On Seawind catamarans navigation equipment is B&G as our primary navigation system. Similar to Simrad, Lowrance, B&G is part of Navico and I like it for its functionality, partly open network architecture and possibilities to integrate it with PredictWind etc. I choose the Vesper Cortex solution as far more superior then the B&G VHF60 solution.

We opted for the full package:

  • B&G Zeus3S 12″ Chartplotter
  • 1 extra TRITON2 4.1” MFD
  • An autopilot NAC-3 CORE with a PACK RF25N rudder feedback unit and a Precision-9 solid-state compass and remote control
  • Triton2 display
  • Depth ad speed transducer
  • Vesper Cortex AIS / VHF solution
  • including all NMEA 2000® cables and connectors.
Base set of B&G Navigation equipment
Basic for navigation equipment

PC components

I will add a Windows PC and a Android Tablet (and a Android phones) to the package. Connection on board is via Wifi (Zeus3) or via a Mobile SIM Wifi router. We have 2 portable SDD’s for backup as well as entertainment, mostly music, a few movies and ebooks.

I forced my Windows PC to stay on W10 to be able to use it offline, security updates till 2025. I use a Windows PC because SAS.Planet is only Windows. We run the Navionics Boating app as a backup on Android Tablet and Phone. We bought the chart of your sailing area, it will function offline and update when in reach of internet.


There is a choice of Navionics of C-map plotter charts. I did some research and wrote a post on it, C-Map vs Navionics charts. C-Map Discover is our choosing, there extra large (former Continental) maps for the plotter will be our primary solution.

Secondly we are using SAS.Planet as stand alone application on the Windows PC. An alternative is, to convert a SAS.Planet satellite image file to AT5 format which B&G can read and incorporate as a layer. This is a complicated procedure, best explained in a YouTube from SV No Regrets.

The C-map app on Android is getting there but still a bit buggy and clumsy. The latest version is still Beta, and not available for the general public. Satellite images are added but SAS.Planet is still much better.

Because planning on a screen is always a lot of zooming in and out, I generally buy a Planning Chart of the area, for example British Admiralty Nautical Chart 4008 A Planning Chart for the North Pacific Ocean. It’s also my paper and progress backup on board.

Celestial Navigation

No theoretical explanation, just a short “things to do”

  • You always need a nautical atlas, so get the one from Skrypkin Maksym, simple and offline. Need to be On dock find a spot to do your readings. Choose a stable position and measure your high above the waterline. Find in the nautical almanac the DIP correction.
  • 2. Find on NOAA Solar Calculator your Local Apparent Noon.
  • 3. With a minute or two before when you think your LAN will occur, take some shots of the Sun, making sure that you have a crewmember making note of the time. The highest reading is your LAN.
  • 4. 

Preparations and circumnavigation of a Seawind 1260