Garmin’s GDL 39 has been one of the best-selling ADS-B receivers since it was introduced at Oshkosh in 2012. It combines a WAAS GPS, subscription-free ADS-B weather and dual band ADS-B traffic in a single unit, and has proven to be very reliable. We’ve flown with it extensively and can recommend it as a great way to make your Garmin Pilot app a lot more powerful. In addition to its compatibility with iPads and Android tablets running Garmin Pilot, the GDL 39 can also be connected to portable GPSs like the 796 and aera 500.
About the only feature the GDL 39 lacked was a built-in Attitude Heading and Reference System (AHRS) for backup attitude. Other ADS-B receivers like the Clarity and Stratus include an AHRS, and pilots have come to appreciate this “worst case” backup function. To answer that request, Garmin has just introduced the GDL 39 3D.
The GDL 39 3D is the same size and shape as the original GDL 39, and works almost exactly the same–so there’s no need to re-learn how to operate your tablet. But in addition to the moving map, traffic and weather information that was previously available, attitude information is presented on Garmin’s popular panel page. The panel page can be viewed as a split screen in the app, which makes for a really polished and intuitive presentation.
Just remember that, like all ADS-B receiver/app combinations, the information is for backup use only. The speed and altitude indicators, for example, show GPS data, not actual pitot-static data. Still, in a true emergency, this split screen moving map and panel page could very well be a life-saver. The attitude indicator updates multiple times per second, so it’s smooth.
Note that attitude information cannot be displayed on portable GPSs, only iPads and Android tablets. Full compatibility chart is below: