ADSB visibility with non certified GPS

On Thursday, September 21, 2017 at 6:34:01 PM UTC-4, wrote:
Clarification...

Trig TN72 with Trig TT22 WILL be seen as having a non-zero quality indicator. (good)

Trig TN72 with Brand X Mode S/ADSB out, almost certainly has a zero quality indicator (not good).



On Thursday, September 21, 2017 at 4:34:34 PM UTC-5, WaltWX wrote:
You make a very good observation...

So, what's the point of using a TABS TN72 with a Trig system if no one can see it?

Daryl... do you have any insights on this?

This has been discussed here many times over. The GPS source alone is not approved. It is the combination of the GPS and the mode S transponder that is approved. Please read up on the FAA website first about approved combinations, then search through this forum for additional information.

What hasn't been discussed is how often non-approved ADSB out sources are actually being ignored.

On Thursday, September 21, 2017 at 6:20:54 PM UTC-7, wrote:
What hasn't been discussed is how often non-approved ADSB out sources are actually being ignored.

Ah I think we've been over what matters here many times, but it is a mess.

100% of certified ADS-B in systems will ignore the ADS-B data from 100% of ADS-B Out systems that use a COTS/non-complaint GPS source 100% of the time..

So airliners, fast jets, regional jets, etc. which if they have ADS-B In at all will be a certified In system, definitely won't see some scabby ADS-B Out install using a COTS GPS source. Since many of those aircraft today have TCAS II they will be see the transponder via TCAS and be able to issue TCAS TA and RA fro that target. However the gap in the middle is with many high-end GA aircraft that have certified ADS-B In but no TCAS, they won't see a crappy COTS driven ADS-B Out. But at the low-end GA market non-certified portable ADS-B In systems will see those COTS powered targets. That is kinda brain dead but it's how it is and easy to work around.. don't use a COTS GPS source....

With the relatively low price of theTN72, if owners want to equip an experimental glider with ADS-B Out there is no excuse anymore for using a COTS GPS source. I really don't want to get into how many GA aircraft might or might not be affected, just do it properly and install a TN72 or TN70 system. COTS GPS is just the wrong thing.

Darryl,

Thanks for the reply. Very helpful.

Gary

Jumping into the middle of this - what's the real reason to ignore an
ADS-B Out aircraft simply because the GPS source is "crappy"?Â* So what
if the position is off by 100 feet or so?Â* My PowerFLARM routinely
reports targets at 200 feet or more altitude difference, e.g., I may get
a report of a target 100 feet high and spot him a hundred feet or so
lower than I am.

It just seems ridiculous to ignore another aircraft which might be on a
collision course simply because his altitude or position may be reported
as a couple of hundred feet different from where he is. That's what
looking outside is for.Â* Following the same logic, of what use is a
non-TSO compliant GPS in an experimental aircraft if it will be ignored
by other aircraft?

Inquiring minds and all...Â* BTW, I plan on installing a TN70 to mate
with my TT22 in my certificated glider.

On 9/21/2017 7:41 PM, Darryl Ramm wrote:
On Thursday, September 21, 2017 at 6:20:54 PM UTC-7, wrote:
What hasn't been discussed is how often non-approved ADSB out sources are actually being ignored.
Ah I think we've been over what matters here many times, but it is a mess.

100% of certified ADS-B in systems will ignore the ADS-B data from 100% of ADS-B Out systems that use a COTS/non-complaint GPS source 100% of the time.

So airliners, fast jets, regional jets, etc. which if they have ADS-B In at all will be a certified In system, definitely won't see some scabby ADS-B Out install using a COTS GPS source. Since many of those aircraft today have TCAS II they will be see the transponder via TCAS and be able to issue TCAS TA and RA fro that target. However the gap in the middle is with many high-end GA aircraft that have certified ADS-B In but no TCAS, they won't see a crappy COTS driven ADS-B Out. But at the low-end GA market non-certified portable ADS-B In systems will see those COTS powered targets. That is kinda brain dead but it's how it is and easy to work around.. don't use a COTS GPS source....

With the relatively low price of theTN72, if owners want to equip an experimental glider with ADS-B Out there is no excuse anymore for using a COTS GPS source. I really don't want to get into how many GA aircraft might or might not be affected, just do it properly and install a TN72 or TN70 system. COTS GPS is just the wrong thing.


