GLONASS

There is the common wisdom GPS works outdoors only. Which used to be true. But the performance of consumer grade navigation devices has been surprising recently. This post is an addendum to the last week's Garmin fēnix story. The fēnix (or the D2 Bravo in my case) exceeded my imagination on GPS capabilities. A number of times, as a passenger, I tried to log a track of a flight. Sitting at a window I tried holding a phone close to it but every now and then it was losing the signal.

The fēnix on the other hand works effortlessly even on an aisle seat on the lower deck of a 747. It even keeps working in a lavatory which is situated centrally within a fuselage, far from any window, inside an all-metal plane. On a 9-hour trip across the Atlantic it logged about 26 thousand waypoints, which is about one measurement per second. The "Fly" activity application was continuously showing instruments panel displaying altitude, speed, heading and other data, almost as I was sitting in a cockpit.

I'm not an expert on GPS receivers, but this performance is very likely to be attributed to the dual GPS-GLONASS receiver. When I was disabling GLOANSS through the menu options it was losing track immediately. After enabling GLONASS back, it was locked back on within less than a minute (bear in mind commercial aircraft flies at 500mph). While the conventional wisdom is the Russian GLONASS does not offer any significant advantage over the American GPS, my fēnix experiments prove this to be different. Or may be the two systems combined in the Garmin package are able to deliver this outstanding level of performance.