Garmin GTX 330ES not transmitting ADSB?

J

John G.

Filing Flight Plan
Joined
Sep 4, 2021
Messages
7
Display Name
Display name:
Saabflyer89
Good Afternoon,

I am new to this site and new to aircraft ownership in general. I recently purchased a Piper Cherokee with no radios and with the help and guidance, and oversite of a qualified A&P/ IA, I built a wiring harness and installed all Garmin equipment, a GMA 340, GNC 355, SL-40, and a GTX 330 ES. when we first powered everything up I had a "No ADSB" message on the transponder but after working with Garmin tech support I was able to set it up correctly. I am using the GNC 355 as the GPS, Now there is no error message and it does show the "R" in the corner of the screen. This weekend I let a friend fly the aircraft and while he was out I had my stratux box powered up just to see my airplane flying around... well I saw the 3 other aircraft in the pattern but not mine... what am I missing? it seems like everything is communicating as it should and I am free of error messages, yet I'm not seeing my plane show up.. I live across the street from the airport so I was well with in range and I was able to pick up other traffic in the area.
Thank you for any help in advance.
 
Daleandee said:
Run a Public ADS-B Performance Report Request and see what it says:

https://adsbperformance.faa.gov/PAPRRequest.aspx

Free, fast, and very easy to do.
Click to expand...

Thanks, I may plan to do this in the next week. However if I'm unable to pick up my aircraft but I can pick up others from the same spot on the ground, I would think the FAA would also be unable to pick me up, is that not the case?
 
John G. said:
However if I'm unable to pick up my aircraft but I can pick up others from the same spot on the ground, I would think the FAA would also be unable to pick me up, is that not the case?
Click to expand...

If you have a recent flight you can run the report right now and get the answer quick. Mine came back in less than 30 minutes. The report will show if it's transmitting or not. The report can also show what some of the errors are that might be causing concerns. As I said it's quick, free, and easy. Just log into the system and reference a recent flight and see what comes back.

If nothing comes back on the report then you'll know for certain that nothing is being sent. That might indicate a poor coax/antenna connection if everything else is working.

Edit: you can also contact a nearby tower (preferably when they are not too busy) and ask what they are seeing from your aircraft.
 
To the topic as it applies to me, what does it mean that I have 100% fail for SDA and SIL? They have the times and altitudes right. I don't know what's failing. It was a low day and a low flight. Would that matter?
 
Daleandee said:
If you have a recent flight you can run the report right now and get the answer quick. Mine came back in less than 30 minutes. The report will show if it's transmitting or not. The report can also show what some of the errors are that might be causing concerns. As I said it's quick, free, and easy. Just log into the system and reference a recent flight and see what comes back.

If nothing comes back on the report then you'll know for certain that nothing is being sent. That might indicate a poor coax/antenna connection if everything else is working.

Edit: you can also contact a nearby tower (preferably when they are not too busy) and ask what they are seeing from your aircraft.
Click to expand...

Thanks, I'm sorry I thought it was something you needed to submit and then go fly and they will give you a report after your flight. I did this and it was fast... although I'm not sure what all I'm looking at haha.
 
The data is there now from your last flight. Just log in and retrieve your data. It will tell you if you have any deficiencies.

I had issues with my 330ES install….it needed a software upgrade along with an upgrade to the 530W.
 
Looking though my report " thanks again Daleandee" and it looks like only the Altitude is having any kind of issue with 67% failure rate, I wonder if that is because the aircraft was doing touch and goes at a non- towered airfield. otherwise everything shows 0% fail rate. I am now wondering if Foreflight is purposely not showing my aircraft because it is assuming I'm the one flying it.... anyone else ever try to do this where someone else flies your plane and you pull it up in foreflight with a ADSB IN receiver and try to watch or follow it?
 
John G. said:
it looks like only the Altitude is having any kind of issue with 67% failure rate, I wonder if that is because the aircraft was doing touch and goes at a non- towered airfield.
Click to expand...

