GFC 500 first impressions

flyingcheesehead

Touchdown! Greaser!
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iMooniac
So I didn't get another upgrade... Not yet. But, a friend of mine just put a GFC500, a second G5, and a JPI 730 into his already-nice 172, and I just got back from going flying with him to check it out. My experience is mainly with the S-TEC 50 and 60-2, King KAP 140 and KFC 150 and I have a combined 1400-1500 hours behind those.

IMG_3694.jpg
(sorry for the poor picture quality, it was near sunset so lots of glare and shadows)

So, as to what's in this plane - You can see the dual G5s, JPI 730, GNS 430W, and GFC 500. It's also ADS-B equipped, with a Lynx NGT-2500 hooked to the 430W and GTX 327. I don't think anything really matters to the GFC 500 except the 430W and G5s, though.

First of all, the biggest impression I got was that we're in a different world now. The other autopilots I've used were all analog, and whatever digital gear they were coupled to was still feeding them an analog signal. With the GFC 500, the brains of the autopilot are actually in the G5, so the integration is very tight - Very much the opposite of the KAP 140 in the G1000 DA40, which I felt was exceptionally poorly integrated.

Where that shows up is that there's really no "GPSS" as such any more, at least not as a separate mode, even though GPSS is still happening. The G5 knows what the nav source on the 430W is, so if the 430's CDI is set to "GPS" and you hit the "NAV" button on the GFC500, the G5 annunciates "GPS" as the roll mode. If you hit the CDI button to change it to VLOC and there's no signal, the GFC500 will revert to "ROL" mode, again annunciated on the G5.

Like any other GPSS, this setup will nail the turns perfectly on a GPS "T" approach or really any GPS flight plan. But, I wanted to give it another challenge to see how it coped, so I set the 430W to OBS mode, dialed in a course to a nearby VOR that was 90+ degrees off our heading, then set it to HDG mode and hit NAV to arm that. Because it was going from a heading to a GPS course, I think it couldn't pre-calculate the turn the way it would on a purely GPS-based plan, and thus it didn't draw the turn on the 430W like it did with the other turns, but it did intercept the course and turned inbound toward the VOR. Because it wasn't a pre-calculated turn, it wasn't quite as smooth - It began the turn by rolling into a full standard-rate turn, then eased it out to about 10 degrees as the course wasn't coming in fast enough, and then rolled a bit more just before completing the turn.

But, that's something that none of the autopilots I've ever flown before would even be capable of, at least not without a significant overshoot of the selected course. Quite impressive. It also executed near-180 degree turns in the flight plan flawlessly.

Another thing I noticed - No more "arming" things. On my KFC 150, after preselecting an altitude, I have to hit "ARM" or it'll just blow right on past that altitude. On the GFC500, we set it for an IAS hold in the climb, and then just set the altitude bug to the desired altitude. The vertical mode annunciation on the G5 showed "IAS" in green and "ALTS" in white. 200 feet from the selected altitude, it switched to "ALTS" in green to capture, and then "ALT" to hold. No more ARM button to forget!

In both roll and pitch axes, the currently active mode is in green, and the next selected mode, if any, is in white. So, a heading to intercept an approach would show "HDG" in green and "APR" in white until intercepting, at which point "APR" would be shown in green. Very easy to read what it's doing, and the buttonology is similar to what I'm used to, yet simpler without the extra buttons.

This one was set up without the optional trim servo, and when it needed the trim changed (which only happened once) it just showed "TRIM DOWN" in yellow just below the center of the G5 AI.

We didn't play with the envelope protection or LVL mode yet, but so far I'm pretty impressed.
 
Very similar setup to what I have in my Tiger. Dual G5's, GFC500, 430W, and no automatic trim control (not an option for a Grumman). I have never flown with an auto-pilot before, so I really didn't have an expectation, other than that it would be amazing, and the setup didn't fail to deliver on that point. Auto go-around for an IFR missed approach is spot-on. It will fly pretty much whatever you want it to, assuming you've got the 430 set up correctly. I was really happy with just the dual G5's, but adding the GFC500 was the icing on the cake.
 
Very similar setup to what I have in my Tiger. Dual G5's, GFC500, 430W, and no automatic trim control (not an option for a Grumman). I have never flown with an auto-pilot before, so I really didn't have an expectation, other than that it would be amazing, and the setup didn't fail to deliver on that point. Auto go-around for an IFR missed approach is spot-on. It will fly pretty much whatever you want it to, assuming you've got the 430 set up correctly. I was really happy with just the dual G5's, but adding the GFC500 was the icing on the cake.

Ah yes, forgot that part. There's a "Go Around" button mounted just above his throttle. His is set up so that pitches up to 7 degrees nose up. I believe it also takes the GPS out of SUSP mode.
 
Sounds pretty much like my time with the GFC 700 in the G1000 equipped planes, and far cheaper than replacing my plane with one of those.
 
I would have a tough time buying the GFC500 over the Trutrak unless you are getting auto pitch trim. (We have a 182 with GFC500 and with auto pitch prim).

The auto trim seems simple enough but it does add quite a bit of parts an labor. The pitch trim switch we used as almost $300 alone. The STC replaces a pitch trim cable that hooks to the chain at the pilot's trim wheel and runs all the way under the floor and connects to s turnbuckle in the tail. Of course there is additional wiring.
 
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Yeah, but now that guy is going to sell his 172 and buy a Skywagon and do this all over again... :D (I took him for a ride in my plane last week, for all of you that aren't @flyingcheesehead )
 
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Yeah, but now that guy is going to sell his 172 and buy a Skywagon and do this all over again... :D (I took him for a ride in my plane last week, for all of you that aren't @flyingcheesehead )

Hah! I'm sure that all it'll take to get him to keep his current plane is to remind him how much time he spent stuffed into the tail, and would he like to do that again, only pointed downhill? :D
 
Hah! I'm sure that all it'll take to get him to keep his current plane is to remind him how much time he spent stuffed into the tail, and would he like to do that again, only pointed downhill? :D
He already did... in my plane :D
 
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