Cessna 172 with GFC700 autopilot

TangoWhiskey

TangoWhiskey

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My FBO just received delivery of a G1000 C172 with the new integrated GFC700 autopilot and flight director. I'm trying to change my Gaston's reservation to that aircraft... I've heard good things by those that have flown the GFC700.
 
TangoWhiskey said:
My FBO just received delivery of a G1000 C172 with the new integrated GFC700 autopilot and flight director. I'm trying to change my Gaston's reservation to that aircraft... I've heard good things by those that have flown the GFC700.
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It's a sweet system. But, I'd suggest getting the training software and learning as much on the ground if you're not proficient on the G1000 suite.
 
It's terrific - is your 172 a diesel (I know they're putting the GFC700 on those)? I didn't know they'd brought the GFC700 down to the normal 172s. Definitely take the time to download the guides and buy the software. If you've never flown with a serious autopilot before be ready for some skull sweat as you learn what it does and how it works.

I can't wait to try a new Caravan this summer - The G1000 should make that more fun to fly in the weather.
 
It is really sweet. The CFI I flew with for most of my primary training sent me an e-mail earlier this week about it. He ferried a brand new 172 from ROA to HPN for a Cessna static display and was surprised to see it was equipped with the GFC700. He took a picture (attached) and said he had a lot of fun using it.

I don't think it gets any easier than this if you're fully trained and qualified.
 

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KennyFlys said:
It's a sweet system. But, I'd suggest getting the training software and learning as much on the ground if you're not proficient on the G1000 suite.
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I'm very proficient on the G1000, have Max's book, the most recent Garmin Training Software (G1000 Trainer), the PDFs... just need to read up (refresh) on how the GFC700 works versus the KAP140. Integrated has to be better. Definitely need to practice it under the hood before using in IMC.

Will be nice to set the altimeter in TWO places, not THREE... :)
 
Major potential differences:
Fright Director for hand flying
Airways in flight plans (if you've not seen this before)
WAAS gives you vertical guidance on practically ALL RNAV approaches, and the autopilot will couple to it if you wish.
VNAV mode in descent (only in descent) can follow programmed profile, but there are rules about where you set your altitude bug that might trick you and keep it from working.
FLC (Filch) mode allows you to set a specific airspeed and will adjust pitch to maintain that speed in a climb or descent. You control rate of climb with the throttle in this case.
Still have VS and pitch hold mode.
Should have Control Wheel Steering which will remember your autopilot goals but let you hand fly for a moment, or will sync the autopilot goals to whatever attitude you set.
The GFC700 WILL fly all holds, missed approaches, etc, generally without you having to play with the sequence/suspend button - learn the logic as it's different.

Best to practice with the sim and go play in VFR. Just like when the airlines first got serious automation, there are an awful lot of new Cessna owners saying "What's it doing now?" in the cockpit.

Like XM WX, once you've tasted how much the GFC700 can reduce your workload, you'll really feel deprived flying a lesser autopilot. If it had autothrottles it would be the equivalent of the latest bizjet/airline automation.
 
The GFC700 makes the KrAP140 seem like, well, a lesser autopilot. I really liked flying with it in the new 182. I just couldn't justify the extra $100k+ to get it, given that the day I took delivery I'd be out about $70k of that in depreciation.:(

The GFC700 is one slick installation. Like flying one of the big birds!
 
i am looking at a 172S with the G1000 but want the GFC700 as well. If I bought one with a King, any idea what it would cost to retrofit?
 
Must come that way from the factory. I'm not aware of this being done. I think Cessna would be the only one that could do it, and they'd have no motive.
 
Ok. Was it 07 that the gfc700 became std? Was it an option earlier?
 
I think it was more like 2008 or later for the 172. I think it first showed up in the 182 and 206 models and the 172 was later.
 
flyersfan31 said:
The GFC700 makes the KrAP140 seem like, well, a lesser autopilot. I really liked flying with it in the new 182. I just couldn't justify the extra $100k+ to get it, given that the day I took delivery I'd be out about $70k of that in depreciation.:(

The GFC700 is one slick installation. Like flying one of the big birds!
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Concur...flown both the KAP140 and the GFC700.

