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G3x autopilot interface

kaweeka

Well Known Member
Just want to hear from folks who have used the G3x touch with and without the GMC 305/307 interface. Is it worth the added cost? Are there any features you don't get when you just use the screen interface? From a practical standpoint with occasional IMC, is it worth it?
Dave
 
Having the dedicated interface is well worth it and I highly recommend the 307's added features over the 305.

The screen based AP interface works fine but it takes up screen space that is too valuable to give up in IMC.
 
I started out wishing I had the controller, but the more I use the screen interface the more I can get along without it. I think the new G5 will make it even less of a wish for me.

Jim
 
I'm with Brian on this one. I started out without the controller and after spending many hours in training for IFR I finally gave up and went with the 305. I wish I had the 307 but that came out later.
 
Without a doubt it is worth the cost. Go for the 307. It's my biggest regret in my panel to not have a dedicated hard interface.
 
Stand-alone LVL button for G3X touch?

I swear I read somewhere the ability to have a separate button to act like the level key (LVL) does on the GMC 307, but in the case where you only have the GDU460 and servos. I have a spare button on my stick grip I could allocate to such a purpose, but for the life of me I can't find reference to this anywhere in the install or operating manual. Was I dreaming, or does this possibility actually exist?
Cheers,
Tom.
 
Screens do fail, for hardware and or software issues. All these remote boxes are great but if the screen goes dark you could find yourself in pickle. The easy answer of course is a back up screen. That comes with the extra cost, weight and complexity, and maybe the same computer glitch takes it as well.
A solution is to keep a dedicated autopilot interface, one panel mounted com and at least an ident button if you have a remote transponder.
Idiot lights for oil pressure and a low voltage light will let you get home if your screen fails in VFR conditions.
I have had old school gyros fail in previous aircraft and my main ?new? screen fail three times in the rocket in the last 9 years of new tech.
Plan around the what if.....
 
+1 for 305-307.

We like having the controller as it makes things go so much better to set up before take-off and in flight. As the soft wear has been updated the 305 does as good as the 307 now with the Alt. inputs being set by the basil knob on the GDU. If you were just going out for a half hour and hand flying it is not needed at all, but who does not go places with an RV. I find anytime I am going more than 50 mile to a spot or another airport it is so easy to punch up the F.D. set the flight plan, roll down the runway, brake ground and punch-up Auto and let him take the wheel. Then I can make course and altitude corrections as I set back and watch it do it's thing. Yes, Auto and a 305 or 307 is a good friend to have with you and we would do it again. The older controller with the new soft wear is probably a good deal now to save some money on your build.
Hope this helps. R.E.A. III # 80888
 
Level Mode

In response to Tom's comment, you can wire a discrete input to the GEA 24 and configure it for a level mode input.

I do not have GMC 305 or 307 in my G3x touch panel. I do not find myself wishing for one while flying. I have about 150 hrs on this configuration with quite a bit of IFR and cross countries. That being said I can definitely appreciate the benefits of the GMC. There really isn't room in my panel for one which is what drove my decision. I do have a second display which acts as a back controller.

To answer an above question, all functions of the GMC 305 including level mode show up on the pop up AFCS window, but it does require two touch screen button presses versus one key press.

In summary, If you have the room and funds, you would never regret putting in a GMC. The 307 is the best GMC for G3X. If you for some reason you can't put one in (cost or fit), you can absolutely operate the airplane effectively without one.
 
Excellent. Thanks Levi. I have subsequently found reference to it in the G3X installation manual. There's not a lot, but Page 34-163 in the descrete input configuration section outlines what is necessary:

•AFCS Level - Used in conjunction with the autopilot to activate LVL mode. This input should be connected to a momentary pushbutton.

I found myself flying solo the other day when I received a text message about the weather up ahead. It would have been very nice to just be able to say "hey buddy, can you just fly it for a sec" with just the press of the button so I could reply to the text.
To the other fellas, as much as I'd love another piece of fruit in my aeroplane, I've got to work out how to wire it all together, so I didn't want to over complicate things. My bank account has also been squealing like a stuck pig lately, which doesn't help the situation. That said, in addition to one GDU460 and GTN625 I also have a backup G5 and Aera 660 with their own internal batteries, so many times more redundancy than any certified aircraft I have flow. The redundancy for the autopilot is my left arm. Beyond that, I will have to rely on the training I have received from the Black Knight:
https://www.youtube.com/watch?v=Sl4zXroojwM
Tom.
 
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Around 3y of flying with single GDU 460 and a 305 here.
In my experience, IFR- particularly the approach phase, using the screen is pretty much a no go if you only have one GDU.
Also the added redundancy of having an autopilot if the GDU goes dark is important.
I?ve had mine go dark once, thankfully VMC.
All depends on your mission. VFR can live without. IFR I wouldn?t.
 
Richard are you using the display full screen or split? I always fly split screen with the ElFIS on the left and map or approach plate on the right. I do not have the 305 so I have to tap the AP control on the top of the EFIS to bring up the autopilot window on the right side. I fly IFR with this configuration and I don't find myself wishing for more. The EFIS is always up on the left half and the plate or map is only covered up with the AP control screen for a moment, then put away.

I thought I was going to want the AP control head but the only thing I wish I could do is install a discrete button to activate the right side control screen and then put it away again with the same button.

I think if I had gotten used to the control head I probably would think I couldn't live without it.

Jim
 
Hi Jim.
Yes this is pretty much how I am set up as well.
For me the issue is more one of unwanted PFD changes in the approach phase.

In my view having any PDF configuration changes while flying an approach in IMC is not risk free.
My approach checklist bans all touching of the screen past the IAF.

Also, It?s pretty easy to have more than one go at something on the touch screen if it?s bumpy. The touch screen requires 3 discrete touches to achieve the same as one touch on the GMC.

I agree you?d be pleasantly surprised at how easy a GMC would make your life :)
 
I just upgraded from non touch dual screen to single touch large screen. No GMC room on my panel so I go without. I've been playing with it IFR, coupled and have no complaints. It can't definitely be left out and considering how huge the GMC is (really Garmin?) I suspect some will leave it out. I am content without it.
 
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