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Kevin McCready

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Posts posted by Kevin McCready

  1. hopeless poter uleSafety at Sea Triple Series
    Briefing 7th July
    Race 1, 9th July 2016
    Race 2, 6th August 2016
    Race 3, 3rd September 2016
    Prize Giving 23rd September 2016

    Round North Island 2 Handed
    Start 25th Feb 2017

    Round New Zealand Race
    2018 (Date TBA)
  2. The wikipedia article is wrong but well worth a read for its historical and technical info. eg there was sufficient evidence to conclude that 66-foot high waves can be experienced in the 25-year lifetime of oceangoing vessels, and that 98-foot high waves are less likely, but not out of the question.

    Seems that 2 or 3 mins warning which might be possible with the MIT algorithm might be enough to evacuate a ship crew into a survival pod which may need to withstand a hydrostatic pressure of 5,650 kN/m2 (576,100 kgf/m2 or 576.1 Mt/m2 (metric tonnes per square metre). Putting my safety hat on .... what does this mean for yachtie life raft design?

  3. Thought I'd look at the Altex AYB No.5 Antifouling NZ Safety Sheet. It didn't define TWA or STEL or TEEL but did tell me that mice who got too much exposure "produced signs of marked central nervous system (CNS) depression, including prostration after 2 hours, narcosis after 3 hours and some deaths". So if I see anyone lying down on the job ....

     

    Then again, from the Australian Safety Sheet - "Some thiocarbamates are structurally similar to disulfiram and may cause the characteristically unpleasant alcohol type reactions lasting for several hours"

     

    Altex ABY No. 5 Antifoul Composition
    copper(I) oxide    40 - 50%
    zinc oxide         10 - 20%
    n-butanol          10 - 20%
    xylene             10 - 20%
    rosin-colophony    1 - 10%
    thiram             1 - 10%

    etc

     

    For Altex No 5 you can leave it out of the water for as long as you like (Phew, one less thing to worry about)

    Dry Times (75 μm DFT / 25°C / 50% RH):
    To Recoat - Minimum 4 hours
    - Maximum Not critical
    To Launch - Minimum 8 hours
    - Maximum  Not critical

     

    But seriously, chewing gum on the water blasting has got me thinking. The info sheet says "With the correct preparation it can be applied over existing copper based antifouling". Preparation for a repaint is,

     

    "High pressure water clean (5,000 – 10,000 psi / 330 –
    660 bar) to remove all marine growth, hydrolysed antifouling, salts,
    loose paint and any other foreign matter."

     

    "OR: Low pressure water clean (3,000 psi / 200 bar minimum) to
    remove all marine growth, hydrolysed antifouling, salts, loose paint
    and any other foreign matter.
    AND - Wet sand the surface with 80 grit sandpaper to ensure total
    removal of any remaining contaminants, including residual
    hydrolysed antifouling and slime. Rinse thoroughly."

     

    "The cleaned surface, once dry should be free of any powdered
    antifouling residues and should be inspected for defects in the film.
    Existing anti-fouling must be secure and intact, and not excessively
    overbuilt."

     

    "Repairs to the coating system should be completed before the
    application of any subsequent coat of antifouling. To ensure good
    adhesion, any exposed primers / undercoats should be thoroughly
    sanded (p80 grit), dedusted & coated with the appropriate primer
    before application of any antifouling."

     

    "Thorough wet sanding is recommended at the waterline, as the wet
    / dry cycle and UV exposure can cause premature failure if brittle or
    crazy cracked coatings remain." So that is good info re my earlier question about getting marine growth up higher up the sides of Storm Fantasy now that it's in Okahu Bay.

  4. Matt, NZ Territoy covers South Pole to up near Tonga. It's horses for courses. RCC decides, depending on location of epirb, who to contact. They work as a team so while one phones the EPIRB owner's registered contacts, another team member will be liasing with police on a no surprises basis and with Maritime Radio and or coastguard. But RCC will coordinate the response. In the Hauraki Gulf for example RCC would also contact Maritime Radio and helicopter team (they might take a while to become airborne but they have 406 trackers on board).

     

    So I'm inclined to trust, especially given the Channel 16 traffic I hear in the Gulf that the word would be out on the radio before a helicopter launch or boat launch.

  5. Maritime NZ website awaiting update currently says:

     

    "RCCNZ usually receives alerts from distress beacons within minutes. However, depending on the type of beacon you're carrying, it can take two hours or longer for satellites to pinpoint your location."  http://www.maritimenz.govt.nz/Recreational-Boating/Communications-equipment/EPIRBs.asp#Why_is_the_response_not_always_immediate

     

    This advice is very general worst case scenario and applies to land and sea.

     

    The situation on sea is better because signals are picked up easier (no terrain and vegetation problems).

     

    Maritime NZ are working on their website to update with more specific info. Here is what I was told a minute ago by a friendly chap in RCCNS:

     

    1. Turn on EPIRB - 50 seconds to acquire satellite pinpoint fix IF you have a GPS enabled EPIRB.

    2. 50 seconds to beam your fix and EPIRB number to geostationary satellite.

    3. Info goes instantly to rescue centre in Australia and then to NZ

    4. IF for any reason the geostationary satellite link doesn't work, THEN it might take (depending on orbit position) up to a couple of hours for orbiting satellites to pick up your signal.

     

    So, since I have a GPS enabled EPIRB and I file trip reports, I think Channel 16 would be able to broadcast my pinpointed position within 10 minutes, probably after trying to raise me on the radio or cellphone.

     

    So I'm going to rest easy with my neat little rescueME PLB1 (not much bigger than a matchbox).

  6. I use dual or tri-watch depending on VHF in use and it's always on unless I need sleep.

     

    I have a small EPIRB folded into my life-jacket. I trust that if I go overboard my GPS position would be known within minutes??

     

    I also use paper charts for everywhere I go. It's a skill we should all have and maintain.

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