ADS-B out with a non TSO'd 1201 GPS sensor?

[[email protected]]

How does a FAA radar confirm if a non TSO'd GPS is connected to a mode S, ADS-B out transponder?

Wonder if we'll soon see a transponder, ELT,or perhaps PowerFLARM offer an option to include a TSO'd 1201 WAAS/GPS sensor board?

OK, so the transponder costs $2,300 and a TSO'd 1201 WAAS/GPS sensor adds another $3,000>$7,000. That warm and fuzzy feeling rushes over me knowing the FAA is looking out for the aviation hobbyist.

Lets count...ELT, PowerFLARM, CNV, CN MFD, Butterfly vario, PNA, SPOT, cellphone...8 GPS devices. The FAA must be looking for an ice cube because any or all above could probably have saved the Titanic from that iceberg.

Remember...whoever dies with the most computers and GPS devices wins.

[T[_2_]]

On Nov 12, 9:41*am, wrote:
> How does a FAA radar confirm if a non TSO'd GPS is connected to a mode S, ADS-B out transponder?
>
> Wonder if we'll soon see a transponder, ELT,or perhaps PowerFLARM offer an option to include a TSO'd 1201 WAAS/GPS sensor board?
>
> OK, so the transponder costs $2,300 and a TSO'd 1201 WAAS/GPS sensor adds another $3,000>$7,000. That warm and fuzzy feeling rushes over me knowing the FAA is looking out for the aviation hobbyist.
>
> Lets count...ELT, PowerFLARM, CNV, CN MFD, Butterfly vario, PNA, SPOT, cellphone...8 GPS devices. The FAA must be looking for an ice cube because any or all above could probably have saved the Titanic from that iceberg.
>
> Remember...whoever dies with the most computers and GPS devices wins.

I've been told that the ADS-B out data includes GPS quality/
reliability information that comes from the WAAS receiver. Basically a
"trust me" code. Hopefully the cost of WAAS GPS recievers will come
down in costs as we approach 2020.

[Andy[_1_]]

On Nov 12, 7:18*pm, T > wrote:
> I've been told that the ADS-B out data includes GPS quality/
> reliability information that comes from the WAAS receiver. Basically a
> "trust me" code. Hopefully the cost of WAAS GPS recievers will come
> down in costs as we approach 2020.

The Trig transponders have provision for setting the GPS data
integrity level in the configuration menus. If I had one I'd connect
any available GPS and set the integrity to LOW. I'm not asserting
that is either approved or legal.

From the installation manual:

"GPS System Integrity Level
An important metric for ADS-B ground system behaviour is the SIL or
System Integrity Level. It is intended to reflect the probability that
the GPS position source is providing erroneous information. A detailed
analysis of the contribution to system integrity is outside the scope
of this manual, and the installer may need to carry out a system
safety analysis to determine the best value to set. However, a
reasonable guideline might be:
Equipment
Transmitted Integrity Level
VFR only GPS or uncertified installation
Low
GPS installation certified for en-route and terminal IFR navigation
Medium
GPS installation certified with augmentation, such as WAAS or LAAS
High"

Andy

[Darryl Ramm]

On Tuesday, November 13, 2012 3:22:40 PM UTC-8, Andy wrote:
> On Nov 12, 7:18*pm, T > wrote:
>
> > I've been told that the ADS-B out data includes GPS quality/
>
> > reliability information that comes from the WAAS receiver. Basically a
>
> > "trust me" code. Hopefully the cost of WAAS GPS recievers will come
>
> > down in costs as we approach 2020.
>
>
>
> The Trig transponders have provision for setting the GPS data
>
> integrity level in the configuration menus. If I had one I'd connect
>
> any available GPS and set the integrity to LOW. I'm not asserting
>
> that is either approved or legal.
>
>
>
> From the installation manual:
>
>
>
> "GPS System Integrity Level
>
> An important metric for ADS-B ground system behaviour is the SIL or
>
> System Integrity Level. It is intended to reflect the probability that
>
> the GPS position source is providing erroneous information. A detailed
>
> analysis of the contribution to system integrity is outside the scope
>
> of this manual, and the installer may need to carry out a system
>
> safety analysis to determine the best value to set. However, a
>
> reasonable guideline might be:
>
> Equipment
>
> Transmitted Integrity Level
>
> VFR only GPS or uncertified installation
>
> Low
>
> GPS installation certified for en-route and terminal IFR navigation
>
> Medium
>
> GPS installation certified with augmentation, such as WAAS or LAAS
>
> High"
>
>
>
> Andy

