uAvionix skyBeacon: A false sense of security?

Today my ADS-B Tailbeacon saga came to a successful conclusion. I have a clean PAPR from my flight this morning and the FAA inspector confirmed it is clean, case closed.

In summary, what I did, since it may help others:
  • Original Tailbeacon developed corrosion on its circuit board, after 2.5 years of service.
  • It failed intermittently especially in freezing temperatures.
  • The new warranty replacement Tailbeacon also failed, due to weak GPS (low NIC).
  • All other fields (tail #, squawk code, etc.) were correct. The only failure was NIC.
  • We improved the ground by wiring across the hinge from the rudder to fin. This improved things but didn't fix it.
  • We installed notch/lowpass filters on both comm radios and the ELT. This improved things but didn't fix it.
  • We replaced the panel switches to the nav light. This improved things but didn't fix it.
  • We replaced that Tailbeacon unit again, with another new warranty replacement.
  • During installation we soldered it instead of using the crimp connector. And we covered the connection with insulating shrink wrap.
  • The new Tailbeacon passed the PAPR on the very first flight and the FAA representative signed it off.
 
Glad you fixed it. Circuit corrosion seems like an inherent risk of a design that puts complex electronics out in the elements.
 
Ed Haywood said:
Glad you fixed it. Circuit corrosion seems like an inherent risk of a design that puts complex electronics out in the elements.
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Indeed. Especially when the electronics are not sealed, but open to the elements (in order for the baro sensor to work) and rely on a conformal coating. And especially for airplanes that are tied down outside, exposing it to temperature swings, moisture and UV from the sun.
 
MRC01 said:
Indeed. Especially when the electronics are not sealed, but open to the elements (in order for the baro sensor to work) and rely on a conformal coating. And especially for airplanes that are tied down outside, exposing it to temperature swings, moisture and UV from the sun.
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I always thought of it as a temporary solution to get someone through the 2020 mandate while avionics shops were slammed. In that short term role, it was a great solution in my opinion.
 
Now that it's working again, time will tell. If it starts to fail again, like the prior one did, then I'll switch to a different system with electronics inside the panel, like Garmin GL-82.
 
As the original poster to this thread, glad to hear you got it fixed :)

I still feel these wing and tail mounted uAvionics devices are way more trouble than they're worth.

Someone above called them a "temporary solution" but for north of $2,000 they should work out of the box without having to resort to all kinds of wiring tricks and gimmicks.
 
Gone Flyin said:
As the original poster to this thread, glad to hear you got it fixed :)
I still feel these wing and tail mounted uAvionics devices are way more trouble than they're worth. Someone above called them a "temporary solution" but for north of $2,000 they should work out of the box without having to resort to all kinds of wiring tricks and gimmicks.
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They actually do work out of the box, most of the time. The first one in Oct 2019 took 30 mins to install and passed the PAPR on its initial flight. A lot of other pilots have this smooth experience.

However, sometimes they don't work out of the box, or they do but the performance degrades over time. These cases can be a real pain to troubleshoot and fix. Having experienced both sides of this, the problems as I see them:
1. Inconsistent quality control: one new warranty replacement didn't work and sent us into weeks of diagnosing and testing, yet the next one was flawless, with no other changes to the airplane or installation.
2. Electronics exposed outside the airplane are likely to degrade over time, discussed above.
3. Limited virtually non-existent in-flight troubleshooting tools.
 
MRC01 said:
Indeed. Especially when the electronics are not sealed, but open to the elements (in order for the baro sensor to work) and rely on a conformal coating. And especially for airplanes that are tied down outside, exposing it to temperature swings, moisture and UV from the sun.
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Why does it need it's own baro sensor, can't it go by the transponder mode c?
 
Hindsight is 20/20…I definitely should have ordered a cover for it. Keeps sun off of it, slows temperature and humidity swings. Is that good for 5% longer life? 20%? Who knows
 
Gone Flyin said:
Glad to see so much interest in the skyBeacon and nice to know I'm not the only one to have issues with this poorly designed product. Warms my heart.

There are two factors that affect how well... and, if at all... this device will work and it seems some are confusing the two. The first is the ability for the device to "sniff" the Mode A data or what we all know as the squawk code from the power line. Interestingly, this technology was patented by Garmin and was stolen by uAvionix. It is the subject or a lawsuit that Garmin has since won a judgement against uAvionx for. You can read all about it on the web.

