GFC500 Update

[donkaye]

4 hours ago, ArtVandelay said:

I assume there is a secret setting or something to turn it on?


Tom

 It's been 4 months since I used it, but I think you just plug it in and it works automatically.

[kpaul]

7 hours ago, Bob - S50 said:

It's been over 4 years since I retired, but I don't remember having to turn on the yaw damper.  Either that or it was such a part of the normal flow that I didn't really have to think about it.  Never noticed any yawing in the DC9.  Worked pretty well in the 757-200 but not so much in the 757-300.  That plane was so long that the pilots could be feeling light turbulence up front and the back end would be whipping around so much that the flight attendants were experiencing moderate turbulence.  Sitting in the back and looking forward you could even see the fuselage bending and twisting.

The C-130s I flew had a yaw damper...the pilots feet. 

The PC-12 has one, it is very useful for pilots that can't figure out what to do with their feet when power changes are made.  Makes for lazy pilots, but happy folks sitting in the back.

Now the Beech 400 is a different story, that plane Dutch rolls like it is its job.  I'm not sure I would fly that one with the YD inop, even though it is not required below FL280.

For planes I've flown, the YD was generally turned on shortly after the gear and flap were raised and turned off in the before landing checklist.  

On a side note it is very difficult to taxi with the YD engaged 

[EricJ]

11 hours ago, kpaul said:

The C-130s I flew had a yaw damper...the pilots feet. 

The PC-12 has one, it is very useful for pilots that can't figure out what to do with their feet when power changes are made.  Makes for lazy pilots, but happy folks sitting in the back.

Now the Beech 400 is a different story, that plane Dutch rolls like it is its job.  I'm not sure I would fly that one with the YD inop, even though it is not required below FL280.

For planes I've flown, the YD was generally turned on shortly after the gear and flap were raised and turned off in the before landing checklist.  

On a side note it is very difficult to taxi with the YD engaged 

I used to ride frequently in corporate Embraer Legacy aircraft and wound up being racing friends with one of the pilots.   I mentioned that it was a little annoying to watch the wingtips constantly move in a slow circular motion.    He said that's known as the "Embraer Waltz".   It even had a name.       I never thought to ask whether they had a YD or not, I just got the impression that it was baked into the control system for whatever reason.

[81X]

On 11/10/2019 at 11:12 AM, bradp said:

@Bob - S50 did you do the yaw damper? @81X your J has it correct? 

I got my two final quotes that I’ve been comparing.  Both 16.5amu for three servos no yaw damper.  Both shops say it’s not needed.  I wanted to ask your advice for a med body before I commit to my feet on the pedals or on the floor.  

Yes, my K has the YD and I really like it for two main reasons- making the ride nicer in rough air and also keeping the ball centered during climbs in an airplane with no rudder trim. 

Who knows- maybe the YD will keep an airplane coordinated enough to avoid a base-final spin- purely speculating. 

[201Mooniac]

19 hours ago, donkaye said:

 It's been 4 months since I used it, but I think you just plug it in and it works automatically.

In the Device Information section of the configuration, make sure Diagnostics/Data Log is enabled

[eman1200]

Brittain accutrak all day! I’m stickin’ with it!

[donkaye]

6 hours ago, 201Mooniac said:

In the Device Information section of the configuration, make sure Diagnostics/Data Log is enabled

 

6 hours ago, 201Mooniac said:

In the Device Information section of the configuration, make sure Diagnostics/Data Log is enabled

Thanks for reminding me what I did, Adam.

[LANCECASPER]

On 11/9/2019 at 4:29 PM, donkaye said:

I hope another Bravo near me gets the GFC 500 soon.  While I love the unit, and other people say it flys an approach "on rails", mine flys it on rails alright, but the rails are attached to a shallow roller coaster.  The same thing occurs with turns greater than about 30° of heading.  The pitch trim just moves too fast resulting in some pitch oscillations.   Maybe it's my installation but all cable tensions have been checked as correct.

Some Beechcraft owners are also experiencing some of the same symptoms:

https://www.beechtalk.com/forums/viewtopic.php?f=21&t=175326

[bradp]

Decided we are going to pre-wire power lead for the YD and leave it out for now.  If I want it later on, will come back to it.  Shop says I really don’t need it and I probably agree.  However, use of a CAN bus means a pretty simple single servo upgrade / hardware interface once the brackets are in. Have never gotten a complaint about the ride from my rear seat pax siting 3 ft behind me.  Going under the knife in Feb.  

[donkaye]

4 hours ago, bradp said:

Decided we are going to pre-wire power lead for the YD and leave it out for now.  If I want it later on, will come back to it.  Shop says I really don’t need it and I probably agree.  

