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Garmin autopilot issue

Dugaru

Well Known Member
Having previously remarked on how much I liked my new Garmin autopilot, (http://www.vansairforce.com/community/showthread.php?t=148437), I should probably report on a recent development.

I had a G5, a GMC 307, and GSA 28 pitch and roll servos installed last month.

After my earlier post, and about 3 weeks/13 flight hours after the installation, my GSA 28 pitch servo failed, with the error message "servo hardware fault" displayed on the G5.

Communication with Garmin revealed that they "have discovered an issue with some servos and presently have a stop ship on all servos until the problem is resolved."

The Garmin rep I corresponded with has not yet heard when replacement servos will be available to ship.

Garmin has expressed confidence in my remaining (roll) servo and has told me that they see no reason to replace it under warranty.

Needless to say, I was anticipating a better experience with my new Garmin gear. I'm looking forward to Garmin remedying this problem quickly and fairly.
 
Hello Doug,

We are very sorry that you had to deal with a servo fault. Several have been reported recently.

The GSA 28 servo has been a very robust design with thousands shipped since its release in 2013. We did, however, identify an issue that has affected some servos.

The servos that have faulted with a self determined "hardware fault" have all been relatively new in service (like yours) and have all been replaced under the 2 year warranty.

As it turns out, there were not any actual failures that would have prevented the servo from operating correctly, but the issue causes the servo to erroneously detect and report an internal fault, and of course refuse to allow the autopilot to be engaged.

Many internal tests are performed by the servo processor at each power-up and during operation, and the issue causes one of those tests to sometimes fail even when it should not.

After determining the root cause of the issue (which did not require a design change), we stopped shipments to make sure no additional servos with this issue were shipped, but the stop shipment was released yesterday and we are working hard to get caught back up.

We apologize for any inconvenience this has caused.

Thanks,
Steve
 
Steve
I just had a complete Garmin panel installed in my plane by Jesse Saint. That included a complete auto pilot system with 2 GSA28 servos. Will there be a recall or any notification of defect.?
 
Steve
I just had a complete Garmin panel installed in my plane by Jesse Saint. That included a complete auto pilot system with 2 GSA28 servos. Will there be a recall or any notification of defect.?

Hello Tim,

Probably not due to the expected low number of affected units and the fact that the issue doesn't affect servo performance, but let us know if you see this fault and we will take care of you.

BTW - your new RV-9A panel is amazing!

Thanks,
Steve
 
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Hello Tim,

Probably not due to the expected low number of affected units and the fact that the issue doesn't affect servo performance, but let us know if you see this fault and we will take care of you.

Thanks,
Steve

Steve -

Based on the number of failures to date, what % of currently installed units do you expect will be affected? It's 50% in my case (so far), but obviously n=1. :)

Not sure I understand your observation that "the issue doesn't affect servo performance." My servo does not seem to be performing. And it needs to be replaced before the autopilot will work again, correct?

Or, given the nature of the problem, is there some way to get everything working again without replacing the servo? That would be awesome since it would save me the cost, hassle, and downtime of removal & re-installation, etc.

Thanks
Doug
 
Hello Doug,

The "doesn't affect servo performance" statement only applies to servos which are not reporting a fault.

In other words, the issue is not related to the core servo operation, so unless the servo has this issue which causes it to erroneously report a fault (and thus not be usable), servo operation is not affected.

Any servo like yours which is continuously reporting this fault will need to be replaced, and it is probably best to continue to work directly with our customer support group to get any questions you may have answered.

Anyone wishing to discuss a servo with this issue should contact us directly by phone or email shown below.

Thanks,
Steve
 
Doug,

Hang in there, g3xpert and the rest of TeamX will get you fixed up.

Good news is that normally these things are solid as a rock and just work! Mine has performed flawlessly!
 
Steve:

Can you tell us the serial number range of the affected units, and the current failure percentage of the units within that range?

This would give me at least some idea of the future risk that I face with respect to my other servo.

I may be getting conflicting information on that topic. You've stated that there has been a "low number of affected units." On the other hand, Stein Air told my installer that there "has been a rash of servo failures for some reason."

Even if Garmin is unwilling to replace my remaining servo, I need to make my own decision on that, and I don't have any of the data Garmin has. In particular, I don't know the difference (if any) between a "small number" and a "rash."

