<<My single question with regard to this is how relevant is it in real life sailing... when one is not pushing the boat to it's limits as you might in racing?>>

  If you're daysailing in nice weather with stable wind predicted for the day, the real world is kind.

  Or, if you have a low SA/D and a high righting moment, then there are probably few worries.

  But sometimes you can't predict when wind shifts collide with misjudgements.

  Back in 2004 there was an early November day I took the cat out, with wind mild enough to where I didn't even bother changing sides when tacking.  Seven knots perhaps? 

  Then the wind had a big gust that lifted the ww hull out of the water, wind speed dropped almost back to what it was, and then doubled its original strength in a few seconds and stayed there.  No problem, I thought, as the ww hull kept rising, sliding me back against the leeward cabin: just dump the mainsheet.  But it was locked tight, and the position I was in didn't give me enough leverage to pull it down out of the cam cleat.  And then as the hull lifted farther, the mast raised higher above the water, and the windage of the deck and tramp came into play, and the heel accelerated.  Somehow, in painfully slow motion, I was able to climb up the deck, which at that point was past 45 degrees, grab that sheet, and yank it free.  And the boat slowly lowered back down.  What a relief.

  But it was still hurtling towards a shoal and I couldn't just stop the boat, so I had to get back to sailing and tack a few times, which had its own level of scariness given I hadn't reefed, and couldn't really reef in that level of wind, on that boat, by myself, because I had no way of keeping the boat into the wind while I tended the sails.  And then I had to wrestle those beasts to the deck, trying not to get blown overboard, while periodically hopping back to the tiller and pointing back into the wind.

  The worst case would have been a ugly November day in Maine waters, alone, with no one to help me.  I was in protected waters and could have swam to shore, so it wasn't life-threatening, but it would have been a very expensive error.  I probably would have lost the mast, a well as all my electronics and some of my equipment.  Maybe the motor, too.

  That was my first season with the boat.  Now I have a 12:1 mainsheet instead of the 8:1 it had, I have a working 8' traveler that's also easy to dump, I have rope that's easier to grip, and I won't dare recline to leeward with my feet up unless I have the sheet uncleated and/or we're just ghosting along.  I also have a furling headsail and a stackpack/lazy jacks for the main, both of which make singlehanding a lot safer.  And the autopilot I added is invaluable in keeping the boat motoring into the wind while I tend the sails.

  I'll admit that I wasn't making the best choices, but at that point I'd never experienced that situation.  The boat had never lifted a hull more than an inch or two and had been surprisingly stable and fast.  Until it wasn't.

  Given that I want to sail an even higher performance boat, and go somewhere with it, the "what happens if the wind gets huge really quickly" question is a significant one. 

  Scary is fun if you're planning for it that day, and have the skills and crew to manage it.  But I'm not looking for that particular brand of scary if I'm out of sight of land with my family.

---

  How different that day would have been if:

    - The boat lost heeling moment instead of gained it as the hull lifted free.

    - The boat had a higher righting moment because of its design.

    - The masts were flexible enough to dump a lot of that initial gust.

    - The mainsheet were lightly loaded with the boom taking the leech tension (so I could uncleat it).

    - I could have calmly shunted instead of going through the drama of feeling the wind slam into the boat during the tack, trying to man the jib, main, and tiller at the same time.  (I had to tack a number of times before I got to a place where I could drop the sails).

    - The boat had been a schooner rig with sealed masts that technically could have survived a knockdown.

    - I could have depowered and collected my thoughts while the boat happily sat there, instead of scrambling around trying to get two sails down singlehanded without losing the boat or getting blow off deck. 

 
  You could say that none of this is an issue if you're cruising around and not looking for extreme performance.

  On the other hand, that's when the safety margin becomes more important because the stakes are higher.

  Even if we're cruising and heavily-laden, most of us want enough sail area to move when there's just enough breeze to ruffle a penant, even if our goal is just to make four knots. 

  And then that sail area goes from being too little to too much when the wind takes a surprising turn.  Perhaps at night, or while you're below decks visiting the head, or one of the cousins is at the helm.  Maybe the sail area is a big aero or una rig, two tall schooner masts, or maybe a conservative bermuda rig with a big A-sail out front -- you can fly a lot of sail with a relatively short mast if you want to.

  If I'm going so spend $100,000 on a boat, and take it out of sight of land with non-expert crew, I want to eliminate as many worst-case scenarios as I can.

