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GRT Avionics Safe-Fly 2020 ADS-B Compliant GPS Module

rv8ch

Well Known Member
Patron
Anyone see this? Details below from their website. Looks very interesting.

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http://www.grtavionics.com/safeflygps.html

? 2020 ADS-B Compliant GPS Source ? Meets or exceeds FAR 91.227, TSO-C166b, TSO-C154c
? Includes Serial Port Expander, adding 3 serial ports to any GRT EFIS
? RAIM integrity monitored position data provides integrity/accuracy alerting for all GRT EFIS
? Quick startup
? No standby power required
? Machined Aluminum case adds physical and EMI protection
? Multiple, Isolated power inputs
? Includes antenna and pre-wired cable

Available Now?$495
 
I wonder if there is any way to use it as a position source when not using a get efis.
 
I wonder if there is any way to use it as a position source when not using a get efis.

Yes. The GPS is standalone and does not require other GRT equipment to use it as a position source. The GPS has multiple serial outputs that allow it to support multiple GPS message standards out of the box.

Simply connect a wire to the serial output that corresponds to the transponder on the GPS and connect it to the transponder's serial input. The same goes for other equipment such as an ELT or EFIS.

-Marc Robertson
GRT Avionics
 
Gps position source

WHat if Navworx doesn't come through and several GPS sources are listed like TN-70 that use a Nexnav p/n 21000 could that or this GPS source be used to be make the Navworx ADS600-B 2020 compliant?

Keith Rhea
RV7 250 hours
2017 Donation
 
Yes. The GPS is standalone and does not require other GRT equipment to use it as a position source. The GPS has multiple serial outputs that allow it to support multiple GPS message standards out of the box.

Simply connect a wire to the serial output that corresponds to the transponder on the GPS and connect it to the transponder's serial input. The same goes for other equipment such as an ELT or EFIS.

-Marc Robertson
GRT Avionics

That's great news. Now you could put in a TT22 transponder and this for a compliant (experimental only) ADS-B out solution for a VFR airplane. That may be the cheapest non-NavWorx option.
 
Thank You for finding a cheaper solution to my ADS-B....
I have been searching and searching for something cheaper than the 1500 dollar unites out there. This one seems to fit the bill. I hope someone can try it out and report the results for us all. :)
 
Another Question for Marc

I have dual GRT Horizon WS setup with two 430s (non-WAAS) and a 330 (non-Es) transponder. My old VFR GRT gps died a year ago but I haven't been thinking about replacing it because of my two 430s provide all the position information I need.

Will this gps fit my old WS EFIS? Can this new GRT gps provide WAAS position information to my 330? If so it might be a reason to upgrade my 330 to extended squitter. I saw (I think) where someone said it's only approved for VFR. If that's the case then I guess I'm still out of luck!
 
With RAIM reporting, why wouldn't it be suitable for IFR?

And with all due respect to GRT for their great equipment, is there any reason to believe this GPS won't be subjected to the same scrutiny by the FAA with the same detestable outcome as Navworx? I really want one of these..

Don
 
I have dual GRT Horizon WS setup with two 430s (non-WAAS) and a 330 (non-Es) transponder. My old VFR GRT gps died a year ago but I haven't been thinking about replacing it because of my two 430s provide all the position information I need.

Will this gps fit my old WS EFIS? Can this new GRT gps provide WAAS position information to my 330? If so it might be a reason to upgrade my 330 to extended squitter. I saw (I think) where someone said it's only approved for VFR. If that's the case then I guess I'm still out of luck!

The transponder output has nothing to do with IFR legality as long as it can pass a Cert. The 430's make you IFR legal for navigation, and the grt she's makes you legal for keeping the blue side up.
 
With RAIM reporting, why wouldn't it be suitable for IFR?

And with all due respect to GRT for their great equipment, is there any reason to believe this GPS won't be subjected to the same scrutiny by the FAA with the same detestable outcome as Navworx? I really want one of these..

