uAvionix skyBeacon: A false sense of security?

Back on topic sort of:

I have no problems with the uavioinics solutions and many are happy with the solution at our airport.

What gets me is how low power they are compared to the big xpdr solutions. When someone with a GTX345 departs or flys with I can see them well outside the puck. The wing/tailbeacon units seem to vanish after about 6-10 miles for same route and no one else in the puck.

The other one is confusion. One guy at our airport is always complaining that his ship doesn't show up on FlightAware. But all of us with GTX345 do. I tried explaining that no one in the area has a 9xxMHz pi unit running. But I think just the concept of people with little computer things feeding the flightaware machine don't register with him and thinks its the radar that generates the flightaware data. He's a great guy. But I gave up trying to explain it.

Would be interesting to see what percent of GTX345 fail and plot against the beacon installs. I would think more beacon failures but more due to owners hanging on to currently installed xpdrs and legacy wiring they don't want to touch. Where a GTX345 install rips it all out and dedicated.
 
John Spartan said:
Puhleaaaase. Martha should have lost her license permanently. Did she pay for a line drop in this story? Letting her return to the skies as they have is disgusting and would not have happened for any average Joe. And to make things even better she has absolutely no remorse. Everything she has written about it is deflection and sympathy farming. As to the ADSB?? ::shrugs::
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Actually if you got what you wanted it would be really bad for the average Joe.
 
Sinistar said:
Back on topic sort of:

I have no problems with the uavioinics solutions and many are happy with the solution at our airport.

What gets me is how low power they are compared to the big xpdr solutions. When someone with a GTX345 departs or flys with I can see them well outside the puck. The wing/tailbeacon units seem to vanish after about 6-10 miles for same route and no one else in the puck.

The other one is confusion. One guy at our airport is always complaining that his ship doesn't show up on FlightAware. But all of us with GTX345 do. I tried explaining that no one in the area has a 9xxMHz pi unit running. But I think just the concept of people with little computer things feeding the flightaware machine don't register with him and thinks its the radar that generates the flightaware data. He's a great guy. But I gave up trying to explain it.

Would be interesting to see what percent of GTX345 fail and plot against the beacon installs. I would think more beacon failures but more due to owners hanging on to currently installed xpdrs and legacy wiring they don't want to touch. Where a GTX345 install rips it all out and dedicated.
Click to expand...
Some of this is probably because the 345 is 1080 and the Tailbeacon is 978. As a consequence the Tailbeacon supports anonymous mode and the 345 doesn't.
 
I just tested my 3 planes. 1 Tail-Beacon, 1 GDL82, and 1 Lynx. All came back with good results. The tail beacon has been installed for 2 years, and had about 2000 hours put on it roughly. Hadn’t checked the report since it was installed. All 3 sit outside as well, the TB hasn’t leaked water in or anything.

Fly into controlled airspace with all 3 weekly and never get complaints.
 
I'm kinda curious about these failures with the Skybeacons. Are they "high percentage failures?" Are you doing touch & goes on the flight you submit for PAPR? Are you flying in fringe coverage areas for the given flight altittudes? If you take off and land in an out of coverage area on the flight you submitted, are you requesting specific time frame for the PAPR? Or, are you submitting the whole flight, including that time out of coverage?
 
Beacons SUCK!!!

I wish I hadn’t bought one.
Anonymous mode? Really?, got called by tail number today by a cirrus. Pretty sure I’m set to anonymous, I get back on the ground and try to verify. Beacon won’t connect to phone with numerous attempts. Finally get connected and the app stays in the screen telling you to connect and then reopen the app. On one brief moment I got to the setup screen, it showed anonymous, and then the screen went back to the one telling you how to connect.

this is my second beacon, the last one crapped out and I spent months trying to figure it out before they finally sent me a new one. AND I still get failures.
What a total POS!!!

I wish I could get my money back. I hate the thing!
 
Counterpoint.
$2K, installed myself, IA did the 337. Passed first flight, still working great 2+ years.
For a 20K Cessna 120, 2K was and is, the best option.
 
Tempting, $2000, easy install. But then it’s constant querying of the old narco mills the narco. Now it’s a transponder, $1700 sandia, and pitot static check. Beacon quits working, numerous calls to customer service, after months they finally tell me the unit is bad. But don’t send me one until AFTER I send them the defective one. Now, little over a year later it’s not working right, again.
Wish I’d gone a different route.
 
I've often wondered if these reported beacon problems were due to the aircraft electrical system serviceability since that is what the beacon system uses to communicate. There is a wire impedance requirement in the beacon install docs so if the aircraft ground plane is sub-par or there is high resistance in the affected wires it could possibly interfere with that communication pulse.
 
