Day 7 - Autopilot OK

I had my rice and fish meal last night - rice boiled with an onion and carrot, the sardines heated separately. It was the first "meat" that I had eaten since my last night in Brazil and I enjoyed it though to be honest I am just as happy with the beans. I could only eat half of the food, so I'll have the other half tonight. That means that the 19 cans of sardines in tomato sauce on board would provide main meals for 38 days - all of the way to Cape Town. At the rate at which I am eating these days I've probably got enough food on board to last a comfortable 6 months.

I had a pretty active night dealing with the light at somewhat variable wind. Several times I had to go topside and make adjustments to keep the boat moving, and I got through the bulk of the night with the autopilot managing the steering. It must have been 3 AM when I woke up to find the wind stronger. I went topside to engage the Monitor wind steering but try as I might I could not get it to hold course. It was a worry but I decided that it would be best to leave the problem until daylight. I prefer to use the Monitor because (1) it follows the wind rather than a hard course (2) it does not spontaneously disengage like the autopilot does.

I wanted to monitor the course of the boat from inside of the cabin (not just the nav station) so that I could verify from my bunk that the autopilot was still engaged. Until recently this has been a problem because the two big speakers of the boat's sound system induce too much distortion to a compass mounted on the forward bulkhead. It was time to break out the surface mounted compass that Bob Carroll had given to me in La Paz. At first look the bearings were all backwards, it N&S, E&W swapped. It took me a few minutes to figure out that the compass was designed to be viewed not from the top, or even along the lubber line, but from the side anywhere around it. The compass came in a sturdy blister pack on a thick card 8" x 10". I laid the card on a non-skid pad at the aft end of the main table and found it to be very stable. Until then I had assumed that I would have to permanently glue the compass to the table - in fact, the photo suggests that the base has a peel-off glue surface and the compass is designed to be fixed to the dashboard of a car. But I was now pleased to see that I could lay the entire blister pack on the table when under sail and put the card away when in port. The boat was headed SE and from the bunk the line from my eye through the center of the compass and beyond was NE, and NE was what I should see whenever I woke up. It was a simple solution to a nagging problem and I was grateful to Bob for his useful gift.

I made sure that I was up again at 7.30 AM to tune in to the Brazil weather fax service morning schedule. Unfortunately as with the evening schedule the previous day I got nothing. I cannot understand it. I asked a few people ashore and nobody seemed to know much about it. I sent a query to Sailmail technical support and got no response. I scoured the internet and found no reports of problems, and all of the schedules and frequencies that I saw were consistent. I've given up and will hang out until I get within the area of weather fax coverage of South Africa, at longitude 20W. I've actually seen S Africa's wfax signal from the E coast of S America, so expect no trouble in availing myself of their service.

By then the wind had picked up a bit and I engaged the Monitor, but try as I might I still could not get it to hold. I was still sleepy and had not had coffee but it was daylight and I had to solve the problem. I experimented with the air vane, pushing it from one side to the other to simulate off course situations. I soon realized that the water paddle was swinging only a small amount of potential to the starboard side. Every experienced Monitor user will already know what the problem was, that the line-driven Monitor hub on the wheel was rotating so much that the pulling line was acting on the hub directly rather than along the arc of the hub. The point is that the Monitor was OK and I had gotten more valuable insight into managing the control lines.

Our position at noon was 30S50, 38W13, yielding a surprisingly high n-n distance of 113 miles in the direction 110T (ESE). I was surprised because most of the previous 24 hours had been a struggle to keep the sails up and the boat moving in feeble winds, and at times our boat speed would drop to below 3 kts. We were 1350 miles from TdC which was on a bearing of 106T. We had closed so much on the island because the 113 miles of the day had been almost directly toward it. Also, the pilot chart shows us to be benefiting from a current of 0.5 kt set to the SE, which represents 12 miles per day. We were 580 miles from our departure point at Angra. The barometer had dropped 3 points to 1018 hPa.

By noon the wind had swung to the NNE, an indication of the coming high winds, which were still a day away. The latest grib file predicted 26 kts from the NNW in the vicinity of my latitude of 31S. Were I be to at 34S I would be expecting 32 kt winds. During the blow I will likely drop the mainsail and run downwind with a suitable amount of jib. I cannot run downwind with both the mainsail and the headsail, since the mainsail will blanket the headsail, and in any event I hate running downwind with the mainsail because I'm terrified of a gybe, preventer or no preventer. Running before it will reduce the apparent wind a useful 4 of 5 kts.

