Monday, September 4, 2017

Double Lug Rigged Shunting Wa'apa

I recently received the following letter from John Lazenby of Washington state:

I thought I'd share what my Wa'apa looks like these days.

I've put a shunting dipping lug schooner rig on it. The sails are pretty well balanced, I think each COE is about 12-18 inches aft of the mast. Each sail has a continuous tack line that goes through two blocks, one ahead and one aft of the mast. Hauling the tack to the new tack point is generally enough to get the yard to dip over to the new side. The sails set beautifully and symmetrically on each tack. The total sail area is 160 square feet. On a recent outing (with mutli-day camping gear aboard) I was able point higher and sail faster than a Welsford Navigator, so the rig does fine working upwind. I couldn't really tell you how close I can sail to the wind, since I generally sail in pretty significant currents. It does seem to point better when the currents are favorable... I haven't come up with a great way of keeping the sails from blocking each other on a run, so it isn't the fastest boat going straight downwind although it does fine. I'm working on extra tack points to move the fore sail more toward the ama. The sails have two reef lines at 25 and 50%. Since I generally do multi-day cruises, I love knowing I can reef and do it early and often.

It started out life with the oceanic lateen shunting rig. A beautiful, fun rig to sail. I decided to try another rig in a powerful afternoon wind on a mountain lake. While shunting in high winds, the sail with both 20 foot spars would kite high into the air, occasionally swooping in to snap off an unsuspecting cleat or body part. At that moment a pair of smaller, reefable sails sounded more manageable. 

The photo shows the boat in full cruising mode. You can just see the inflatable kayak/safety ama on the leeward side. That is a fantastic combination. Anchoring is often more practical than pulling ashore here (Puget Sound) with tide swings that seem to generally be in the 15-20 foot range. So having the kayak as a tender is very convenient.

The main hull is fully decked. Each of the three sections is divided in two with a watertight rigid foam bulkhead. Each compartment has a somewhat watertight hatch. The center section hatches are stored inside their compartments most of the time, but get put in place in force 4 or 5 when the reefs go in.

I have a 30 inch wide trampoline and a park bench for comfort. I sleep on the trampoline and set up a lean-to tarp between the bench back and the masts.. The park bench makes for comfortable sailing in high winds or when I'm not worried about performance. The bench also provides a solid surface for setting up a stove.

I have an asymmetrical triangular cross section ama. The ama has about 1 person worth of buoyancy. It is a single piece, 16 feet long and has two removable hatches to air it out during storage. The leeward side is vertical. I have a foil whose top slides along a rod above the ama. The lift gets transferred to the straight, flat side of the ama. The foil needs to be a couple of feet behind center when working upwind, and can go all the way aft for downwind. The lines that pull it along the rod also release a brake that clamps onto the rod. When the sails are aback, the foil is free to pivot up, so the boat has relatively little lateral resistance aback, which makes me feel like there is less stress on the parts of the boat that weren't really designed for those forces. I have stays on the masts going out to the amas that have been converted to 1/8" dyneema since this photo was taken. They make me feel better about the forces on the masts while working upwind.

Shunting is pretty quick, but  also pretty busy when singlehanding (almost always singlehanding). Release the (continuous) sheets (aft first to get the old bow to start falling off). Release the (continuous) tack lines. Tighten the new forward tack line.  Shift the foil aft. TIghten the new aft tack line. Sheet the aft sail in part way (not all the way, it will stall). Sheet in the forward sail. Generally sheet in the two sails together, keeping the aft sail a little tighter, since you are also trying to swing the bow to windward. With camping gear, and a few days food and water aboard I can shunt about as fast as I can decelerate the boat and accelerate it on the new tack.

I transport the ama and masts on my car top. The rest of the boat gets stacked on an 8 foot utility trailer. I can set up or take down the boat in about 45 minutes for day sailing. It takes 1.5 hours if I need to inflate and attach the kayak and load up all my cruising gear. It often takes longer when I'm talking to people who are interested in the boat. My record is about 2.5 hours when I assembled it at the Port Townsend Pocket Yachters Palooza while talking to many interesting people.

The boat (just the two hulls, actually) is about 5 years old now. Still no name; I'm open to suggestions...

1 comment:

proasail said...

Fantastic my TP03 used a very similar system.
https://youtu.be/eW078PPgJak

http://proasail.blogspot.co.uk/

I was really pleased with the concept but ultimately didn’t really have anywhere suitable to sail it and time to really develop it,