Strange Traffic Display With PowerFLARM

[aerofurb]

We've recently installed PowerFLARM in out RV-12.

We flew flight #2 & 3 today with it working (thanks to our Dutch friends assistance with the settings) and were intermittently displaying strange traffic targets - 8 targets arranged around us with no height or other info.

Sometimes they were shown as 'Traffic Advisory' targets other times as 'Non-Threats'.

And no there really wasn't anyone out there!

They weren't there the whole time and when they weren't there we were seeing normal Mode S and FLARM traffic.

I will contact Dynon and FLARM direct about it but wondered if anyone else here had seen similar.

Screenshots below show the various incorrect and correct target displays. 

 

[dynonsupport]

That's how PowerFlarm indicates a target where it doesn't know what direction it is. This will be true of all Mode C targets as they can only estimate how far away the target is, but they have no idea what direction. I notice they did show altitude on one of the 8 targets in all cases, so that sounds like a bug where they should put the altitude on all 8, not just one of them.

In the end, Dynon is showing exactly what we're sent, and this is what PowerFlarm is sending us. The same is true of them being an alert or advisory, that is in the protocol sent to us and determined by PowerFlarm.

 

[Hotscam]

I am using Powerflarm for 5 years in both my 12's and am very happy with it.
I think it is an excellent investment.
Besides looking carefully out of the window I am always suprised how many targets Powerflarm detects you never see but may be close.
The principle is that you see heading and altitude difference of planes equipped with ADSB or Flarm.
Besides this you will see pure mode C transponders but these do not transmit headings or position so Powerflarm sends a ring of targets to Skyview as it could be at any heading. It does not know the relative distance either, but this is estimated based on signal strength.
Not perfect but you are aware there is a target in the vicinity and you know an aproximate distance and exact altitude difference.
When you are alerted and know where to look up or down you usually spot them pretty easy.
There is very little ADSB here besides airliners so I am quite happy to get mode C alerts.
Actually what made be buy it were gliders that are always a surprise and in the order of 85 % are equipped with Flarm in Europe.

 

[aerofurb]

Many thanks to Dynon Support for the prompt (and on a Saturday!) response - and to Jack.

That all makes sense. For some reason, I was thinking of an actual 'ring' depicting Mode C type traffic rather than a 'ring of traffic symbols'.

We are definitely 'heads out' people but appreciate the added 'eyes' that PowerFLARM brings. We too have a lot of gliders around here and the majority now have FLARM installed.

When sorting out the settings with FLARM, they did explain the following:

FLARM Technology (we) have published a document with the full specification of the FLARM protocol. Any display manufacturer can implement this freely, so we have no control over who has implemented it, and if done correctly. However, we do have a "FLARM Compatible" certification program, under which display manufacturers can certify their display and then use the FLARM Compatible logo. Dynon has so far not done this.

You should also keep in mind that a FLARM display can be either primary or secondary. A primary display in needed in each aircraft. A secondary display is optional. The difference is that the primary display displays the required collision warnings using the FLARM protocol. This is not required by the secondary display (normally an EFIS or MFD), which is instead used to display FLARM traffic on a map as an additional FLARM feature (either via the FLARM protocol or Garmin TIS). EFIS and MFDs can however also be certified as Primary display.

Until Dynon is certified as FLARM Compatible, I would strongly recommend to install a dedicated FLARM display. This is how most of the over 30.000 aircraft installations are made.

I know that FLARM is a European thing but with in excess of 30,000 flying machines in Europe equipped with FLARM, is it possible for Dynon to make the SkyView system 100% FLARM-compatible as described above?

We don't have the space to install yet another display and we don't want to go down the route of adding to the 'eyes in' scan.

Obviously this would make full use of our chosen 'traffic' system but on the flip side, it would make SkyView even more attractive to European aircraft owners - therefore potentially increasing sales. Perhaps Dynon have looked into it and it isn't feasible - physically or financially.

It's a shame we can't have full ADS-B/TIS functionality in Europe and that isn't going to change any time soon.

 

[aerofurb]

To add another thought/question or two...

What is displayed if there are multiple Mode C targets within range?

If there are a mixture of traffic 'types' (ie Mode C, FLARM, ADS-B/Mode S ES) are all shown? Yesterday, we only seemed to pick up either FLARM/ADS-B (individual targets) or Mode C (target ring) but that may have been coincidence.

 

[JP62]

Are Dynon Support going to reply to aerofurbs very valid points?

It would be disappointing if not...