The GFC is a fully-integrated piece of the G1000...the KAP140 feels more like a bolted-on solution...

Take one example: Set the altitude bug in the G1000...GFC700 uses that for your altitude target. On the KAP140, you have to go to the AP head and program your altitude separately...
 
TMetzinger said:
I think it was more like 2008 or later for the 172. I think it first showed up in the 182 and 206 models and the 172 was later.
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Correct. 2007 for the 182/206. 2008 for the 172. Some others had it starting in 2006 (Beech G36).
 
JeffDG said:
Take one example: Set the altitude bug in the G1000...GFC700 uses that for your altitude target. On the KAP140, you have to go to the AP head and program your altitude separately...
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oh no!
 
I know, just making fun. I haven't flown with any sort of advanced autopilot (well, a KAP140, once)
 
I really like the GFC700 for certain things.

If you get a crossing restriction, you can use VNAV and hit it exactly at any rate of descent you want. Also nice for non-precision approaches and visual arrivals.

FLC is great for long climbs, no need to worry about stalls or inefficiency in the climb. Set Vy and up you go. Climbing 15 thousand feet the GFC700 plus rudder trim/yaw dampener is NICE.

Set FLC on the ground. If you have a problem/emergency that requires your attention right after takeoff, hit the button. Let it fly the climb out, while you deal with whatever is going on.

General accuracy of the intercepts is awesome. No wandering, hunting, nothing. About as good as it gets.

Is it worth the money? I'll let others decide.
 
Alexb2000 said:
I really like the GFC700 for certain things.

If you get a crossing restriction, you can use VNAV and hit it exactly at any rate of descent you want. Also nice for non-precision approaches and visual arrivals.

FLC is great for long climbs, no need to worry about stalls or inefficiency in the climb. Set Vy and up you go. Climbing 15 thousand feet the GFC700 plus rudder trim/yaw dampener is NICE.

Set FLC on the ground. If you have a problem/emergency that requires your attention right after takeoff, hit the button. Let it fly the climb out, while you deal with whatever is going on.

General accuracy of the intercepts is awesome. No wandering, hunting, nothing. About as good as it gets.

Is it worth the money? I'll let others decide.
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The only thing we have found that the GFC700 doesn't do that well is flight level change (FLC) in a descent. Descending through the flight levels in FLC, the autopilot tends to porpoise a lot. I never really noticed it until another Phenom captain mentioned it to me because I prefer to climb in FLC and descend in vertical speed. It depends on your mission whether to buy a plane with the GFC700 or not but in my experience, it is a solid autopilot.
 
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I agree with Jason - FLC for descents doesn't work without autothrottles, and may not work that well WITH autothrottles.

I use FLC for climbs, and normally use VS for descents unless I'm using VNAV.
 
TMetzinger said:
I agree with Jason - FLC for descents doesn't work without autothrottles, and may not work that well WITH autothrottles.

I use FLC for climbs, and normally use VS for descents unless I'm using VNAV.
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Why the distinction, Tim? With VNAV enabled, the G1000 shows you the VS required to make the programmed VNAV profile. I use VS with VNAV... I just set the VS required manually.
 
TangoWhiskey said:
Why the distinction, Tim? With VNAV enabled, the G1000 shows you the VS required to make the programmed VNAV profile. I use VS with VNAV... I just set the VS required manually.
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In VNV I don't have to set/adjust the VS, which WILL change as winds change during the descent. In VNV mode the VS will get adjusted automagically.
 
TangoWhiskey said:
Why the distinction, Tim? With VNAV enabled, the G1000 shows you the VS required to make the programmed VNAV profile. I use VS with VNAV... I just set the VS required manually.
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If ATC gives you a descent clearance then I normally select vertical speed 1500fpm in the jet. If they give you a crossing restriction then VNAV is usually easier.
 
