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18% Experimental & LSA NPE

RV6_flyer

Well Known Member
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Many of us have updated our aircraft with ADS-B out. Was reading an article and 18% of the Experimental and LSA have nonperforming emitters.

As Experimentals, the Gov't gives up lots of leeway to do things ourselves. It is great being allowed all this freedom but there is a responsibility that what we do must not only be SAFE but it must work correctly. One does not just make a change (install new equipment) and go about our merry way. We need to TEST and make sure that it works the way it is suppose to.

We as Experimental Aircraft Owner / Operators can use the FREE FAA?s Public ADS-B Performance Report Request (PAPR) website to test our ADS-B out.

IF we are going to continue to be able to use non-TSO'ed equipment in the future to meet Gov't mandated requirements to use certain air space, we need to make sure that we meet the performance requirements. Failure to meet the performance requirements (and safety) could bring more restrictions and Gov't control over the hobby we all love so much.
 
<vent> When will the FAA learn that we all use computers, not teletype machines, and that having a document full of acronyms serves no useful purpose other than to frustrate the reader? <end vent>
Does anyone know how these compliance reports are actually generated? When I was testing my ADSB-out, I would pass everything except "Air-ground". I called someone from the FAA (I forget who) and he suggested I try my test at someplace other than my home airport (LVK). I passed. He was rather vague but I think the issue is that FAA radar is somehow used to help see if the ADSB-out is working correctly, and LVK, despite being inside a mode C veil, has poor (as in non-existent) radar service at ground level. I wonder how many of these "fails" are really not failures of the ADSB-out, but failures of the FAA's system of ascertaining the quality of the ADSB data. Anyone know?
 
Document online now

There is an ADSB PAPR error report document online now. I found it when I got the same Air/Ground error. The document said to adjust the aircraft stall speed in the ADSB unit setup. Sure enough, I had somehow missed that during installation and it was set to 30 knots. Adjusted the stall setting to 60 and problem solved. My aircraft does not have a weight on gear switch tied to the ADSB so the unit assumes I am flying anytime groundspeed exceeds the stall speed set in the unit. The transponder goes to airborne mode with an increase in altitude so it was not transmitting causing the ADSB unit to sense a failure.

The error document goes through every type of error in a PAPR report and the common reasons. I just Googled ADSB PAPR report. One of the search results was the error report document.
 
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Yes. A few years back new Garmin ADS-B equipment had the default stall speed setting way too low and so most of the installs were getting air/ground errors due to the taxi to and/or from the runway exceeding that low speed. That's not really Garmin's fault but rather the installers not understanding or even fully reading the installation manual. Manual schmanual.
 
Clarity in the FAR's would help. I read them about 10 times to try and find the language of "anonymous mode not approved in ADSB rule airspace" and cant seem to find it as of a month or so ago. That will ding you a non performing emitter.
 
Clarity in the FAR's would help. I read them about 10 times to try and find the language of "anonymous mode not approved in ADSB rule airspace" and cant seem to find it as of a month or so ago. That will ding you a non performing emitter.

This is untrue. What is true is that where you need to talk to ATC they will pretty much always give you a squawk code, and a non 1200 squawk will turn anonymous mode off. OTOH you can cruise all you want between 10,500 and 17500? squawking 1200 and be in anonymous mode with the UAT.
 
This is untrue. What is true is that where you need to talk to ATC they will pretty much always give you a squawk code, and a non 1200 squawk will turn anonymous mode off. OTOH you can cruise all you want between 10,500 and 17500’ squawking 1200 and be in anonymous mode with the UAT.

If your squawking 1200 and fly under a class bravo floor or inside a mode C vail portion of ADSB rule airspace you will get a Flt Id mismatch red flag on your failed report. And eventually a friendly reminder from you know who.
 
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Well I haven't tried the things that you mentioned, but what I do know If you fly under a class bravo floor or inside a mode C vail portion of ADSB rule airspace you will get a Flt Id mismatch red flag on your failed report. And eventually a friendly reminder from you know who.

Actually, I?m based at an airport inside the mode C veil, and I and many friends fly out of here with no red flags all the time. Either your equipment is mal-functioning, or improperly set up. For starters, double check your N number and ICAO (hex) codes match.
 
If your squawking 1200 and fly under a class bravo floor or inside a mode C vail portion of ADSB rule airspace you will get a Flt Id mismatch red flag on your failed report. And eventually a friendly reminder from you know who.

Not true about the reminder. Yes, you cannot get a clean PAPR report if anonymous in engaged (only available when squawking VFR). That's why for testing purposes you either have to turn off the anonymous switch or have a discreet code squawked with ATC. The PAPR is for your own testing like immediately after installation or the recommended once a year checkup. Just because the performance report has a Flight ID mismatch doesn't mean you don't fully comply in Rule Airspace. It just means your anonymous mode works as designed and Flight ID mismatch under anonymous doesn't trigger a nastygram from Washington DC. If you have experience about a non-compliance notice arriving due to this specific anonymous squawk issue please advise.
 
I stand corrected.

I encountered some non performing emitters soon after a successful ADS-B install and after receiving a passing performance report at/and around the time I enabled and operated in anonymous mode and attributed it to that. I just confirmed that the NPE were not triggered by anonymity. It turned out to be another issue. Sorry for the confusion.
 
... 18% of the Experimental and LSA have nonperforming emitters. ...
Yeah, mine is one of them. Apparently one Immelman and a couple of loops will fail the test, presumably based on NIC.

Otherwise it's fine and has been for years.

I don't do aerobatics in "rule airspace" and cannot (and may not) disable my Mode S ES transponder at will. So I'll have to be satisfied to be in the "18% outlaws".
 
Red Tape personified...

Yessir, mine as well although I'm firmly placed in the 57% of registered GA aircraft yet to install ADSB-Out. I spend 100% of my workday operating in ADSB-Out airspace and have no desire to do the same on my own nickel.
Interestingly enough, I have "experimented" with several Class B excursions and so far ATC has granted me entry each time with Mode C/Non ADSB, so far...

Besides, like you, most of my RV air-time is spent in unusual (usual to me) attitudes far from ADSB-Out airspace. :)

V/R
Smokey

"Absolute Power corrupts, absolutely."
Sir John Acton
 
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