It is about 285 miles from Cabo to La Cruz Mexico and it's supposed to be all downwind at this time of year. Ha! Our Poobah had relayed the weather report calling for light NW winds and low swells for the next few days for those heading South. The good news was: the prediction was accurate. The bad news was: the prediction was accurate. Figuring that our normal fuel capacity of 88 gallons would support motoring well over 285 miles, we had decanted the eight jerry cans into the primary fuel tanks. As it turned out it was a quiet Princess Cruise all the way.
How dull was it? Well the big excitement was a small flock of birds that took up residence on our rigging for nearly twenty four hours. At first we took this as a just another wildlife sighting similar to spotting seals or dolphins. (Nobody thought it was on the scale of a whale sighting.) There seemed to be a pecking order as some birds sat at the mast head and others on the spreaders. Some were actually chased away by birds that had already secured their own perch. All very entertaining. As time went on and we saw the guano coating the deck, we took a more negative view of the bird siting. We tried several attempts to dislodge the birds to no avail. Finally, for no reason known to us they all left.
Late on the second day out we spotted two floating logs. In nearly 5,000 miles of open ocean sailing I had never seen two logs within an hour of each other. I feared that as dark was upon as we were making about 7 knots that it would be prudent to slow the vessel. Kinetic energy is calculated as .5 times the mass of an object times its velocity squared. That means that slowing the boat to 5 knots would cut the energy available for a collision by one half. I had no way of knowing what the right number was, but cutting our crunch energy by half sounded good to me. In addition, I used the chartplotter's ability to predict estimated time of arrival to calculate that slowing the boat would put as at La Cruz at daylight. With two good reasons in hand, I slowed the boat.
You Picked a Fine Time to Leave Me Lucille
All sailors seem to name their autopilots--the most common name being Wanda (Wonder). On Virago it is the Raymarine chartplotter that will forever be Lucille to me. I used the Raymarine planning software to plot my trip from Alameda to La Cruz. The trip was about 1,500 miles and called for five landfalls: San Diego, Turtle Bay, Bahia Santa Maria, Cabo San Lucas, and La Cruz. I planned to use the same chip in my Raymarine onboard system to drive the autopilot.
The only part of the trip that caused me concern was the five mile wide passage between Punta de Mita and the Three Little Marys about 1,485 miles into the trip. I consulted Charlies Charts, Pat Rains Boating Guide to Mexico, and Roger Frizzelle. They all agreed on two things. First, all the charts for Banderas Bay are off by up to one mile. Second, there are uncharted rocks a mile or two off Punta de Mita. Since I would have the ability to overlay a radar image on the electronic charts, I chose to favor the island (Southwest) side of the passage. In that way, I could validate my position with radar reflected from the islands. I carefully checked the registration of the radar images with the electronic chart at the Three Marys as we passed them and at Punta de Mita as we approached it from the Northwest. So far so good--the registration was good. Maybe the electronic chart had been corrected???
I should note that a few hours before we were due to reach Punta di Mita our whole Raymarine system had rebooted on its own. (We were motoring as we had been for over twenty four hours.) When this happens the screen appears to flare up since we had it set on a very low night time illumination. Then the system has to go through its start up that takes about two minutes and requires several keystrokes from the operator. After a few hours of normal operation we relaxed and thought all was well.
We approached the critical passage under power at about 1 AM on a moonless night with otherwise good visibility. About file miles out I could see that the radar image and chart were about one mile out of register for the Three Little Marys. The most critical result was that my waypoint that had been so carefully been set to be one mile inside the western most island was in fact actually on the island! Just then the chartplotter rebooted. It starting rebooting after about four minutes of operation. I assigned Bob to babysit the chartplotter. He went through the sequence more than a dozen times. Meanwhile, I activated "Plan C".
Why "Plan C" not "Plan B"? My plan B had been to us OpenCPN software on my laptop as a standby navigation system. The software will use S-57 vector charts or C-Map charts. The S-57 format charts for all US waters are available from NOAA for free download. I have these loaded into the laptop. I have tried to get the Mexican S-57 charts to no avail. I even heard scuttlebutt that the Mexican Navy had good S-57 charts but has restricted their availability. In addition to the software I have purchased a GPS antenna from Garmin that runs to the USB port on the laptop. All of this was tested in US waters, but useless in Mexican waters without the charts.
Plan C was to use my trusty Garmin XL48 circa 1998. I retrieved it from the nav station only to find that its batteries were dead and that I could not find the cable that would run it from the 12 volt power socket at the helm. I got fresh batteries from Bill Eddy and fired the Garmin up. As always it performed flawlessly. Unfortunately, I had not been loading the waypoints from the Raymarine system into the Garmin. I did write the remaining waypoints down during one of the Raymarine's moments of lucidity. I then checked to verify that the distance and bearing to the mark agreed between the two systems. Once that was verified I knew that we could navigate the remaining distance with only the handheld if need be.
We did spot the western Little Mary island about a mile to our starboard side and cleared the passage without further mishap. I had planned our arrival at La Cruz for dawn since the new marina is not on any of the charts yet. We did need the light to be able to correctly interpret the red and green light pairs of the short entrance channel. Ironically, when I got to the marina and checked my email I had updates to Pat Rains' Boating Guide to Mexico waiting. Son of a gun, it reported that there is a new marina and we were sitting right in it. What a relief!
As we arrived we stopped at the fuel dock, took on fuel, then docked the boat.
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