TMetzinger said:
In VNV I don't have to set/adjust the VS, which WILL change as winds change during the descent. In VNV mode the VS will get adjusted automagically.
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Ah, you're talking about setting VNV MODE on the GFC-700 and having it follow the VNAV profile you've programmed. I just set the VNAV Profile on the PFD/MFD and then program the GFC-700 to the desired VS using CWS, as indicated on the VNAV profile "VS Required". Yes, winds change... I do have to tweak it on the way down. :)
 
HPNPilot1200 said:
If ATC gives you a descent clearance then I normally select vertical speed 1500fpm in the jet. If they give you a crossing restriction then VNAV is usually easier.
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Agreed; but you can still use the programmed VNAV profile and fly it in VS mode on the GFC-700... just requires monitoring and occasional minor adjustments from you. It's not as automatic as using VNV mode on the GFC-700, but as you said, that mode doesn't work as smoothly during descents as a stable VS descent.
 
Obviously we have some GFC700 users here. Good deal.

I agree FLC for climbs VS for descents (except VNAV).

I don't ever just let VNAV do it's thing without looking at the profile. Maybe I want to come down at 500 FPM for turbulence, or maybe there is weather below and I want to stay high until the last possible minute, etc. I can't remember a time I haven't manually adjusted the profile to my liking, other than approaches.

I also keep the MFD up on the flight plan page because of the cancel VNAV soft key. Often center will give me a crossing restriction, I'm flying it using VNAV, switch to approach (feeling airliner accurate). They immediately say descend and maintain X. I hate that.
 
VNV is rare, I think I only use it for STARs with crossing restrictions, OR if I'm navigating to an IAF and want to be at the target altitude 3 NM early or something like that. Otherwise, when I'm given "descend and maintain", like Jason, I put in the target altitude, hit the VS button, and use CWS or the nose up/down buttons to set the VS I want, usually 400 FPM in a piston single.
 
TangoWhiskey said:
Agreed; but you can still use the programmed VNAV profile and fly it in VS mode on the GFC-700... just requires monitoring and occasional minor adjustments from you. It's not as automatic as using VNV mode on the GFC-700, but as you said, that mode doesn't work as smoothly during descents as a stable VS descent.
Click to expand...

FLC is pitchy but VNAV is usually pretty stable. On the CRJ, there is no VNAV mode so VS is your only option to follow the advisory glidepath. On the GFC700 I just couple the autopilot in VNAV mode and all is well. I can always disable it and put it in VS.
 
JeffDG said:
Concur...flown both the KAP140 and the GFC700.

The GFC is a fully-integrated piece of the G1000...the KAP140 feels more like a bolted-on solution...

Take one example: Set the altitude bug in the G1000...GFC700 uses that for your altitude target. On the KAP140, you have to go to the AP head and program your altitude separately...
Click to expand...

It's such a 1st World problem. :)
 
Another use for VNAV is when on a VFR flight to dial in pattern altitude with a 2 mile along track offset. Assuming no granite is in the way, the GFC700 will handle the decent and leave you in the perfect position for your overhead break to landing.

The GFC700 is a really nice autopilot but you need to pay attention during descents that everything is configured correctly to avoid an unpleasant automation surprise.
 
No... most of the other "goals" of an autopilot are fairly easy and you can tell what they are right from the PFD - HDG, ALT, VS, FLC, NAV...

VNV is the mode that really requires looking at the flight plan, not just the sequence of the waypoints but also any altitude constraints. It's the mode most often known to cause the "what's it doing" question - in Cessna's and Boeings. I've got a research study on the topic.
 
TMetzinger said:
No... most of the other "goals" of an autopilot are fairly easy and you can tell what they are right from the PFD - HDG, ALT, VS, FLC, NAV...

VNV is the mode that really requires looking at the flight plan, not just the sequence of the waypoints but also any altitude constraints. It's the mode most often known to cause the "what's it doing" question - in Cessna's and Boeings. I've got a research study on the topic.
Click to expand...

Ok, I understand. Monitoring and staying ahead of this new automation is a skill in and of itself IMO.
 
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