Don

I suppose any manufacturer's units can be scrutinized by the FAA. Hopefully GRT did all their homework, and allow inspections when requested - considering recent history. This unit is *almost* 1/3 the cost of my Garmin GPS20A when factoring in the extra cost of the GPS antenna Garmin requires.
 
The transponder output has nothing to do with IFR legality as long as it can pass a Cert. The 430's make you IFR legal for navigation, and the grt she's makes you legal for keeping the blue side up.

Jesse,
Either you missed my question or I don't understand your response. In reading the GRT product website it indicates the Fly Safe gps will feed a lot of equipment WAAS gps information. I guess my questions are: 1. will it feed compliant WAAS data to my 33O using that gps information instead of my 430 gps information? 2. If I upgrade my 330 to extended squitter will I then meet 2020 ads-b out requirements?
 
IFR GPS

With RAIM reporting, why wouldn't it be suitable for IFR?

And with all due respect to GRT for their great equipment, is there any reason to believe this GPS won't be subjected to the same scrutiny by the FAA with the same detestable outcome as Navworx? I really want one of these..

Don

Designing and manufacturing an IFR legal GPS navigator is far more involved than simply having a RAIM GPS position source. This is because the entire software package including the NAV data, waypoints, approaches, enunciator displays, nav indicator display and flagging, etc must meet and be certified to FAA requirements. I suspect that this is much too enormous of an undertaking for a small avionics manufacturer.

Skylor
RV-8
 
Trig TT31

Would this add on GPS make you compliant with the Trig TT31? I have a GRT Sport with their internal GPS now?
 
Jesse,
Either you missed my question or I don't understand your response. In reading the GRT product website it indicates the Fly Safe gps will feed a lot of equipment WAAS gps information. I guess my questions are: 1. will it feed compliant WAAS data to my 33O using that gps information instead of my 430 gps information? 2. If I upgrade my 330 to extended squitter will I then meet 2020 ads-b out requirements?

My understanding is that it will. It provides 2020-compliant position to the transponder, but this has nothing to do with IFR flight.

It should do the same with a TT31.
 
GPS not certified

The GRT Safefly info says it " Meets or exceeds FAR 91.227, TSO-C166b, TSO-C154c "; it does not say it is certified to TSO-C166b or TSO-C154c. It should be legal for experimental applications but not for certified A/C or the ADSB rebate program which requires certified TSO equipment.
 
I have dual GRT Horizon WS setup with two 430s (non-WAAS) and a 330 (non-Es) transponder. My old VFR GRT gps died a year ago but I haven't been thinking about replacing it because of my two 430s provide all the position information I need.

Will this gps fit my old WS EFIS? Can this new GRT gps provide WAAS position information to my 330? If so it might be a reason to upgrade my 330 to extended squitter. I saw (I think) where someone said it's only approved for VFR. If that's the case then I guess I'm still out of luck!

The GRT ADS-B compliant GPS will not work with a 330ES. The 330ES requires ADSB+ format which is not documented.

The GRT ADS-B GPS is not a certified WAAS GPS.

-Marc Robertson
GRT Avionics
 
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With RAIM reporting, why wouldn't it be suitable for IFR?

And with all due respect to GRT for their great equipment, is there any reason to believe this GPS won't be subjected to the same scrutiny by the FAA with the same detestable outcome as Navworx? I really want one of these..

Don

I'll reiterate that several companies are producing products that "meet the performance standard" without actual TSO's. Navworx is the only one having problems with the FAA. I believe this has more to do with their approach to dealing with the FAA than what is inside their box.

Larry
 
I'll reiterate that several companies are producing products that "meet the performance standard" without actual TSO's. Navworx is the only one having problems with the FAA. I believe this has more to do with their approach to dealing with the FAA than what is inside their box.

Larry

I sent a pleasant request to Navworx this morning asking if they were out of business, I need to move on and get ADS-B in and working.

This GPS will be a part of the system.

Sport EFIS and engine monitor in and working just fine.
 
I sent a pleasant request to Navworx this morning asking if they were out of business, I need to move on and get ADS-B in and working.

This GPS will be a part of the system.

Sport EFIS and engine monitor in and working just fine.

