Passing an ADS-B performance report with the skyBeacon or tailBeacon

I have a tailBeacon installed on my aircraft, and at any given time, I can get anything to pass the performance report, but not everything at the same time.
I've adjusted the transponder threshold, and that took care of the most prevalent problem .. Mode 3A failure. Now I get the occasional NIC or Flight ID failure. I cannot explain Flight ID failures, but the NIC failure is GPS coverage. Looking at the uAvionix manuals, it looks like the NIC failure often happens from too short of a time between powerup and takeoff. So, I am wondering ..

For those with the tailBeacon or skyBeacon:

1. Are you always getting passing ADS-B performance reports? Or, are you getting some failures occasionally? If you believe that you're getting good performance reports always, how often are you checking?

2. How long are you on the ground before takeoff? I would say it's about ten minutes or so on average for me.

Thanks!

I have a wingtip TSO SkyBeacon on my PA-28. I received a satisfactory performance report and used it to claim my second round rebate. A good report depends on being in range of a ground station. Pick where you run your test.

Tower at my base airport has reported my ADS-B as inop soon after takeoff but they later admitted they don't have good coverage at low altitude. My SkyBeacon allows me to legally fly in the Phoenix mode C area and that's good enough for me. I don't keep testing it to see if I can get a bad report.

Anecdotally, my Garmin GTX 345R seems to have better area coverage when looking at unofficial ADS-B tracking sites.

PA-28 time on ground probably at least 10 minutes. Usually shorter in the FX-3 with GTX 345R. ADS-B exchange shows my FX-3 at the hangar at power-up and for taxi and takeoff. It may not show the PA-28 with SkyBeacon until well into takeoff roll. GTX-345R also shows my return to the hangar and the turn to position for pulling in. SkyBeacon usually drops out soon after touchdown.

Not much doubt in my mind that GTX 345R has better performance but the difference is no handicap to operating the PA-28.

Edit to add - I should point out that SkyBeacon is UAT and GTX 345 is Mode S ES. I have not compared SkyBeacon with other UAT systems.

Thanks.

The skyBeacon & Garmin GTX-345 definitely won’t get the same coverage. The skyBeacon transmits over 978, whereas the 345 is 1090. So that likely explains the apparent significant coverage difference that you are seeing, especially on the ground.

SPX said:

Thanks.

The SkyBeacon & Garmin GTX-345 definitely won’t get the same coverage. The skyBeacon transmits over 978, whereas the 345 is 1090. So that likely explains the apparent significant coverage difference that you are seeing, especially on the ground.

Click to expand...

Additionally, the Skybeacon and other UAT solutions typically broadcast at roughly 5 watts power. Your 1090-ES solutions that are broadcast by the transponder are typically broadcasting at 70 or more watts. Big difference in broadcast range. That's one of the reasons ATC may tell you your ADS-B is inop and why those of us flying with UAT solutions often times don't show up on the commercial flight tracker sites. At more than 15 - 20 miles, they may not receive your signal, especially if you are at a low altitude. I find that air-to-air, I usually don't see other aircraft with UAT transmitters until they are within 20 miles of me, while they guys with 1090-ES are visible a couple of hundred miles away.

The uAvionix UAT solutions depend on your transponder being in radar range as it reads the reply of your transponder to an interrogation. In my area of Northern AR, none of the uAvionix unit units will get a clean PAPR report if the flight is done locally. You have to go do your check flight near a ground based radar to trigger the transponder. Of course if you look at the ADS-B requirements, any place ADS-B is required, also has pretty good radar coverage. So while those show up as failures on the PAPR reports, those failures go away when you are in ADS-B required air space.

I have yet to see an installation of the EchoUAT or wingtip or tail light SkyBeacon that didn't benefit from having the transponder sensitivity adjusted. It seems that they come set just a bit too sensitive and that causes issues.

This probably reads as a criticism of the uAvionix units. It's not. I own 3 of the EchoUAT units mounted in my planes and really like them. But it is good to be aware of their limitations and to understand that some of the failures are often times not failures. Sometimes it can be difficult to recognize.

As for the Original Post, it sounds like the built in GPS is not acquiring satellites properly, or is losing them. An occasional hiccup there can happen, especially if you are doing a lot of maneuvering (like student training). I wouldn't worry about it flagging that red in the PAPR as long as the failure percentage is still low. But if it is a consistent problem, your unit may need replacement.

-Cub Builder

My first SkyBeacon passed initial PAPR reports, but required that I go to 11,000 feet or greater for adequate coverage. Several months later, I received a call from, gulp, Washington, DC. A very polite FAA gent informed me that my beacon was consistently transmitting bad data. He suggested I contact uAvionix, and stated that in the meantime, my beacon was going to be “turned off” in the FAA’s system (I didn’t know they could do so), so DO NOT fly in rule airspace.

I called uAvionix and worked through trouble shooting with their techs, to no avail. They sent me a new unit. I flew two flights for PAPR reports, which passed with a couple of “failures”. I called the FAA gent, who looked at my data and said “Good to go”. There are some functions in those PAPR reports that are due as others have noted above, to issues the FAA is not concerned with, the primary one being just outside good ground coverage.

The FAA informed me my beacon was back in service. Have heard nothing since from them, but some PAPR reports exhibit occasional red flags.

I was very impressed with the gentleman from FAA on this. He was clearly interested in getting my beacon functional, as and not the least threatening.

It was kinda spooky to me that the FAA is actually monitoring these things. For perspective, the nearest rule airspace is 120 miles from me, and I had been nowhere near it during this period.

MTV

Also want to mention, in case it's not obvious that you should turn off the anonymous mode until you've successfully gotten a passing PAPR.

I am inside a mode C veil and we have good ground based adsb station coverage here where I'm at so I passed first time. We've installed 3 additional of the sky beacon units on planes that I work with (2 pawnees and a super-cub). Initial quality was poor - 2 of the 3 units brok within the first 3 years of install, but uAvionix replaced them for a reasonable repair fee. However all 3 of those in addition to my own personal airplane all passed the PAPR pretty easily.

Thanks for the replies. I flew again yesterday. 20 minute flight, and everything was perfect but NIC, which had 15 seconds of fail. :-(

I installed a Tailbeacon on my C180 back in October 2019.
My first flight generated a failure--
I can't remember which field but uAvionix told me it was probably due to not enough txp warm-up time.
Only time that ever happened.
I had another failure later when I installed my spare transponder (old Narco AT150),
I don't remember which field this one was either.
I had to turn up the "gain" (or whatever they call it) on the tailbeacon app,
then it worked just fine.
FWIW I usually have it set on "anonymous",
but once every month or two I de-select anonymous
and get a PAPR test to make sure it's still working as it should.
Other than those two initial failures,
it's always worked just fine.

Thanks for the replies; I will try again next week. The only failure that I have now is NIC for 15 seconds. So, I am getting closer, but not there yet.