Navigation Redundency

[Safari38LH]

2 Simrad NNS, 2 iPads with iNavx and Navionics, 2 iPhone with iNavx, paper charts.

[Adelie]

Originally Posted by noelex 77

You do need to take some precautions such as having multiple backups and one system in a faraday cage is a good idea. With the low cost of both the software and hardware this is now quite feasible.

A Faraday cage is no guarantee against lightning, it just improves the odds.
It does nothing at all for coronal mass ejections and disputes with folks that have anti-satellite weapons and then there are all the myriad ways that the electrical system can go down. And the spare batteries get drowned.
Individually these are very low probability events. Together they are just low probability.

[noelex 77]

Originally Posted by Adelie

A Faraday cage is no guarantee against lightning, it just improves the odds.
It does nothing at all for coronal mass ejections and disputes with folks that have anti-satellite weapons and then there are all the myriad ways that the electrical system can go down. And the spare batteries get drowned.
Individually these are very low probability events. Together they are just low probability.

I agree lightning is certainly the biggest concern when relying on electronic mapping.
If you get a severe lightning strike all bets are off. Thruhulls evaporate, holes get blown in the hull, the mast falls down etc.
These events are fortunately very rare. The loss of maps in these circumstances is likely to only be a minor issue. In most situations the boat could still be safely managed even if no pilot books etc are available.

A simple solution is to print a few emergency paper maps from your electronic maps to cover the voyage.

The electrical system on boats is has got more reliable, with multiple batteries and sources of power such as solar panels etc. Tablets, phones laptops and HH mapping GPS have their own battery supply. Electronic maps for these devices are inexpensive and many cruising boats are accumulating these at rapid rate as technology marches ahead and older devices are superseded.

My own boat has electronic maps on 10 devices, more than most, but these sort of levels of redundancy are becoming common.

Given the limited need for maps offshore most of these devices have enough capacity in their own battery supply to complete any voyage.

This is not foolproof, but there are more vital systems that have a higher chance of failure.

[Ecoaster]

thanks for all the replies, I have a Garmin2010c a handheld gps and the standard back-up chart books and charts. Now i`m in search of the most reliable wx app or service. In past cruises I`ve used Chris Parkers custom wx forecasts.

[Kenomac]

Paper charts are a must have. We're very happy with INavx for ipad. We have 5x redundancy onboard including Paper, two ipads with internal GPS and InavX, Garmin for ais with basic world charts and Nobeltec on the laptop.

Paper is still the only one I will not give up!

I've run into knuckleheads a number of times with F%#ked up ipads, or chartplotters who were totally lost and didn't know what to do because they didn't know how to read a paper chart and use a compass. Or... they're totally shocked to find out their stupid cell phone doesn't work a few miles out. Idiots!