Subject: Re: HarryCat
From: Mike Crawford
Date: 4/9/2015, 2:10 PM
To: harryproa@yahoogroups.com.au

Arto,

  I'm going to respond to your question from a pro-proa perspective for the sake of discussion.

  That said, I've been quite tempted by a biplane cat for this tacking issue.  I've got about five miles of tacking out of an inlet to get to open water on most summer days with a sea breeze.  It would be nice to minimize effort on those days where I don't feel like squeezing every extra half-knot out of the boat through constant sail tuning.

  For the Pearson Ensign monohull we're renovating as a family/training boat (positive flotation, self-righting, slow), we're going with a taller than usual rig with a self-tacking jib.  Move the tiller... done.

  For a multi, the equivalent would be an una-rigged tacking boat, either with a single mast or a biplane setup. 

  I completely get why someone would want that, at at one time I was trying to come up with asymmetric hulls for a biplane cat that would allow queen bunks at trailering width.  Perhaps a wider port cabin slightly forward and a wider starboard cabin slightly aft, fitting together like a puzzle.  But everything I drew looked awful, and balancing out the weight became difficult.  The proa is just a much more elegant solution.

---

Pro-Catamaran:

    - There's one forward end.  That's handy for autopilots and for balancing the COE against the CLR.

    - Ease of short-tacking in good weather.


Pro-Proa

    - Most of sailing loads are in a single hull, lowering weight, complexity, and cost.

    - Rig is always downwind unless you're backwinding on an ultra-light wind day, so it's easier to observe and tune when there's weather.

    - Shunting will always work, even when ghosting by, or when hit with gales.

    - Ability to stop and/or reverse to avoid a collision, stay off a lee shore, wait out a tight situation when pinched by other boats, or pick up a MOB.

    - Ability to go to neutral and stay put, regardless of the weather (biplane cat only sort of does this because going into reverse is undesirable).

    - Only two foils in the water for less drag.

    - Liftable foils that can vary depth for shallow water or big storms.

    - Foils that will kick up without damage to the boat.

    - Longer waterline and higher righting moment for a given weight and cost.

    - The possibility of righting after a capsize.

    - The possibility of putting a multi with two queen-sized cabins on a trailer (12' wide load limit) and skipping yard storage fees.

---

  For me, one big reason to go with the proa is that I want queen-sized bunks on something that can be easily folded/dismounted and fit into the 12'-wide trailering wide load limit.  That's just not going to happen on a boat with symmetric hulls.

  The Cruiser 60 is beautiful, but it would cost $5,000/year to store on the hard where I live, and that won't fit into our plans.

  But that's just one reason.  I mention it here because it could be significant in the proa-vs-cat debate.

  In truth, all the reasons above are what have convinced me.  Paying so little, for a boat that is simultaneously both fast and safe, is just downright strange.  But cost aside, I can't imagine going to sea on any other multihull at this point.  A few years ago I had options to get a Corsair, then a Dragonfly, but then came to my senses when I thought about doing more than daysailing with them.

  As for short-tacking, the proa might not be as bad as we fear.

  Reasoning:

    - Shunting is going to be easier, more reliable, and potentially faster on big wind days (no panicking or getting blown backwards when stuffing a tack), and light wind days (no worries about getting caught in irons or not coming about as you drift towards a lee shore).  Both of these situations can be problems on a big multi that doesn't turn like a small mono.

    - Shunting may be as fast, or faster, on average (see Rob's post from early this morning).

    - You could potentially add enough rocker to the lee hull to make tacking reliable in moderate winds, similar to what the catamaran would need.  Of course, you'd then pitch more, and the boat would track less reliably on its own...

---

  While I'm sold on the proa concept, my confusion comes in the form of a tall single rig or a shorter schooner rig. 

  The tall rig would be great, with minimal effort for shunting and lots of area up high for light wind days. 

  However, if I ever want to stand a chance of having a ridiculously high Bruce number while still fitting under ICW bridges, I'd probably have to go with the schooner.  That would also provide other benefits, such as a greater ability to right the boat after a knockdown, the ability to steer with sails if both rudders go, and so forth.  But then shunting would take longer. 

  I just don't know.

        - Mike


P.S.  The Tek 35 and Tek 50 are two of my all-time favorite designs.  I still have the September page of the 2006 Multihulls Magazine calendar hanging up in my office with a Tek 50 sailing in a harbor.



Arto Hakkarainen ahakkara@yahoo.com [harryproa] wrote on 4/7/2015 10:22 AM:
 
Hi,

I think Rob's designs are great and really revolutionary. However, since my sailing ground includes lots of narrow waterways where effortless and efficient short tacking and short jibing would be huge bonus over shunting I have given a lot of thought to a catamaran that would have the good aspects of harryproas or at least some of them. What do you think of the following? Let's call it HarryCat just to have a name for it.

1) Semi-open bridgedeck design on the principles  of Shuttleworth Eleri http://www.shuttleworthdesign.com/gallery.php?boat=eleri or TEK 35 http://www.shuttleworthdesign.com/gallery.php?boat=tek35 or Grainger Flying Fish http://www.graingerdesigns.net/yachts/flying-fish-11/ with most of the accommodation in the hulls and with only one or two small deck house that you can see over without climbing anywhere. I don't like the weight, windage and looks of those big deck houses.

2) Cost efficient building with panels, preferably with flat panels like KSS or Schionning Arrow series http://www.schionningdesigns.com.au/arrow-series in order to prevent the budget to break the ceiling. Pre-cut flat panels like Schionning Arrow sound like efficient way of building.  

3) Long waterline and not too much accommodation to keep weight and cost in control. Three double/twin cabins would be optimal with head in both hulls and decent sized shower in one hull. Functional galley and comfortable saloon are high on wish list. 

4) Free standing mast on each hull. Benefits of free standing masts are well known to people in this group. Dividing the  sail are ain two smaller sections makes handling easier.

I have also ideas on motoring, down wind kite options etc. but those can be figured later. Please let me know what you think?

Arto
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Posted by: Arto Hakkarainen <ahakkara@yahoo.com>
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