A test flight for Performance Report should be near to ADSB coverage, at altitude (2500" or more depending on the area), at least 30 minutes, and they ask that you only fly smooth maneuvers i.e. gentle turns, climbs and descents. As for faults found in the report see page 11 of this pdf:

https://adsbperformance.faa.gov/PAPRUsersGuide.pdf

I'm guessing the touch and goes were the problem ...
 
John G. said:
Looking though my report " thanks again Daleandee" and it looks like only the Altitude is having any kind of issue with 67% failure rate, I wonder if that is because the aircraft was doing touch and goes at a non- towered airfield. otherwise everything shows 0% fail rate. I am now wondering if Foreflight is purposely not showing my aircraft because it is assuming I'm the one flying it.... anyone else ever try to do this where someone else flies your plane and you pull it up in foreflight with a ADSB IN receiver and try to watch or follow it?
Click to expand...

If you have set your ownship ID in Stratux or Foreflight, it's not going to show it to you.
 
John G. said:
Looking though my report " thanks again Daleandee" and it looks like only the Altitude is having any kind of issue with 67% failure rate, I wonder if that is because the aircraft was doing touch and goes at a non- towered airfield. otherwise everything shows 0% fail rate. I am now wondering if Foreflight is purposely not showing my aircraft because it is assuming I'm the one flying it.... anyone else ever try to do this where someone else flies your plane and you pull it up in foreflight with a ADSB IN receiver and try to watch or follow it?
Click to expand...

Altitude errors are typically caused by a bad encoding altimeter or a bad position source which provides the geometric altitude. If you can post your report, I can analyze it. A Stratux needs to be configured with your aircraft ICAO Hex code for the transponder. ForeFlight will see the code and determine through an algorithm that the aircraft with your code is you and suppress it as a target.
 
Stewartb said:
To the topic as it applies to me, what does it mean that I have 100% fail for SDA and SIL? They have the times and altitudes right. I don't know what's failing. It was a low day and a low flight. Would that matter?
Click to expand...
This is a configuration error in your transponder. If it is a GTX330ES, you need to change the setting for GPS INTEGRITY to 1E-7.
 
You can download a PAPR user guide that explains some of the data on the report.

You should see your aircraft on your Stratux to confirm N number and position if all is working...unless you have entered your hex code in setup in which case it ignores your airplane.

If you are not near an ADS-B tower, you will need to climb up a few thousand feet or more to be seen in the system.
 
Hi guys, thanks for all the input sorry for the delayed response. I have attached the PDF report from my last flight. I know the altitude encoder is working as I have installed the optional temp probe for the 330 so I can now display density altitude on the transponder and it is working correctly. I will sit down this evening and work on adjusting the settings to 1E-7
 

Attachments

  • PAPR_20210808_AA4F94_461777964.pdf
    199.1 KB · Views: 10
I finished up my condition inspection recently. One of the things I like to do is to run an ADSB report shortly afterwards and file it in the aircraft paperwork (this one came back with all OK). I'm guessing that if there were a concern with my ADSB information that ATC would mention it ... o_O
 
John G,

The issue is not your setting for 1E-7 setting, it is fine. The issue is the position source is not providing the geometric altitude. The GNC 355 needs to be connected to the GTX 330ES via a serial port and the GNC should be set to ADS-B Out +. I think either ADS-B Out + 1 or 2 will work, but I would use the 9600 baud option. The serial port on the GTX 330 needs to be set to Remote.
 
John Collins said:
John G,

The issue is not your setting for 1E-7 setting, it is fine. The issue is the position source is not providing the geometric altitude. The GNC 355 needs to be connected to the GTX 330ES via a serial port and the GNC should be set to ADS-B Out +. I think either ADS-B Out + 1 or 2 will work, but I would use the 9600 baud option. The serial port on the GTX 330 needs to be set to Remote.
Click to expand...
Thanks, I currently have the 2 connected through the RS-232 port, is that not going to allow the proper communication between the 2?
 
The 1 vs 2 I am referring to is this:

ADS-B+ Format 1.png

This net also should not be tied into any other uses of the serial port, for example a fuel totalizer using Aviation Output or MapMx.
 
You are awesome good sir, next time you are in Tx let me know, I’ll buy you lunch!
 
You must log in or register to reply here.
Back
Top