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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Not sure why the pics are being prevented from showing up. They are there in the edited version. Contact the administrator for this site.

I have supplied the direct links for you so see them as they are important to this reply.
 
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Gone Flyin said:
. 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.
Click to expand...
https://www.avweb.com/avionics/adsb/garmin-uavionix-resolve-patent-lawsuit/
"The exact terms of the resolution have been kept confidential."

Ain't no patent attorney, but my take on it is that Garmin claims a receiver to detect the codes broadcast by the transponder. Reading the noise signatures on the electrical system legitimately (IMO) gets uAvionix around the claims made by Garmin.
 
The problem with UAT is that they all depend on existing transponders, encoders, wiring, coax, etc. I went with a GDL82, and replaced all coax, connectors, and installed a AV74 transponder antenna. I have only signed off one Tailbeacon in the past, but it seemed to work ok. I have signed off at least 15 GDL82 units.

Not being able to view the pics in post #50, I cannot comment.

I know from my own experience that even cheap usb gps receivers and gps antennas purchased from Amazon for less than 20 dollars work pretty darn good so I would think uAvionix would/should have a decent gps antenna in their unit...maybe not ?
 
hindsight2020 said:
lulz, 10/10 for cathartic fallacy-laden emotional exfoliation. Dude even managed to somehow tie Lunken's revocation into a skybeacon wank session. Wow! I mean this stuff is gold.

Where else can I find a free collection of utterings that can deliver for my morning constitutional the way POA can. I was gonna go with the "sir this is a wendys" meme but no, this gold deserves a star. :D


aplausos-clapped.gif
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Hmmm....revocation for a single incident? Outside loop under a bridge with a dozen stalled school buses in a TFR?
John Spartan said:
Puhleaaaase. Martha should have lost her license permanently. Did she pay for a line drop in this story? Letting her return to the skies as they have is disgusting and would not have happened for any average Joe. And to make things even better she has absolutely no remorse. Everything she has written about it is deflection and sympathy farming. As to the ADSB?? ::shrugs::
Click to expand...
Yeah, she screwed the pooch - my reading of her response was her taking ownership, admitting she did it. Remorse? If it's not genuine, be honest enough not to fake it. The risk to others was at/or near zero. IMHO revocation was excessive - the safety she compromised was her own.
 
Sundancer said:
Yeah, she screwed the pooch - my reading of her response was her taking ownership, admitting she did it. Remorse? If it's not genuine, be honest enough not to fake it. The risk to others was at/or near zero. IMHO revocation was excessive - the safety she compromised was her own.
Click to expand...

I almost agree with you, if she was aware of and took care to stay clear of the uncharted YMCA zipline across the river, just upstream from her escapade.

Which, btw, has complained in the past of planes flying in the vicinity, and perhaps under the line.

But this is more thread drift.


17796475_10155070112838956_5636378102437665353_n.jpg
 
2 years with a skybeacon and GTX 327 and no issues. I get a report every couple of mounts just to be safe.
 
Larry Wilkinson said:
2 years with a skybeacon and GTX 327 and no issues. I get a report every couple of mounts just to be safe.
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Same here for 3 1/2 years and no problems. I get a report every couple of weeks though just to confirm it's still working ok.
 
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I got one of the original batch of TailBeacons just before the required date to equip, and coupled that to my old KT76A. The unit passed its initial PAPR and have had no problems at all. The price was right for purchase and the simple install.

While the unit may not put out the same signal strength as a Garmin 345, if it’s output is received by any ground station, that aircraft location is repeated to everyone in the puck. The only thought I have as to why some may be reporting an intermittent target is if the Tail/Skybeacon is not in range of a GBT, or too low in altitude, but the 978 signal is only being received directly by other interrogating aircraft possibly too far away. I guess aircraft fuselage blocking/blanking could also be a factor.
 
Same story here. My tailBeacon, self-installed under supervision just before the deadline, has worked flawlessly with my Narco AT-150.
 
The tailBeacons are a completely different design from the original skyBeacon. They are what the skyBeacon should have been had it been properly designed.

If there were no issues with the skyBeacon then why the need to create the tailBeacon?
 
Gone Flyin said:
...
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.
...
Click to expand...
I am fighting the exact same issue with my TailBeacon. Every flight, it transmits the proper tail number, squawk code, altitude gps location. None of the controllers complain about my ADS-B data. But, every performance report fails due to low quality flags (NIC & NAC). I have a GTX-327 transponder. I have an open support case with uAvionix and an FAA representative is also in the ongoing conversation.

uAvionix sent me a replacement unit. I have had it reinstalled with improved grounding (wiring across the hinge from rudder to fin). It still won't keep a GPS fix. uAvionix says it could be caused by com radios transmission and recommends installing a com radio lowpass filter like a TED 4-70. Even though the GPS signal is about 10x higher frequency than the com radios, they claim that interference still happens. And user comments on the TED 4-70 product include several people saying their com radios were jamming their GPS and it fixed this.

