The Wylie Cat masts do rotate -- one of their selling points is that this allows you to depower that huge sail with a single two-part mainsheet.

  Yes, a lot of stress on the snotter, but not a problem if designed for.

  However, those big low-aspect sails have a lot of area behind the mast.  That works well on a unidirectional boat where you can put the mast up front catboat-style, but might also be a bit far aft for a bidirectional boat.

  I'd probably lean towards masts with booms and outhauls.  Still two strings to pull, with a lightly loaded mainsheet, but the sail design would be simpler without the lower diagonal section having to support that wishbone load, and you could protect the entire sail from UV light with a simple zip-up cover extending from the sides of the pocket/park-avenue boom.

  That said, the Wylie design is brilliantly simple.  It would be interesting to see the cost difference between the two designs.

        - Mike

 

No problem with 3 masts, if the boat is big enough.  Not sure how big is big enough, would depend on the size/weight of the sails and athleticism of the crew.  The mizzen depowers automatically.  The load on the aft sheet is small compared to the fore one.  Presumably this applies double to a 3 master.  Lower coe is good in a breeze, bad in the light. 

Can the Wylie cat rigs mast rotate? Big load on the snotter if so.   If not, you lose a lot of the unstayed rig's versatility, although you probably pick up some efficiency by having the track on the lee side of the mast.   If this could be overcome, then the wishbone rig would be a good option.

rob

On Sat, Aug 3, 2013 at 4:42 AM, DaveC <dave@kiteship.com> wrote:

 

Hi,

In the vein of smaller rig parts, is there any argument for a 3 masted schooner on a Harryproa? I'm thinking about wishbone booms on unstayed carbon spars. Why 3? Lower height of CE, less fore/aft shift of CE, more total sail. You'd take a little hit upwind, but then again, depowering the mizzen helps with sail balance. I bet a single-hander (or real-life husband/wife team) could sail her, from slip to trans-oceanic, in sizes to 75' OA.

I think if I had a Harry, I'd want a wishbone schooner, 2 masts if smallish, 3 if largish. Tom Wylie's big 65' cat ketches, (cat-headed monohulls, not catamarans--unstayed carbon spars) with wishbones on both sails, are pretty darn simple/controllable, given the size of the sails. His main is something like 1500 sf, uses a two part sheet. When he reefs, he has a "basket" built of lazy jack-like bits of line under the boom, just drops the sails into these, then if he wants a reef, sorts it out in the "basket." http://www.wyliecat.com/wishbone_rig/

Dave Culp