Over the holidays I installed a new GRT HXr and TT22 transponder. My plan was to use this new GPS receiver as my position source as soon as it was available. Last weekend I decided to purchase a 430W and will now be using it as a source instead. I did talk with GRT and it seems they are being diligent and communicating with the FAA and others to be sure their solution will be accepted.

Larry
 
I'm still lost

So - Here is what I don't get:
> The Trig TT31 manual states that the unit transmits a SIL of 3 only when used in conjunction with position sources that have been tested and certified as a "system" - specifically:

GPS Unit GPS Output Setting TT31 Input Setting
Trig TN70 n/a FreeFlight/NexNav
FreeFlight 1201 n/a FreeFlight/NexNav
Accord NexNav Mini n/a FreeFlight/NexNav
Garmin GNS4x0W ADS-B+ Garmin ADSB
Garmin GNS5x0W ADS-B+ Garmin ADSB

Anything else gets a SIL of 0. So I'm still at a loss as to how to get to a 2020 compliant system with traffic etc. Anyone any clearer than I am?

Thanks!
 
Trig needs to test their "system" with the new GRT GPS in order to be allowed to switch the SIL to 3 for that configuration.

You could ask them very nicely and maybe they'll do it!

(Doesn't Trig provide the remote controlled transponder GRT offers? If so, I would expect them to do this)
 
So - Here is what I don't get:
> The Trig TT31 manual states that the unit transmits a SIL of 3 only when used in conjunction with position sources that have been tested and certified as a "system" - specifically:

GPS Unit GPS Output Setting TT31 Input Setting
Trig TN70 n/a FreeFlight/NexNav
FreeFlight 1201 n/a FreeFlight/NexNav
Accord NexNav Mini n/a FreeFlight/NexNav
Garmin GNS4x0W ADS-B+ Garmin ADSB
Garmin GNS5x0W ADS-B+ Garmin ADSB

Anything else gets a SIL of 0. So I'm still at a loss as to how to get to a 2020 compliant system with traffic etc. Anyone any clearer than I am?

Thanks!

This is where the rules are fuzzy. For normally certified airplanes, the FAA is requiring that both transmitter and GPS carry a TSO, and further that that TSO specifies which GPS (s) can be used with a given transmitter. For EAB the GPS needs to 'meet the TSO standards' but does not actually need to be TSO approved. And the installer (you) need to certify that the GPS and transmitter work together. In reality this is not complicated. The only issue you need to be concerned with is digital format: the GPS must output data in a format the transmitter can read. As noted earlier by GRT, their $500 GPS does not output in Garmin's 'ADSB+' format, and therefore will not work with transmitters (like the 330ES) that need that format.

Question for Marc: Clearly Trig has that format. Is it that tough to reverse engineer?
 
Trig needs to test their "system" with the new GRT GPS in order to be allowed to switch the SIL to 3 for that configuration.

You could ask them very nicely and maybe they'll do it!

(Doesn't Trig provide the remote controlled transponder GRT offers? If so, I would expect them to do this)

With the Trig integrated to the GRT, the configuration details about the source reliability is set within the GRT configuration, so the trig will output a SIL =3 when configured correctly. In this case, the Trig is not determining the SIL based upon the actual source mfg, only on the settings in the GRT.

Larry
 
My best understanding is that the SIL value is a value that is transmitted by the unit and that value has been determined based on reliability tests by the MFG. For a SIL value of 3 and to be worth of transmitting that value the MFG has had to have done the testing and got the approval from the FAA for that devise to transmit that. Guessing this is part of the FAAs requirement for "meeting performance" criteria. Lower values of SIL ie 0 , 1, and 2 are values that are assigned to units having lesser accuracy, reliability and includes those which have not been demonstrated or tested by the MFG.

I think this is what the AD is all about . That is the unit must demonstrate and have valid test results on file by the MFG before the FAA will allow SIL =3 be transmitted. IF it has not been tested by the MFG and/ or he is not holding the valid test reports that confirm it meets the SIL= 3 level then it gets assigned one of the other values. This may not be the exact legal definition of the issue but about as close as I can come to understanding it.