--
Dan, 5J

Looking into the TN70 a question comes to mind:Â* Can the GPS output be
split and used to feed the ClearNav, PowerFLARM, Dynon D10a, and
ClearNav Vario?Â* It seems such a shame to have FIVE GPS antennae on one
glider...Â* What about using one of those power splitters I've seen here
on RAS?

On 9/22/2017 10:06 AM, Dan Marotta wrote:
Jumping into the middle of this - what's the real reason to ignore an
ADS-B Out aircraft simply because the GPS source is "crappy"?Â* So what
if the position is off by 100 feet or so?Â* My PowerFLARM routinely
reports targets at 200 feet or more altitude difference, e.g., I may
get a report of a target 100 feet high and spot him a hundred feet or
so lower than I am.

It just seems ridiculous to ignore another aircraft which might be on
a collision course simply because his altitude or position may be
reported as a couple of hundred feet different from where he is.
That's what looking outside is for.Â* Following the same logic, of what
use is a non-TSO compliant GPS in an experimental aircraft if it will
be ignored by other aircraft?

Inquiring minds and all...Â* BTW, I plan on installing a TN70 to mate
with my TT22 in my certificated glider.

On 9/21/2017 7:41 PM, Darryl Ramm wrote:
On Thursday, September 21, 2017 at 6:20:54 PM UTC-7,
wrote:
What hasn't been discussed is how often non-approved ADSB out
sources are actually being ignored.
Ah I think we've been over what matters here many times, but it is a
mess.

100% of certified ADS-B in systems will ignore the ADS-B data from
100% of ADS-B Out systems that use a COTS/non-complaint GPS source
100% of the time.

So airliners, fast jets, regional jets, etc. which if they have ADS-B
In at all will be a certified In system, definitely won't see some
scabby ADS-B Out install using a COTS GPS source. Since many of those
aircraft today have TCAS II they will be see the transponder via TCAS
and be able to issue TCAS TA and RA fro that target. However the gap
in the middle is with many high-end GA aircraft that have certified
ADS-B In but no TCAS, they won't see a crappy COTS driven ADS-B Out.
But at the low-end GA market non-certified portable ADS-B In systems
will see those COTS powered targets. That is kinda brain dead but
it's how it is and easy to work around.. don't use a COTS GPS source....

With the relatively low price of theTN72, if owners want to equip an
experimental glider with ADS-B OutÂ* there is no excuse anymore for
using a COTS GPS source. I really don't want to get into how many GA
aircraft might or might not be affected, just do it properly and
install a TN72 or TN70 system. COTS GPS is just the wrong thing.



--
Dan, 5J

Dan

The reason to ignore ADS-B traffic data from non-conforming aircraft is because thats what the standards say to do. I think this comes in via TSO-C195 and the RTCA standards it incorproates but I'm not going to spend time chasing this down now.

And if you are an RTCA committee member focused on airlines and government regulators and and avionics manufactures... and care about critical IFR spacing, ground surface spacing, etc. and know that COTS GPS errors can be way more than a few hundred feet at times... then surely you would argue that is reasonable. And from their view surely nobody is going to want to fly around transmitting ADS-B Out using a crappy COTS GPS that don't have trusted reliability ( e.g. like RAIM).

The eventual come back on this was.... the development of TSO-C199/TABS which is a middle ground that leverages COTS type technology internally. Unfortunately the FAA never closed the loop to allow TSO-C199 GPS sources for ADS-B Out in certified gliders.

I also don't want to think lots of aircraft could have random COTS GOPS connected to an ADS-B Out and be flying around close to dense traffic areas. It's all frustrating as well since all this is inherently insecure, with no encryption or authentication and bad actors could already do a lot of harm injecting fake traffic into the ADS-B system. This non-compliant ADS-B traffic display hurdle does nothing to stop that. Why the designers of ADS-B did not implement authentication, encryption and some form of useful security is beyond me. Oh well we need to keep the NAS primary radar systems around anyhow.... for when all this goes tits up.

It might be time to get used to what the airlines and high-end users want. With FAA privatization there may be much more of that....


On Friday, September 22, 2017 at 9:07:06 AM UTC-7, Dan Marotta wrote:
Jumping into the middle of this - what's the real reason to ignore an
ADS-B Out aircraft simply because the GPS source is "crappy"?Â* So what
if the position is off by 100 feet or so?Â* My PowerFLARM routinely
reports targets at 200 feet or more altitude difference, e.g., I may get
a report of a target 100 feet high and spot him a hundred feet or so
lower than I am.