As I'm sure you can understand, I may have a different risk tolerance than Garmin with respect to replacing my remaining servo -- because I'm flying behind it, and because I may have to deal with the next failure in flight or (as with the pitch servo) far from home.

Depending upon the scope of the problem, I may decide to replace the roll servo even if I simply have to buy the improved version and take a loss on the existing one.

I'm not trying to be combative, and of course I'm happy to hear from you personally, but I do think that this could be a significant safety and operational issue, and that it will be of interest to a lot of people on the forum.

Thanks
Doug
 
I'm not trying to be combative, and of course I'm happy to hear from you personally, but I do think that this could be a significant safety and operational issue, and that it will be of interest to a lot of people on the forum.

Thanks
Doug

Like the rest of us its easy to get spoiled and fall in love with the AP, it makes life so "easy".

But I'm not sure I understand why you think it's a safety issue, if the AP faults it simply disconnects and lets you know about it, so you revert back to good old "hand flying". Inconvenient yes, safety issue.. I don't think so, or it shouldn't be.

I've had the AP do unexpected things at times (usually my fault) but the simple solution is always just disconnect and fly the plane while you sort things out.
 
Since there is no "LIKE" button:

thumbs-up-sign.png
 
But I'm not sure I understand why you think it's a safety issue, if the AP faults it simply disconnects and lets you know about it, so you revert back to good old "hand flying". Inconvenient yes, safety issue.. I don't think so, or it shouldn't be.

A recent trip from MN to FL saw the shear screw on my Dynon pitch servo fail at top of climb leaving MN. I hand flew the rest of the way down and all the way back (IFR plan with a mix of VMC and IMC) . I'm not even sure I would say it was inconvenient - but it sure was fun!
 
auto

I think its good to be informed by other builders and know whats taking place with parts we use in our planes.
Good for Doug bringing this to light I didn't see Steve starting a thread saying there is a problem if Doug had not posted who would have known to be on look out.
Bob
 
Hang in there, g3xpert and the rest of TeamX will get you fixed up.

They just postponed the promised delivery date for my replacement servo -- for the second time. They say it's back-ordered. Latest target: 5/31.

This problem continues to be very frustrating.
 
They just postponed the promised delivery date for my replacement servo -- for the second time. They say it's back-ordered. Latest target: 5/31.

This problem continues to be very frustrating.

Sure it is but speaking for myself, I would rather them get it right than to ship prematurely. Hang in there!
 
My failure mode experience

I had not posted about this because, at first, I had thought I might be the problem somehow.

I have had both servos for my RV-14A fail in this manner and I haven't even left the ground yet. I bought through Stein and have had both replaced. The problem showed up during the installation of my Avionics. First the pitch servo failed and then the roll several weeks later.

The plane is at the airport and I expect first flight soon.

I will say that the response from both Stein and Garmin was terrific. Replacement servos each arrived very quickly.

I'm glad that Garmin has identified the problem.
 
First the pitch servo failed and then the roll several weeks later.

I'm worried I'm in the middle of exactly that scenario.

Garmin has declined to replace my roll servo, arguing that it hasn't failed yet. But I think the real question is whether or not it has a known defect. It's a consecutive serial number with my pitch servo, which did fail, and of course it's precisely the same gadget. N=1, but your experience would suggest they may have a defect in common.

I'd feel much better about this if Garmin could answer some of the questions above, especially concerning the percentage failure rate for these servos. Surely they have that information. So far, the only thing I've heard is there has been "a rash" of failures.

If only 1 in 1000 of these servos goes tango uniform, then whatever, I'll take my chances. But if my roll servo is very likely to go belly up, as yours did, I'd like to replace it now, along with the pitch servo -- rather than have it die at some particularly un-fun time, like when I'm shooting a coupled approach.
 
I'm worried I'm in the middle of exactly that scenario.

Garmin has declined to replace my roll servo, arguing that it hasn't failed yet. But I think the real question is whether or not it has a known defect. It's a consecutive serial number with my pitch servo, which did fail, and of course it's precisely the same gadget. N=1, but your experience would suggest they may have a defect in common.

I'd feel much better about this if Garmin could answer some of the questions above, especially concerning the percentage failure rate for these servos. Surely they have that information. So far, the only thing I've heard is there has been "a rash" of failures.

If only 1 in 1000 of these servos goes tango uniform, then whatever, I'll take my chances. But if my roll servo is very likely to go belly up, as yours did, I'd like to replace it now, along with the pitch servo -- rather than have it die at some particularly un-fun time, like when I'm shooting a coupled approach.