Go first class if money is not an issue.  Put the YD in now.  You'll be glad you did.  I really didn't think I would need it either, and maybe I don't, but when things get rough, or even the thought of it getting rough, the YD is REALLY nice to have.

[ZuluZulu]

@donkaye Just curious: How thoroughly have you explored all of the GFC-500's failure modes?  Do you know what it will do in virtually every kind of failure yet?  Would appreciate hearing any insights you've gained thus far as one of the first Mooney GFC-500 guinea pigs.  

[donkaye]

5 hours ago, ZuluZulu said:

@donkaye Just curious: How thoroughly have you explored all of the GFC-500's failure modes?  Do you know what it will do in virtually every kind of failure yet?  Would appreciate hearing any insights you've gained thus far as one of the first Mooney GFC-500 guinea pigs.  

The AFMS covers Emergency Procedures and Abnormal Procedures better than any of the Bendix/King manuals ever did.  I've attached a partial copy of the Table of Contents.  The unit also monitors itself, and with the "Smart Servos", when they disconnect, they totally disconnect unlike the old type servos.

While I'm glad I upgraded to the GFC 500, I have to say I am only about 85% satisfied with it.  While most functions like flying level work very well, one of the most important ones doesn't in my airplane.   It won't fly a stable approach, but instead mildly oscillates down either the ILS or GPS approaches with vertical guidance.  I've been hesitant to talk to Garmin about it because  they helped me so much getting it working when I first had it installed.  Most of the time it's an installation issue, and maybe that is the case with mine, but the fact that it flys perfect VNAV and V/S descents with no oscillation leads me to believe it is something more.  I have reached out to Trek from Garmin on this issue, but he has yet to respond.  I have not flown any other long body  airplane that has it installed, yet.  I have flown a J with it installed and it was perfect in all regards, so it may just be a long body issue or a "my airplane" issue.

[Bob - S50]

Might be on to something there Don.  Our J is perfect.  Some of the Bonanza people are seeing problems similar to yours and from what I hear Garmin is close to knowing what the issue is.  Sounded like a software update may eventually fix the problem for them and hopefully for you too.

[khedrei]

What is your model? An M? Arent the J and M both mid bodies?

I have a K. I hope I dont have any issues. 

[Niko182]

5 hours ago, donkaye said:

The AFMS covers Emergency Procedures and Abnormal Procedures better than any of the Bendix/King manuals ever did.  I've attached a partial copy of the Table of Contents.  The unit also monitors itself, and with the "Smart Servos", when they disconnect, they totally disconnect unlike the old type servos.

While I'm glad I upgraded to the GFC 500, I have to say I am only about 85% satisfied with it.  While most functions like flying level work very well, one of the most important ones doesn't in my airplane.   It won't fly a stable approach, but instead mildly oscillates down either the ILS or GPS approaches with vertical guidance.  I've been hesitant to talk to Garmin about it because  they helped me so much getting it working when I first had it installed.  Most of the time it's an installation issue, and maybe that is the case with mine, but the fact that it flys perfect VNAV and V/S descents with no oscillation leads me to believe it is something more.  I have reached out to Trek from Garmin on this issue, but he has yet to respond.  I have not flown any other long body  airplane that has it installed, yet.  I have flown a J with it installed and it was perfect in all regards, so it may just be a long body issue or a "my airplane" issue.

If you would be interested, i will have the gfc500 installed in my eagle in about 2 months. Ill let you know the outcome of the project. I think behind the firewall, the eagle and bravo are practically the same. Im also in socal so about an hour and 40 minutes down from you.

Edited December 6, 2019 by Niko182

[donkaye]

1 hour ago, khedrei said:

What is your model? An M? Arent the J and M both mid bodies?

I have a K. I hope I dont have any issues. 

The J is a mid body.  I haven't flown a K Model with a KFC 500. Mine is an M and is a long body.

[donkaye]

2 minutes ago, Niko182 said:

If you would be interested, i will have the gfc500 installed in my eagle in about 2 months. Ill let you know the outcome of the project. I think behind the firewall, the eagle and bravo are practically the same. Im also in socal so about an hour and 40 minutes down from you.

I would definitely like to see how yours behaves, as the Eagle and Bravo are in the long body category.  Let me know when it's done.

[LANCECASPER]

22 hours ago, donkaye said:

 I have flown a J with it installed and it was perfect in all regards, so it may just be a long body issue or a "my airplane" issue.

 

I don't think it's just your airplane, some Beechcraft owners are also experiencing some of the same symptoms:

https://www.beechtalk.com/forums/viewtopic.php?f=21&t=175326

[flyingcheesehead]

On 11/10/2019 at 2:09 PM, donkaye said:

For those who are flying or have flown the big iron (@Bob-S50), I'd be interested in knowing how the YD is handled in those aircraft.  With the Citation, I just remember turning it on right after takeoff and off before landing.

