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Colin wrote: ↑Sun Apr 14, 2019 5:29 am When my FADEC was failing recently I had a racing prop. All sorts of fun stuff, but apparently it is a circuit board issue, not a mechanical issue.

Colin, did you (or can you) post more details about the ECU failure? Which part(s) of the ECU system failed: ECU A, ECU B, and/or voter? How did this creat the racing (over speed) prop? Thanks!

Don wrote: ↑Sun Apr 14, 2019 6:36 pm Just out of curiosity, are the propellers on a DA 42 counter rotating?

Mercedes (for Austro engines) doesn't build engines that turn the wrong direction, although theoretically Austro could have designed a different gearbox that turns a prop in the opposite direction.

The good news is that with such long wings, it's really hard to tell any difference in performance when shutting down the left "critical" engine vs. right engine in flight.

Thanks Dave,
I figured since the MB engines required a RPM reduction gearbox for the props, they might have used that design opportunity to reverse the direction of one propeller. I have a 36,000 pound boat with twin diesel engines and one of the gearboxes does reverse the rotation of the prop so that they counter rotate. Just was wondering if the DA 42 did the same.

I will write it up in more detail eventually. I had ECU A and ECU B fail on the RH engine departing KOWD a few weeks ago. The engine registered overspeed for six tenths of a second, I believe, but it was an insane number (4,600 RPM?), and I don't think it was real. I reduced power on that side, flew the pattern and landed. We restarted. Their appeared to be nothing wrong (although you can't clear the errors without the laptop). We did a full power run up on the ground. The engine seemed fine. It was cold that morning and I figured that might be the issue.

We took off, very alert for anything amiss. Everything seemed fine. We flew 2.5hrs down to KLNS and the plane was flawless. On the ground there a shop downloaded the errors, cleared them, and said they couldn't get the problem to repeat. We took off for home, the failure alerts popped on again, so I elected to return and left it with that shop.

It is now in the able hands of Glenn Lawler who has replaced the ECU A and says that has fixed the problem. It has yet to get back in the air because it's in annual and we're replacing the cooling lines.

I could be wrong but I see much more issues like this in Austro than in CD, at least these days.

Colin, thanks for the additional information! Sounds like the complete story is still developing. Would value additional updates in the future when there's more to tell.

Hi Colin,

What do you mean by replaced ECU A ?

RPM is measured at 2 sensors and sent to 2 independent computers, trying to understand what caused the problem.

Just wanted to add my experience to this post...

I was flying VFR into an airfield in Germany when my prop governor decided to give up life. I shut down the RH engine and landed OEI without any problem (beside higher blood pressure and pulse than usual). When I was on the ground I took this video for the maintenance shop.

[youtube]https://youtu.be/xxi2j97A3q0 [/youtube]

Maintenance and MT confirmed the governor defect. Was happy that I was alone and not sitting in a DA40.

Wilfried wrote: ↑Sat Apr 20, 2019 8:57 pm Just wanted to add my experience to this post...

I was flying VFR into an airfield in Germany when my prop governor decided to give up life. I shut down the RH engine and landed OEI without any problem (beside higher blood pressure and pulse than usual). When I was on the ground I took this video for the maintenance shop.

[youtube]https://youtu.be/xxi2j97A3q0 [/youtube]

Maintenance and MT confirmed the governor defect. Was happy that I was alone and not sitting in a DA40.

No joy with the video. You Tube says not available.

Can you expand on the symptoms and what choices you had other than shutting it down?

I can't recall if anyone has had to shut down the Lyc on their DA40. No doubt it has happened but I've not heard of it. But seeing the DA42 having several it's no wonder they put two engines on it. ;-)