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GPS approach with G3X touch Only

togaflyer

Well Known Member
In order to bring up a GPS approach (situational awareness only) on the G3X Touch, what database is required in order to be able to load an approach without an external source. I have the Garmin U.S. Nav database, but it does not provide the nav data/ability to load the basic GPS approach for an airport.
 
Rich,

As long as you have a Garmin U.S. Navigation Database instead of a Garmin U.S. VFR Navigation Database, and the connected GPS IFR navigator is failed (not providing either MapMX RS-232 or A429 GPS Navigation data), you should be able to load and/or activate an instrument approach using Internal flight planning on your GDU 4XX G3X Touch Display.

Steve
 
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That sucks, as they sell you the entire nav database for the G3X touch for 149$ and then the GTN is uber $$$.
So whats the point of having a NAV database in the G3X touch?
And I just renewed.
 
That sucks, as they sell you the entire nav database for the G3X touch for 149$ and then the GTN is uber $$$.
So whats the point of having a NAV database in the G3X touch?
And I just renewed.

I wouldn’t exactly call $295 Uber $$ for the GTN nav database in the scheme of airplane units.
You would not be able to legally fly IFR from the g3x anyway.
 
Steve, yes I have the one GTN 650. The system has performed flawless. Last week I was IFR, and had to quickly divert to an airport and shoot a GPS approach. A Great Wall of red had cut me off from my destination, so while sitting for three hours at that airport waiting out weather, I thought about this same situation and some what ifs. So the GTN goes out in the thick of things so what’s my fall back. Plug in waypoints and shoot a non precision approach. I would think, in my humble opinion, it would be nice to bring up an approach on the G3X without reconfiguring everything. Since, if you don’t have an external navigator, you can bring up the approach on the G3X, then why so difficult if configured to an external source. Because someone might use it in an emergency so let’s not make it readily available. Bummer!

Also, I appreciate your insight. At least I know what my options are if the GTN does go down. ��
 
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I understand there are many complex issues when it comes to system operations. Your information is detailed and I appreciate the time and the information you provided. Being a typical greedy pilot I always want more when it comes to options. It’s just the my basic viewpoint. When it happens, I would rather have a cartridge in my magazine then in my pocket.
 
I understand there are many complex issues when it comes to system operations. Your information is detailed and I appreciate the time and the information you provided. Being a typical greedy pilot I always want more when it comes to options. It’s just the my basic viewpoint. When it happens, I would rather have a cartridge in my magazine then in my pocket.
Hi Rich,

I updated my initial post above. One of my Garmin friends reminded me that if you do indeed have a failure of the GPS navigator, you can then use Internal flight planning to load an instrument approach.

I tested this with my GNX 375 and found it to be true. Once the GNX 375 is no longer providing MapMX and ARINC 429 GPS Navigation data to the G3X Touch, the system shifts to internal flight planning, and you can then load and/or activate an instrument approach.

The Internal flight planning page looks like this (with a Select Approach button) when you press Menu after the external GPS navigator failure has occurred.

VFR Approach Select.png

You should be able to simulate this by turning off your GTN or even unplugging the GTN GPS antenna.

Sorry for the earlier confusion.

Thanks,
Steve
 
This is really interesting. Will the G3X give glideslope guidance in either LPV or LNAV+V modes while operating in this reversion mode?
 
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This is really interesting. Will the G3X give glideslope guidance in either LPV or LNAV+V modes while operating in this reversion mode?

No, just lateral guidance. You would need the IFR navigator to receive the vertical GP/GS guidance needed to descend from the FAF to the runway.

Steve
 
Ok thanks. LNAV stepdown approaches are still a great option in an emergency. This is a capability that I wasn't aware of.
 
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