What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Current GTN 625 w/10" G3X. Worthit? GTN 650/750 swap out

jliltd

Well Known Member
I would like some opinions on this. If an RV is currently flying equipped with a 10" G3X Touch with dual GTR 20 comms and a GTN 625, and I happen to have brand new GTN 650's and GTN 750's in the box at the hangar, would it be worth it to swap one out with the GTN 625 and add a rabbit ears NAV antenna? There is work required either way and the 650 wouldn't require any panel work, just wiring. During the swap one of the GTR 20's would be removed.

Aside from the fact that the 750 has a larger screen with more information displayed along with full keyboard interface, the real question I am asking is this: How important are the the terrestrial-based VOR/ILS navigation signals in your real life operations? Especially when considering a flying aircraft with an existing 625 already in place and not a in-progress project prior to equipment purchasing.

For what it's worth I live near a DOD test site and it is not uncommon to loose GPS when they are jamming its signal (many times sans NOTAM).

Jim
 
Should you lose the G3X display, you lose the ability to tune your remote radios. The GTN-650 gives you the ability to still tune one radio with knobs.
 
Do you intend to fly IFR? Can you guarantee that you won't get caught VFR on top? Is most of your flying in the flats or is there terrain where you fly most? How about obstructions? I really wouldn't want to be in the clouds, or above the clouds, navigating via GPS, with no ground based nav capability and have ALL GPS ability go away. Now you are navigating via compass/magnetometer and ded reconing with no way to determine if your wind assumptions are right. How do you get down? Remember all your backups? How many are completely dependent on GPS?

All that said, when was the last time you used VORs or ILS signals? If it has been a long time, even if you had them they probably won't be much use to you if GPS goes out and you really need the signals because you might not remember your tracking skills. I am currently doing instrument training and it was shocking how rusty my VOR skills had gotten.

To paraphrase Clint Eastwood..."are you feeling lucky?" Usually hope isn't such a good plan.
 
In my opinion, the only issue is the fact that they are jamming GPS frequently. I have a 650 just because we use my plane for training, but in real life I haven?t tuned an ILS or VOR for actual use in years, if ever. The 625 is a great unit.

If the cost was not an issue, it wouldn?t be hard to add. You just run the wires from your GTR into the COM connector and you have power, ground, an audio signal and 2 ARINC wires to convert from the 625 to 650.

Would it be worth $3-4,000, IMHO, no.
 
I would like some opinions on this. If an RV is currently flying equipped with a 10" G3X Touch with dual GTR 20 comms and a GTN 625, and I happen to have brand new GTN 650's and GTN 750's in the box at the hangar, would it be worth it to swap one out with the GTN 625 and add a rabbit ears NAV antenna? There is work required either way and the 650 wouldn't require any panel work, just wiring. During the swap one of the GTR 20's would be removed.

Aside from the fact that the 750 has a larger screen with more information displayed along with full keyboard interface, the real question I am asking is this: How important are the the terrestrial-based VOR/ILS navigation signals in your real life operations? Especially when considering a flying aircraft with an existing 625 already in place and not a in-progress project prior to equipment purchasing.

Jim

Jliltd what did you end up doing? I am about to add a GTN 625 to my dual G3X touches. I also am swapping out a GMA 350C for a GMA 245 audio panel.
For what it's worth I live near a DOD test site and it is not uncommon to loose GPS when they are jamming its signal (many times sans NOTAM).
 
I ended up not buying the RV-14 referenced in the OP equipped with the GTN 625.

Instead I later bought an RV-8 with a G3X touch w/o IFR Navigator. Just a GTR 200, GTR 20, GMA 240 and GMC 307. It does have a GPS 20A GPS 20A receiver installed as a external source.

So now I am thinking of installing a new GTN 750 I had slated for another project along with a G5 backup EFIS. I will remove the GPS 20A and GTX 23ES and GDL 39. The 750 can be the new WAAS source replacing the GPS 20A and will take out the GTR 200 in the process. I will replace the GTX 23ES with a GTX 32 and GDL 82 for UAT "out". My portable GDL 52 will replace the GDL 39 for "in" (I swap the 52 between airplanes with a base mount in each).

I current have two GSU 25's in the as-delivered system. So the G5 ADAHARS failover backup isn't as big a deal. I hadn't realized before how handy a G5 can be for a back seater when placed up high on the left or right side of the panel in a tandem seater. I did a checkout from the rear seat of another RV-8 with the G5 placed where it was easy to see. Makes it real easy for an instructor in the back seat.

Jim
 
Last edited:
Back
Top