"...Four GPS units Bob?..."
The GA35 is for the GTN650
The GA57X is for the GDL51R XM/GPS
The GA26C's are for the GDUs. These will go on the glare shield.
I will have to ask Stein about the GA26C for the G5...
Thanks guys. Four GPS units Bob? Aside from the 35 which goes up top, where did you locate the others? I was thinking I would put one on the undersurface of the overhead console. Glare shield for other two?
I have a GA 35 for my GTN and then the GA 56 for the G5. The G3X will get GPS signal from either the GTN via GAD 29 or G5 via CAN bus, so you do not need a separate antenna just for that.
Three, four or five GPS antennas? Really?
I am not an expert on Garmin glass, but for IFR I get by just fine with one SkyView GPS antenna and one GTN-650 GPS antenna. On the RV-10 both were mounted on the glare shield. Considering the temperamental aspects of the GTN-650 I now recommend mounting that GPS antenna on the cabin top. On the RV-8A and RV-8 the SkyView is on the glare shield and the GTN-650 is on the top of the fuselage just behind the passenger?s head.
The rest of the antennas are basic:
- Transponder
- ADS-B
- Two comm
- One wingtip VOR/LOC/GS
On the RV-10 I did add a piece of wire strung out under the engine (inside the cowl) for the audio panel Marker Beacon antenna. It works just fine as it has gone off flying at altitude over major airports. Other than that it has never been used an any real or practice approach. I recommend not having a Marker Beacon receiver.
Carl
The only IFR part of a GARMIN panel is either a GNS or GTN navigator -- so one antenna there. The other GPS antennas are VFR -- one for each screen as each screen has it's own built-in VFR GPS. So really there's no difference than what you have with your system.
So a dual Garmin G3X install needs a GPS antenna for each display? I would not have guessed.
Each SkyView display uses the same GPS antenna via serial ports. The functioning of one display does not affect the other in this aspect.
Carl
No -- only one GPS antenna is required just like with the Dynon. The display with the antenna will share its GPS data with multiple screens. But as each screen has its own integrated GPS most of us add the extra antenna(s) simply to add system redundancy in case of a screen failure.
For a system that is as well integrated as Garmin I'm surprised that each unit would require it's own antenna and not simply get the data from the other units on the bus.
At least one of the G3X screens needs it's own antenna, for dual screens I use one for each.
No, they work just fine with input from either external source and sharing that data, using the GTN. And having the G5 with it's own valid antenna, it can share GPS data with the G3X, much like a GPS 20 will as well. And since the OP stated they have a GTN, no additional antenna is required for the G3X. Lastly, they do have internal GPS as well, but it is not shared.
If you want your G3X to have it's own antenna, you can do that, but they don't need it. I can attest to this in practice. What's more, the GDU's will only use one GPS signal source at a time, so if you have the GTN configured to provide that signal as an external source, then the internal source (which includes attaching a GA 56 directly to the GDU) won't even be used, except as a backup you could select if the GTN failed. But, you have the G5, right? It can provide that GPS signal as well when configured with it's own antenna.
I see a GA56 for the G5 and a GA 35 for the GTN and that's redundancy and all you really need for GPS related antennas.
Maybe the G3Xpert will jump in here, the below is from their manual which I tend to believe:
7 GDU 45X (DISPLAY UNIT) INSTALLATION
NOTE
"GPS data is used for ADAHRS sensor drift correction, so at least one source of GPS data is required. This requirement can be met by installing a GPS 20A, or by connecting a GPS antenna to at least one GDU GPS receiver. In a system with multiple GDU displays, additional GPS antennas may be connected to the other displays for redundancy, if desired."
"...Four GPS units Bob?..."
The GA35 is for the GTN650
The GA57X is for the GDL51R XM/GPS
The GA26C's are for the GDUs. These will go on the glare shield.
I will have to ask Stein about the GA26C for the G5...
Hello Randy,Building an IFR machine and am planning dual G3X, G5, and GTN750. Aside from the WAAS antenna which I believe is the GA35, what other GPS antennae would be recommended?
Walt, the GDU's only use the the individually attached GPS antenna for ADAHRS data while using navigation data from an external source, such as a GTN. But this data is also being provided on CAN bus from the G5, so the additional antenna connected to the GDU is simply more redundancy. I'm not saying don't do it - for that matter you can attach an antenna to both PFD, MFD and even a third GDU, if desired - I'm simply saying it's not needed and the OP's question is "What antennas do I need?"
I have done this setup and it works well.
Hello Randy,
As explained in the G3X installation manual, at least one of the GDU 4XX displays must have an antenna connected unless you have a GPS 20A, but even in that case, we still recommend an antenna on the PFD display for backup to the GPS 20A.
I like to tell customers that the most important GPS in the aircraft is not the GTN, but rather the high performance WAAS GPS receiver built into each GDU 4XX display because it provides GPS acceleration data used by the GSU 25 ADAHRS to correct for small drifting errors in the solid state attitude sensors.
The GSU 25 ADAHRS can use air data and magnetometer data to correct for sensor drift in the absence of GPS data, but the highest level of performance and accuracy is only obtained when GPS data is available and used for aiding.
The GPS data from the GTN and G5 can be used as backup navigation data for the GDU displays, but it cannot currently be used to aid the GSU 25 ADAHRS.
Thanks,
Steve
Thanks for jumping in here Steve!
Ron, perhaps the above will change your mind? Steve is the brains behind the G3X and I take his word as gospel. I guess we could argue the semantics of "required" vs "recommended" but when the manufacturer "recommends" something they generally have a good reason for it.