I would much appreciate if you could share what you did to fix your TailBeacon.
 
I asked uAvionix about the tailBeacon issue, I’ve followed your issue on pilots place. Part of the problem
, according to them, is GPS is so low power (as low as 160 dB), it easy for another signal to block it. And I’ve heard that before with antenna placement, but wouldn’t really suspect it if you’re not loosing panel GPS. To be sure your keeping NIC and NAC, you can monitor ownship in your EFB, and ensure your NIC and NAC are between 7-10 before you takeoff by monitoring it in the app. Unfortunately the beacon stops talking to the app when it detects takeoff.
 
So the uAvionix phone app shows real-time GPS position and the quality flags (NIC and NAC)? If so, that is great. It means I can ground-test uAvionix's theory that com xmit is blocking the GPS signal. Fire it up while parked on the ground, connect with the app, wait for TailBeacon to show a GPS position, wait for NIC & NAC to rise. Then click the radio to xmit and see what happens.

I don't have a panel GPS, but the GPS in my phone, tablet, and the GPS dongle in my Stratux all work flawlessly during flight. So I doubted the com xmit interference theory, but it is still worth testing. If so, that's a simple fix, just add TED 4-70 filters to the radios.
 
Installed my SkyBeacon in July of 2019. Worked flawlessly. Did the required SW update in Dec. 2019, but it bricked the unit. uAvionix promptly sent me a new one. Replacement unit installed in Jan 2020. No issues since. Just requested a report for a flight I did two weeks ago and no red boxes. So, two and a half years with no issues.

I am based within a Mode C veil so I'm sure I would have been notified if my unit wasn't working properly.

BTW, I have a Garmin GTX 327 transponder.

YMMV
 
Hmm, as I reported above, my TailBeacon has been working flawlessly, but I never bothered to install the SW update. I did not remember that update to be mandatory, but corrective of some issues people were reporting earlier.

I’m not sure this illuminates the situation others are having, but I never try to use anonymous mode. In fact, I judge proper performance of my TailBeacon, transponder (KT76A), altitude encoder, and my Stratux receiver by observing my own Tail number with altitude showing on my EFB FlyQ with traffic data turned on while still on the ground. I realize that my IPAD uses its internal GPS to give the initial round dot location symbol on the EFB map before reception of the TailBeacon augmented data. I remember that in my initial Uavionix software App setup, or was it in my FlyQ setup, I used the hex code of my aircraft to eliminate the ghost duplication of my aircraft that used to occur when simultaneously getting the GBT rebroadcast. One would think that if you turned off the selection in either the App or maybe it was FlyQ, you could then judge when and if the ghost becomes extinguished from time to time showing some failure of the gps data loop while flying. I am not sure whether that screws with the tail number representation though.
 
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Ground testing and monitoring with the phone app, under a clear unobstructed sky, with all other radios & electronics in the airplane turned off, this new TailBeacon gets a GPS fix and the NIC and NaC max out at 6 and 8 respectively. This will never pass an FAA PAPR. So it appears that the internal GPS just isn't good enough even under ideal conditions.

Also, I did notice that when I xmit on one of my radios (TKM/Michel MX385), on 121.15, the TailBeacon loses its GPS position. So that radio needs a lowpass filter. The other radio (original RT385) doesn't cause this. Yet given the GPS poor performance, the lowpass filter is necessary but not sufficient to fix this.
 
Do you have VOR whiskers?
 
Yes the plane has VOR whiskers on the tail. Note that the prior Tailbeacon worked fine. It got GPS fixes with NIC/NAC of 7/9. But it developed corrosion on its circuit board, stopped working in cold ambient temperatures, and uAvionix replaced it. This new unit is installed in the same airplane, same radios, same everything. And its GPS won't lock.
 
MRC01 said:
Yes the plane has VOR whiskers on the tail. Note that the prior Tailbeacon worked fine. It got GPS fixes with NIC/NAC of 7/9. But it developed corrosion on its circuit board, stopped working in cold ambient temperatures, and uAvionix replaced it. This new unit is installed in the same airplane, same radios, same everything. And its GPS won't lock.
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Maybe a low power problem? Check the voltage on the positive wire? Check/clean all connections in the tail.

