Monday, May 04, 2009

Bermuda Triangle Weird

At Sea
28 32.55 N 077 48.31 W

The sailing weather is delightful. As a matter of fact, we have been using our spinnaker at sea. We never did that before. With the spinnaker we're managing 5 to 5.5 knots average speed in light wind and calm seas. We're loving it. Our progress for the first 24 hours is 125 nautical miles. (143 statue miles), not bad.

Jim got a touch of seasickness yesterday but Libby gave him a Bonnie pill and that cured it.

Yesterday afternoon, just as we passed the northeast corner of the Bahamas Banks, we encountered a really weird spell. All of a sudden, our speed changed from 5 knots northward, to 11 knots toward the southwest. That's almost moving backward. I fiddled and fussed with the sails and the rudder, trying and failing to get control. It seemed that we had a sudden dramatic wind shift that made the sails collapse. Anyhow, Jim and I scrambled to get the spinnaker down and the jib up. Libby stayed at the helm. After 10 minutes with the sail change, we returned to the cockpit to find that Libby had everything back in control. Once again we were going nearly 5 knots northward.

So what happened? I have two theories. Unfortunately my recollection of the relevant facts make it impossible for me to rule out either.

Theory one: We met up with a particularly strong swirl of current, 15 knots or more in speed. Evidence against this is that no effects on the water surface were seen. Evidence for it was the shift in apparent wind which could be explained exactly with a strong current. Further evidence of a swirl was that we sailed out of it within 15 minutes.

Theory two: There was no real anomaly, just a period of non-convergence and bad readings from the GPS. Every once in a while, the GPS loses a satellite or otherwise screws up. The symptom is bad position readings and implied velocities that aren't real. What about the wind shift? Well, my memory of the incident is not precise enough to remember whether or not I fiddled with the sail and rudder before or after the wind shift. Evidence against: always in the past, GPS anomalies lasted 30 seconds or less.

You're free to ascribe the whole thing to one of those Bermuda Triangle mysteries if you like. The kind that causes ships and airplanes to lose their way and disappear.

New Subject: I didn't expect to see any ship traffic last night. However, around 5AM I was alone in the cockpit standing my watch. I saw a light on the horizon to the east. I looked like a ship. The color was reddish. I took a bearing on it. I looked for a blip on the radar -- nothing. When I looked back a the light again it seemed much brighter. Wow, it must be close. A few minutes later again it seemed elevated above the horizon. It must be a masthead light on a sailboat, I thought. Wait a minute! It is Venus! I sure got fooled. I checked with the Stellarium program on the PC. Yes it was Venus. But Stellarium also let me know that Mars, Uranus, Neptune and Jupiter were also in the same section of the sky with Venus. Uranus and Neptune are too dim to see with the naked eye but I saw the others.

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