FAA ADS-B Avionics System Check

[Radomir]

Your report is reading like you're not getting any GPS signal into the transponder. You sure Channel 2 from GPS is actually wired into the txp and you didn't mis-pin it? you're even missing Geo Alt (GPS Alt)


PS. This is not related to TIS stuff..

[jsnapp]

Originally Posted by Radomir

Your report is reading like you're not getting any GPS signal into the transponder. You sure Channel 2 from GPS is actually wired into the txp and you didn't mis-pin it? you're even missing Geo Alt (GPS Alt)


PS. This is not related to TIS stuff..

I am pretty sure. The NOADSB message goes out once the 430W acquires GPS. I was also getting TIS-B uplink on the GDL-39. If I turn on ADS-B OUT+ on port 2 the NOADSB message never goes away. I did hook a data scope up to the RS-232 port hoping that the message format was some variant of NMEA data format with extra sentences for ADSB but no luck it is a proprietary protocol that garmin will not release. Talked to Garmin and they were of know help. I may have to swap transponder and 430W to see if I can get it to go away. I hate having to bug Jim every time I try something new. I wish that the GDL-39 would let you see the raw data transmitted by the 330ES. The avionics shop I work with does not have anything either.

[Radomir]

It would be funny if this was a glitch on the FAA's side It does sound like you have everything configured properly...

The only other thing that comes to mind is a possibility of having to use a specific port (on the 430) but I have not heard of any such requirement.. Garmin would know better

PS. If you know someone with Stratus II and ForeFlight, you could try using its "own ship" feature that would show you more info and even trace logging some of the data.. I suppose you could also try to find someone with a DVB-T stick and just record "raw" data sent by the transponder as you fly around...

[GalinHdz]

Originally Posted by jsnapp

I am pretty sure. The NOADSB message goes out once the 430W acquires GPS. I was also getting TIS-B uplink on the GDL-39. If I turn on ADS-B OUT+ on port 2 the NOADSB message never goes away. I did hook a data scope up to the RS-232 port hoping that the message format was some variant of NMEA data format with extra sentences for ADSB but no luck it is a proprietary protocol that garmin will not release. Talked to Garmin and they were of know help. I may have to swap transponder and 430W to see if I can get it to go away. I hate having to bug Jim every time I try something new. I wish that the GDL-39 would let you see the raw data transmitted by the 330ES. The avionics shop I work with does not have anything either.

What output setting format do you have your G430 set to? If other than ADSB+ the data stream the FAA is receiving is non compliant. If the NOADSB message goes out with another setting (for example AVIATION) it means your transponder is not accepting the ADSB+ data format the G430 is sending which points to a software issue.

[g3xpert]

Originally Posted by jsnapp

If I turn on ADS-B OUT+ on port 2 the NOADSB message never goes away.

Hello John,

I may have missed it, but I didn't see in your troubleshooting if you turned off both RS-232 #1 (Aviation) and RS-232 #2 (ADS-B Out+) on the 430W, verified that the "No ADSB" annunciation came on, then turned just RS-232 #2 back on and verified that the "No ADSB" annunciation on the GTX turned off.

This would confirm that the connections aren't crossed and Aviation serial data is not being sent by accident to the GTX330ES. I don't know how it would behave if sent Aviation data (never tried this), but I know it wouldn't produce compliant ADS-B Out.

Thanks,
Steve

[jsnapp]

Originally Posted by g3xpert

Hello John,

I may have missed it, but I didn't see in your troubleshooting if you turned off both RS-232 #1 (Aviation) and RS-232 #2 (ADS-B Out+) on the 430W, verified that the "No ADSB" annunciation came on, then turned just RS-232 #2 back on and verified that the "No ADSB" annunciation on the GTX turned off.

This would confirm that the connections aren't crossed and Aviation serial data is not being sent by accident to the GTX330ES. I don't know how it would behave if sent Aviation data (never tried this), but I know it wouldn't produce compliant ADS-B Out.

Thanks,
Steve

Steve,
I did. I also pulled out the trransponder and connected a PC with a serial port to the RX pin of RS-232 2 and monitored it with a data scope program. I turned off the other serial port. I set it to aviation and verified that it matched the aviation format in the install manual and it did. I then changed it to ADSB-OUT+ and verified it was different. I wish I could get a document to decode the ADSBout+ format to see if it is correct.

I wish I could see the decoded data with the GDL39. I will have to play with a friends stratus this weekend and see what it shows for own ship as suggested above.

[jsnapp]

Originally Posted by g3xpert

Hello John,

I may have missed it, but I didn't see in your troubleshooting if you turned off both RS-232 #1 (Aviation) and RS-232 #2 (ADS-B Out+) on the 430W, verified that the "No ADSB" annunciation came on, then turned just RS-232 #2 back on and verified that the "No ADSB" annunciation on the GTX turned off.

This would confirm that the connections aren't crossed and Aviation serial data is not being sent by accident to the GTX330ES. I don't know how it would behave if sent Aviation data (never tried this), but I know it wouldn't produce compliant ADS-B Out.

Thanks,
Steve

I did not change it to aviation and see what the transponder did. I will have to try it with each of teh formats to see what happens to the annunciator.

[jsnapp]

I am also helping a friend look at his ADS-B report. He has a G3X feeding a 330ES and a GDL39 for ADS-B in. I know the 3GX is not fully compliant and will fail some areas. Can someone post what a report would look like for this installation? You could also email it to me at john(AT)snapp.us

[MarkW]

John,
I will send you a copy of mine. I believe my first test will show you what you need.

[jdm117]

Originally Posted by jdm117

Want to know how your ADS-B system is performing? Send an email with N-number to 9-AWA-AFS-300-ADSB-AvionicsCheck@faa.gov and request a detailed report.

Please include ADS-B transmitter & GPS make/model to save us a few emails if there are system performance issues.

FYI - I'll typically provide only one ADS-B flight report per request, especially if the report is "Green." If the report for the most recent flight happens to be "Red" I'll delve a little deeper into previous flights before replying to see if system performance (albeit bad) is consistent. If "bad" performance is consistent, only one report is sent (no point in looking at different reports that say the same thing). If performance is inconsistent, I'll likely send multiple reports in hopes you can associate performance on a given day with something you might have been doing with the aircraft and/or system at the time. That make sense?