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by Rob Denny

Harry is a 12m (40') loa, 6m (20') wide Pacific proa with 35 sq m (376 q') of sail.   Harry is a basic weekender for 4, or an extended coastal cruiser for a couple.  The original idea was to get my wife Sue back into sailing, while providing me with a boat capable of winning races.  Sue dislikes heeling, pitching, getting wet, pulling on ropes, winding winches and having to move around all the time.  Her idea of sailing is sitting comfortably, watching the world go by while she sips Chardonnay and chats to her friends.   Harry fills these requirements admirably.

It has long been observed that the main requirements of any boat are space, speed and low cost, and that while any two of these are possible in a particular boat, all three are not.  However, if you are prepared to sail a boat which looks different, and requires a slightly different tacking technique, perhaps it can be done.

Harry is a Pacific proa with a difference.  All the accommodation is in the weather hull, always.  To the best of my knowledge this has never been done before, as according to popular wisdom, a proa with a balanced rig and most of it's weight to windward will not shunt successfully.   Five years experimenting with various possibilities has resulted in a boat which not only shunts, but shunts very well.   Not quite as quickly as a mono tacks, but considerably quicker and far easier than a lot of multis.   Shunting is peculiar to proas.  Because the same hull is always to windward, proas don't tack.  They are stopped, the air and water foils reversed and they take off in the opposite direction, with stern and bow having changed roles. 

One of the prototypes for Harry was "U" which can be viewed on Michael Schacht's Proa File.   This also contains some of the thinking behind Harry and more details on shunting.

Sailing Harry singlehanded takes less effort than any other boat I have ever sailed.  Harry  points high, sails fast and is very responsive: in many ways more resposive than conventional monos and multis. 

Harry has the following attributes:

There are 2 hulls.  The leeward one handles the sailing function, is 12m (40') long, very narrow and contains the rig and rudders.  The windward hull (the Chardonnay side), is 7m (23') long and contains the accommodation, consisting of 2 large double berths cantilevered off the inboard side of the hull, standing headroom, galley and seperate toilet and shower.   This layout not only puts most of the weight in the right place (to windward), it means that the non sailing crew (wife, kids, guests) do not have to be involved with the sailing.  They can sit or lie on either the  contoured bench seats or the trampoline, well clear of the sailing action, and the spray.  No changing sides when the boat tacks, no need to avoid travellers, winches and sheets and no getting in the way of the sailors. 

The weather hull also has far fewer structural requirements. Without a cockpit, mast, rudder, centreboard or deck fittings requiring bulkheads, stringers and frames for support there is much more space available and many more options for how to use it.   The built in bunks and open spaces make fitting the galley, benches etc much easier, lighter and quicker than on conventional boats.

The comfort is not just for the non sailors.  Harry has an EasyRig.  A balanced sloop rig, on a self supporting carbon mast.  This means no winches, travellers, tracks, turning blocks or highly stressed sheets.  The main sheet is a simple, lightly loaded 2:1 purchase,  no other sheets are required.   To tack or gybe, the sheet is released, the new sheet trimmed, the rudders reverse almost automatically and off you go.  Marginally slower than tacking,  but almost effortless, and a lot more controllable, particularly at low speed or in crowded waterways.   Apart from the scenery going in the opposite direction, the passengers are hardly aware of the change.  The self supporting mast is designed to flex and reduce power at a given wind speed.  This automatic depowering delays the need for reefing and makes the boat a lot safer in gusty conditions.

Speed:  Harry has raced a couple of times, but due to teething problem is yet to excel..  Harry's vital statistics imply that it is be no slouch.  Weight 650 kgs (1,430 lb), sail area 40 sq m (430 sq'), loa 12 m (40') and boa 7m (23').  Harry is one third the weight of a typical lightweight racing 40 foot cat.  Consequently it is very easily driven, (7 knots with a 5 hp outboard) so a small sail area is sufficient for cruising. Top speed sailing o far is 13 knots in 12-15 knots of breeze.  This was according to a borrowed GPS.  Hrry has certainly gone faster, but not verifiably so.   The light weight is not at the expense of strength.  Pacific proas are far less stressed than conventional multis.  On Harry the stress is reduced even further by placing all the rig, beam and steering loads within 2.5m of the middle of the leeward hull.   

Light though Harry is, a racing version would weigh about half as much, and with optional water ballast could carry twice the sail area.

Harry is very stable, theoretically not flying a hull in cruising mode until the apparent breeze reaches 25 knots.

Harry is also very safe.  With the rig in the leeward hull, none of the sails' heeling force is trying to bury the leeward bow, the most common cause of multihull upsets.    

