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An Interesting point about EAB and ADSB

Peterk

Well Known Member
ADSB for homebuilts?

After reading the recent ADSB group buy discussion I was very interested and began to think seriously about the financial investment. Today I read J. Mac McClellan's article on current FAA rules concerning ADSB. He is under the impression that experimentals are still out in the cold because of the TYPE requirement. We have no TYPE. He is recommending that we (the experimental community) hold off until the issue is settled.

Thoughts?

This is Mac's quotation:
Under its number one priority to keep ADS-B rules strict the FAA apparently forgot about homebuilts and other experimental airplanes. The rules require an STC (supplemental TYPE certificate) or TC (TYPE certificate). I capitalized type because that?s what is missing in an experimental. By its very existence an experimental aircraft has no type certificate. It?s a one-off, no matter if homebuilt, prototype, exhibition or developmental.
 
My thoughts... I'm not sure you really wanna take that position with the feds, they could easily come back and require a "Field Approval" for every aircraft make and model like is currently required on certified aircraft that are not covered by an STC (every experimental is a different make so every one would required a seperate approval), trust me you don't want to go down that road :eek:

The approval guidelines are covered in AC 20-165A, the reg is pretty clear:

§91.225 Automatic Dependent Surveillance-Broadcast (ADS-B) Out equipment and use.
(a) After January 1, 2020, and unless otherwise authorized by ATC, no person may operate an aircraft in Class A airspace unless the aircraft has equipment installed that—

(1) Meets the requirements in TSO-C166b, Extended Squitter Automatic Dependent Surveillance-Broadcast (ADS-B) and Traffic Information Service-Broadcast (TIS-B) Equipment Operating on the Radio Frequency of 1090 Megahertz (MHz); and

(2) Meets the requirements of §91.227.

(b) After January 1, 2020, and unless otherwise authorized by ATC, no person may operate an aircraft below 18,000 feet MSL and in airspace described in paragraph (d) of this section unless the aircraft has equipment installed that—

(1) Meets the requirements in—

(i) TSO-C166b; or

(ii) TSO-C154c, Universal Access Transceiver (UAT) Automatic Dependent Surveillance-Broadcast (ADS-B) Equipment Operating on the Frequency of 978 MHz;

(2) Meets the requirements of §91.227.
 
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Doesn't it seem bizarre that the EAA would publish at article, written by an EAA employee, that confidently announces experimental aircraft are not allowed to install ADSB equipment?????
 
Well, I'm not taking mine out, and so far the FAA seems perfectly fine with it, even providing a performance report for my aircraft. :)

I concur that it seems it's an attempt to gin up a controversy where none exists.
 
My thoughts... I'm not sure you really wanna take that position with the feds, they could easily come back and require a "Field Approval" for every aircraft make and model like is currently required on certified aircraft that are not covered by an STC (every experimental is a different make so every one would required a seperate approval), trust me you don't want to go down that road :eek:

The approval guidelines are covered in AC 20-165A, the reg is pretty clear:

?91.225 Automatic Dependent Surveillance-Broadcast (ADS-B) Out equipment and use.
(a) After January 1, 2020, and unless otherwise authorized by ATC, no person may operate an aircraft in Class A airspace unless the aircraft has equipment installed that?

(1) Meets the requirements in TSO-C166b, Extended Squitter Automatic Dependent Surveillance-Broadcast (ADS-B) and Traffic Information Service-Broadcast (TIS-B) Equipment Operating on the Radio Frequency of 1090 Megahertz (MHz); and

(2) Meets the requirements of ?91.227.

(b) After January 1, 2020, and unless otherwise authorized by ATC, no person may operate an aircraft below 18,000 feet MSL and in airspace described in paragraph (d) of this section unless the aircraft has equipment installed that?

(1) Meets the requirements in?

(i) TSO-C166b; or

(ii) TSO-C154c, Universal Access Transceiver (UAT) Automatic Dependent Surveillance-Broadcast (ADS-B) Equipment Operating on the Frequency of 978 MHz;

(2) Meets the requirements of ?91.227.

So I don't see this:

The rules require an STC (supplemental TYPE certificate) or TC (TYPE certificate).

anwhere in there. Additionally, the AC has a clause that specifically states it is NOT mandatory.

