ADS-B Out flight check failed

[RVDan]

I recently upgraded my SV system to the SV-GPS-2020.  The SW is upgraded to 14.0.1 and the transponder SW was upgraded.  With the aircraft outside and the GPS receiving satellites, the transponder page in setup shows everything good.

Initiated a flight from an airport in marginal ADS-B coverage (KCBE) direct to one with ADS-B coverage to the ground (KFDK).  The flight was 36 minutes and straight line at 5500 ft MSL except for a 360 degree, 30 degree banked turn left then right.

The results back for the FAA were good except for NACp which showed GPS out of limits for 2.7% of the flight.  Need to solve this.  There are no drops shown for the messages, just the GPS position accuracy exceeding limits. 

Any suggestions?

 

[dynonsupport]

Dan:

If there's been less than 1 hour of SkyView operation since this issue, can you send us a Dynon Diagnostic File?

I recently upgraded my SV system to the SV-GPS-2020.  The SW is upgraded to 14.0.1 and the transponder SW was upgraded.  With the aircraft outside and the GPS receiving satellites, the transponder page in setup shows everything good.

Initiated a flight from an airport in marginal ADS-B coverage (KCBE) direct to one with ADS-B coverage to the ground (KFDK).  The flight was 36 minutes and straight line at 5500 ft MSL except for a 306 degree, 30 degree banked turn left then right.

The results back for the FAA were good except for NACp which showed GPS out of limits for 2.7% of the flight.  Need to solve this.  There are no drops shown for the messages, just the GPS position accuracy exceeding limits. 

Any suggestions?

 

[RVDan]

There has been no flight time since the test flight. I'll download the diagnostic file and submit along with the FAA report. I believe that I have access to the detailed ADS-B track data from the FAA and may check that also.

 

[Leaph737]

I have the same issue going on with my system as well.....

 

[jabarr]

I received the same results for NIC and NACp.   Virtually identical numbers as above post.  A recent flight showed all OK. No changes between flights.

 

[Dynon]

Can any of you that are seeing instances of this send your reports (we may also want diagnostic logs if you can pull one) and send them to us at support at dynonavionics.com so that we can look into this more closely? Include a link to this thread too.

 

[jabarr]

Dynon has a very recent diagnostic file sent for case #223031 however a recent flight was reported as working fine. No changes were made between the bad and good reports.

 

[Leaph737]

jabbar where is the location of your GPS antenna?

 

[jabarr]

On top of fuselage behind canopy. (RV7)

 

[RVDan]

There has been no flight time since the test flight.  I'll download the diagnostic file and submit along with the FAA report.

I uploaded my diagnostic file from last week for N199EC.  Antenna location- RV-6 1 ft aft of the canopy on fuselage centerline (top).  This location shouldn't be shadowed by wing or tail surfaces. 

 

[Leaph737]

I spoke with Mike H yesterday and he is escalating our issue up the chain. I am thinking this might be a software issue but will await Dynon's next step.

 

[airguy]

How are you receiving this report, do you just request an ADSB report from ATC while flying, or do you need something else?

 

[Leaph737]

You send an email to the FAA requesting it.

 

[airguy]

Dynon - I got my report back from the FAA and it shows the same failures as above. Could this be caused by one screen rebooting due to the V14.0 bug and temporarily disrupting ADSB?

 

[dynonsupport]

I spoke with Mike H yesterday and he is escalating our issue up the chain. I am thinking this might be a software issue but will await Dynon's next step.

OK - we are looking at some of the logs now and have detailed FAA radar data of a particular flight. The good news is that in all of the cases we looked at, the GPS is performing very well and is NOT the source of the NIC and NACp values of 0. Evidence to date indicates something between SkyView and the transponder, inside the transponder, or the transponder and the FAA radar site is creating the occasional values of 0 when we would expect something more like 8. This is where we are focusing our efforts. The GPS side of the equation seems to be fine right now so please don't be thinking about drilling new holes in your bird for the time being.

We will post again when we find out more information.

 

[RVDan]

Thanks for the update.

 

[RV711AC]

On this subject, I passed the flight check when I first installed the Dynon transponder and upgraded the FW in my 430W. There have been several FW updates to Skyview since. When is it prudent to repeat the flight check?

 

[swatson999]

On this subject, I passed the flight check when I first installed the Dynon transponder and upgraded the FW in my 430W. There have been several FW updates to Skyview since. When is it prudent to repeat the flight check?

If it were me, in this case...

January of 2020.

 

[acepilot59]

I failed my FAA flight test of my ADSB and GPS software yesterday.  I had recently up dated my SkyView software to the 14.0.1 software and changed the SV-GPS-250 software to transmit SDA/SDL=1.
The error message that I got from the FAA is significantly different than the others posted. See attached.

 

[n456ts]

SV-GPS-250 software to transmit SDA/SDL=1.

The SV-GPS-250 doesn't meet 91.227. You will have to replace it with the SV-GPS-2020 to meet 91.227. The new software update just allows you to get traffic with your current setup until December 31, 2019.