When it does fly a hull, the boat rotates around the base of the mast.  Consequently it has a very smooth stability curve which is still positive at very high (over 75*, depending on crew location) angles of heel.  If it was to capsize, the buoyant mast and boom should stop it going past 90*, and should also act as a sea anchor, enabling the hulls to blow downwind, at which time the wind should flip the boat back upright.  Lots of
"shoulds" in the above as it has yet to be tested, although it worked on the prototype.  It will be tested on Harry in the near future.

Harry is built of timber, epoxy and marine ply, fibreglassed inside and out.  It has a carbon mast and rudder stocks.  It is an ongoing test bed for various ideas and is continously being altered so although it is reasonably well built, the finish is pretty rough. 

Harry is light and cheap because everything has been kept simple.  It is also highly effective.

Some examples:
1) There is no metal in the boat apart from the eyelets in the sails.  Metal causes stress concentrations, is heavy and expensive.  Fibreglass tow in epoxy requires a bit more thought at the design stage, but spreads the load much better, does not require holes in the structure, is easy to apply and cheap.  
2) The building technique is incredibly quick, a combination of the best of strip planking and sheet plywood techniques, made possible by Flexiply, a plywood with 95% of the laminate in the lengthwise direction.  Each hull needs two building frames/bulkheads, and a couple of pieces of 4x2.  Very simple, self aligning and difficult to mess up.  No special tools are required and the finished hulls are not only relatively small in surface area,  they are inherently fair;  sanding, fairing and torture boarding are limited.  Harry was built single handed in a 6m x 3m (20' x 10') space and assembled at the waters edge.  As well as the hulls, beams and original wing mast, even the steering wheel is built of Flexiply.  A competent amateur should be able to build a Harry in 250 hours.
3) The EasyRig.   The name says it all.  It is also low cost compared to conventional rigs and all their associated paraphernalia and has far lower ongoing maintenance costs.
4) Rudders.  Harry has two large rudders, which rotate through 360*.  These not only steer exceptionally well, but remove the need for centreboards.  They can be lifted for off the wind sailing, or when shallow draft is required.  They will kick up in the event of a collision.  The rudders are one of the reasons why Harry works so well.  Even at low speeds, they operate efficiently, so shunting and maneuvering in tight situations are very simple.  Carbon shafts ensure adequate strength.
5) Apart from rope (6 and 8mm spectra), the trampoline and a couple of sheaves and cleats, there is no chandlery on the boat at the sailing stage.  Far cheaper, and in  many cases easier, to build the required fittings in situ.
6) The cantilevered bunks effectively reduce the length of the beams, further reducing loads which are already much lower than those on cats and tris.

Harry will not be everyone's cup of tea.  Sailors are notoriously conservative people, and many of them buy boats for reasons other than speed, comfort and low cost.  However, for those who do want these attributes, and who aren't afraid of being different, Harry kits are available for $AUS25,000 ($US14,500) plus tax and freight.   The kit boat is a Harry Mark 2.  The differences between Harry  (photos) and Harry Mk 2 (drawings) are that Mk 2 has a much more spacious weather hull, a single cantilevered beam, a more rounded lee hull, smaller boom and stiffer mast.  Mk 2 is professionally engineered, considerably more robust, easier to build and a little lighter than Harry.  The first Harry Mk 2 is currently under construction and should be sailing in August.  All going well, it will be sailed to New Zealand (1,600 miles), then to Sydney for this years Sydney Hobart.

Kits will include everything needed to build a boat and go sailing.  That is, all the materials, Gary Martin sails, all deck gear and rigging, marine paint and long life antifouling,  professionally built one piece carbon mast and rudder shafts ,  detailed plans and building instructions and as much email, mail or phone advice as is required.     Finishing it off ready for weekend use is a matter of personal choice, but a minimum may be:  bunk mattress,  outboard and bracket (or sculling oar), cooker, toilet, anchor, flares, fire extinguisher and lifejackets.

Tools required are electric screwdriver, jigsaw/sabresaw, 4" grinder, orbital sander, string line, level, straight edge and tape measure. A router is also handy for rounding edges.

Professionally built Harry Mk 2s are also available.

Study prints including ongoing updates, are available for $AUS30 ($US19) each. 

A trailable version of Harry is currently on the drawing board.

Harry lives in Brisbane,  Australia.  Anyone wanting a test sail is welcome.

Rob Denney
8 Carrington St, Paddington 4064, Australia
ph 61) 7 3217 6500

About the designer:

Rob is one of the most experienced offshore multihull sailors in Australia.  He has competed in 7 Sydney Hobarts, 7 Brisbane Gladstones, has crossed the Tasman half a dozen times, plus 2 Trans Atlantics and extensive cruising in the Pacific and the Med.

Previous designs include a windmill powered 9m (30') cat, an 11m (35') ultra simple racing cat, a 12m (40') cat with hulls free to pitch independantly and 2 smaller prototypes of Harry.

He has worked as a boatbuilder, imported and sold boatbuilding materials and built carbon spars and components. 

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