Another Tailbeacon flyer with a GTX327 xponder, C172H/VOR wiskers. No issues since install in 2020, knock on wood. I usually request PAPR reports quarterly.
 
baboss said:
Maybe a low power problem? Check the voltage on the positive wire? Check/clean all connections in the tail. ...
Click to expand...
Good advice, but already done. We also improved the ground by wiring the rudder to the fin across the hinge. Also, all the data in the PAPR is good except GPS. No missing reports, no outages, tail number & squawk code always here.
 
jrcox19 said:
The Tailbeacon X does indeed require a controller.
Click to expand...
It speaks Capstone, so the Apollo legacy boxes, like my GNS480, support that. Have requested that Avidyne support Capstone XPDR control going forward.

Paul
 
As per uav documentation, Anonymous mode, when selected, is only active while squawking 1200.
 
The saga continues. Today I cleaned the nav light panel switch. These switches are OEM and 40+ years old. I wanted to test whether electrical conductivity through the switch was a factor. Today's PAPR still failed, but it almost passed. The failure was NIC only (everything else including NAC passed), with 8.4% fail, average of 7, min of 4.

Looks like I need to replace that switch. Is that weird? While I'm at it I might as well replace the other 4 too.
 

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Seems like the majority of failures are caused by poor gps reception. The gps antenna on the skybeacon is small, and like all gps antennas must have a good view of the sky. The droop wingtip in post #50 will definitely obscure some of the gps coverage. It would be better, IMO, if the gps antenna was able to be mounted on top of the wing. That would require a bit more install time, but would likely improve reception. I have helped install one tailbeacon that has had no issues..I think it has a better view of the sky being on the tail.

I have purchased inexpensive waas gps antennas for other projects and they all work great if mounted in a good location.
 
Doug Reid said:
Seems like the majority of failures are caused by poor gps reception. The gps antenna on the skybeacon is small, and like all gps antennas must have a good view of the sky. ... I have helped install one tailbeacon that has had no issues..I think it has a better view of the sky being on the tail. ...
Click to expand...
Mine's a TailBeacon and it's having those same GPS issues.
Another common problem is the unit not getting the proper squawk code, but this is easy to fix with the threshold setting.
 
I may be missing something, but I did not find any guidance in the installation manual for verifying that the GPS receiver was not being interfered with by Com radios. This interference is very very common, particularly on older com units. On a GPS installation, this is standard installation checkout procedure and should be done IMHO with the uAvionics unit. This is from AC 20-138D change 2:

21-1.1 Interference.
a. The lack of interference from VHF radios should be demonstrated on the completed GNSS installation by tuning each VHF transmitter to the frequencies listed below and transmitting for a period of 30 seconds while observing the signal status of each satellite being received. Degradation of individually received satellite signals below a point where navigation is no longer possible is not acceptable and will require that additional isolation measures be taken. Re-evaluation of installed VHF transceiver performance is not necessary if the filter insertion loss is 2 dB or less.
b. Evaluate the following VHF frequencies (25 kHz channels):
121.150 MHz 121.200 MHz 131.275 MHz
121.175 MHz 131.250 MHz 131.300 MHz
c. For VHF radios with 8.33 kHz channel spacing, evaluate the following additional
VHF frequencies:
121.185MHz 121.190 MHz
130.285MHz 131.290 MHz
Click to expand...

I would use ForeFlight with a portable Sentry receiver to monitor the ADS-B broadcast for the aircraft by going to More>Devices>Sentry>Status>Ownship and watch the NIC and NAC values for degradation while doing the 30 second tests of each frequency on each com unit. There should not be any failures noted during the tests of the NIC or NAC. When I had an avionics shop, about 1/3 of all installs needed to have a notch filter installed in the Com antenna coax to pass. KX155/165 and KX196/197 units and KX170B units were common problem radios. Some issues were due to the older 121.5 MHz ELT systems would re-radiate the test frequencies and cause issues. In this case, installing a newer 406 ELT would resolve the issue.
 
John Collins said:
I may be missing something, but I did not find any guidance in the installation manual for verifying that the GPS receiver was not being interfered with by Com radios. This interference is very very common, particularly on older com units. ... When I had an avionics shop, about 1/3 of all installs needed to have a notch filter installed in the Com antenna coax to pass. ...
Click to expand...
Funny you mention this. See attached, page 16. In my airplane, the MX-385 radio kills the Tailbeacon GPS when transmitting on some frequencies like 121.15. The RT-385 radio does not. I got a couple of TED 4-70 lowpass filters to install on the MX-385 and the ELT.

However, the Tailbeacon still failed for GPS quality reasons, even with the MX-385 completely removed from the panel.

PS: I just read the intro to the uAvionix GPS troubleshooting guide that I posted and it says I shouldn't distribute it publicly. So I took a screen shot of a few relevant paragraphs, I figure that falls under "fair use" as it's for non-commercial educational purposes.
upload_2023-4-30_8-3-6.png
 
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