It just seems ridiculous to ignore another aircraft which might be on a
collision course simply because his altitude or position may be reported
as a couple of hundred feet different from where he is. That's what
looking outside is for.Â* Following the same logic, of what use is a
non-TSO compliant GPS in an experimental aircraft if it will be ignored
by other aircraft?

Inquiring minds and all...Â* BTW, I plan on installing a TN70 to mate
with my TT22 in my certificated glider.

On 9/21/2017 7:41 PM, Darryl Ramm wrote:
On Thursday, September 21, 2017 at 6:20:54 PM UTC-7, wrote:
What hasn't been discussed is how often non-approved ADSB out sources are actually being ignored.
Ah I think we've been over what matters here many times, but it is a mess.

100% of certified ADS-B in systems will ignore the ADS-B data from 100% of ADS-B Out systems that use a COTS/non-complaint GPS source 100% of the time.

So airliners, fast jets, regional jets, etc. which if they have ADS-B In at all will be a certified In system, definitely won't see some scabby ADS-B Out install using a COTS GPS source. Since many of those aircraft today have TCAS II they will be see the transponder via TCAS and be able to issue TCAS TA and RA fro that target. However the gap in the middle is with many high-end GA aircraft that have certified ADS-B In but no TCAS, they won't see a crappy COTS driven ADS-B Out. But at the low-end GA market non-certified portable ADS-B In systems will see those COTS powered targets. That is kinda brain dead but it's how it is and easy to work around.. don't use a COTS GPS source....

With the relatively low price of theTN72, if owners want to equip an experimental glider with ADS-B Out there is no excuse anymore for using a COTS GPS source. I really don't want to get into how many GA aircraft might or might not be affected, just do it properly and install a TN72 or TN70 system. COTS GPS is just the wrong thing.


--
Dan, 5J

On Thursday, September 21, 2017 at 4:23:14 PM UTC-7, Andrzej Kobus wrote:
On Thursday, September 21, 2017 at 6:34:01 PM UTC-4, wrote:
Clarification...

Trig TN72 with Trig TT22 WILL be seen as having a non-zero quality indicator. (good)

Trig TN72 with Brand X Mode S/ADSB out, almost certainly has a zero quality indicator (not good).



On Thursday, September 21, 2017 at 4:34:34 PM UTC-5, WaltWX wrote:
You make a very good observation...

So, what's the point of using a TABS TN72 with a Trig system if no one can see it?

Daryl... do you have any insights on this?


Yes discussed many times over. But aw heck lets go over that and some other stuff again. Well because this stuff is better than dietary fiber...

This has been discussed here many times over. The GPS source alone is not approved. It is the combination of the GPS and the mode S transponder that is approved. Please read up on the FAA website first about approved combinations, then search through this forum for additional information.

Well the GPS sources are approved in they may meet say meet TSO-C145 or TSO-C199 or "meets requirements of TSO-C145", or maybe meet none of those of a COTS GPS etc. and that stuff is important to understand.

Trig is correct in what they say. Certified ADS-B In receivers and the ADS-B ground infrastructure will ignore all ADS-B out systems using COTS GPS. Airliners, fast jets, etc. not receiving any of that crap. (that does not stop TCAS seeing the aircraft via transponder interrogation).

The Trig TT22 with 1090ES Out driven by a TN72 GPS source, all properly installed, will be seen by all aircraft with 1090ES In, both portable and certified/fixed install systems. It will also be seen by all aircraft with UAT In if within ADS-R service coverage. However you can only install a TN72 in an experimental aircraft. Certified aircraft, including gliders, requires you use a TN70 as all ADS-B Out installs in certified aircraft must meet 2020 compliance requirements (which effectively require an actual TSO'ed TSO-C145 GPS source in a certified aircraft, including glider).

An ADS-B Out 2020 complaint install (which sticking with Trig, requires a TN70 not a TN72 GPS source) will be seen by all aircraft. Wether that is with a TSO-C145 GPS source (for certified aircraft), or a "meets performance requirements of a TSO-C145 source (an option for experimental aircraft).... as long as they are all properly installed of course. trig foes not have a lower cost "non-TSO but meets performance requirements of TSO-C145 GPS source".

