On Bella Luna we only use electronic charts for navigation.  I often hear people saying that is not safe just relaying on electronic navigation.

I think it is fair to say; you should always have a backup plan, independent if you are using electronic navigation or paper charts.

On Bella we carry a number of standalone electronic backup alternatives.

The aviation industry is changing to electronic navigation.   One advantage being in a boat instead of being in an aeroplane is that we can actually stop the boat if we are not certain of the position.   That luxury you do not have in the air!  I have surprised myself forgetting this obvious option when being disoriented in the Swedish archipelago.  Continuing in full or reduced speed in the archipelago is not a good option if you are not sure what is in front of you!  After stopping the boat, it is much easier to get your bearings right as you are not working under stress any longer.

If worse came to worse I´m sure most of us would find our way in to a safe harbor without charts, even if it would be exiting.

Here are some examples of arguments I have heard over the years, why it is irresponsible to sail only with electronic charts.

“What do you do if power is lost and you have a blackout?”

“What do you do if lightning strike destroy all the electronics?”

“What if the GPS system is turned off?”

All of above are valid concerns. Lets look at them one by one.

Black Outs:

In my 40 years of sailing a blackout has never happened.  This is off course not to say it could not happen.  This is why we have a  backups that work on their own battery.

A number of computers are on-board. They all have internal batteries that last 5-6 hours. With a GPS puck they work great as a stand-alone backup.

In addition to that we have one IPAD and one IPHONE with the Navionics APP.  As both have built-in GPS, they can serve as a stand-alone backup.   With a fully charge IPAD we could probably sail around for a week without having to recharge, as I do not need to have the device on all the time.

But perhaps more important, I´m sure I could restore emergency power in any event, within 30-60 minutes.  I recommend you to familiar yourself how your boat is wired ahead of time and carry basic material for a “MacGyvor” solution.


This is probably the most likely event for causing a problem.  Even if the risk for a lightning strike is much higher in a sailboat on open water, it is not that common as you might think.  Nevertheless it is a good idea to keep some of your backups in a safe place as sensitive electronics can be damaged by the static air around a thunder storm.

If hit by lightning, it will be lots of damage to electronics.   I´m sure you heard about Faraday’s cage, the idea is that everything is safe inside the metal-cage for when lightning hits.  How safe it is in reality, I´m not person to answer.   But yes, putting your backups in a metal box, is probably the best alternative to protect your electronic backup solution. Your oven is one alternative.  Do not forget to take the IPAD out before cooking!

GPS System turned off:

First, it makes no difference if you are navigating with electronic or paper charts, as the GPS just gives you long/lat.  You need position independent if you are using electronic or paper charts.

If position is lost when you are sailing in coastal areas your radar, echo sounder and compass will be very useful.  On open sea, the old fashion sextant could be invaluable.

It is not very likely that the GPS system would shut down, as most logistic services would stop worldwide, with enormous economic consequences.   In an event of a major military conflict it might be possible, but then I´m sure we have other problems to deal with!

It is more likely that you lose GPS position due to a problem onboard your boat.  Get familiar with how your system is installed.  There are most probably several connectors between the GPS antenna and the Plotter.  Every connector is a risk factor.  Troubleshooting normally starts with checking the connectors.  A backup could be a spare GPS that plugs in directly on the backside of the Plotter.

The advantages of electronic charting are many and obvious.

One important feature apart from the obvious is that is easy to update the charts.  I was not very good at manually adding updates in my paper charts.  Most of the charts I had on-board were well out of date.  This has changed with electronic charts.  Updating electronics charts is normally only a mouse click away.

Updated Chart to the left

Updated Chart to the left with Tuna nets outside the inlet to Faro Portugal.


“Rocks does not move” and therefore updated charts are not that important you hear sometimes.  Rocks do not move, but new are found!   More important is that there are new man-made obstacles like buoys, fish farms etc. showing up every year.  When you do coastal night-sails you are constantly close to fish farms and buoys.  Hitting a buoy in 7-8 knots will make a lot of damage to your boat.

In most countries updated charts, are mandatory .  In some countries Paper Charts are still mandatory.  You might want to check what the rules are in your sailing area.






4 thoughts on “ELECTRONIC CHARTS

  1. Avi

    Interesting that the argument continues after so many years….I suppose that
    much of it is a matter of trust. It used to be regarding the “acuracy” of electronic
    charts, and probably that has settled down even for the purists, but it still makes
    sense to carry some “key” paper ones when you are in a totally new area..

    When i got invited recently to go for a day sail down near Miami, i knew that there
    would be little chance of finding a paper chart aboard..So for my own peace of mind
    I took a screen shot with my IPAD of a chart from NOOA’s website..at least a “form” of
    paper back up to give me something to look at.. of course not very practical if you have
    to put tools on it, but a thought as an additional safety.

    Screen shots I would think are less likely to get caught up in unexpected software issues.
    The other think to remember is that not everyone is as technicaly knowledgeable or
    has your savy with solving electronic issues..


  2. Roland Post author

    Hi Avi,
    I think the important thing is that you have a BACKUP, paper or electronics. Your Screen Shot idea would have been better than nothing. At least you had been thinking about alternatives before heading out.

    I also totally agree that going to sea just relying on Electronics Charts whiteout basic knowledge how your navigation system is wired and configured is not the best thing to do.

  3. George , Yves

    I am a great believer in the confort of electronic navigation . But ,as you say back-up is a must : chartplotters do fail as I experienced with my Raymarine C70 which went blank after 7 years of operation .

    So my standard navigation preparation is :
    -plot the route on paper charts : it gives the best overall view and permit to define the overall strategy taking Wind ,currents and rocks into account
    -copy it on the elctronic chartplotter (Raymarine C90W)
    -copy it on the back-up portable GARMIN Montana ( equipped with full marine charts )

    When navigating , rely on the electronics ; if in doubt back to the paper chart
    On passage , plot position on paper chart (once an hour ) to have a reliable start point for an estimate navigation .

    This may seem time consuming , but it helps you memorize the key elements of your route ; in bad weather or poor visibility ,one gets easily disoriented .


    1. Roland Post author

      Hi Yves,

      Nice to hear from you! This with plotting the position is a good idea. On Bella Luna we use
      Logbook for this purpose. Very nice software that you can run on IPAD or PC.

      We have had nice weather in Sweden the last 2 weeks. Things are heating up!


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