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Hatteras "bulbs" for increased speed & stability

Discussion in 'Hatteras Yacht' started by bray yachts, Jan 25, 2005.

  1. bray yachts, Jan 25, 2005
    #1
    bray yachts

    bray yachts New Member

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    Vancouver, B.C., Canada
    It may be of interest to Hatteras LRC vessels that we have retrofitted bulbs to several sizes with great success. The bulbs give a 10% drop in resistance or 3/4 knot increase in speed and almost 50% reduction in pitching. The owner's of these vessels swear by the results.

    Patrick J. Bray
    Naval Architect
  2. alloyed2sea, Feb 23, 2005
    #2
    alloyed2sea

    alloyed2sea Moderator

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    Alex, VA
    Big Nose

    Does that equate to a 10% improvement in economy?
    At displacement speeds?
    At higher??
  3. AMG, Feb 24, 2005
    #3
    AMG

    AMG YF Moderator

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    A bulb on a Hatteras LRC is probably optimized for speeds below 10 knots, and the speed gain will increase the range and economy at the same rate. In this case 3/4 of a knot. However you can probably lower the RPM and run the same speed as before with a little better economy. Most likely 10% better.

    But the real improvement is the stability you get from less pitching in my opinion.