  Lots of folks don't care, and are simply willing to accept a given risk because it has always been there.  Like being in a 40,000 pound monohull that will sink to the bottom of the sea if its keel bolts fail or a seacock goes bad.  To me, that's uncool.  I'd rather have a very wet boat, and a miserable day, on /top/ of the water, than risk losing the whole boat.  So any boat in in our collection has to have positive flotation, and not with inflatable float bags.

  I've always thought this way, but after years of getting scared on the catamaran (some fun-scary, and some not), I feel more passionately about it than I did before. 

  I still love the boat, and I will admit that I sometimes enjoy sailing something that demands attention and skill. 

  But man, it would be awesome to have something even faster, but also far safer and more forgiving.

  And if I had my family on board, the added peace of mind would be invaluable.

        - Mike

 

Rick:

    The heeling aspect was discussed in an earlier thread........My single question with regard to this is how relevant is it in real life sailing... when one is not pushing the boat to it's limits as you might in racing???  It's one of the ingenious aspects of Rob's designs.   A lot of details had to come together in the HP that make it very very different from other proas so that it would be a stable safe ocean going platform that can complete with other blue water boats and acquit itself well, even excel.   I'm beginning to understand the value of the slenderness ratio.... I forget the proper term.

    It has seemed to me since I "discovered" the HPs that one of the split junk rigs would be a pretty ideal rig on an HP, not requiring the extremely heavy boom and pivoting mast.   The aerojunk by Paul McKay that flies a flat sail inside of a batten cage which imposes camber on the sail by virtue of it's shape and the lines connecting the sail to the cage... which can be adjusted fairly easily to change camber, is my favorite rig.   It is rugged, and it is simple, and eliminates things like a track and cars, and expensive commercially made sails with huge amounts of tension across the entire sail.   It would be particularly appropriate where two masts are used.

    The HP really falls closer to a trimaran than a catamaran in terms of payload and accommodations per foot LOA.   Those are my most heavily weighted criteria after safety.

                                                                                    H.W.

On 2/28/19 7:49 PM, Rick Willoughby rickwill@bigpond.net.au [harryproa] wrote:

 

One feature of an HP not yet mentioned on this thread, but previously noted, is the reduction in heeling moment when the lw is pressed. This is unlike other multihulls where the base of the rig lifts when the mast is in the middle of the two hulls and the lw hull is loaded and the ww hull unloaded. 

An HP performs reasonably well in light wind.  Neither hull makes substantial wave drag at low speed making hull cleanliness the key factor in light wind performance.  In the wind range where the shorter, heavier ww hull starts to make waves it is already reducing displacement and the displacement of the longer slender lw hull is increasing.  The lw hull has low wave drag throughout its range of displacement and speed range.

A distinct benefit of a HP over a tri is the clear deck space..  At times the trailing end of the boom on the Aerorig can be difficult to get at if some thing near the main clew needs attention.  However this would not be so much of an issue with the schooner rig where the sails can be worked independently.

The bi-directional hull is not the most efficient form for planing.  So any boat with the power-to-weight to plane is going to be more efficient if unidirectional.  The amas of modern tris are typically long slender planning hulls with near full width transom and little rocker aft.   Even the maxi monos are now designed as planing hulls with wet transoms at rest.

For berthing and trailering the HP takes up less space than a tri of similar accommodation and performance.  

In my view a tri or cat makes more sense as a foiling platform than a HP.  However that may be because I am yet to see a foiling HP.

Rick

On 1 Mar 2019, at 9:05 am, Björn bjornmail@gmail.com [harryproa] <harryproa@yahoogroups.com.au> wrote:

I like all the aspects of the Harryproa except one thing - that it has two hulls in the water in light airs. (Maybe also that it has to stop to gybe.)

Why not instead build a trimaran with unstayed rig(s), one centerboard and one rudder?

With basically just one hull in the water in light airs, it will always have less wetted surface than two hulls, unless it's way heavier than the HP. It will have the same amount of appendages(foils in the water) as the hp. It will have a rig which is as easy to control.

From my point of view, it's only in two situations a multihull feels slow:

-When the wind is really light

-If it glides a lot sideways (leeway) when sailing into the wind.

This is from sailing Hobie 14 and Dart 18 for a couple of summers. (Both are without center boards.)

I suspect that a well designed trimaran might not be that much heavier than a HP. Maybe the design will have to have short floats attached with a single beam to accomplish that. And then maybe small lifting foils on the floats, which starts lifting when the float gets loaded enough to have higher drag than the foils.

Maybe you can tell that I'm a fan of the extremely cool boats made by Gary Baigent, which I've seen on boatdesign.com and sailinganarchy.com =)

(And the French hydrofoils which is part of his inspiration. =))

/Björn