More from the blog:

Some builders are installing ADS-B equipment that is potentially certifiable and believe they have met the rule. But they haven?t. The rule requires flight manual supplements, operating restrictions, a performance test and other approved paperwork and there is no way for a builder to get there.

If he's citing the AC as a "rule" for this analysis, then see the above statement where the AC itself says it is not mandatory.

The "rule" is the FAR as cited above, not the AC.


I think his position that you can't install an ADS-B receiver on an EAB is hogwash. :)
 
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What am I missing?

How is this any different from any other piece of equipment we install? I don't need an STC or 337 for a new radio or GPS, why would I need one for this?
 
"ADS-B is bad" perspective

I'm frankly skeptical about the completeness of this story.

I first noticed when Mr. McClellan came to the"Sport Aviation" masthead, and have since monitored"AOPA Pilot" as well;"ADS-B = bad" is a drumbeat.

Whether cast as too expensive, not fully implemented, not usable for most, or not useful, the message consistently focuses on the negative, rather than the positive aspects of implementation.

"If you have a homebuilt or LSA what can you do? The only sensible answer is to wait on the FAA. If you buy and install equipment that you think can be approved in the future you may guess wrong. If you have an airplane delivered from the factory with a fully integrated avionics system you?re stuck waiting, too. So the mixed message from the FAA is the standard hurry up and wait..."​

Rather than "wait on the FAA" I enjoy the benefits of my ADS-B (in) today:
in flight weather!
METAR's beyond radio range!
traffic I never saw before (even if an incomplete picture)

I also continue my plan for an integrated -in and -out system for the future.
 
Mac is "confused" ;) but that shouldn't come as a surprise... (eg. you don't get an STC for an experimental to equip it for IFR flying yet you're perfectly legal when using correct/approved equipment -- and ADS-B story is/will be the same for experimentals).
 
Doesn't it seem bizarre that the EAA would publish at article, written by an EAA employee, that confidently announces experimental aircraft are not allowed to install ADSB equipment?????

In a perfect world - yes it would be bizarre... but we're far from perfect world. EAA hiring a guy who's probably never seen an experimental aircraft as the editor of the magazine shows you how far from perfect world we are.
 
Actually, the rules (91.225 and 91.227) do not require STC or TC. They require certain TSO's for the equipment and are otherwise performance based. The only conondrum for the FAA is to determine policy on how you as that aircraft owner/operator demonstrate that your system meets the requirements. If you have equipment meeting the TSO's, you get 95% of the way there. The rest can be verified easily with ramp test equipment your favorite shop should have already or soon. A final verification could be the FAA report you can get by email, once you fly the aircraft and are observed by the ground system.

For part 23 airplanes, field approval, which is a far cry from an STC or TC approval, has always been on the table, the FAA just has to decide to go forward with this. As I understand it, a good number of the early instalaltions have not passed muster when observed by the ground stations. They either have been installed incorrectly or configured incorrectly. Perhaps a good reason for the FAA to be slow to ease the policy.

It is not rules that must change, but policy, which often happens as pressure mounts and deadlines come knocking.
 
Even better was Mac's article in the most recent Sport Aviation calling into question the need for highly accurate ADS-B position reporting for VFR traffic where the rule of the sky is (and will remain) "see and avoid".

If someone at the FAA agrees with him, and he does make a good argument, then maybe, just maybe, we will be able to use a VFR capable GPS as long as we stay out of the clouds.
 
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Perhaps this thread should be combined with the ADS-B group buy one.

Who can do that? If it can be done, yes it should.

I think its important that we get to the bottom of this rather than simply state our preferences. Where is Mac getting his info? What is he basing this on? Surely there is an ADSB manufacturer or aviation legal individual up to date on the regs that can straighten this out.

Mac states, with confidence, that ADSB equip CANNOT be installed in experimentals. Mac works for the the EAA. What if Mac is correct? Wouldn't this be a good time for someone who knows the answer to step forward? Before we all go out and spend $4,000 plus?
 
If someone at the FAA agrees with him, and he does make a good argument, then maybe, just maybe, we will be able to use a VFR capable GPS as long as we stay out of the clouds.

