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GRT EchoUAT and SafeFly GPS combination

abuura

Well Known Member
I have installed the GRT EchoUAT and SafeFly GPS, the former configured by GRT to work with my 2007-vintage WS. My Public ADS-B report looks great, except for NACv (Navigation Accuracy Category for velocity), which is 100% fail. The FAA's Public ADS-B Performance Report (PAPR) User?s Guide states on page 15 that "NACv is based on design data provided by the position source manufacturer."
Question is, has anyone installed the GRT combo with a WS and experienced this problem? I am suspecting a configuration problem, since I have triple-checked the hardware connections and software settings, as set out in GRT's latest version (8) of their GPS-Safe-Fly-Install-Manual.
Any help would be appreciated.
David
 
Not one to state the obvious, (But I guess I am) have you talked to GRT tech support? They should be able to quickly identify the problem. I have the WS system and installed the Garmin GTX 335. I found them willing to assist my installation issues.
 
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I have installed the GRT EchoUAT and SafeFly GPS, the former configured by GRT to work with my 2007-vintage WS. My Public ADS-B report looks great, except for NACv (Navigation Accuracy Category for velocity), which is 100% fail. The FAA's Public ADS-B Performance Report (PAPR) User?s Guide states on page 15 that "NACv is based on design data provided by the position source manufacturer."
Question is, has anyone installed the GRT combo with a WS and experienced this problem? I am suspecting a configuration problem, since I have triple-checked the hardware connections and software settings, as set out in GRT's latest version (8) of their GPS-Safe-Fly-Install-Manual.
Any help would be appreciated.
David

The GRT manual says this:

"Sport or Horizon WS* These units are not compatible with the serial data combiner and GPS accuracy indicator functions provided by the Safe-Fly GPS, nor can these units be used to configure the Safe-Fly GPS. The Safe-Fly may be ordered pre-configured as needed at no charge, allowing it provide GPS data to your ADS-B output device. In addition, a serial output from the Safe-Fly may be configured to provide NMEA0183 GPS data to these EFIS models."

It sounds like GRT has to do some factory tweaking to the GPS unit?
 
Not one to state the obvious, (But I guess I am) have you talked to GRT tech support? They should be able to quickly identify the problem. I have the WS system and installed the Garmin GTX 335. I found them willing to assist my installation issues.

Yes, I have, and just got off the phone with Jeff. Happily, I am not the first person to encounter the NACv failure. In the first instance, uAvionics asked GRT to ascertain the user's EchoUAT Device Version, which can be found by tapping the "echo" logo at the top of the monitor page of Echo app - but that only yields a result when the app is connected to the EchoUAT. I have to wait until tomorrow to do that.
Regarding NACv, the EchoUAT is supposed to transmit that value within the data stream, but apparently is not at this time. Jeff is going to work on getting an answer from uAvionix.

In regard to this question "It sounds like GRT has to do some factory tweaking to the GPS unit?". The first time I received the Safe-Fly/Echo combo from GRT, it was not configured to work with the WS, so I sent if back. I had been pestering John for months and in his haste to satisfy my request he forgot to ask what system I have. Anyway, my Safe-Fly/Echo combo now is configured to work with the WS (and other EFISes that are not able to control the combo). As I understand it, the WS-type configuration can only be changed at GRT, since the WS is just a dumb device that can only display two things - ADS-B In data and GPS data from the Safe-Fly, which it does marvelously, I might add. What the WS cannot do it talk back to the Safe-Fly/Echo combo.

Sorry for the wordy, and perhaps overly detailed explanation, but it might be of interest to others.
 
Interesting. Please post any updates about your experiences and resolution - it will be helpful for others.
 
Good to know

This information is good to know because my brother has ordered one for his 12 and he has two GRT Sport(SX) EFIS's installed.
 
Interesting. Please post any updates about your experiences and resolution - it will be helpful for others.