It sounds like you are talking about an older DO260a (the RTCA spec that defines 1090ES data-out) version of a Trig transponder or at least the documentation that came with one. If you are playing with ADS-B data-out with a Trig transponder, even if you are using a non-compliant NMEA GPS source, you probalby want to get the current DO260b firmware and setup instructions from the factory (no longer included in the manual).

DO260b significantly changes some of the over the air transmission of SIL, NIC, NACp, and NACv data that describes the GPS systems specs and performance and how that data is provided.

Its unclear how the FAA ADS-B infrastructure will deal with DO260a transmitters in future, I've heard some opinion they will just be ignored past a certain date.


Darryl

[Darryl Ramm]

On Tuesday, November 13, 2012 3:22:40 PM UTC-8, Andy wrote:
> On Nov 12, 7:18*pm, T > wrote:
>
> > I've been told that the ADS-B out data includes GPS quality/
>
> > reliability information that comes from the WAAS receiver. Basically a
>
> > "trust me" code. Hopefully the cost of WAAS GPS recievers will come
>
> > down in costs as we approach 2020.
>
>
>
> The Trig transponders have provision for setting the GPS data
>
> integrity level in the configuration menus. If I had one I'd connect
>
> any available GPS and set the integrity to LOW. I'm not asserting
>
> that is either approved or legal.

Ah but please don't do that in a certified glider, if discovered I would not be surprised if the FAA made an example of any pilot, owner or A&P involved. This is all too high a visibility within the FAA to expect them to ignore transgressors.

Certified aircraft currently require an STC or which there are very few at the moment (but the few that exist are often AML (Approved Model List) STCs so apply to several aircraft makes/models at a time), but there are no STCs for gliders and nobody working on one AFAIK. Eventually the FAA is expected to remove the STC requirement... but still to require a currently expensive TSO'ed IFR/WAAS GPS.

As a part of the current STC requirement the FAA has made it clear that FSDOs are forbidden from issuing any field/337 approvals for any ADS-B data-out installs. Any A&P tryign to pull a "minor repair" or "lets not sign the logbook at all" stunt on an ADS-B data-out install is taking a bad risk.

Darryl

[Andy[_1_]]

On Nov 13, 7:54*pm, Darryl Ramm > wrote:
> It sounds like you are talking about an older DO260a (the RTCA spec that defines 1090ES data-out) version of a Trig transponder or at least the documentation that came with one. If you are playing with ADS-B data-out with a Trig transponder, even if you are using a non-compliant NMEA GPS source, you probalby want to get the current DO260b firmware and setup instructions from the factory (no longer included in the manual).
>

Although I downloaded the installation manual, rather than using a
version I had on file, it seems I still used an out of date version.

The current version, which is available at
http://www.trig-avionics.com/library/TT2x-00560-00-AK.pdf, does not
include the previously quoted text.

Thanks for the correction.


Andy

[[email protected]]

On Wednesday, November 14, 2012 10:56:40 AM UTC-6, Andy wrote:
> On Nov 13, 7:54*pm, Darryl Ramm > wrote:
>
> > It sounds like you are talking about an older DO260a (the RTCA spec that defines 1090ES data-out) version of a Trig transponder or at least the documentation that came with one. If you are playing with ADS-B data-out with a Trig transponder, even if you are using a non-compliant NMEA GPS source, you probalby want to get the current DO260b firmware and setup instructions from the factory (no longer included in the manual).
>
> >
>
>
>
> Although I downloaded the installation manual, rather than using a
>
> version I had on file, it seems I still used an out of date version.
>
>
>
> The current version, which is available at
>
> http://www.trig-avionics.com/library/TT2x-00560-00-AK.pdf, does not
>
> include the previously quoted text.
>
>
>
> Thanks for the correction.
>
>
>
>
>
> Andy

