procedure for an inclining experiment in air

Discussion in 'Stability' started by Graham.gemini, Jan 16, 2013.

  1. Richard Woods
    Joined: Jun 2006
    Posts: 2,210
    Likes: 176, Points: 63, Legacy Rep: 1244
    Location: Back full time in the UK

    Richard Woods Woods Designs

    I have been on the 12217 committee since the early 1990's. From experience I can say that international committees work very very slowly. Fortunately our convenor is not only a very good NA but also a skilled negotiator and always (eventually) manages to get everyone to agree.

    Creating the ISO standards was a mammoth job, not helped by non-boating politicians who insisted on changes. And as it was the first truly comprehensive standard we knew some boats would "fall through the cracks" - like the Cambridge river punt for example.

    The long delay between standards is understandable. It took a few years for people to get used to working with the standard and then to offer their comments. It then took several years to rewrite the relevant changes. Finally (the stage it's at now) it has taken three years for the editors to dot t's and cross i's

    Richard Woods of Woods Designs

    www.sailingcatamarans.com
     
  2. JSL
    Joined: Nov 2012
    Posts: 811
    Likes: 64, Points: 28, Legacy Rep: 41
    Location: Delta BC

    JSL Senior Member

    Having participated in guidance in developing new regs (Canada) I can only imagine what the ISO is like. Those who have not participated may not appreciate the time, work, and dedication involved.
    In our case there was often the frustration of dealing with people who were not familiar with small vessels (under 24m) or came up with some real 'zinger' ideas. One of the most memorable proposals was the requirement that boat ceilings (hull linings) be perforated ( 12mm holes on a 300mm grid) so that if there was ever a fire behind the ceiling, smoke could be detected. When it was explained that these holes would also provide air to the fire and accelerate the situation the idea was dropped. Time wasted!
     
  3. Ad Hoc
    Joined: Oct 2008
    Posts: 7,903
    Likes: 1,796, Points: 113, Legacy Rep: 2488
    Location: Japan

    Ad Hoc Naval Architect

    We've been using perforated ceilings for years. Great at sound absorption. Dampa make an excellent range:
    http://www.dampa.com/marine/products/Tiles/Tiles/colours-surfaces.html

    This is the problem with large committee's. Areas of expertise by one individual is often overlooked, or dismissed by the larger number of 'others', as folly, simply because it is outside their area of expertise. I would suggest the ignorance is on the other foot.
     
  4. TANSL
    Joined: Sep 2011
    Posts: 7,647
    Likes: 806, Points: 123, Legacy Rep: 300
    Location: Spain

    TANSL Senior Member

    Like everyone else, I've had to buy the rules and hoped that at least inform me of the changes that were occurring. This has not happened, even though I sent all my data. But what is worse, in the Spanish version of the standard, there was some mistake and, to my knowledge, the creators / translators thereof have not had time to warn users. Frankly, knowing good and appreciating the immense work that involves creating rules, I think at one point they considered finished some jobs that were not.
    The Dampa ceiling is great and helps slow the spread of fire. Its holes, as far as I know, prevent reflected sound in the metal slats. In rooms with low ceilings reverberation occurs, and can be disturbing. Holes not used for anything else.
     
  5. Graham.gemini
    Joined: Jan 2013
    Posts: 4
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: South Africa

    Graham.gemini naval contemplator

    Hi everybody, Just a follow up, I found this from principles of naval architecture volume 1, which clears everything up and has a nice concise method for the inclining experiment in air. find attached if you are interested. thanks for all the help on this issue! View attachment extract from principles of naval architecture.pdf
     
  6. CDBarry
    Joined: Nov 2002
    Posts: 824
    Likes: 60, Points: 28, Legacy Rep: 354
    Location: Maryland

    CDBarry Senior Member

    SNAME and ASTM are currently working on guidelines and a formal standard for air inclines.

    Not ready for prime time yet, but hopefully soon.
     
  7. Heimfried
    Joined: Apr 2015
    Posts: 553
    Likes: 143, Points: 43, Legacy Rep: 37
    Location: Berlin, Germany

    Heimfried Senior Member

    Remark: the linked document contains a faulty formula. On page 127 in the 1st sentence is written
    x = A + B W1 (W1 + W2)
    correct is x = A + B W1 / (W1 + W2)
     

  8. CDBarry
    Joined: Nov 2002
    Posts: 824
    Likes: 60, Points: 28, Legacy Rep: 354
    Location: Maryland

    CDBarry Senior Member

    Note that SNAME has just published T&R Bulletin 9-1, as a guideline for air inclines. See the post "Back against the wall".
     
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.