It's not "big iron" but I fly a TBM 850 and a TBM 900 for work (the "big French Mooneys") with the G1000 and GFC 700. For us, it's two positive rates, gear up, 115 KIAS, flaps up and YD on. We use manual electric pitch and rudder trim to set trims for takeoff prior to taxi, but the GFC700 does have the ability to trim the rudder, so the before-takeoff adjustment of rudder trim is the only one we do manually. We generally disengage the YD on final at the 500-foot callout.

FWIW, I'm not particularly impressed with the YD on the GFC700. In bumpy air, it seems to constantly lag behind the actual motion of the airplane, as if it's just reacting too slowly to yaw. It also gets easily overwhelmed when the gear doesn't retract or extend perfectly evenly. However, having read the experiences of those here, I plan to include YD in my eventual GFC 500 purchase.

Edited January 12, 2020 by flyingcheesehead

[Marauder]

I'm still looking for a long body airplane that has had the GFC 500 installed.  After the installation issue I had with the pitch trim in my airplane, I don't think Garmin believes there is an issue with the GFC 500 on approach in the long body Mooney.   I've checked cable tensions and even spent 3 hours checking the spring cable tension on the elevator, which is independent of the autopilot.  I have reached out with no success.  What do you think?  Here is a video I made yesterday in smooth air.  VNAV works perfectly as does V/S with no oscillations, but approaches, that is another story as you can see.
 

Don - I’m not familiar enough with who is controlling the autopilot, the G5 or G500 Txi. Any chance the G5 is causing this oscillation? Something is providing the GFC500 the attitude information. Wonder if the shop you’re working with can toss in another G5 (if it’s driving the AP). You need to start eliminating factors.

It doesn’t looking like a binding issue or something with the airframe. I would expect a binding or tension issue to be erratic. Not rhythmic like this is.


Sent from my iPad using Tapatalk Pro

[donkaye]

17 minutes ago, Marauder said:

 

Don - I’m not familiar enough with who is controlling the autopilot, the G5 or G500 Txi. Any chance the G5 is causing this oscillation? Something is providing the GFC500 the attitude information. Wonder if the shop you’re working with can toss in another G5 (if it’s driving the AP). You need to start eliminating factors.

It doesn’t looking like a binding issue or something with the airframe. I would expect a binding or tension issue to be erratic. Not rhythmic like this is.


Sent from my iPad using Tapatalk Pro

 

The autopilot software is in the G5.  I think some of the settings need to be changed, but after Trek Lawler gave his input here on Mooney Space regarding changing settings, there is no way I am touching them.  What doesn't make sense is that there is no oscillation in VNAV or V/S descents, but there is with approaches.

[ArtVandelay]

2 hours ago, donkaye said:

The autopilot software is in the G5.  I think some of the settings need to be changed, but after Trek Lawler gave his input here on Mooney Space regarding changing settings, there is no way I am touching them.  What doesn't make sense is that there is no oscillation in VNAV or V/S descents, but there is with approaches.

I would go through the settings while recording it and post that, maybe someone with a working installation can compare it with their settings? Didn’t a MS volunteer their plane for the certification, I would try talking to him. I can’t believe Garmin can’t fix this. I can trim my airplane and get a smoother ride with no autopilot. For grins I would try to disable the TXI and GPS (pull the circuit breakers) and other non G5/GFC boxes that may share the interfaces (CAN,RS232...), put AP in heading mode and altitude hold, or does it work in cruise and just not with approaches?

[MIm20c]

5 hours ago, donkaye said:

I'm still looking for a long body airplane that has had the GFC 500 installed.  After the installation issue I had with the pitch trim in my airplane, I don't think Garmin believes there is an issue with the GFC 500 on approach in the long body Mooney.   I've checked cable tensions and even spent 3 hours checking the spring cable tension on the elevator, which is independent of the autopilot.  I have reached out to them with no success.  What do you think?  Here is a video I made yesterday in smooth air.  VNAV works perfectly as does V/S with no oscillations, but approaches, that is another story as you can see.

 

To be honest we’ve been dragging our feet on the GFC upgrade since November.  The 225 flys the plane so well it’s hard to spend the money to get the performance shown above.  Finally planning on installing the new AP next month, I really hope Garmin gets their software tweaked before then. 

[Mooney in Oz]

5 hours ago, donkaye said:

I don't think Garmin believes there is an issue with the GFC 500 on approach in the long body Mooney.

Hello Don.

Don't know if this means anything; I noticed -1000 is constantly displayed in the VS window whilst the VSI is fluctuating between 200 fpm and 1000 fpm. 

[Bob - S50]

Don,

I notice you are flying final at 100 - 110 KIAS.  How does it do if you fly final at something closer to your VFR final speeds?  Something like 80 KIAS or so?