Got me a certified letter from the FAA the other day stating that my new GTX 345 had errors transmitting my ID and there were a lot of air on ground errors. The man from the FAA stated it was a software issue with Garmin. I explained my type of flying involved lots of very low level flying evaluating off airport landing sites and that was probably giving the air on ground errors. He asked me if my cub had a squat switch. I guess my problem is I have an ADS-b switch but that cant be avoided as I fly out of class C. Anyone with similar issues

Yep....flew the first flight last Friday after install and the report was
all OK except for the air/ground report in red. Will fly some more and
check again. May be a location problem on transponder transmission
when taxing.
Pukingdawg

The first qualification flight I did I was told not to turn on the transponder until I had taxied to the runway and then to turn it off after exitiing the runway in order to prevent an air on ground error or else you can taxi very slowly. Passed the qualification flight first try. I normally taxi very slow in order not to chew up the bushwheels. So now I don't know if the error is from normal taxi or off airport ops. FAA guy says air on ground errors are common and they may in the future allow more errors before you qualify for a performance fail. Like me if you get a performance fail after successful installation you get a certified letter saying you got to fix it or they will block all FIS-B weather and traffic info. I also had emit ID errors for a total of 2 seconds on a 3 hour flight which he was more concerned about. FAA guy says it is a software issue with garmin but I have not contacted garmin yet. There is a service alert for updated version 2.12 on the Garmin website. My installation was 6 months ago and version 2.12 came out January this year. It appears that version 2.12 addresses air on ground errors but not necessarily the emit ID error.

Had 345 installed in Denver (September 2017) on my T210; did not do the in-flight certs. Later, late Dec., flew VFR with flight following to Albuquerque. On VFR/flight following return trip home to EIK (Denver area) we asked center about ADS-B; they checked and told us everything working correctly-no issues.

From what my controller buddy tells me ATC generally sees ADS-b and non equipped planes the same unless they chose to throw some switch to tell the difference. The ID emit problems and air on ground errors are not something they would ever see. It appears that FAA computers are monitoring performance of your equipment every second you are flying. With reduced separation as the goal for the future they must be monitoring for accuracy and reliability of participants. It appears they will reject you from participating in reduced separation if your equipment is not up to snuff. The info I got said they would block FIS-B weather and traffic and they would treat you as mode C transponder equipped. When 2020 comes this may mean denied entry to airspace for which ADS-B is required.

flyingjack wrote:Had 345 installed in Denver (September 2017) on my T210; did not do the in-flight certs. Later, late Dec., flew VFR with flight following to Albuquerque. On VFR/flight following return trip home to EIK (Denver area) we asked center about ADS-B; they checked and told us everything working correctly-no issues.

Unfortunately, asking ATC doesn't accomplish very much. The only way to get an official check is to use the FAA's ADS-B performance compliance system, which is so easy to use that it's worth doing periodically to make sure something hasn't happened to screw up the system. https://adsbperformance.faa.gov/PAPRRequest.aspx Fill in the blanks, submit it, and in less than 30 minutes, you'll have a 6 page report telling you if there's a problem.

BTW, Garmin isn't the only one having a problem with air/ground issues. The original KT74 STC relied on whatever authorized position source to provide proper ground indications, in the form of GPS speed. But because it didn't work very well, the STC was modified to require either a squat switch or an airspeed switch. Mine has the airspeed switch, which is calibrated to switch the signal when the airspeed drops below 40 Knots.

Cary

Just got my AOPA Pilot magazine and there is an article all about what I am asking about. The article is titled Bad Data, No Service. The article goes on to explain that almost 10 percent of 35000 equipped GA aircraft are non performing and 22 percent of 13000 experimental, light sport and air carrier installations are non performing. Thought I would install early to avoid the 2020 deadline rush (had to wait 6 months as it was) but maybe being late to the game will give them time to work out the bugs. I am tired of being the beta site for new technology. Cant wait to see how much more it will cost than the 5 large I've already spent.

I've got the Garmin 335. I already had ADS-B in and didn't want to pay Garmin extra for that when I got ADS-B out. I don't have any air on ground report issues, but the traffic notification often shows a ghost plane right on top of me. It really freaked me out the first couple of times it happened. It seems some confusion in the software reports my own plane as a target I need to avoid. It usually happens without any identification of approaching traffic. Now when the first indication I get is the ghost ship right on top of me I ignore it.

I think it was Flyhound who told me about his experience doing the performance check flight to get his $500 ADS-B rebate:
FAA (or whoever) kicked the rebate application back, turned out that for some reason his aircraft registration did not include the year of manufacture. That red-tagged it, even though his gizmo worked just fine.
A phone call to correct their database and all was well.
So "performance issues" ( I always think of Robert Downey's line in the Avengers movie when I read that)
might not necessarily be gizmo-related.