The 30 to 40 slider in the skybeacon app allows you to adjust the sensitivity of that sniffer. Mine is set to the middle 35 position. I had no issues with that aspect but you must make sure you solder the DC connections or use the environmental butt connectors that come in the kit. That connection has to be electrically tight.

So, the basic operation of the skybeacon is to receive GPS location data from the satellites, add in altitude data from it's own internal barometric encoder, plus the Mode A squawk code from the plane's transponder that it gets by sniffing the DC power line along with information about your plane... tail #, etc. Then send that down to the ADSB towers on the ground. To do that it has a tiny underpowered GPS receiver on the top of the unit and a dipole antenna in that white plastic wing looking piece on the bottom.

As long as you are someplace in the lower 48 of the US the ground station tower coverage should not be an issue. The stations do a good job of covering the areas we fly in. Where I am in Connecticut no matter where I go I'm being received at an ADSB tower. I know this has not been part of the problem.

The second issue and that one that will get many is the ability.... or rather the inability... for the skyBeacon to see the GPS satellites. One thing I have found is the device has undergone many changes since inception. The guts of the unit back then are not what we have in their, today.

Here is a picture of my skyBeacon mounted on the droop tip wing of my plane.

https://i.postimg.cc/YCP0CNvh/wing-tip.jpg
wing_tip.jpg


See anything that might concern you?

The skyBeacon phone app shows you something called NIC and NACp. Both of these values have to do with the GPS system. However, the app does not provide a means to monitor the satellites. How many and which it is locking on to. This feature can be found in all GPS systems. My car GPS has it. Even the Stratux low cost ADSB in device has it.

Why is it not supplied with the skyBeacon, then? How are we to know how well the device is receiving satellites if we cannot see them?

The ability to see and hold onto these GPS satellites is referred to as NIC and NACp by the FAA in their test.

In order to pass the flight test for the FAA you must have a 7 for NIC and a 9 for NACp and you must hold at least that value for most of the flight. You can have a drop out now and then but the more you drop lower than 7 and 9 the higher the percentage of failure you will incur on the test. The FAA allows some percentage but at some point they will fail you and for that you get the dreaded RED box. You have to clear the red completely or the FAA considers that flight a complete failure.

It has taken me months to get this skyBeacon to pass a single test with the FAA's PARP test program. In order for me to fly in rule airspace....that means, Mode C, A, B & C airspace and E airspace above 10,000'... I need to have a fully working ADSB out system.

Here is a portion of a sample of my flight test results up until last week.

https://i.postimg.cc/rm1wjvQr/test-2.jpg
test-2.jpg


Note the Max for NIC and NACp is 7 and 9. They barely make the needed values on a good day.

Now, after working with an electrical engineer flying buddy of mine along with another flying buddy who is an avionics engineer we came up with a potential fix for the skyBeacon. At least for my plane, that is.

Take a look at these test results from this past Saturday after the fix as applied.

https://i.postimg.cc/sXd2pV9z/test-1.jpg

test-1.jpg

I've said my peace. Now it's up to skyBeacon to take care of business and address the failings of their poor design.
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Gone Flyin said:
Had lunch with a high school friend of mine a month ago. He’s been flying for some 45 years. Suggested I get ADSB so we could, along with some other folks, fly to areas inside of Mode C around the East Coast, where we all live.

So, I picked up a uAvionix skyBeacon. That being the least expensive way to get ADSB, I felt.

Now, all this time later I still have not passed a single FAA PAPR flight test. Failure to pass the test means your system is not in compliance as far as the FAA is concerned. Hundreds of dollars in fuel and some dozen hours of flight time… all for nothing.

As it turns out, the first unit was defective. Only after many emails to tech support (they were not taking calls as they were at some aviation event) and several hours on the phone with them later on did they suggest I return the unit for a new one.

That solved one issue. The missing altitude output.

I still was failing what is called NIC and NACp on every flight. As I have since learned, this has to do with the skyBeacon’s GPS reception failing or dropping out during some portion of my flight. If it does at all, you fail the PAPR test!

With the help of my high school buddy, who happens to be a top avionics service technician, and another flying buddy who is an electrical engineer at a major defense aviation manufacturer…. We came up with the reason for the failures.