HI - (This is Tim Taylor form Freeflight Systems - we make the 1201 WAAS)
First - on the checks - the FAA looks at the message you are sending which includes both position and also integrity info. Part of the integrity info is calculated real time by the GPS and part of it is fixed based on the certification level of the equipment. The real time data includes integrity of position (horizontal and vertical) and velocity (horizontal and vertical). If any of these fall below the ADS-B rule standards for any extended period, the ADS-B ground system (the SBS) flags you as "invalid" and does not pass your info on to ATC. The data does go to the airworthiness guys at the FAA and they care about installs that are transmitting but not valid. The second thing they do is check your reported position against other data they have (radar for example) and then they compare what you are saying against what they observe. If that comes out wrong you get to hear from them pretty quick. Depending on where you are, you might also see an F-16 drop by for a look.

Bottom line - if you put this stuff on your airplane you need to meet the rules - otherwise you are at best carrying weight you don't need and at worst inviting MIB to say hi.

That said, I still would want it on any airplane I was in - when it is done right you are putting some real protection around your own ship - and ATC has eyes on you - with their computer automation ready to flag any potential conflicts.

You might also want to look art 978 (UAT) ADS-B - small and light. If you are not required to have a transponder, this is a good alternative (and if you already have on it is not affected) We do significantly reduce the price of the 1201 if it is bundled with an ADS-B radio so the price is not crazy

Sorry for the long answer

[Darryl Ramm]

On Wednesday, November 14, 2012 3:52:44 PM UTC-8, wrote:

> You might also want to look art 978 (UAT) ADS-B - small and light. If you are not required to have a transponder, this is a good alternative (and if you already have on it is not affected) We do significantly reduce the price of the 1201 if it is bundled with an ADS-B radio so the price is not crazy

Actually UAT data-out in gliders is an _awful_ alternative.

Tim, you might want to do a bit of studying up on the sailplane/glider market.

Gliders in the USA already widely utilize PowerFLARM collision avoidance technology, the PowerFLARM (as used int the USA) includes a 1090ES receiver.

Even if a glider owner/pilot did not have a PowerFLARM they ought to be considerate to and aware that many other gliders they are likely to fly with will be equipped with these boxes with 1090ES data-in and to some extent those gliders will overtime likely equip with 1090ES data-out.

Gliders fly in many broad geographic locations and at times at low altitudes/close ground/mountain ridge etc. proximity where there is unlikely to be good ADS-R coverage so advocating UAT data-out for gliders may lead to lots of inter-operation issues, confusion, and is really not helpful.

And you may also not be aware of glider-community saftey programs run in some area where there are concerns about glider traffic near high density airline and fast jet traffic. There are quire a few glides int these areas that have already installed Mode C or Mode S transponders--critical for any compatibility with TCAS. The current transponder favored by glider pilots in the USA seems to be the Trig TT21/TT22. These are interesting as well to some purchasers as they provide a path to 1090ES data-out.

UAT data-in or data-out is effectively a dead duck in the USA glider market..

Darryl

[Mike Schumann[_2_]]