In an experimental aircraft not intended to fly where the 2020 carriage mandate applies (pop quiz: where do gliders need ADS-B out even with the carriage exemption? No it's not above 10.000') can install any GPS source as long as the ADS-B Out sets the correct quality parameters, and any old COTS GPS will require SIL=0 to be set which will guarantee that is ignored by aircraft with certified ADS-B In systems. It will still be seen by many portable ASD-B receivers, and certainly will be seen by PowerFLARM 1090ES In (assuming we are talking 1090ES Out).

The Trig TN72 is a TABS/TSO-C199 device, it is not TSO-C145, you can not install it in any certified aircraft (including gliders) and you can't use it to meet 2020 Carriage mandate requirements, but you can install it in an experimental aircraft for use outside ADS-B Out required carriage areas (including for gliders anywhere the 2020 carriage exemption lets you fly without compliant ADS-B out)...

And if your experimental glider is so equipped with a TN72 GPS source driving a Trig TT22 and it's properly installed then it *will* paint your glider on certified ADS-B In systems, both via direct 1090ES and via ADS-R for UAT In equipped aircraft. The TT22 importantly also ensures TCAS II systems can issue a RA (resolution advisory) against the glider, a pure UAT Out systems with no transponder cannot and will not cause TCAS to issue an RA. UAT Out equipped aircraft are also never visible to PowerFLARM (they can trigger PCAS if also transponder equipped), so for that reason avoid UAT Out use in gliders and towplanes.

A properly configured TT22 and TN72 GPS source will also trigger ADS-B ground services for your aircraft when in range of ADS-B ground stations (which won't help at all with PowerFLARM which can't decode any of those ground based services, to receive ADS-R, or TIS-B, or FIS-B ground services you also need a separate ADS-B In/non-PowerFLARM receiver as well as a suitable ADS-B Out system. And with reception on UAT to receive FIS-B).

---

On mixed installs with other potential ADS-B Out systems I would want to see the details of what exact ADS-B Out transponder is being used, but a TN72 in an experimental aircraft may well work with multiple different transponder options. TSO-C199 was intended to provide interoperability like that. And that will get you ground services and visibility on certified ADS-B In receivers. But be sure to ask the vendor if not Trig that they guarantee all that works... In practice the way to go today for ADS-B Out in gliders in the USA is to start with a Trig TT22 and use the TN-70 or TN72 and follow Trig's install documentation exactly.

---

Unfortunately Trig, who makes great stuff--their TT22 and associated GPS are great products, is saying some stuff that is a little sloppy again, their comment about triggering traffic services for gliders is made without the warning that a PowerFLARM can't receive those services. And they don't qualify TN72 is only for experimental gliders... I wish we had regulations that provided installs of that in certified gliders, as far as I understand we do not. I wish there were regulations (and maybe a STC) that allowed that. I'll talk to Trig and see if they can help be clearer here.

On Thursday, September 21, 2017 at 9:28:52 PM UTC-4, Darryl Ramm wrote:


Well the GPS sources are approved in they may meet say meet TSO-C145 or TSO-C199 or "meets requirements of TSO-C145", or maybe meet none of those of a COTS GPS etc. and that stuff is important to understand.

Trig is correct in what they say. Certified ADS-B In receivers and the ADS-B ground infrastructure will ignore all ADS-B out systems using COTS GPS. Airliners, fast jets, etc. not receiving any of that crap. (that does not stop TCAS seeing the aircraft via transponder interrogation).

The Trig TT22 with 1090ES Out driven by a TN72 GPS source, all properly installed, will be seen by all aircraft with 1090ES In, both portable and certified/fixed install systems. It will also be seen by all aircraft with UAT In if within ADS-R service coverage. However you can only install a TN72 in an experimental aircraft. Certified aircraft, including gliders, requires you use a TN70 as all ADS-B Out installs in certified aircraft must meet 2020 compliance requirements (which effectively require an actual TSO'ed TSO-C145 GPS source in a certified aircraft, including glider).

An ADS-B Out 2020 complaint install (which sticking with Trig, requires a TN70 not a TN72 GPS source) will be seen by all aircraft. Wether that is with a TSO-C145 GPS source (for certified aircraft), or a "meets performance requirements of a TSO-C145 source (an option for experimental aircraft)..... as long as they are all properly installed of course. trig foes not have a lower cost "non-TSO but meets performance requirements of TSO-C145 GPS source".