I have ADS-B "in" (actually not quite yet - I need to get that GDL-39 Stein wants me to have) with a Garmin GTX-23ES and my G3X GPS providing the GPS feed. The G3X is "WAAS accurate" but not "WAAS certified" so I will not be "2020 Rule" legal when I add the GDL-39, as I understand it. The Feds really need to relax the GPS requirement because those of us in this position will be required to spend $2,000-$6000 or more to get the required GPS with no increase in functionality or accuracy.
 
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Doesn't it seem bizarre that the EAA would publish at article, written by an EAA employee, that confidently announces experimental aircraft are not allowed to install ADSB equipment?????

Agreed, the article is flawed. Sure would have been nice if he included the references from which he is basing his conclusions. Mac demonstrates once again he really does not understand the experimental world. He clearly does not know the difference between S-LSA and E-LSA.
 
Agreed, the article is flawed. Sure would have been nice if he included the references from which he is basing his conclusions. Mac demonstrates once again he really does not understand the experimental world. He clearly does not know the difference between S-LSA and E-LSA.

It would have been even nicer if the article was correct in regards to EABs, at least, seeing as the "E" in "EAA" used to stand for "Experimental".

So how many people reading that blog are now a) misinformed about what they can install on their EXPERIMENTAL amateur-built planes, and b) p*ssed off at the FAA based on a wrong understanding of the rules? Just go read the comments over on the blog...virtually every one is negative, based on *faulty information*.

Couple that with the constant barrage of "ADS-B is all bad, all the time!" from this guy (who represents EAA) and what a great way for EAA to foster a good working relationship with the FAA. Not.

Mac should stick to writing articles on how cool it is to fly the latest Gulfstream. For Flying magazine.

What was EAA thinking in hiring him for Sport Aviation?
 
I must be missing something related to the context of some peoples posts, because I didn't read Mac's article to say you technically can't currently install ADS-B equipment in an E-AB aircraft (or many others that he mentioned).

But that you can't currently do an installation that will meet the requirements of the TSO (as currently written) at the beginning of 2020, and be allowed to fly in airspace that will require it.
I believe this may be somewhat true (depending on what requirements the FAA decides to set, to prove that a particular aircraft meets the TSO requirements).

I do agree that a lot of the other details in the blog post are not on the mark.
 
I must be missing something related to the context of some peoples posts, because I didn't read Mac's article to say you technically can't currently install ADS-B equipment in an E-AB aircraft (or many others that he mentioned).

But that you can't currently do an installation that will meet the requirements of the TSO (as currently written) at the beginning of 2020, and be allowed to fly in airspace that will require it.
I believe this may be somewhat true (depending on what requirements the FAA decides to set, to prove that a particular aircraft meets the TSO requirements).

I do agree that a lot of the other details in the blog post are not on the mark.

First couple of paragraphs:

So you’re ready to take the plunge and install equipment that meets FAR 91.225 and 91.227 requiring ADS-B “out” for flight in regulated airspace after the end of 2019. Can you do that?...
If you built your own airplane, or bought an E-AB that someone else built, the answer is no.

So whether you read this as a statement that the actual installation is not allowed (wrong) or whether the installation will not allow flight under the FARs post-2020 (also wrong), he's wrong.

I believe that his "logic" is probably based on reading the AC as a requirement, when it clearly states that it is not.

As long as my equipment complies with the appropriate TSOs, and meets FAR 91.227 (which is a bunch of performance specs), then it will be legal under 91.225 to fly with it.

Let's look at where he's gone wrong:

Under its number one priority to keep ADS-B rules strict the FAA apparently forgot about homebuilts and other experimental airplanes. The rules require an STC (supplemental TYPE certificate) or TC (TYPE certificate).

Really? Which rule? Show us the rule that says this, please. (ETA: I get that "the rules" in general, the FARs, require STCs for type certified planes. Not talking about those here, though. I don't see any *ADS-B-specific* rule that says an ADS-B installation has to have an STC. Maybe I'm wrong, but I read 91.225, 91.227, the AC and the TSOs, and I don't see such a rule. I think he's asserting that the rule for STCs necessarily applies universally, and thus, to ADS-B installations; that clearly is not the case for E-ABs).

No such "rule" exists.

