Aletta's Saga

We arrived in La Paz this morning, 51 hours out of Mazatlan.  The first day we had 10 or 12 knots of wind and were able to sail for about 8 hours.  Although the wind was blowing from the direction of our destination, weather forecasts indicated that it would shift more to the north, a change that would have been much appreciated. The expected wind-shift never materialized, however. It was fun sailing while it lasted. We were close-hauled under main, yankee and genoa-staysail, with Rangval, our Monitor vane gear, steering flawlessly. At dusk, I reefed the main and lowered the yankee, thinking reduced sail would make for an easier night. This proved to be a mistake. The seas had become very lumpy and with less power in the sails NS could make little progress against the waves. We turned on the engine and we began to move in the direction we wanted, albeit slowly. I hand steered for awhile, then decided to see what Aletta could do.

Let me introduce Aletta, our Simrad TP32 tiller pilot:

Aletta

I know that this picture is cluttered, but the TP32 is black and looks something like an over-sized first generation cell phone.  The silvery stick that looks like an antenna is actually a rod which connects the TP32 to the tiller and drives the tiller back and forth.  Notice at the left side of the picture the TP32 rests on a stainless steel block which is attached to the cockpit coaming.  You can't see it, but a stainless steel pin, a quarter inch in diameter, protrudes from beneath the TP32 and fits into a vertical hole in the stainless block. That is how the TP32 is attached to the boat.

You may recall that I named our Monitor vane gear Rangval after my paternal grandfather. I named the TP32 Aletta after my paternal grandmother.

Why both a vane gear and a tiller pilot? Shouldn't one steering mechanism be enough? Well, a vane gear gets its direction from the wind, and if there is little or no wind, it will not work. A tiller pilot gets its direction from a built-in compass, and ignores the wind.  When you are sailing, especially to windward, it is preferable to get the direction from the wind, because then the heading of the boat relative to the wind stays the same and the sails are always properly trimmed.

NS weighs somewhere between 20,000 and 25,000 pounds. Usually boats as heavy as NS have wheel steering. There are advantages to a tiller, however. When steering by hand, you have a much better feel for what is happening. It is also easier to attach a vane gear like Rangval to a tiller than to a wheel.

A Monitor vane gear has no trouble steering boats much heavier than NS but the largest available tiller pilot is rated only for boats up to 16,000 pounds. Because the greatest stress on an autopilot comes under sail, I had decided to use Aletta for motoring only.

That  first evening out of Mazatlan, we still had the mainsail up when we started the engine. The main was helping to damp the rolling motion of the boat and probably added a bit of speed, as well.  We were motor-sailing.  I had Rangval for sailing and Aletta for motoring, but up to that moment I only had myself or another human for motor sailing.  Did I want to risk destroying Aletta by making her motor-sail in rough seas? Or was I going to hand steer NS all night long? I decided to give Aletta her chance.

And she did great. Why had I doubted her? Aletta steered NS for the next forty hours, with main and engine. Was this dumb luck or will Aletta be able to continue to do this in the future?

One thing I have learned from coastal cruising here in Mexico is that most of the cruising sailboats are either motoring or motor-sailing most of the time. I had been thinking that when NS got back to Seattle I might invest in a custom-fitted autopilot, which would be much more costly than a TP32. If Aletta can handle the load, we won't have to wait until we are back in Seattle to get a solution to the problem and we will save money. Forty hours is a good test, but certainly not definitive. Time will tell.

Our current location in GoggleEarth format is 24 09.325'N,110 19.582'W