. What

    will be the NO2 and SO2 emission during the lifetime of the vessel?))


    Do we have use Mcr or NCR? and what will happen if we increase NCR?
     
  12. DouglasEagleson
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    DouglasEagleson Junior Member

    a concept.

    I remember the term force 5 not category 5

    Just remember there are storms where the survivorship is so low nobody survives to report the storm behavior.

    It is like a cargoship captain waking up and goes to the steerroom. And it is all empty. No crew. The only distinction is a broken window. Well what happened? A "something" unknowable sucked everybody out the window. But what was the exact weather that did it is unknowable, their dead. Speculation can not be done.

    When I talk of magically appearing low pressure areas. It means just that. No warning.

    I do have a ton of weather experience. And I have helped rewrite rules of flying.
     
  13. gonzo
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    gonzo Senior Member

    We are getting into the realm of sci-fi movies where the outer space zombies abducted the crew through the window. If the windows on a real ship were to break because of a wave, the whole bridge would be swamped. No captain will sleep through that.
     
  14. Skyak
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    Skyak Senior Member

    To your original question -it seems to me the fear in running an inlet comes from waves against tide stacking up and causing a broach in a narrow channel. Even a brief loss of direction can result in a grounding in even worse breakers. An improved view is nice but I would vastly prefer a lifting keel for the surf in.
     

  15. tom28571
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    tom28571 Senior Member

    I also don't understand the OP's affection for a pilothouse on a sailboat or a steering station on a platform high up over stern davits. Both get negative reviews from me. Can't imagine a worse place to be than high up exposed on a point that can be whipped violently in a broach. Sounds like a death wish. In addition to more familiarity with the Beaufort Scale, some time in boats going into a nasty inlet with wind and current opposed would be helpful.
     
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