A little on what's actually happening. We are flying along (4.5 to 6 knots) dead down wind and down seas. (Wind directly blowing from the North over our stern and the 1-3 metre swell - old smooth big waves) also come up behind the stern and we rise up, get pushed a little either side and often slide down the front of the wave face with a sweet swisssshhhh... then "Monti" our Monitor Servo-pendulum wind vane corrects our course with regard to the wind pressure on the wind vane paddle.
Monti then pulls or pushes the tiller (fondly known to the rest of the crew as "Tilly") to bring Terrwyn back on course. Monti has a water paddle also which actually powers the tiller control. Very very clever, silent, reliable and zero energy provided by us as electrical or mechanical assist. "Monti" does this via "Tilly" 98% of the time and we correct "Monti" by moving his wind paddle 1-2 inches into the wind every few hours as the wind or seas back or veer every few hours. (Cathy says its a "Look Ma no hands" situation for the rest of the crew since Monti and Tilly have everything well in hand - as it were!). That's how we steer Terrwyn after plotting our position on the chart and determine where we want to go. The wind and sea condition limit where we can go and the changing conditions make it all a dynamic fun project.
Now the power to push Terrwyn (20,000 lbs.) through the ocean obviously comes from the wind. We catch this wind energy by putting out various sails, the sails transmit to energy via the rigging (wires and ropes) to the hull and the hull pushes through the water. Simple.
For example after our first few days " beating' into the SW wind we picked up this amazing Northerly Breeze pushing us along due South exactly where we want to go. So, for the last week or so our 10' 10" wide vessel has presented to the wind nearly 35 feet across of sail. To do this we deploy two spinnaker and whisker poles to the sides to hold out the sails, two twin jibs, head sails in our rig's 37 feet , 20,000 lb. displacement. This is where our work comes in. It often feels like we rowed the darn boat all day after pulling, setting and changing the position of these ropes (lines) to control the poles and the sails. We love this work... and work it is... but it is good work. Like mountaineering rope work, these lines which average 1/2 inch in diameter and 30-40 feet long are wonderful to hold and pull.
Terrwyn's 37 foot, 20,000 lb. displacement dictates the size and pressure on these working lines (running rigging) and the size of the various sails. The sizes and forces involved are about as great as one man or woman can generally manage without power assisted devices i.e. electrical or hydraulic powered winches. We have a 1/2 dozen mechanical winches and as many simple pulleys to increase our strength to adjust these lines to hold the sails and poles in place. And they often require adjustment as wind and speed and direction change. Nothing "fiddly" about these ropes and they are so lovely to hold.
On my previous boat and in racing situations 7 or 8 guys did this work, but here it's just we two (and Monti). So we take longer to do most sail changes but still do all the same work. Fortunately the joy is in the labour not just the fruit.
Bill the Sailor Wannabe