Since you asked, here is an account of yesterday's flight.
- Device version. After connecting to the Echo via the app, tapped the Echo logo repeatedly, and eventually got the device version on the Monitor screen. Interestingly, the Configuration screen shows a bunch of additional information, to include three tantalizing "advanced settings" (SDA, SIL, and Transponder Threshold). The SIL showed a "1", and since the FAA's PAPR User Guide says a 2 or 3 are required to pass, I changed SIL to 3 and updated the advanced settings.
-Flight. I accomplished one flight with SIL set to 3, requested a performance report, and got a "failed to generate a result" response. I did two other flights, with SIL 2, and then SIL 1, and got the same failed result. Because the performance request does not specify a time, only a day, it's possible I got the SIL 3 failure the next two times I requested a report.
- ADS-B in. I have the SafeFly wired to serial 2 in on the WS, so that I can see ADS-B in data in addition to seeing it in Foreflight on my Iphone and Ipad. Throughout the flight, this data showed up correctly on the WS. However, on the Iphone (I didn't have the Ipad on board yesterday) the data appeared and disappeared randomly. I got an "incompatible device" message on the Foreflight Maps page once, and "ADS-B disconnect" once also - although ADS-B in data disappeared more than once.

So... I emailed all this to Jeff at GRT, and he said he would forward the info to uAvionix. The GRT SafeFly appears to be working correctly, in that the In data shows up on the WS, and the Out GPS data shown on the Echo Monitor screen is complete. The EchoUAT ADS-B Out functionality, however, does not appear to be working correctly. I hope to hear back very soon from Jeff on what might be going on there. Regarding the ADS-B In functionality, the fact that it works consistently on the hard-wired WS screen indicates it's working reliably. The fact that it is intermittent in Foreflight seems to be a Foreflight issue, not a uAvionix one. I have observed numerous "ADS-B disconnect" messages in the past when I was using my Stratux with Foreflight. See conversation at https://github.com/cyoung/stratux/issues/642 for further views on that.

As soon as I get a response from GRT I will post it. Hoping for good news...
 
The performance report shows the time (GMT) of the flight being reported, so you can tell if it was flight 1, 2, or 3.
 
The performance report shows the time (GMT) of the flight being reported, so you can tell if it was flight 1, 2, or 3.

As I wrote, the performance report REQUEST does not allow the user to specify a time, so with more than one flight in a day you cannot request a report for a specific flight. The point is if you adjust settings in an attempt to generate a report on a given day, you may not know the result.
 
I just looked at the uavionix install manual, and have a question: what transponder are you using?

I'm sure that you've triple checked your settings. The manual notes several parameters that need to be set to avoid a report failure.

About FF connectivity. You mention that you've also had trouble with Stratus connectivity in your airplane. What versions of FF and iOS are installed? Do you have the problem with both the iPad and the iPhone? What models are they? Any other WiFi devices in the plane?

I've found that sometimes having a friend go through / double check the setup procedures with you at the plane is helpful.
 
I just looked at the uavionix install manual, and have a question: what transponder are you using?

I'm sure that you've triple checked your settings. The manual notes several parameters that need to be set to avoid a report failure.

About FF connectivity. You mention that you've also had trouble with Stratus connectivity in your airplane. What versions of FF and iOS are installed? Do you have the problem with both the iPad and the iPhone? What models are they? Any other WiFi devices in the plane?

I've found that sometimes having a friend go through / double check the setup procedures with you at the plane is helpful.

Transponder: Garmin GTX330. Per uAvionix's EchoUAT installation manual "CONTROL, SQUAWK and Barometric ALTITUDE is learned wirelessly from the Legacy Transponder interrogation replies." It's only in the case of the GTX327 that a physical connection is depicted.

Settings: yes, more than triple checked. It's instructive to note that the uAvionix installation manual's appendix regarding GRT installation is for GRT units that can control the EchoUAT, which my WS is not capable of doing. GRT's manual (the latest, revision G, 8/23/17) has a section that covers installation and settings for pairing with WS. I have been over this part with Mark and Jeff several times, traced and rung every connection, reviewed every setting (to include sending screen grabs of the Echo app's screens), etc...

