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Date: 07 Aug 2011 08:07:54
Title: Lesson learned: Navigation - Nord Sea

To sail in tide and currents, experience from the Baltic sea has no value at all. I'm happy I took an Ocean skipper the previous winter. To be able to calculate currents and water levels I must have paper charts (probably old fashioned). Every leg on the journey has been planned on the paper chart, in the beginning with pencil, but it was hard to see in bad weather etc, then I learned to use tape that I apply on the chart and then draw with water safe pens, when done or something has to be corrected, just pull off the tape and apply new.
The currents have been drawn on the chart with arrows and indications on speed etc. If we had to get into an area at a certain time, that has been set on the chart, for instance: Entrance Elbe, -5 to -3 HW Helgoland (Meaning we can only get in -5 till -3 hours before high water in Helgoland), then I put the times of high and low water for that date on the chart as well.
Why? Because when the gale screams in the rig, the waves hunt you down and rain makes it almost impossible to look forward, you don't get to smart.
The worse experience that nobody told us about the North sea is that it is so shallow. When we had 20 meters of water under the keel we smiled. Shallow water makes for very nasty waves and fast currents. In some places it looked like we where sailing in a huge river flowing over rocks etc.
We used charts with a large scale from Imray that are water proof, for the english channel just three charts.
They have a scale big enough for good planning and small enough to give you the big pictures of depths etc.
On top of that we had our Raymarine plotter that came with the boat, unfortunately it uses C-maps and they are very expensive.
The good thing about the plotter is that it has a big screen by the navigation table and a repeater in the cockpit, and the repeater is just as functional. Radar is also in the system and Radar made a huge difference for safety, we had so much fog and rain and we could sail in the night without worry. So C-map had all the details that the big scale charts did not have. As a backup we used an iPad with charts, it worked very well and was very useful when we had to navigate from the wheel. That happened only on the way in or out of a harbor. The nice thing about having two systems is that; believe it or not they have different information...
Which to go for? Well thats when you have to remember the reality...
I will get back to the electronics in lesson learned - equipment.
What if? Is always the question on board, what if all our electronics would be hit by lightning and die?
We had the paper charts that could take us to an entrance and then we had the pilot books with small scale charts to enter the harbor. We also plotted our position every hour on the paper chart, which is common sense on every boat leaving the coast (we guess).
It cannot be underestimated that planning is everything in the North Sea, if you know the current you do not end up beating it or being dragged onto a sand bank.
Lesson learned? We had no mishaps, but it is terrible to just be one person on board that makes the calculations, we have to be two so we have one checking the other. This will be corrected this winter, Ellinor has to learn the tides.
Lesson learned? We have to look and think about how to set up the long haul, C-maps are so expensive that a few of them can pay a new plotter. The iPad is great but you cannot rely on it without a proper source of power (it runs 10 hours on one charge), and the iPad does not work well in hard sun ( that was no problem until we came home), the iPad with a good watertight cover works well as long as you don't stand in hard rain, because the rain starts to change the menu by force, the case itself is very good though. More about it on http://www.soltek.se/ (you have to use Google translator from Swedish to English).
Lesson learned from literature on board, before you buy pilots and guide books check them really well, information needed is a good plan of the harbor and entrance, currents in and out, how to contact the harbor ( missing in some books) is very safe and makes life easier so you know before hand what to expect. Imray seems to have the idea that every book you buy shall lead to another purchase, very irritating when you look into a pilot and it tells you to buy another book to get the currents. well that is not so easy out there!

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Ipad in it's case



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Raymarine repeater in Cockpit, great tool even if it is 5 years old. To the left our AIS transponder-receiver

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Raymarine plotter with radar on, paper chart and under it is the bible of the Nord sea: Reeds Almanac where you have all the tides, currents, harbors etc etc. By the way, once I used the tide table in the plotter, and it was wrong! For some reason I checked in the almanac to make sure and could avoid a scenario before it happened.

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The iPad where it made most of its job, enter a harbor or critical water, it has a holder by the wheel.


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When you do your planning on paper you will find others getting interested in what's going on, Erica 7 years old understood very well the connection between time we have to sail and length measured on the chart.




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