Wednesday, March 23, 2011

Charts, Charts, Charts

Michael and I have spent the last few days going over hundreds of charts for the South Pacific and Australia, belonging to several other cruisers who have them in their libraries.  Talk about overwhelm.  How does one decide which charts they need? 

To begin, we have electronic charts of all of the South Pacific and Australia.  They will take us wherever we need to go, and have great detail as you zone in on entrances to atolls or harbors or anchorages.  But there is always a risk that your electronics will crash due to a lightning strike, or just plain no reason at all.  We also have cruising guides which include local detail for the more popular cruising spots. Some of these guides are electronic, and some are paper.  So it’s always prudent to be sure to have backups in the way of paper charts for wherever you think you may be going.

We started with some good overview charts to assist us in plotting our course.  We have a large one that covers the whole central and south Pacific Ocean from Mexico to Australia.  We’ll likely chart our course on this one as we cross, marking it twice a day.  Any more than twice a day will make us feel like we're going backwards.

We then have overview charts of different sets of islands, like a chart that covers the Marquesas to the Tuamotos, and then the Tuamotus to Tonga, and so on.  We’ll use those as we make our passages between the islands.

We then have charts of smaller areas of islands, such as just the Marquesas, just Tahiti, and so on.  These have a nice amount of detail to get a good overview of what’s out there, but other than for French Polynesia (which we got in a nice small booklet), we do not have charts with good detail for entrances to anchorages.  We are hoping our guide books will cover us for those.  Having said that, that’s where you can run into trouble with reefs, cones, and other wonders.  In addition, charts are not always completely correct, and with the reefs, even being off a foot or two can make all the difference as your depth sounder says you have 20 feet below you and then suddenly you have none. It's for this reason that we know never to enter anchorages when it’s dark. In fact, it's important to enter when the sun is low, either in the morning or in the afternoon, with the sun behind so that it casts a shadow over anything in the water that can cause you trouble.  Either Danielle or I will be high up (possibly up the mast) scouring the water for anything that doesn't show up on the charts, ready to shout to our captain that he must back up immediately.  And apparently the anchoring is very different in the South Pacific than in your average sandy bottom Mexican bay, because of these coral reefs -- which, I'm sure, will be the subject of a future blog. While this all sounds so daunting to me now, I am sure we'll get used to it. On the bright side, we hear that the visibility in these waters can be as much as 70 feet.

Back to the charts. So where do we find the charts we need?  We started at the nautical book stores in the Bay Area when we were there a few weeks ago but didn’t get very far.  Had we had more time, we could have ordered a set of everything the experts think we’d need from a wonderful service called Bellingham Charts.  But we knew that there were resources, less expensive although not as convenient, in Banderas Bay.

When we got back, we met with other cruising friends who have sailed the South Pacific to see what they had and what they felt was most important to have.  Our friends on s/v Blue Sky were an amazing help. In addition, at Marina Vallarta, Steve on s/v Kavenga has an incredible lending library in his land home.  Michael and I spent 3 hours in his ‘chart room’ (i.e. his bedroom) – he stores all the charts in order under his bed.  We spent a lot of time in giggle/exhaustion mode:  How are we supposed to know what we need?  And then once deciding on the approach, how are we supposed to pronounce the names of all these islands (Tahaa, Upua Oa, Malitiki, Hiva Oa, Fatu Hiva…), let alone the names of the bays and anchorages and towns and cities?  Which anchorage goes with which island?  Which island goes with which country/island group?  This is certainly a lesson in geography.  We'll have several weeks at sea to figure it all out.

Another interesting side note:  Some of the charts we looked at date back to the 1800's.

We got through the chart sorting exercise and we now think we have what we need.  So, many bus rides, hours and hundreds of dollars later, we think we can check ‘charts’ off our list.

Onto the next item.

-Barb, in La Cruz de Huanacaxtle, Nayarit, Mexico

3 comments:

  1. love the preparation posts. looking forward to hearing about the food plans!

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  2. You probably felt this same anticipation on your initial trip - with some help and advice given from your crew. And look what you've accomplished on your own - masters at charting Mexico's west coast waters, as well as pronouncing all those Mexican towns correctly! What excitement awaits you in the South Pacific!

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  3. I guess there's no such things as "winging it" when you are at sea.....how could you not have given this experience to your kids???
    Miss you a ton!!!

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