Maybe ADS-B in a homebuilt could be certified by an FAA field approval where an FAA office approves modification of a specific airplane. But that doesn’t seem to work for homebuilts. It is the builder who is the “approved” modifier and equipment installer. A field approval normally is granted to an individual based on work performed on other airplanes of the same type. There’s that word again.

What on earth is he talking about? This is gibberish.

Some builders are installing ADS-B equipment that is potentially certifiable and believe they have met the rule. But they haven’t.

Really? Why not? If all of my equipment meets the TSOs, and performs in accordance with 91.227, which rule is being violated? None.

The rule requires flight manual supplements, operating restrictions, a performance test and other approved paperwork

Again, which "rule" is that? A cite to the AC is incorrect, as that is *advisory*, and itself states

This AC is not mandatory and does not constitute a regulation.

Well, at least he got this part right:

By its very existence an experimental aircraft has no type certificate.
 
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What I find peculiar is given that the EAA (and AOPA) is fairly tight with big shots at the FAA, why would you write a "maybe this/maybe that" article without getting some attribution from the FAA? But maybe that's just the journalist talking.

I generally think in an article like that, it's a good idea that there be at least SOME quotation marks with a bunch of words in between.

At the very least, if you're not going to talk to the FAA, have some quotes from your own governmental affairs guy to at least give the appearance EAA is on the case and FAA is aware of the situation.

I wouldn't even bother marking it up with the red pencil if a reporter had handed this in to me. I'd just throw it back.
 
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I am probably missing something so please correct me, but is the current state not precisely what we want and matches the past president well?

E.g. currently (in most places/airplanes) we need a transponder that meets TSO (doesn't need to be TSOed). The way we prove that is that we say so.

I would hope the same applies for ADS-B which I think is the current state of affairs. As long as our equipment meets TSO we meet all regulations required. Done.

The worst thing we can do is ask the FAA for an AC for us... . It can only get more complicated then that.
 
He's retiring in April. Hopefully EAA will find a replacement with better ties to EAB (Mac had none) and who will do the appropriate amount of fact finding before publishing stories reminiscent of Chicken Little in his blog.

Before you guys dismiss this as Chicken Little story you may want to read AC 20-165A and AC 90-114.
 
Before you guys dismiss this as Chicken Little story you may want to read AC 20-165A and AC 90-114.

Not my particular area of expertise, but doesn't Chapter 1-2 of AC 20-165A explicitly say that it applies to aircraft with Type Certificates. (And therefore NOT to EAB's)?

http://www.faa.gov/documentLibrary/media/Advisory_Circular/AC 20-165A.pdf

AC 90-114 discusses performance requirements for ADS-B out, but nowhere can I find anything that says Bubba off the street is prohibited from installing a system in my EAB airplane. The requirement is that the finished install meet certain performance measures.

http://www.faa.gov/documentLibrary/media/Advisory_Circular/AC 90-114.pdf
 
Before you guys dismiss this as Chicken Little story you may want to read AC 20-165A and AC 90-114.

I've read them both. I see nothing in either one to support McClellan's position on ADS-B in EABs.

Both of them further state that they are not mandatory.
 
E.g. currently (in most places/airplanes) we need a transponder that meets TSO (doesn't need to be TSOed). The way we prove that is that we say so.

And the 24-month static/XPDR test by a certified inspector/test facility/whatever, as well as the specs from the manufacturer which document compliance with the TSO, right?
 
And the 24-month static/XPDR test by a certified inspector/test facility/whatever, as well as the specs from the manufacturer which document compliance with the TSO, right?

The static/XPDR test has nothing to do with the installation.

Using the documents of the manufacturer is a convenient and generally cost effective way to show that you comply with the TSO but it's not required as far as I can tell.
 
The static/XPDR test has nothing to do with the installation.

Using the documents of the manufacturer is a convenient and generally cost effective way to show that you comply with the TSO but it's not required as far as I can tell.

True enough on the TSO for manufacture...one could build one's own XPDR and test it to the TSO spec and document it. Now THAT would be "educational" in the sense of EAB :)

I thought the test of the installed system was part of it, as well as meeting the FAR, though...documenting that the installation complied with certain specs, as well. Either way, it's a nit, anyway.

I think the bigger take-away is the analogy to the ADS-B equipage and installation: buy the right "parts" install them, validate their performance per the appropriate FARs, you're good to go (in an Experimental).