I don't think I have ever seen any manufacturer of experimental aircraft products provide this level of detail on their failure rates....
 
I don't think I have ever seen any manufacturer of experimental aircraft products provide this level of detail on their failure rates....

Since you asked...
The Trio web page has a "mandatory SB" (installing a washer). They state that out of over 3,000 installed servos, they have received 2 reports of a pressed pin backing out.
So some manufacturers do report the statistics.
 
Since you asked...
The Trio web page has a "mandatory SB" (installing a washer). They state that out of over 3,000 installed servos, they have received 2 reports of a pressed pin backing out.
So some manufacturers do report the statistics.

Moreover, the Garmin folks are very active in this forum promoting and supporting their products. I'm obviously okay with that, in fact I think it's great. But given their presence and participation, I don't think it's inappropriate to ask them for information about known defects.

All I'm asking for is the type of info Trio provides above. Garmin must have at least some idea of the % of failed units.
 
I have purchased 3 servos in the last year & I am ready to install them. I feel that garmin should have a recall. Why should I install and wait for failure of a product that garmin knows is defective!
 
Since you asked...
The Trio web page has a "mandatory SB" (installing a washer). They state that out of over 3,000 installed servos, they have received 2 reports of a pressed pin backing out.
So some manufacturers do report the statistics.

I didn't ask but good to know.
 
Moreover, the Garmin folks are very active in this forum promoting and supporting their products. I'm obviously okay with that, in fact I think it's great. But given their presence and participation, I don't think it's inappropriate to ask them for information about known defects.

All I'm asking for is the type of info Trio provides above. Garmin must have at least some idea of the % of failed units.

Have you called Steve and asked him?
 
I have purchased 3 servos in the last year & I am ready to install them. I feel that garmin should have a recall. Why should I install and wait for failure of a product that garmin knows is defective!

Call TeamX and voice your concern. They are good people!
 
Have you called Steve and asked him?

I didn't really see the point, after he declined to state the failure rate publicly here in response to several requests. Telling me personally on the phone would be the same as posting it publicly here, because that's what I would turn around and do.

But who knows? I'll give him a call and report back.

Meanwhile, despite Garmin telling me that they wouldn't have any new servos until 5/31, they apparently hit my card and sent me one yesterday (!). So that's good news. I'm assuming they've now fixed the problem.
 
You may find that developing a relationship with these folks personally can lead to a much better experience.

Didn't need to do that with the guys who built my S-Tec -- but I'm certainly not opposed to the idea.
 
So, in an effort to learn what caused my autopilot to disconnect by itself, I came across this thread. Here's my story...

Yesterday in the final throws of my IFR checkride, during the flight portion (of course) of the test my ap disconnects. I presumed that I hit the trim buttons, so I re-engaged it. After about a couple of minutes it disengages again. This happened several more times and I was unable to complete the exam. As you can imagine, this was somewhat discouraging!

Additionally... After the incomplete exam had ended, I elected to fly the airplane to a friend's airport nearby. Upon departure, on crosswind my oil temperature red lines not once, but twice. Fuel pressure does the same thing. Clearly these were erroneous. It makes me wonder if the seperate occurances were related or not? During the balance of the flight the engine instruments were stable, but the ap kept checking out.

I called support, but this being a weekend day they won't be available until Monday morning. I would really like to know where to begin looking for my fault. I have removed the data log and was wondering if there would be a smoking gun in it?

When one experiences a bad servo, what is the failure? Could this be my problem? Are these problems even related?

I just updated my firmware to version 11.60. Is there a bug in it? Anyone else had a problem with the new firmware?

Is there a problem with another LRU?

Are these issues related in any way?

Any advice would be appreciated.

I am absolutely beside myself. This has never happened before and for it to happen during my checkride was so unlikely!

:confused: CJ
 
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So, in an effort to learn what caused my autopilot to disconnect by itself, I came across this thread. Here's my story...

Yesterday in the final throws of my IFR checkride, during the flight portion (of course) of the test my ap disconnects. I presumed that I hit the trim buttons, so I re-engaged it. After about a couple of minutes it disengages again. This happened several more times and I was unable to complete the exam. As you can imagine, this was somewhat discouraging!