FF connectivity: I thought I was the only one experiencing this problem until I found the thread at https://github.com/cyoung/stratux/issues/642. I am using FF version 9.3.1, iPhone 6 Plus is running 10.3.3, iPad Pro (9.7", MLYM2LL/a) also running 10.3.3. No other wifi devices in the airplane.

EchoUAT configuration: I connected to the Echo via wifi yesterday with my computer (http://192.168.4.1) per the instructions listed at https://www.uavionix.com/support/update-echouat-software/ and http://www.uavionix.com/support/update-echouat-wi-fi-software/ and confirmed that its wifi and ads-b software versions are the latest.

Jeff is awaiting a response from uAvionix regarding their analysis of the NACv failure.

Thanks for everyone's sustained attention to this issue, and for suggested solutions.
 
Hi David,

Any updates on this story? Just curious how it all worked out. I'm about to start working on the documentation for installing the GRT SafeFly GPS and EchoUAT into the fleet of about 110 GRT-equipped Jabiru S-LSA's. It could get complicated because many of our older aircraft still have WS systems, and we've used at least 5 different models/brands of transponders... :eek:

Katie
 
Hello Katie,

We sent David's unit to uAvionics and they confirmed the NACv output error. They have since released software updates for the echoUAT to 0.3.16 and 2.4.8 which fixes the NACv output error.

We also got confirmation from uAvionics that David has flown and confirmed the NACv scaling is correct for our Safely GPS and uAvionics UAT.

As for configuration of the Safe Fly GPS, it can be changed with any current GRT EFIS (HX/HXr/SX/Mini/EX).

For those that buy the Safe Fly GPS as a stand alone, that is customers that don't have a current GRT EFIS or no GRT EFIS at all you will not be able to change the Safe Fly configuration. It will need to be factory set to the proper configuration for the connected hardware if the factory default doesn't provide the required format. We are looking into changing the default configuration that we factory set the Safe Fly GPS for the most popular use cases. If using the Safe Fly in a stand alone, let us know that and what hardware you are hooking it up to and we will factory set the configuration for you.

-Marc Robertson
Project Manager
GRT Avionics
 
As usual, GRT is both on top of the issue and communicating openly and clearly about its resolution. Just one more reason why I'm pleased with my GRT units. Now all I have to do is go fly them!
 
As usual, GRT is both on top of the issue and communicating openly and clearly about its resolution. Just one more reason why I'm pleased with my GRT units. Now all I have to do is go fly them!

I'll second that. I have had a handful of minor issues with my GRT setup and they have always been responsive and fair.

Larry
 
Safe-Fly + EchoUAT for Hx units

Hello Katie,

We sent David's unit to uAvionics and they confirmed the NACv output error. They have since released software updates for the echoUAT to 0.3.16 and 2.4.8 which fixes the NACv output error.

We also got confirmation from uAvionics that David has flown and confirmed the NACv scaling is correct for our Safely GPS and uAvionics UAT.

As for configuration of the Safe Fly GPS, it can be changed with any current GRT EFIS (HX/HXr/SX/Mini/EX).

For those that buy the Safe Fly GPS as a stand alone, that is customers that don't have a current GRT EFIS or no GRT EFIS at all you will not be able to change the Safe Fly configuration. It will need to be factory set to the proper configuration for the connected hardware if the factory default doesn't provide the required format. We are looking into changing the default configuration that we factory set the Safe Fly GPS for the most popular use cases. If using the Safe Fly in a stand alone, let us know that and what hardware you are hooking it up to and we will factory set the configuration for you.

-Marc Robertson
Project Manager
GRT Avionics

So I'm getting ready to pull the trigger on the GRT Safe-Fly system to replace the NavWorx AD600EXP unit currently in my plane. Has anyone successfully done this and gotten a 100% OK FAA performance report? Has there been any NACv failures with this setup (assuming you have the latest UAT software Ver 0.3.16 & 2.4.8)?