In an experimental aircraft not intended to fly where the 2020 carriage mandate applies (pop quiz: where do gliders need ADS-B out even with the carriage exemption? No it's not above 10.000') can install any GPS source as long as the ADS-B Out sets the correct quality parameters, and any old COTS GPS will require SIL=0 to be set which will guarantee that is ignored by aircraft with certified ADS-B In systems. It will still be seen by many portable ASD-B receivers, and certainly will be seen by PowerFLARM 1090ES In (assuming we are talking 1090ES Out).

The Trig TN72 is a TABS/TSO-C199 device, it is not TSO-C145, you can not install it in any certified aircraft (including gliders) and you can't use it to meet 2020 Carriage mandate requirements, but you can install it in an experimental aircraft for use outside ADS-B Out required carriage areas (including for gliders anywhere the 2020 carriage exemption lets you fly without compliant ADS-B out)...

And if your experimental glider is so equipped with a TN72 GPS source driving a Trig TT22 and it's properly installed then it *will* paint your glider on certified ADS-B In systems, both via direct 1090ES and via ADS-R for UAT In equipped aircraft. The TT22 importantly also ensures TCAS II systems can issue a RA (resolution advisory) against the glider, a pure UAT Out systems with no transponder cannot and will not cause TCAS to issue an RA. UAT Out equipped aircraft are also never visible to PowerFLARM (they can trigger PCAS if also transponder equipped), so for that reason avoid UAT Out use in gliders and towplanes.

A properly configured TT22 and TN72 GPS source will also trigger ADS-B ground services for your aircraft when in range of ADS-B ground stations (which won't help at all with PowerFLARM which can't decode any of those ground based services, to receive ADS-R, or TIS-B, or FIS-B ground services you also need a separate ADS-B In/non-PowerFLARM receiver as well as a suitable ADS-B Out system. And with reception on UAT to receive FIS-B).

---

On mixed installs with other potential ADS-B Out systems I would want to see the details of what exact ADS-B Out transponder is being used, but a TN72 in an experimental aircraft may well work with multiple different transponder options. TSO-C199 was intended to provide interoperability like that. And that will get you ground services and visibility on certified ADS-B In receivers. But be sure to ask the vendor if not Trig that they guarantee all that works... In practice the way to go today for ADS-B Out in gliders in the USA is to start with a Trig TT22 and use the TN-70 or TN72 and follow Trig's install documentation exactly.

---

Unfortunately Trig, who makes great stuff--their TT22 and associated GPS are great products, is saying some stuff that is a little sloppy again, their comment about triggering traffic services for gliders is made without the warning that a PowerFLARM can't receive those services. And they don't qualify TN72 is only for experimental gliders... I wish we had regulations that provided installs of that in certified gliders, as far as I understand we do not. I wish there were regulations (and maybe a STC) that allowed that. I'll talk to Trig and see if they can help be clearer here.


What changes in the above explanation if we substitute TT21 for TT22? I already have a TT21 installed in an Experimental glider.

On Friday, September 22, 2017 at 4:30:19 PM UTC-7, son_of_flubber wrote:
On Thursday, September 21, 2017 at 9:28:52 PM UTC-4, Darryl Ramm wrote:


Well the GPS sources are approved in they may meet say meet TSO-C145 or TSO-C199 or "meets requirements of TSO-C145", or maybe meet none of those of a COTS GPS etc. and that stuff is important to understand.

Trig is correct in what they say. Certified ADS-B In receivers and the ADS-B ground infrastructure will ignore all ADS-B out systems using COTS GPS. Airliners, fast jets, etc. not receiving any of that crap. (that does not stop TCAS seeing the aircraft via transponder interrogation).

The Trig TT22 with 1090ES Out driven by a TN72 GPS source, all properly installed, will be seen by all aircraft with 1090ES In, both portable and certified/fixed install systems. It will also be seen by all aircraft with UAT In if within ADS-R service coverage. However you can only install a TN72 in an experimental aircraft. Certified aircraft, including gliders, requires you use a TN70 as all ADS-B Out installs in certified aircraft must meet 2020 compliance requirements (which effectively require an actual TSO'ed TSO-C145 GPS source in a certified aircraft, including glider).

An ADS-B Out 2020 complaint install (which sticking with Trig, requires a TN70 not a TN72 GPS source) will be seen by all aircraft. Wether that is with a TSO-C145 GPS source (for certified aircraft), or a "meets performance requirements of a TSO-C145 source (an option for experimental aircraft)..... as long as they are all properly installed of course. trig foes not have a lower cost "non-TSO but meets performance requirements of TSO-C145 GPS source".