E.g., I fully expect that with my Dynon XPDR receiving data both from SkyView and directly from my 430W (with updated firmware which makes it compliant), and sending out appropriate ADS-B packets, that I'm done with the ADS-B out part, now and after 2020, in my RV-7A. I'd be willing to bet Mr. McClellan a steak dinner on that. :)

Meanwhile, until 2020 rolls around, I get ADS-B In traffic in addition to weather, TFRs, etc. I'm a happy flyer with the system, and I expect it to only improve.
 
No Vendor Response?

Kinda spooky that none of the industry types have commented AT ALL on Mac's blog. They are sponsors of this site and frequently introduce new products here. I would think they would be the first to jump up and protect this new piece of electricity. Isn't this their new cash cow?

....unless
 
I found this FAA publication very enlightening as in contrast to the AC it actually directly addresses experimental aircraft:

http://www.faa.gov/nextgen/ga/media/AEA-ADS-B Installation.pdf

That article Does a good job of summarizing AC 20-165A. You may be able to instal non-Certified ADSB equipment in an EAB and operate that equipment while squawking a SIL=0, but you will not be able to operat this equipment in airspace requiring ADSB out equipment after the "2020" rule takes affect, if it even happens..

Operating "certified" ADSB equipment in an EAB is where things get tricky. While it is correct to say that that the FAA does not regulate how you install equipment in experimental aircraft, they do, or will regulate how ADSB out equipment is used in "ADSB required airspace" in the future. Currently there is no guidance that I am aware of that outlines a process that would prove the installation of "certified" ADSB equipment in an EAB would meet the system integrity level required of AC 20-165A. Keep in mind the system integrity level includes testing to ensure antennas are located so they provide 100% signal coverage during all phases of flight to ensure there is no loss of position reporting, position "ghosting" etc. this is why the FAA is requiring an STC for installation on certified aircraft. Once the first article STC has been accomplished and proven that the system installation and system performance integrity is acceptable, then if follow on STC installations are performed correctly as per the STC documentation you will be assured that the installation wil meet the SIL performance requirements.
Having read all of the current FAA guidance I don't see how you could be legally operating "certified" ADSB equipment in an EAB while squawking anything other than SIL=0 since the installation is not FAA approved or accepted for use in the NAS.
FYI Advisory Circulars are never "mandatory" nor are they "regulation" they are a FAA documents that provides guidance for complying with FAA regulations, same applies to FAA Orders and FAA Policy Letters.
 
No Transponder below 18,000 ft ?????

Mac states "The fact is that by far most of the country's airspace is wide open below 18,000 Feet, and you don't even need a transponder to fly through it"

Thank's for the education Mac! All this time I thought it was Mode C above 10,000 MSL.

Roger Bloomfield
 
Thank You Mike

Thank you Mike...
You may be able to instal non-Certified ADSB equipment in an EAB and operate that equipment while squawking a SIL=0, but you will not be able to operat this equipment in airspace requiring ADSB out equipment after the "2020" rule takes affect, if it even happens..

That said, why are manufacturers trying to sell us equipment that they apparently know will NOT be legal unless regulation changes are made prior to 2020? More than one avionics manufacturer, retailer, installer is pitching "satisfies the mandate" when apparently it does not. Irresponsible? And not a single manufacturer is willing to participate in this conversation. Of course they still can...
 
What manufacturer has stated that their equipment which does not meet the TSO requirements for ADS-B out will satisfy the 2020 mandate?

Using the logic being presented here, us EAB guys better not ever turn on our transponders.....or use a TSO'd navigator to shoot a real approach.
 
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What manufacturer has stated that their equipment which does not meet the TSO requirements for ADS-B out will satisfy the 2020 mandate?

Using the logic being presented here, us EAB guys better not ever turn on our transponders.....

From Dynon's page ref their transponder:

SkyView SV-XPNDR-261 and SV-XPNDR-262 Mode-S Transponders:

Integrated: Made for the SkyView System with control and annunciation appearing on the SkyView Display. The transponder module can be mounted anywhere in the airplane that is convenient.

Traffic: Features TIS Traffic (USA).

