From some US posts it sounds like Garmin have problems with the GFC500 and especially the servos, and a total recall of the servos is coming up.
Surprising given that they made a big thing out of them being brushless.
Can confirm. One of our club planes has the GFC500 and we do indeed have constant issues with them.
But it’s exactly the servos that were hyped so much. No wear. Will last eternally. And so on.
AP brain is also dissappointing for me, if a bit off-topic.
Tried the vnav many times on a PA28 archer, and never succeeded to capture a descent path in convective weather, oscillating between 0 and -1800fpm. On the collins 3000 (in a CJ1+ jet), which is much older with less software, it has always worked flawlessly, intercepting vnav path from vvi or vvp with triple the IAS of a PA28.
On the PA28 you have to activate vnav at least 1 minutes before catching, and it’s not always working…
I am absolutely staggered about how widespread this issue is, yet everybody says this if a fantastic product, and yeah rip out your old King box and put this in. It’s like a medieval crusade… It illuminates a lot of what goes on in avionics, partly because most owners are in-warranty and have to maintain their dealer relationship. Same old story. So much stuff I hear, with instructions to not tell anybody because [the dealer] will cut them off.
Yes; oscillation seems a common fault and – as always, and usually wrongly – it gets blamed on loose bridle cables. It is likely to be crap config for the aircraft type, or software bugs.
You had a G500 on a CJ1?
The servos should not have a wear issue because they use stepping motors, and a non-wearing gearbox is a) not much needed with steppers, due to low motor rpm and b) is easy to do anyway (the King servos rarely wear out the gears).
Peter wrote:
I am absolutely staggered about how widespread this issue is, yet everybody says this if a fantastic product, and yeah rip out your old King box and put this in. It’s like a medieval crusade…
Peter, I think that is more of a “swap one crap with another”, and many had bad experience with legacy A/P as well – as you know not many mechanics could service the legacy A/P in Europe, while for Garmin you still have a chance of a replacement/fix, in many cases free of charge.
Last I heard about the GFC500 failures is that the actual motor is OK, but the circuit board is not, although it is all rumours as you know.
Yes; all true, to varying degrees.
On the old boxes we suffer due to most people who knew what a resistor was having been ex RAF / ex national AF, and as these retire the “expertise” (I would not call knowing what a resistor is as “expertise”) disappears. A stupid tragedy really since these boxes are simple and the maintenance manuals with wonderfully detailed material are freely available. I have a ~30GB collection on a private site but would very much like any contributions. Garmin publish almost nothing of any use, at any level.
The motor should run for ever. Steppers are amazing. I once looked at developing an STC for rebuilding the King servos with a brushless motor but didn’t get around to it. Also the market is continually shrinking as the world is taken over by, guess who, Garmin…
Garmin had a manufacturing problem on a batch of servos and issued a service bulletin. They also then offered an exchange programme on certain part numbers regardless of whether they’d failed or not, with a five-year period. Effectively they’ve provided a five-year warranty. Seems to me like a proactive company helping their customers! Shame Honeywell weren’t so helpful with the KFC225 issues.
https://support.garmin.com/en-US/aviation/faq/2tVToAbyOO2EVxW6GmNTj6
I am happy with the GFC500, despite the problems I am reading mine is quite precise and no oscilations.
On the other hand, the GTN650Xi when back to the manufacturer, the touchscreen stopped working, despite the GPS still working. The problem is that I could change frequencies on the G3X, but load approaches no way.