Ron, The only reason I continue this silly "debate" is I think it's important that folks follow the manufacturers recommendations to achieve the level of performance designed into the system, and I wish you would stop saying that it ok to not install the recommended GPS antennas/sources because it works for you.
I think you are just reading into Steve's comments what you want to hear.
Watch my lips: It's not about redundancy.
Please read Steve's comment below again:
"I like to tell customers that the most important GPS in the aircraft is not the GTN, but rather the high performance WAAS GPS receiver built into each GDU 4XX display because it provides GPS acceleration data used by the GSU 25 ADAHRS to correct for small drifting errors in the solid state attitude sensors.
The GSU 25 ADAHRS can use air data and magnetometer data to correct for sensor drift in the absence of GPS data, but the highest level of performance and accuracy is only obtained when GPS data is available and used for aiding."
Steve has already included the GPS sources that will support the GSU25 ADAHRS aiding so no need to repeat that info again.
We recommend you install a GPS for antenna for......the G5 (e.g. GA 26C or GA 56).....
As explained in the G3X installation manual, at least one of the GDU 4XX displays must have an antenna connected unless you have a GPS 20A, but even in that case, we still recommend an antenna on the PFD display for backup to the GPS 20A........
Note also that the G5 backup instrument can use either its internal GPS receiver or the MapMX data it is receiving directly from the GTN for attitude sensor aiding, but in some kind of aircraft power emergency, where you might be left with only the G5 operating on its internal backup battery, you will be glad that you connected an antenna to the G5. Like the GSU 25, the G5 can use alternate sources of aiding, but GPS aiding provides the highest accuracy.....
Thanks,
Steve
Hello Mark,Steve,
You mentioned the the GPS 20A as playing an important part in redundancy. Will the WAAS antenna that?s part of the GDL-82 play the same redundancy roll when being installed along with a stand-alone G-5/660 combo?
Hello Mark,
The GDL 82 has a very nice WAAS GPS receiver with the same specs as the GPS 20A, but it doesn't share any GPS data with your G5/Aera 660 system (or any system for that matter).
Thanks,
Steve
Hello Mark,Thanks for the reply Steve. Is there anything that you would recommend (antenna wise) to boost the robustness/reliability/redundancy of a stand alone G-5/660 setup?
Thanks again.
Hello Randy,
We recommend you install a GPS for antenna for the GDU 4XX PFD (e.g. GA 26C or GA 56), the G5 (e.g. GA 26C or GA 56), and the GTN 750 (e.g. GA 35/36).
As explained in the G3X installation manual, at least one of the GDU 4XX displays must have an antenna connected unless you have a GPS 20A, but even in that case, we still recommend an antenna on the PFD display for backup to the GPS 20A.
I like to tell customers that the most important GPS in the aircraft is not the GTN, but rather the high performance WAAS GPS receiver built into each GDU 4XX display because it provides GPS acceleration data used by the GSU 25 ADAHRS to correct for small drifting errors in the solid state attitude sensors.
The GSU 25 ADAHRS can use air data and magnetometer data to correct for sensor drift in the absence of GPS data, but the highest level of performance and accuracy is only obtained when GPS data is available and used for aiding.
The GPS data from the GTN and G5 can be used as backup navigation data for the GDU displays, but it cannot currently be used to aid the GSU 25 ADAHRS.
Interestingly, there are 2 additional sources of GPS data (besides the GDU and GPS 20A) which provide data that can be used to aid the GSU 25, and that is a GTX 345 w/GPS and a GNX 375. Just like when using a GPS 20A, we still recommend that at least the PFD have its own antenna.
Note also that the G5 backup instrument can use either its internal GPS receiver or the MapMX data it is receiving directly from the GTN for attitude sensor aiding, but in some kind of aircraft power emergency, where you might be left with only the G5 operating on its internal backup battery, you will be glad that you connected an antenna to the G5. Like the GSU 25, the G5 can use alternate sources of aiding, but GPS aiding provides the highest accuracy.
Let us know if you have additional questions.
Thanks,
Steve
Hello Randy,
We recommend you install a GPS for antenna for the GDU 4XX PFD (e.g. GA 26C or GA 56), the G5 (e.g. GA 26C or GA 56), and the GTN 750 (e.g. GA 35/36).
As explained in the G3X installation manual, at least one of the GDU 4XX displays must have an antenna connected unless you have a GPS 20A, but even in that case, we still recommend an antenna on the PFD display for backup to the GPS 20A.
I like to tell customers that the most important GPS in the aircraft is not the GTN, but rather the high performance WAAS GPS receiver built into each GDU 4XX display because it provides GPS acceleration data used by the GSU 25 ADAHRS to correct for small drifting errors in the solid state attitude sensors.
The GSU 25 ADAHRS can use air data and magnetometer data to correct for sensor drift in the absence of GPS data, but the highest level of performance and accuracy is only obtained when GPS data is available and used for aiding.
The GPS data from the GTN and G5 can be used as backup navigation data for the GDU displays, but it cannot currently be used to aid the GSU 25 ADAHRS.
Interestingly, there are 2 additional sources of GPS data (besides the GDU and GPS 20A) which provide data that can be used to aid the GSU 25, and that is a GTX 345 w/GPS and a GNX 375. Just like when using a GPS 20A, we still recommend that at least the PFD have its own antenna.
Note also that the G5 backup instrument can use either its internal GPS receiver or the MapMX data it is receiving directly from the GTN for attitude sensor aiding, but in some kind of aircraft power emergency, where you might be left with only the G5 operating on its internal backup battery, you will be glad that you connected an antenna to the G5. Like the GSU 25, the G5 can use alternate sources of aiding, but GPS aiding provides the highest accuracy.
Let us know if you have additional questions.
Thanks,
Steve