On Wednesday, November 14, 2012 6:52:44 PM UTC-5, wrote:
> On Wednesday, November 14, 2012 10:56:40 AM UTC-6, Andy wrote:
>
> > On Nov 13, 7:54*pm, Darryl Ramm > wrote:
>
> >
>
> > > It sounds like you are talking about an older DO260a (the RTCA spec that defines 1090ES data-out) version of a Trig transponder or at least the documentation that came with one. If you are playing with ADS-B data-out with a Trig transponder, even if you are using a non-compliant NMEA GPS source, you probalby want to get the current DO260b firmware and setup instructions from the factory (no longer included in the manual).
>
> >
>
> > >
>
> >
>
> >
>
> >
>
> > Although I downloaded the installation manual, rather than using a
>
> >
>
> > version I had on file, it seems I still used an out of date version.
>
> >
>
> >
>
> >
>
> > The current version, which is available at
>
> >
>
> > http://www.trig-avionics.com/library/TT2x-00560-00-AK.pdf, does not
>
> >
>
> > include the previously quoted text.
>
> >
>
> >
>
> >
>
> > Thanks for the correction.
>
> >
>
> >
>
> >
>
> >
>
> >
>
> > Andy
>
>
>
> HI - (This is Tim Taylor form Freeflight Systems - we make the 1201 WAAS)
>
> First - on the checks - the FAA looks at the message you are sending which includes both position and also integrity info. Part of the integrity info is calculated real time by the GPS and part of it is fixed based on the certification level of the equipment. The real time data includes integrity of position (horizontal and vertical) and velocity (horizontal and vertical). If any of these fall below the ADS-B rule standards for any extended period, the ADS-B ground system (the SBS) flags you as "invalid" and does not pass your info on to ATC. The data does go to the airworthiness guys at the FAA and they care about installs that are transmitting but not valid. The second thing they do is check your reported position against other data they have (radar for example) and then they compare what you are saying against what they observe. If that comes out wrong you get to hear from them pretty quick. Depending on where you are, you might also see an F-16 drop by for a look.
>
>
>
> Bottom line - if you put this stuff on your airplane you need to meet the rules - otherwise you are at best carrying weight you don't need and at worst inviting MIB to say hi.
>
>
>
> That said, I still would want it on any airplane I was in - when it is done right you are putting some real protection around your own ship - and ATC has eyes on you - with their computer automation ready to flag any potential conflicts.
>
>
>
> You might also want to look art 978 (UAT) ADS-B - small and light. If you are not required to have a transponder, this is a good alternative (and if you already have on it is not affected) We do significantly reduce the price of the 1201 if it is bundled with an ADS-B radio so the price is not crazy
>
>
>
> Sorry for the long answer

So what is the price???

[[email protected]]

One of the approved units is the FreeFlight Systems 1201. It is posted here for less than $3000.00. However, it is only sold "installed" so additional expense.

http://sarasotaavionics.com/avionics/1201

Probably should run everything - -(what it's connected to, intended use,and installer)- - by your FAA FSDO before spending any $$$$.$$. Go back up and read Darrly Ramm's Nov.13 post which says "FAA has made it clear that FSDOs are forbidden from issuing any field/337 approvals for any ADS-B data-out installs".

Beats me.

[Darryl Ramm]

On Sunday, November 18, 2012 9:17:29 AM UTC-8, wrote:
> One of the approved units is the FreeFlight Systems 1201. It is posted here for less than $3000.00. However, it is only sold "installed" so additional expense.
>
>
>
> http://sarasotaavionics.com/avionics/1201
>
>
>
> Probably should run everything - -(what it's connected to, intended use,and installer)- - by your FAA FSDO before spending any $$$$.$$. Go back up and read Darrly Ramm's Nov.13 post which says "FAA has made it clear that FSDOs are forbidden from issuing any field/337 approvals for any ADS-B data-out installs".
>
>
>
> Beats me.

OK this is actually more complex than I tried to put it earlier and things just changed recently and deserves a longer more careful reply. This is all pretty boring, remember the important technology related collision avoidance things today are really installing a PowerFLARM and/or a transponder. We are just starting to see the availability of suitable ADS-B data-out and GPS devices. There is no rush...

I had mentioned the need for a STC for an ADS-B data-out install since that has and effectively still currently controls what is installable. The prohibition on the use of field approvals/337 for ADS-B data-out installs was issued by a FAA Memorandum on August 30 2010 (http://www.aea.net/governmentaffairs/pdf/ADS-B%20memo%20102010.pdf)

Very recently this has been superseded by another Memorandum on November 5, 2012
(http://download.aopa.org/aircraft/121105faa-ads-b.pdf)

This is paired with FAA Advisory Circular AC 20-165A that provides guidance for the installation and approval of ADS-B data-out installs. See http://www.faa.gov/documentLibrary/media/Advisory_Circular/AC%2020-165A.pdf

This new memorandum _does_ opens up field approval/337 based installs in some situations, but only when:

- The ADS-B data-out and GPS devices are TSO approved
- Where equivalent/similar installations that have previously been approved via STC (e.g. consisting of the same GPS, ADS-B data-out system and wiring etc.).
- Manufacturer installation instructions are followed etc.
- Relevant parts of AC 20-165 are followed.

