The Offshore Voyaging Reference Site

The Secret Life Of Your GPS


Raise your hand if you don’t rely on GPS. Any takers? No?

Now raise your hand if you understand what your GPS is doing when it concludes “You are HERE”. I don’t see many hands this time, either.

We have reached an interesting situation, where many (if not most) sailors entrust the safe navigation of their ship to a little black box whose operating principle is known only by a rare few.

You don’t need to understand how GPS works in order to use it. Nevertheless, it is undeniably interesting—and a bit humbling—to delve into the inner workings of our favourite navigation tool.