Additionally... After the incomplete exam had ended, I elected to fly the airplane to a friend's airport nearby. Upon departure, on crosswind my oil temperature red lines not once, but twice. Fuel pressure does the same thing. Clearly these were erroneous. It makes me wonder if the seperate occurances were related or not? During the balance of the flight the engine instruments were stable, but the ap kept checking out.

I called support, but this being a weekend day they won't be available until Monday morning. I would really like to know where to begin looking for my fault. I have removed the data log and was wondering if there would be a smoking gun in it?

When one experiences a bad servo, what is the failure? Could this be my problem? Are these problems even related?

I just updated my firmware to version 11.60. Is there a bug in it? Anyone else had a problem with the new firmware?

Is there a problem with another LRU?

Are these issues related in any way?

Any advice would be appreciated.

I am absolutely beside myself. This has never happened before and for it to happen during my checkride was so unlikely!

:confused: CJ

Hello CJ,

Sorry you are having trouble. The first step would be to email us the data log from your SD card for this flight which should tell us something about the reason for the autopilot disconnect.

Thanks,
Steve
 
So, in an effort to learn what caused my autopilot to disconnect by itself, I came across this thread. Here's my story...

Yesterday in the final throws of my IFR checkride, during the flight portion (of course) of the test my ap disconnects. I presumed that I hit the trim buttons, so I re-engaged it. After about a couple of minutes it disengages again. This happened several more times and I was unable to complete the exam. As you can imagine, this was somewhat discouraging!

Seems strange to me that the exam would be discontinued due to an inop AP, I would have thought flying the procedure by hand and working through the problem successfully would be more important than watching the AP fly the airplane.
 
Walt, use of installed equipment needs to be evaluated. If the installed equipment isn't functioning, it can't be evaluated. I have the LOD with the reason on it to show you if you still find it strange. Trust me, it's a thing!

Thanks for your input though!

On a different note, I did look at my data and in the Autopilot State column it has two strange lines of code. If anyone knows what Fail/abnormal disengage/00000004 and Fail/communication fault/00000005 means, I would be interested in knowing.

Steve from Garmin, the data is in your inbox.

Thanks again!

:rolleyes: CJ
 
I would suspect the CAN bus. I had a similar intermittent problem. I ended up redoing all the connections - I found one connection where I had sliced into one of the wires when stripping the outer sheath, and one of the fine wires from the shield was shorting there.
 
Yesterday in the final throws of my IFR checkride, during the flight portion (of course) of the test my ap disconnects. I presumed that I hit the trim buttons, so I re-engaged it. After about a couple of minutes it disengages again. This happened several more times and I was unable to complete the exam. As you can imagine, this was somewhat discouraging!

I was the guy who started this thread about the servo issue. What you describe does not sound like my servo problem, which annunicated with a big black box on the screen.

It does, however, sound like the problem I had just a few weeks ago, after my autopilot had been working correctly for months:

http://www.vansairforce.com/community/showthread.php?t=161284

Did you also get a red "AFCS" failure alert?

I've been logging data religiously since my incident but thus far it's been working without a hitch. I'll be interested to see what you come up with.
 
Well, I got no indication of any failures. No red x's or anything. It just bugged out with the trlple tone.

I will keep you posted with what I discover.

Really looking forward to getting this sorted out!

:confused: CJ
 
On a different note, I did look at my data and in the Autopilot State column it has two strange lines of code. If anyone knows what Fail/abnormal disengage/00000004 and Fail/communication fault/00000005 means, I would be interested in knowing.

Your error message seems to be similar to what was described in this thread:

http://www.vansairforce.com/community/showthread.php?t=157633

So maybe there is a new software problem. On the other hand, I'm running mine from a G5 with a GMC307 panel, so there are a lot of variables that are different between yours and mine. Who knows.

I was able to get mine going again after popping the autopilot circuit breaker and resetting it, and it worked after that, but I haven't been able to fly it much lately.

I am envious of your triple tone! I would love to have an audio warning of the autopilot disconnecting. I get only a little flashing yellow square (and sometimes the AFCS warning) on an attitude indicator that is my backup AI, so an uncommanded disconnect is easy to miss, especially in cruise. I think this is a drawback of a G5/GMC307 installation that appears to have been remedied with the GMC507.

Garmin folks: is there an upgrade path from the 307 to the 507? I think the warning tone would be worth it, although obviously it would need some additional wiring to the audio panel. Or could you do a software upgrade that flashes the whole G5 screen yellow (or something similarly "alarming") when the autopilot disconnects?
 
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