I had previously run some quick tests feeding PowerFLARM "TIS" data to my Garmin 396. I didn't continue the evaluation because, without any indication of mode C/S targets, it wasn't going to replace my Zaon MRX.

Today I ran a ground evaluation of the new non-direction target indication provided in FLARM 3.0

I found that, when the non-directional symbol was displayed, it was very clear. However there appear to be a number of issues:

1. The altitude data is often hidden by one of the symbols that define the circle.

2. The displayed altitude is usually 100ft lower that that displayed on the FLARM screen.

3. Perhaps most concerning - the non-direction traffic symbol is never displayed if there is any other traffic (ADS-B or FLARM) being displayed, even if the non-directional target is the closest in distance and altitude.

I don't know if item 3 is a restriction in the data interface, a bug in the 396 TIS display software, or an issue with the data being transmitted by FLARM. It does make the feature essentially worthless though so I hope it can be resolved.

Display of ADS-B targets was very clear and far superior to the depiction on the PF Portable or the Butterfly display. Of course there is a lot more display area to work with. However, several times I saw an ADS-B target on the FLARM display but not on the 396 even though it was in the displayed range.

This interface has great potential for those with Garmin displays but it doesn't seem to be quite ready yet.

Andy