The "house" battery bank was at a healthy 12.9V following the previous day's 3-hour run (making a total of 5 engine hours since leaving Brazil). The starter bank was at 12.8V. I am very careful about shutting off the exhaust valve when the engine is not in use and remembering to open it before starting the engine is now second nature to me. However, yesterday I discovered a flaw in my procedure. I shut the engine down then closed the exhaust valve. Later I decided to hit the button to shut down the engine's electronic management system and thought "Shit, all I have to do is hit the starter button instead of the electronics button next to it (a very easy mistake to make) and I'll blow the exhaust hose." I have changed my procedure and I will in future shut the exhaust valve last, after all of the panel button pushing is finished.

As usual the bulk of the morning cloud dissipated, leaving a mostly clear sky with a sheen of light cloud. There was constant sunlight, sometimes weak and sometimes very strong. The temperature was still mild, suitable for sailing in underclothes. Wonderful cruising.

I took advantage of the pleasant conditions to explore the problem with the autohelm, namely that when hitting the +1, -1, +10, -10 buttons to adjust the course in a 1 or 10 degree increment, the steering would go nuts, with the wheel gyrating wildly back and forth. I put together what I knew. There could be no problem with the head itself because it was brand new. The autopilot was receiving heading data from the flux gate compass because I could see the numbers changed as I turned the wheel. It was also receiving data on the angle of the rudder because I could see the rudder angle display changing properly as I moved the wheel. The linear drive had nothing to do with it. The problem might be in the course computer, in which case I was dealing with a sad coincidence. To me that left calibration as the most likely bet because the new unit had arrived with factory defaults and I could well imagine the technicians in Mar del Plata setting the head that they repaired to factor defaults.

I had two manuals to work with: The thick and detailed one that was on the boat when I purchased her and related to the original head that was replaced in Adelaide, and the thin dumbed down one presumably deemed more user friendly to modern sailors. I wasn't sure what elements of the original manual applied to the newer head, so I worked with both manuals. I figured that "rudder response", "rudder gain", "pilot type", "rudder damping", and "rate level" were the most likely factors. I then managed to get into "dealer calibration", a process hidden from new users for some reason, but explained to earlier users, and went through each setting. Most were OK, but the one that I think made the difference was raising the rudder damping by 2. As a target of opportunity I also cut down the limit of travel of the rudder for 20 to 15 degrees to make sure that the autopilot does not force the steering mechanism below onto the blocks. I then backed out of calibration mode, disengaged the Monitor and put the boat under autopilot control and waited for everything to settle down. I then hit the "-1" button and the wheel made an imperceptible movement to make the adjustment instead of going wild. I then hit the button 4 more times and that settled down OK, with the new course 5 degrees less than before. I then hit the +10 button and the wheel moved enough to make the new course which made a net gain of 5 degrees to the heading. I then tapped the "-1" button 5 times to return to the original heading. It all worked fine! So now I had a fully functional autopilot again, and I was understandably pleased.

This means that the head that was repaired at Mar del Plata was also fully functional. I will keep it as a backup and may even swap it back into service in Australia to assure myself that creeping corrosion from the salt water invasion hasn't damaged it. There is more work to be done with the autopilot. The compass must be swung (It told me so.) and I need to sort out issues of variation and magnetic vs true headings. I also want to explore steering relative to the wind rather than steering to a course. But these issues are not terribly urgent and can wait for another day.

I had a very pleasant hour in the cockpit enjoying a beer. While I was out there I noticed 4 or 5 petrels, though I don't know if they were all different visitors. This part of the ocean isn't quite as barren as I had thought. It's all a matter of spending enough time topside looking. At 8 PM I climbed down into the cabin so relaxed that even my teeth felt loose. I put the pot with the rice and fish on the burner and planned to finish the movie "Nixon" after dinner.

At 11.30 PM the boat was sailing peacefully with a 10 kt NNE wind off the port beam, making 4.5 kt to the SE. The sky must have been fairly clear because there were plenty of stars out. I was looking forward to a quiet night.

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