Tag Archives: Zeus3S

SAS.Planet explained

Ok, I looked into SAS.Planet as a standalone tool for offline satellite images as an aid to navigate sparsely populated areas with errors in mainstream navigation charts. What is SAS.Planet, is it legal because it contains a lot of chart content, is it safe to use because its a Russian product, is it tracking me via back doors or extra code?

How does it technically works?

SAS.Planet is a program designed for viewing and downloading high-resolution satellite imagery and conventional maps submitted by internet services as Google Maps, DigitalGlobe, OpenStreetMap, Bings Maps (Bird’s Eye), ESRI and Navionics. But in contrast to these services all downloaded images will remain on your computer and you will be able to view them, even without connecting to the internet.”

After selecting a satellite source SAS.Planet fetches from the internet the view and stores it locally as a gis file. Even a detailed sonar map of Navionics is a call the chart server. SAS.Planet emulates too be an app using an application programmable interface.

Storing it locally as a gis file, called Cache, is nothing strange. And the parameter Internet & Cache is anything a disconnected sailor wants.


Yes, its maintained by a group of Russians, the primary language of the website is Russian and also the default language of the Program. But with Google translate on the site and English as the language in the app, its a useful tool.

The program is written in (Borland) Delphi a slightly older but common programmers language. I checked all internet/server requests while using it and in my opinion, version 201212, is doing exactly what its made for, fetching maps from general internet sources. For example: http://mts1.google.com/vt/lyrs=y@176103410&x={x}&y={y}&z={z}&s=Galileo&scale=1&hl=en

SAS.Planet is 100% file based, the executable, ini-files, preferences and maps are all in a directory. So it didn’t need to write to the Windows registry. It works well on a W10 operating system.

SAS.Planet, a powerful tool for offline satellite images

Using it

In general there are to ways of using is, as a stand-alone tool to study an area or an approach. If you buy a stand-alone USB GPS receiver SAS.Planet will turn into a navigation aid.

A second way is to study an area or approach, save the images and export them in an mbtiles or other format, as explained in this youtube video.

There is a ton of functionality, most not needed for a sailor wanted only to use satellite images. I made a custom version with only satellite maps activated. <link>

march 2022