I thought I would post this in case anyone else is looking at other alternatives to XM Weather, and want traffic in their airplane. I decided to go with the Garmin GDL 39, and so far believe it was a good decision since it offers both weather and traffic in a small lightweight unit. I'll post some screen captures later when I get where I can do that.

Background: I am building one of the CC EX's so the evaluation was done in a J3 (no electric) and on an android tablet running the Garmin Pilot app via bluetooth with the Garmin GDL 39 ADS-B receiver. The GDL 39 receives both FIS-B (weather) and TIS-B traffic on 2 frequencies (978 UAT and 1090 ES). It also includes a built in GPS WAAS receiver to determine position for calculation and display of the traffic and weather. Unfortunately, the GPS WAAS receiver does not meet the FAA rules to also be used for ADS-B out as required by 2020. My suggestion to Garmin, or some other avionics maker is to come out with a lightweight GPS WAAS unit that can be used with the G3X, and the GTX 330ES/33/23 ES transponders. The GPS WAAS is the missing link in having a resonably priced unit to meet ADS-B out regulations for experimental and LSA aircraft. We now have options for everything else.

Test Conditions: My quick evaluation was done both on the ground driving, and in the air. All the air time was spent at low altitudes (what else is there in a J3?) to determine if the signal strength would be sufficient to be usable in the air for most flying time that I do. I spent all my time in the valleys of western Carolina and North Georgia with as high as 6,000 ft peaks above and between the FAA ground stations and me. Driving on the ground were the same conditions.

Initial Results/Impressions: First, I am very enthused by the potential this provides pilots with in-flight information that will make for safer conditions. Reception - excellent! I couldn't leave the status page up all the time and see what was going on with the Map, and traffic pages, but every time I checked, I had all bars green, and I tried to check under the worst conditions. This is really surprising. I will also admit, I am not sure exactly where the ground stations are located, but I am sure that I was blocked from direct line of sight at least some of the time. This included a check of status on the ground taxiing at my small private airport. Weather - Fog was prevalent in the area, along with rain showers to my northwest this morning. Radar imaging was as good or better than I have seen with XM, and clearly showed the heavier/lighter areas. And it is free!!! And with fog in the area, you could easily tell which airports were still fogged in, and which one's were clearing - something I think everyone would find valuable if you needed to divert to an alternate. I didn't have time to check everything like temperatures and winds aloft, maybe I will get time to check those next time. Weather is the main reason for me getting an ADS-B receiver. Traffic - traffic in the area was very light, but I did pick up several commercial flights (distance and separation altitude is configurable). To really get the advantages of TIS-B, as the FAA has blocked this unless you transmit, you will need an ADS-B out solution. There may have been much more traffic in the area than I received or observed, but I was never able to see the ground station triggered from an ADS-B equiped aircraft. I sure wish the FAA would transmit this full time like they do FIS-B. I will say that for what traffic I received, the display was very clear on their direction and altitude.

Quick word on the Garmin Pilot app - it functions just like the Garmin panel units so you will have an easy time setting up flight plans, zooming in, direct to, etc. The one negative is that it doesn't always keep the plane centered well, like the panel units, so if you are considering having a tablet be your panel think it through clearly before you decide, there are limitations to what a tablet can do. It wasn't built to be a primary flight device. That said, I will still have one in my plane to supplement the real avionics. They are extremely handy to have for the sectional charts, and to be another display for weather, and easier to move around or zoom out to get a bigger picture than the panel units.

Plans: I will have an ADS-B out solution in my CCEX. Right now I am planning a single G3X, with a Garmin GPS 400W (for the certified GPS WAAS as required), a GTX 23 ES transponder (to transmit the ADS-B out), and the GDL 39 ADS-B receiver. The GDL 39 will be mounted remotely, and will have a blade antenna for the ADS-B reception mounted on the bottom, and a separate gps antenna added as well. Like I mentioned earlier, I really wish that Garmin would produce a GPS WAAS unit that is lightweight and doesn't need to be installed in the panel. I would rather put two G3X displays, but there just isn't enough panel space available.

I'll post screen captures in a separte post.

Tony