You will find all TSOd units combinations of ADSB and position sources meet the SIL=3 . For all the others you will need to question the MFG.

To get specific traffic reports back for your N number the system is designed to report back only to those units transmitting SIL=3

The above is limited to my understanding of the issue and is not necessarily the legal definition. There , It was worth what it cost you!
 
Yeah, that was my point, or question (not sure which :).

I already own a not yet installed likely bricked Navworx EXP Unit. Now since that unit included both the In/Out Transceiver and the GPS source, then in theory Navworx (if they did the work and offered the proof to the FAA which I can't tell) could perhaps argue that they tested the "system" and it meets the performance requirements (though the FAA doesn't like their GPS apparently) likewise Dynon has stated that they are only able to offer the MFG statement for what they have tested as "a system", i.e. their ADSB + their GPS source.

So, (i) how then does the 2020/Trig "Combination" get approved for a SIL of 3. Which manufacturer Trig or GRT would have to certify to "performance standards of the system" and (ii) given the FAA position on Navworx "non-certified" GPS in their system would this combination (GRT 2020 is not a certified GPS) encounter the same FAA stance?
 
Yeah, that was my point, or question (not sure which :).

likewise Dynon has stated that they are only able to offer the MFG statement for what they have tested as "a system", i.e. their ADSB + their GPS source.

So, (i) how then does the 2020/Trig "Combination" get approved for a SIL of 3. Which manufacturer Trig or GRT would have to certify to "performance standards of the system" and (ii) given the FAA position on Navworx "non-certified" GPS in their system would this combination (GRT 2020 is not a certified GPS) encounter the same FAA stance?

Dynon wants you to buy their GPS and their transponder (which is really a Trig anyway). This whole system thing is almost, but not quite, bogus. Most of the performance requirements (SIL for example) are determined solely by the GPS, while a few (transmitter power, for example) are determined solely by the transmitter. The only real 'system' requirement is that the GPS and transmitter can communicate with each other. This is not completely trivial, as there are a bunch of different protocols out there, some of them 'secret'. But really, when you connect the GPS and transmitter together, it either works or doesn't. The system can be tested by test flying and asking the FAA for an automated report. As to who is responsible: Trig says their transponder meets specs. GRT says their GPS meets specs. And you (the owner-operator) are responsible for wiring it up and installing it.
BTW, from what I can gather, the most frequent cause of test failure is failure of the box to auto switch quickly enough from air to ground mode.
 
The only real 'system' requirement is that the GPS and transmitter can communicate with each other. This is not completely trivial, as there are a bunch of different protocols out there, some of them 'secret'. But really, when you connect the GPS and transmitter together, it either works or doesn't. The system can be tested by test flying and asking the FAA for an automated report. As to who is responsible: Trig says their transponder meets specs. GRT says their GPS meets specs. And you (the owner-operator) are responsible for wiring it up and installing it.

Bob,
One of the important factors to SDA is latency. The time from the real position of the plane to when it's transmitted. This is not something easily verified and goes way beyond a simple protocol verification. It gets even worse if your data goes through a secondary processor (like an EFIS or format converter). It's particularly hard to verify this if you have no data on the inner workings of a device (like a transmitter you don't have engineering data on).

The FAA has had multiple experiences of having two TSO'd devices, one GPS and one transmitter, that they STC'd as a pair and afterwards an incompatibility was found where the position transmission was incorrect. In the FAA's experience, the protocol parsing doesn't "either work or it doesn't." Hence the reason they expect the actual paring of equipment to be evaluated for SDA, not independently. I've seen a TSO'd GPS hooked to a TSO'd transponder send out the wrong position with my own eyes even though it worked 99% of the time just fine.

All of this is why the FAA's guidance to EAB is "The FAA expects manufacturers to perform appropriate engineering efforts to ensure the equipment complies with all requirements of Section 3 of the TSO before issuing their statement of compliance." Note that the TSO's are titled "Universal Access Transceiver (UAT) Automatic Dependent Surveillance-Broadcast (ADS-B) Equipment Operating on the Frequency of 978 MHz" and "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)." The TSO's are for systems, not for standalone GPS devices. In fact, the TSO doesn't even require a GPS as it's a performance based standard and position devices other than a GPS can be used.