ADS-B Out via 1090 ES: Meets USA and Europe ADS-B Out Mandates. Note, full FAA "2020 mandate" ADS-B Out compliance requires a TSO'd WAAS be connected.
Additional U.S. ADS-B OUT Compliance Information: The FAA ADS-B "final rule" only allows the higher power Class 1 transponder to be used as an ADS-B Out transmit device for ADS-B Out mandate compliance on or after 2020. Therefore, for U.S. customers, we recommend only the Class 1 SV-XPNDR-261.

There is currently a discussion on the Dynon forum - including Dynon input. I'll be sitting back watching it all - who knows what happens in the next 5 years.
 
Sorry but you did not answer my question by referencing Dynon's page. Dynon's page looks accurate to me.
 
From Dynon's page ref their transponder:

SkyView SV-XPNDR-261 and SV-XPNDR-262 Mode-S Transponders:

Integrated: Made for the SkyView System with control and annunciation appearing on the SkyView Display. The transponder module can be mounted anywhere in the airplane that is convenient.

Traffic: Features TIS Traffic (USA).

ADS-B Out via 1090 ES: Meets USA and Europe ADS-B Out Mandates. Note, full FAA "2020 mandate" ADS-B Out compliance requires a TSO'd WAAS be connected.
Additional U.S. ADS-B OUT Compliance Information: The FAA ADS-B "final rule" only allows the higher power Class 1 transponder to be used as an ADS-B Out transmit device for ADS-B Out mandate compliance on or after 2020. Therefore, for U.S. customers, we recommend only the Class 1 SV-XPNDR-261.

There is currently a discussion on the Dynon forum - including Dynon input. I'll be sitting back watching it all - who knows what happens in the next 5 years.


Perhaps you should have read their documentation a little further:

Compliance ETSO 2C112b Class 1 Level 2els, ETSO C166a Class B0,
TSO C112c Class 1 Level 2els, TSO C166b Class B1S

http://www.dynonavionics.com/docs/SkyView_XPNDR-26X.html

The statement on compliance is in the installation documentation, as well.

That same poster on the Dynon forum who keeps insisting on "antenna to antenna" validation or certification was wrong before, and he's wrong now.
 
Sorry but you did not answer my question by referencing Dynon's page. Dynon's page looks accurate to me.

Yeah, didn't read your post closely enough - thought you were only asking which manufacturer is stating their equip meets the mandate.
 
In regards to the general anti-ADS-B attitude of some people and organizations, reprints of articles from the '70s with the words Transponder, Mode C or TCA removed and replaced with ADS-B could match what we have recently read.

At the moment it seems to be (to me) much ado about nothing.

Costs will come down. Transponders used to be pricey. Now they come in a box of crackerjacks.
 
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Yeah, didn't read your post closely enough - thought you were only asking which manufacturer is stating their equip meets the mandate.

And which part of this do you assert they do not meet?

§91.225 Automatic Dependent Surveillance-Broadcast (ADS-B) Out equipment and use.
(a) After January 1, 2020, and unless otherwise authorized by ATC, no person may operate an aircraft in Class A airspace unless the aircraft has equipment installed that—
(1) Meets the requirements in TSO-C166b, Extended Squitter Automatic Dependent Surveillance-Broadcast (ADS-B) and Traffic Information Service-Broadcast (TIS-B) Equipment Operating on the Radio Frequency of 1090 Megahertz (MHz); and
(2) Meets the requirements of §91.227.
(b) After January 1, 2020, and unless otherwise authorized by ATC, no person may operate an aircraft below 18,000 feet MSL and in airspace described in paragraph (d) of this section unless the aircraft has equipment installed that—
(1) Meets the requirements in—
(i) TSO-C166b; or
(ii) TSO-C154c, Universal Access Transceiver (UAT) Automatic Dependent Surveillance-Broadcast (ADS-B) Equipment Operating on the Frequency of 978 MHz;
(2) Meets the requirements of §91.227.​
 
Perhaps you should have read their documentation a little further:



http://www.dynonavionics.com/docs/SkyView_XPNDR-26X.html

The statement on compliance is in the installation documentation, as well.

That same poster on the Dynon forum who keeps insisting on "antenna to antenna" validation or certification was wrong before, and he's wrong now.

I'm a Dynon fan, I merely misread Brantel's post. Not trying to get anyone's panties in a wad - saying who is right, or wrong.
 
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