In an experimental aircraft not intended to fly where the 2020 carriage mandate applies (pop quiz: where do gliders need ADS-B out even with the carriage exemption? No it's not above 10.000') can install any GPS source as long as the ADS-B Out sets the correct quality parameters, and any old COTS GPS will require SIL=0 to be set which will guarantee that is ignored by aircraft with certified ADS-B In systems. It will still be seen by many portable ASD-B receivers, and certainly will be seen by PowerFLARM 1090ES In (assuming we are talking 1090ES Out).

The Trig TN72 is a TABS/TSO-C199 device, it is not TSO-C145, you can not install it in any certified aircraft (including gliders) and you can't use it to meet 2020 Carriage mandate requirements, but you can install it in an experimental aircraft for use outside ADS-B Out required carriage areas (including for gliders anywhere the 2020 carriage exemption lets you fly without compliant ADS-B out)...

And if your experimental glider is so equipped with a TN72 GPS source driving a Trig TT22 and it's properly installed then it *will* paint your glider on certified ADS-B In systems, both via direct 1090ES and via ADS-R for UAT In equipped aircraft. The TT22 importantly also ensures TCAS II systems can issue a RA (resolution advisory) against the glider, a pure UAT Out systems with no transponder cannot and will not cause TCAS to issue an RA.. UAT Out equipped aircraft are also never visible to PowerFLARM (they can trigger PCAS if also transponder equipped), so for that reason avoid UAT Out use in gliders and towplanes.

A properly configured TT22 and TN72 GPS source will also trigger ADS-B ground services for your aircraft when in range of ADS-B ground stations (which won't help at all with PowerFLARM which can't decode any of those ground based services, to receive ADS-R, or TIS-B, or FIS-B ground services you also need a separate ADS-B In/non-PowerFLARM receiver as well as a suitable ADS-B Out system. And with reception on UAT to receive FIS-B).

---

On mixed installs with other potential ADS-B Out systems I would want to see the details of what exact ADS-B Out transponder is being used, but a TN72 in an experimental aircraft may well work with multiple different transponder options. TSO-C199 was intended to provide interoperability like that. And that will get you ground services and visibility on certified ADS-B In receivers. But be sure to ask the vendor if not Trig that they guarantee all that works... In practice the way to go today for ADS-B Out in gliders in the USA is to start with a Trig TT22 and use the TN-70 or TN72 and follow Trig's install documentation exactly.

---

Unfortunately Trig, who makes great stuff--their TT22 and associated GPS are great products, is saying some stuff that is a little sloppy again, their comment about triggering traffic services for gliders is made without the warning that a PowerFLARM can't receive those services. And they don't qualify TN72 is only for experimental gliders... I wish we had regulations that provided installs of that in certified gliders, as far as I understand we do not. I wish there were regulations (and maybe a STC) that allowed that. I'll talk to Trig and see if they can help be clearer here.


What changes in the above explanation if we substitute TT21 for TT22? I already have a TT21 installed in an Experimental glider.

The TT-21 does not have enough output power to meet the 2020 carriage requirements, so you can't use it to do that (for those remaining areas like Class B or C airspace as mentioned above etc.).

While in an experimental glider you can connect any GPS source you want as long as the system is correctly configured to transmit the GPS parameters. But I'm not sure if the TT-21 firmware is updated to fully work with the TN-72. If it can be used and can transmit a SIL0 quality indicator then it would trigger ADS-B ground services and be seen on certified ADS-B In systems.

You need to check in with Trig support and ask them about all this. Trig are usually very responsive. Swapping out/upgerading the TT-21 to a TT-22 may end up being the best way to go.

Anybody considering installing a transponder in a glider in the USA should be looking at a Trig TT-22 not a TT-21 (and all other brands are really non-starters ). I've talked about this with most USA glider equipment dealers that they should know this, and hopefully are advising purchasers. Trig was blindsided on this, the FAA created this issue with requiring higher 1090ES Output power after the TT-21 was already shipping in the USA.

---

And to keep making sure certified glider owners feel bad, doing ADS-B out with a TT-21 in a certified glider is not ever an option as it does not meet the 2020 mandate equipment requirements, regardless of what you want to use it for it must meet those requirement in a certified aircraft.