The GPS receiver in the skyBeacon is not up to the task nor is it installed
properly within the unit for adequate reception. We did come up with a potential fix and, so far, it appears to work.

Had breakfast with my former CFI. Some 38 years of flying. Also has the skyBeacon on his Cessna 172. Flys all over the coast doing these medical “angel” flights for folks who need fast transportation after an operation or procedure.

Asked him about any issues with his skyBeacon. He said, “nope, works fine”. I ran his tail number and he’s failing just as I am and he does not even know it.

Avionics shops do not want anything to do with this device. Two shops in my area said they do not install them or service them. The idea uAvionix has put forth that the average A&P can verify this is working in 10 minutes is ludicrous. They are deceiving us.

One last thought. Once installed, the ADSB must be on all the time you are flying. That is a formal rule. There is a case where a gal with 60 years of flying did a stupid stunt and her ADSB cut out. She lost her license because the FAA claims she turned off the ADSB so as not to be detected. She said she did not but has no way to prove it.

Did she or did the GPS fail on her?

My advice to anyone looking at purchasing this device to get into ADSB is DON’T!
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I've installed a few and don't like them. High failure rate, intermittent functioning
 
What happens in airspace that requires ADSB when it fails but the transponder continues working just fine? Does ATC even say anything to you about the failure?
 
Witmo said:
What happens in airspace that requires ADSB when it fails but the transponder continues working just fine? Does ATC even say anything to you about the failure?
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Depends on the ATC facility. If they are equipped to receive ADSB data and yours fails, they may ask you on the radio if your airplane is ADSB equipped. And whatever your response, they may report your tail # to the FAA who will follow up and contact you to ensure compliance.
 
Approach told one of us they had no ADSB from our plane. Checked it out; the GPS (uAvionix SkyFyx) didn’t look like it was sending data to the EchoUAT. Sent both to uAvionix; they confirmed that the GPS was bad. Turns out they’ve discontinued that one, so we replaced it with a SkyFyx-EXT. When I removed the old external GPS antenna, I dissected it - it was badly fried. Power problem? Massive ESD hit? Cheap hardware? I don’t know, but it explains why the GPS failed, or else the GPS failure explains the antenna being toasted.

A year or two ago we had to replace the EchoUAT itself. So our experience with uAvionix products hasn’t been trouble-free, but their tech support is decent and we’re still in this for about half the cost of any other ADSB OUT solution I could come up with.
 
DaleB said:
Approach told one of us they had no ADSB from our plane. Checked it out; the GPS (uAvionix SkyFyx) didn’t look like it was sending data to the EchoUAT. Sent both to uAvionix; they confirmed that the GPS was bad. Turns out they’ve discontinued that one, so we replaced it with a SkyFyx-EXT. When I removed the old external GPS antenna, I dissected it - it was badly fried. Power problem? Massive ESD hit? Cheap hardware? I don’t know, but it explains why the GPS failed, or else the GPS failure explains the antenna being toasted.

A year or two ago we had to replace the EchoUAT itself. So our experience with uAvionix products hasn’t been trouble-free, but their tech support is decent and we’re still in this for about half the cost of any other ADSB OUT solution I could come up with.
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I've used the EchoUAT with the SkyFyx-EXT for a few years now. It has been flawless. Nevertheless I bought a TailbeaconX. It hasn't made it onto the plane yet ...
 
I have a Tailbeacon and verified it worked with PAPR post-installation but never since. But I always see myself on the ADSB receiver which tells me two things:

1. The Tailbeacon is working
2. My mode-c works because the ADSB shows “VFR” which means it sees the mode c giing out squawking 1200.
 
Most apps that show ADSB-in traffic have an option to enter your own tail number so it can filter your own airplane out of the data.
 
MRC01 said:
Most apps that show ADSB-in traffic have an option to enter your own tail number so it can filter your own airplane out of the data.
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I kind of like seeing it; not only does it check the op of the transponder and the tailbeacon, it also gives me a ownship position if I lose GPS which happens occasionally. The adsb trace overlays the ownship from gps so it doesn’t clutter
 
That also works in reverse. I filter out my own tail number so when my own airplane shows up on ADS-B in I know something is wrong.
 
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