My installation requires that the Safe-Fly GPS to also be a secondary GPS (GPS2) as a backup to the GNS-480 Navigator for IFR operations. The manual says this can be accomplished, but has anyone else done it?

My aircraft has three Hx displays. THe NavWorx unit is currently driving all three displays. How should the the GRT Safe-Fly system be wired to get the same performance?

How dependable has the uAvionix EchoUAT been in picking up the transponder altitude & squawk codes? Have there been any FAA performance issues with this data?

Does anyone have any practical feedback for these issues?
 
So I'm getting ready to pull the trigger on the GRT Safe-Fly system to replace the NavWorx AD600EXP unit currently in my plane. Has anyone successfully done this and gotten a 100% OK FAA performance report? Has there been any NACv failures with this setup (assuming you have the latest UAT software Ver 0.3.16 & 2.4.8)?

My installation requires that the Safe-Fly GPS to also be a secondary GPS (GPS2) as a backup to the GNS-480 Navigator for IFR operations. The manual says this can be accomplished, but has anyone else done it?

My aircraft has three Hx displays. THe NavWorx unit is currently driving all three displays. How should the the GRT Safe-Fly system be wired to get the same performance?

How dependable has the uAvionix EchoUAT been in picking up the transponder altitude & squawk codes? Have there been any FAA performance issues with this data?

Does anyone have any practical feedback for these issues?

I have not done any of the above. But I am pretty sure that any HX units that are interconnected via ethernet will share traffic and weather, you only need to connect one of them to the Echo. Any HX not on the ethernet link will need its own rs232 input from the Echo.
What transponder do you have? If you have a Garmin 327 you can hard-wire it, and then have no dependence on it getting pinged, receiving the RF, etc.
 
I have not done any of the above. But I am pretty sure that any HX units that are interconnected via ethernet will share traffic and weather, you only need to connect one of them to the Echo. Any HX not on the ethernet link will need its own rs232 input from the Echo.
What transponder do you have? If you have a Garmin 327 you can hard-wire it, and then have no dependence on it getting pinged, receiving the RF, etc.

I just got off the phone with Mark Allen at GRT. He stated that he wasn't aware of the NACv failure issue with Ws units.

My aircraft has the GTX-330 transponder... Mark stated that he hasn't heard of any issues with the echoUAT getting squawk code and Alt data wirelessly from the transponder....

Relative to the Hx interconnections, his advice was to hook up the units as shown in the Rev J manual, but feed the Safe-Fly Serial out on pin 15 (blue wire) to the other EFIS serial inputs. This would give those EFIS displays the TIS-B and FIS-B data.. Only the prime display woul dbe capable of setting up parameters on the EchoUAT....
 
GRT News

"FAA Acknowledges Safe-Fly GPS
The GRT Avionics Safe-Fly GPS has been added to the available menu selections for GPS position source when requesting an FAA Public ADS-B Performance Report."
 
Echo and USB

I just finished my install of a Echo in my RV8 with a GRT Sport SX. Because of my configuration I ran out of serial ports.

Talked to Jeff at GRT and he worked with me to have the Echo input all the data thru my USB hub and the USB port in the Sport SX. I flew the airplane today and everything worked well. I requested a report and it came back with no "red" and I am in compliance. My configuration is a little different because I didn't need a WAAS position source. GNS430W, Sport SX, Echo, GTX327.
 
I just finished my install of a Echo in my RV8 with a GRT Sport SX. Because of my configuration I ran out of serial ports.

Talked to Jeff at GRT and he worked with me to have the Echo input all the data thru my USB hub and the USB port in the Sport SX. I flew the airplane today and everything worked well. I requested a report and it came back with no "red" and I am in compliance. My configuration is a little different because I didn't need a WAAS position source. GNS430W, Sport SX, Echo, GTX327.

Steve

I'm in process of an upgrade with the same GRT equipment and Garmin 327. Did you need to hardwire the UAT to your transponder, or does it it listen to the txpdr code signal?
 
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