If somebody really wants to do an install in a certified glider, I would suggest not starting an inquiry about that with a FSDO, I would start with manufacturer or third party STC owners, understand as much as you can from them, see if any existing STCs apply or gives field approval coverage under the current memo, and then take this to the FSDO. If there are no existing STC of the same equipment then the FSDO cannot help you at all with a field approval (with a certified aircraft).

Trig, or actually their partner Pereguine, (http://www.peregrine.aero) has an STC approval for the TT31 transponder with a FreeFlight 1201 WAAS/GPS See http://www.trig-avionics.com/press120404.html The STC is SR00744DE for a Mooney M20C (the AML lists only the M20C)

AFAIK this STC concerns only the Trig TT-31 transponder and so is not a basis under the FAA November 5, 2012 memo for a field approval/337 installation in a certified glider. I am not sure where things are with the TT22, I'll try to check. But once there is a STC that covers that and if anybody us willing to buy an expensive TSO'ed GPS they could try for a field approval install in a certified glider.

FreeFlight Systems also has a STC for their RANGR UAT data-out with the 1201 GPS/WAAS and that will lead to installs under the new field approval/337 process. But again that is a UAT device and because its UAT has lots of compatibility concerns for gliders with PowerFLARMs 1090ES data-in.

ADS-B data-out in non-certified gliders clearly does not work via STCs or field approval/337 there my assumption is as much as possible its good to you follow the applicable parts in CFR 14 91.227 and AC 20-165A as well as the manufactures instructions. There is still the intent of setting SIL=0 to flag the GPS source is not approved (the FAA specifically calls that out in AC 20-165), but here is a lot more to think about.

And there are so many different rules, buzzwords and specs etc. that fly around with ADS-B that I thought I'd just try to just list the main ones here and say what they are

The relevant ADS-B data-out FARs are

CFR 14 91.225. -- the basic requirements for carriage of ADS-B data-out by 2020 (gliders are exempt).
CFR 14 91.227 -- technical requirements that ADS-B data-out equipped aircraft must meet.

Especially read CFR 14 91.227 and AC 20-165A together.

The main TSO and their corresponding RTCA specs you are likely to see are -

TSO-C154c RTCA/DO-282B - UAT data-out (note the RTCA 'B' rev required for FAA ADS-B compliance)
TSO-C166b RTCA/DO-260B - 1090ES data-out (note the RTCA 'B' rev required for FAA ADS-B compliance)

TSO-C195a RTCA/DO-317A - ADS-B data-in (really affects IFR class traffic displays, not relevant to gliders)

TSO-C145a RTCA/DO-229C - GPS/WAAS required for "compliant" ADS-B data-out. e.g. a FreeFlight 1201
TSO-C146a RTCA/DO-229C - GPS/WAAS systems in integrated navigation products (e.g. Garmin glass panels, these can drive ADS-B data-out just like C145a systems can).

TSO-C112c RTCA/DO-181D - Mode S transponder, all practical 1090ES data-out devices will meet this spec.

---

As I think I mentioned before, Trig TT21/22 transponders were previously DO-260A complaint and in the recent firmware version 2.1 (or higher) have been updated to DO-260B compliance and Trig has been granted the corresponding TSO-C166b approval for these transponders. Older Trig transponders can be upgraded to DO-260B compliance by returning to Southeast Aerospace (SEA) for a free firmware update, you just pay shipping. Contact Laurie Burgess at SEA ) to arrange an RMA. I don't believe the is any reason to do this update unless you want to do ADS-B data-out.

Hope some of that helps.


Darryl

[John Carlyle]

Darryl,

Thanks for taking the time and trouble to write your last post - I found it extremely informative!

