Anchoring: Easy riding small power boat?

Discussion in 'Stability' started by BWD, Sep 9, 2009.

  1. BWD
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    BWD Senior Member

    In light of the recent weather seen in the picture below, here's a little subject I have been meditating on.

    What small powerboat would most happily ride at anchor in the conditions shown below: 15-25 knot onshore wind, small steep waves (0.75-1.5 foot, ~3.5-4 seconds period), shallow water 3-4 feet deep?

    To the right of the picture is one solution (avoid the problem), a good one but for initial cost, eyesore value of boat lifts, and the penalty of a really strong storm (replace 22 foot boat AND 100 foot dock :mad: ).

    What could most comfortably be left at anchor without too much worry in similar conditions, say steep chop up to 2 ft., and 30 knot winds, overnight or all day, if for some reason the boat can't be put up (i.e. crash boat duty or stupid/lazy owner, balky motor, etc.)....

    There are two possible categories of interest, 12-14 feet to take 25 hp or less and 4 adults, and 17-20 ft to take 90hp or less and 5 or 6 passengers. Most interested in planing outboard types, in spite of the issue of the weight on the stern.

    So if the topic has any interest, what you you think or prefer? Motorwells? Sea skiff? Semi-dory? Something else? Any common plastic boat that rides better than most?

    Thanks for any insights, preferences or peeves you care to mention, in spite of the fact this is sort of an "asking for trouble" situation, as conditions do sometimes deteriorate to a real storm.
     

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  2. marshmat
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    marshmat Senior Member

    I can't think of a single planing hull, outboard engine type in the 12-14' range that I would trust to its own devices in waves like that. A boat this size would be better off getting dragged up on the beach after each use.

    At the larger end of your size range, I suppose a Boston Whaler could probably lie at anchor (a big anchor... or maybe a couple of anchors) in waves like that without getting pounded to bits or swamped. An Allweather could certainly handle that and more, but it is a heavier, displacement hull that only goes eight or nine knots.

    Trusting a small boat to an anchor, against steep chop and a lee shore, certainly strikes me as an "asking for trouble" situation though....
     
  3. mark775

    mark775 Guest

    Less mass and self-bailing. An inflatable is a cheap alternative to a good self-bailing boat. I would try to get the thing in front of something other than rock for the eventuality of it dragging and it won't be a disaster if it drags.
     
  4. BWD
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    BWD Senior Member

    Thanks, agree with your answers pretty much.

    For years we had a 13ft whaler.
    Storm tides usually made it easy to get the boat up on a mini railway if weather got bad, and with a light 25hp motor it rode pretty well. A hurricane got the railway though, and the whaler died of age. It survived lots of bumpy nights though, on a 5lb danforth, a yard of chain and 1/2" rode.

    Currently we have something not worth mentioning. Thinking another whaler or an inflatable might be next.

    Among whalers, as many probably agree (?) the 13 footers seem the best, though they're tiny.

    The 17' "montauk" whalers may be ok, but not confidence inspiring because they're heavy and need a heavy motor that makes them pitch and slam at anchor in a blow.

    In between sizes and others that are like "stretched" 13ft whalers seem to like to take most waves over the bow -unacceptable.

    It seems the best features are self bailing and light weight (inc. engine).

    I wonder if having a little more pointy bow might be good though. Certainly don't want to "sail" away and break lose the anchor, but the square bow of a whaler, garvey or carolina skiff does not seem good either, once it starts pitching.
     
  5. Gilbert
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    Gilbert Senior Member

    It is hard to beat a flat bottomed skiff for a beach boat.
    What is wrong with the 14 to 17 foot range?
    You can use a lighter motor for flat bottom skiffs.
    You will want it self bailing for the rain.
    They will ride out anything any other boat will.
    But most any boat will survive if all the elements of the anchoring system is up to snuff.
     
  6. BWD
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    BWD Senior Member

    Maybe will have to go flat next time then.

    I focused on the 2 size ranges ebcause I think there are more likely satisfactory boats in those sizes than in the 14-17ft range, although I am sure there are exceptions to the generalization.
    There are a lot of boats 14-16 or so that seem to be just extend-a-mold versions of smaller ones, without enough freeboard and bad weight distribution, as they are narrow but heavy enough to need a bigger motor.

    Some of these boats will scoop water over the bow from 1 foot chops even when drifting, and powering or anchored can scoop enough green water to overwhelm self bailing in conditions that are really pretty mild.

    So, flat and pointy or flat and bluff?
    Any particular favorites?
    Just askin'
     
  7. Willallison
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    Willallison Senior Member

    Yikes... well 1st instinct is to suggest a trailer boat... on its trailer....;)
    Otherwise a wavepiercing, self-righting monohull that is either completely watertight or VERY proficient at self bailing. As it happens, I'm working on something that'd just about fit the bill, but that's beside the point.
    Problem is that if you have something designed to ride over the waves, it'll spend its entire life trying pull itself apart & ripping its mooring out. Allow it to slice thru the waves however, and both problems are solved.
    I'd still go for the trailer boat myself though...
     
  8. Gilbert
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    Gilbert Senior Member

    My experience with outboard powered flat bottomed boats has all been with pointy bows, so I am not sure which choice might be best for this. Pointy would be good.
    I will attach an article I wrote about thirty years ago about these types of boats.
     

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    Last edited: Sep 14, 2009
  9. BWD
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    BWD Senior Member

    Thanks.
    Think I have seen that article before. I saved it for the offsets. I'd like to model that dory type to compare to the flat bottom skiffs here on the other side of the country, which often are a bit narrower up front. Have a question about the reference to the chine catching or tripping: ever consider easing it forward to mitigate this? I am sure it would be sacrilege to the dory fashion police, but had to ask...

    Re: the boat "on the trailer" yes that is a nice way to avoid the risks of anchoring, but part of the "mission" is to have a boat in the water to use as a rescue for kids in dinghies or anyone else who needs a little help.... It would be nice to get the railway rebuilt eventually, though, that was a very nice thing to have.
     
  10. Willallison
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    Willallison Senior Member

    In that case - particularly if it's going to be used as a rescue boat - I'd think about an inflatable that's kept on the beach and dragged / carried into the water when needed. If it's just a one man operation, then add those flip-down wheels to the transom to make launching easier.
    Kids, waves and hard boats don't mix well....
     
  11. rwatson
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    rwatson Senior Member

    Just to add another example fo a light boat riding out a storm that sank other bigger boats, have a look at

    http://macgregorsailors.com/phpBB/viewtopic.php?f=9&t=14272

    The smaller boats are a lot less mass dragging on an anchor, and can ride up the waves rather than through them in many cases.
     

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  12. Fanie
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    Fanie Fanie

    Such a small boat - take it out the water.
     
  13. hoytedow
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    hoytedow Carbon Based Life Form

    Agreed. Why gamble with it?
    By the way, Fanie, we are enjoying S. African oranges now while Florida oranges are out of season. Do you get Florida oranges in S. Africa when yours are out of season?
     
  14. Fanie
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    Fanie Fanie

    :D Dunno. I'm not big on oranges
     

  15. zamgod
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    zamgod Junior Member

    17ft Wilson Flyer Pilot Anchorage

    Hi,
    I've just joined the forum.
    I had to show you my 17ft Wilson Flyer Pilot at anchor in the bay during a force 8/9 gale. She is powered by a 50hp Evinrude. I must admit I was a little bit scared that she would break her moorings.....but she never budged!
    An automatic bilge pump kept her dry during the gale, it has since given up and failed.

    Regards,

    zamgod
    fae bonnie Scotland
     

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