Not saying this can't all be done, because it's done all the time. But there is good reason that there is an expectation that the system as a whole is verified, not just the individual components. While you may think Dynon says this because we want you to buy our devices, remember that Dynon supports and has tested 5 different GPS sources with our system, so we give our customers plenty of freedom to choose.
 
Dynon,
I apologize for seeming to pick on you. I got lazy and replied to an earlier post. My real ire is aimed at the FAA, which propagated tons of rules for the transmitters and position sources, but seemed to leave out the communications interface entirely. If they had standardize that, there shouldn't have been a need to test the whole system. Of course there are other examples. Clearly the air-ground rules were written for retractable gear aircraft; now the FAA is scrambling to figure out what to do about fixed gear airplanes. I have never seen a spec on the allowable time on the runway after touchdown before switching to ground. But the FAA is somehow testing that, and telling you if you fail.
BTW, I agree 100% - the position source data should be hard wired to the transmitter, never thru an EFIS or other box.
 
My real ire is aimed at the FAA, which propagated tons of rules for the transmitters and position sources, but seemed to leave out the communications interface entirely. If they had standardize that, there shouldn't have been a need to test the whole system.

Bit of history here: Many TSOs or FARs tell you how to do something, and don't let you innovate. Industry told the FAA they were sick of this and asked the FAA to create a FAR which is performance based, not process based. The FAA did so, and hence the ADS-B rule doesn't even require a GPS at all, just that you can prove that whatever position sensing method you use is reliable and accurate enough.

If the FAA forced manufacturers to use a specific data format, this would break the idea that it's a performance based rule. What if you use a INS that doesn't output data cleanly into the desired format? What if you're building for an airliner and want to use ARINC-429 or ARINC-664? What if it makes sense for some of the GPS processing to be done in the transmitter so you can make a cheap GPS receiver? Forcing a data format removes this ability and the FAA would need to make the format fit the highest purpose (airliners).

Maybe your ire should be with companies that accept only unpublished data formats for their ADS-B transmitters than with the FAA for not forcing everyone to use one predefined one.

Even with that, not sure the FAA would allow you to fly with an untested combo. As nice as protocols are, the real world has a way of showing you problems you never considered.

--Ian Jordan
Dynon Avionics
 
Gps position sources.

Here is what I see in the Navworx installation instructions:
4.2.1 GPS Position Source
4.2.1.1 Transceiver (P/N 200-0012, 200-0013, 200-0112 and 200-0113)
The AD600-B must be configured with a GPS position source input. The GPS position source provides geometric position information to the ADS600-B to be transmitted in the ADS-B (out) messages. The GPS position source input may be obtained externally via RS-232 or ARINC 429, or internally. If the internal GPS is selected an external GPS antenna must be connected to the ADS600-B.
The following external GPS position sources have been evaluated to show compliance with AC 20-165B:
Accord Technology LLC NexNavTM mini LRU GPS Receiver, P/N 21000
FreeFlight 1201 WAAS GPS
Garmin? GNS480TM GPS/Comm Navigator
Garmin ADS-B Out+

Wonder if "been evaluated" and been tested mean the same?

And I got a passing performance report today. Only had 0.69% error on the Flight ID. Everything else was green.

Keith Rhea
Rv7 0-320 Catto Prop, MGL IEFIS, Navworx, Sandia
2017 Dues paid.
 
Maybe your ire should be with companies that accept only unpublished data formats for their ADS-B transmitters

--Ian Jordan
Dynon Avionics

Well, truth be told, that's very high on my dislike-list but I've been chastised enough previously for saying so. -:)

For the record, I chose to go with an ADSB-out system with both parts TSO'd and also TSO'd as a system, just to avoid all this mess. (And also because, for my particular already-owned avionics, it wasn't hard or overly expensive out-of-pocket)
 
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