Out of curiosity I did a Google search for "DO-260A versus DO-260B" to see what was changed. I found something ( http://adsb.tc.faa.gov/WG3_Meetings/Meeting24/1090-WP24-07R2-Proposed_Change_3_Candidates_1-09-09.doc ), but it was way to technical for me.

Is there anything in this DO-260A to B change that we glider pilots should understand, or is it mostly "inside baseball" stuff that's important (as you said) only if you implement ADS-B?

-John

On Monday, November 19, 2012 3:42:29 AM UTC-5, Darryl Ramm wrote:
> As I think I mentioned before, Trig TT21/22 transponders were previously DO-260A complaint and in the recent firmware version 2.1 (or higher) have been updated to DO-260B compliance and Trig has been granted the corresponding TSO-C166b approval for these transponders. Older Trig transponders can be upgraded to DO-260B compliance by returning to Southeast Aerospace (SEA) for a free firmware update, you just pay shipping. Contact Laurie Burgess at SEA ) to arrange an RMA. I don't believe the is any reason to do this update unless you want to do ADS-B data-out.

[Darryl Ramm]

On Monday, November 19, 2012 10:05:31 AM UTC-8, John Carlyle wrote:
> Darryl,
>
>
>
> Thanks for taking the time and trouble to write your last post - I found it extremely informative!
>
>
>
> Out of curiosity I did a Google search for "DO-260A versus DO-260B" to see what was changed. I found something ( http://adsb.tc.faa.gov/WG3_Meetings/Meeting24/1090-WP24-07R2-Proposed_Change_3_Candidates_1-09-09.doc ), but it was way to technical for me.
>
>
>
> Is there anything in this DO-260A to B change that we glider pilots should understand, or is it mostly "inside baseball" stuff that's important (as you said) only if you implement ADS-B?
>
>
>
> -John

John

There are important changes. But the high order message is DO-260B is the 1090ES spec required by the FAA and its likely at some time that DO-260A transmitters just won't receive the full suite of ground services (ATC, TIS-B, ADS-R) and certainly won't meet FAA 2020 carriage mandate (that gliders are exempt from anyhow).

DO-260B technically is important for the USA rollout of ADS-B. For example it changed the interpretation of capability class bits, that tell the ground infrastructure if your aircraft has 1090ES data-in and/or UAT data-in capabilities and that is used by the ground infrastructure to work out what ADS-R and TIS-B data to broadcast for to your aircraft. There were also changes in the GPS sensor quality data parameters transmitted (the SIL, NIC, NACp and NACv parameters).

There are better docs discussing changes than the one you found, here is one example..,

http://www.bangkok.icao.int/cns/meeting.do?method=download&year_id=15&meeting_id=121&doc_id=2159

Regards


Darryl

[John Carlyle]

Darryl,

Many thanks for your easy to understand version of DO-260B. I get it...

I had seen the link you provided, but it wouldn't open. I persevered once I understood it was important, and was finally successful. You're right, it was a much better document - and almost understandable! <grin>

Best regards,
John

On Monday, November 19, 2012 3:34:10 PM UTC-5, Darryl Ramm wrote:
> John
>
> There are important changes. But the high order message is DO-260B is the 1090ES spec required by the FAA and its likely at some time that DO-260A transmitters just won't receive the full suite of ground services (ATC, TIS-B, ADS-R) and certainly won't meet FAA 2020 carriage mandate (that gliders are exempt from anyhow).
>
> DO-260B technically is important for the USA rollout of ADS-B. For example it changed the interpretation of capability class bits, that tell the ground infrastructure if your aircraft has 1090ES data-in and/or UAT data-in capabilities and that is used by the ground infrastructure to work out what ADS-R and TIS-B data to broadcast for to your aircraft. There were also changes in the GPS sensor quality data parameters transmitted (the SIL, NIC, NACp and NACv parameters).
>
> There are better docs discussing changes than the one you found, here is one example..,
>
> http://www.bangkok.icao.int/cns/meeting.do?method=download&year_id=15&meeting_id=121&doc_id=2159
>
> Regards
>
> Darryl