Failure following a software update

[rcostes]

Dear Staff,

I have bought a pre-owned CTLS this year. The preceding owner had bought it brand new with a dual screen Skywiew with Dynon AP installed.
When I bought it, everything was running perfect but the system software had never been updated. The version of the software was 3.XXX
So I decided to update it to the latest version and I directly installed version 6.
Since this update, my AP is not working anymore. I have some permanent ROLL SLIP even on ground during the tests whereas the torque is set to 100%.
On the pitch axis, the AP gives me some wrong trim instructions: When I engage the AP with my airplane trimmed, the Skyview asks me some TRIM NOSE UP. So I trim it up and the alarm disappears but when I disengage the AP, the aircraft is way too much trimmed up!

I don't really understand what is happening. I have done the calibration process several times but it does not change anything. I wonder if it is due to the version skipping of my first update.

Thanks for your replies!

Blue skies

 

[Dynon]

So you're newer software has some new annunciations that your old one didn't, including better slip and trim annunciations.

The Flight Design control system is also "sprung" with return springs on the roll axis, and so it's not entirely surprising that you get slips, even at full torque, after some deflection, though it shouldn't happen at complete neutral. You'd need to check with flight design on what the exact expectations should be there. Have you tried the roll axis in flight?

On the trim indication, though it's possible that your servo has an issue, it's also important to note that the trim feature is not designed to exactly nullify all trim forces; it's designed to let you know when you're so far out of trim that the servo is losing its control authority over the aircraft. Also, it's best to make small trim adjustments when you see the annunciation in the direction indicated, and then, from there, wait a few seconds and see if the trim annunciation goes away.

Finally, 6.0 introduces a lot of new AP behaviors. Technically speaking, Flight Design actually hasn't approved 6.0, and really, if you're following their guidance, you should be running 5.1 with their approved settings. But, with 6.0, you really should use the updated autopilot in-flight tuning guide to dial in the AP performance on your aircraft type.

 

[rcostes]

Hello,

I don't think these are better annunciations because before my update, my AP was working, meaning it was maintaining altitudes and tracks. Since my update, my AP is not able to maintain any track even any level flight anymore! So I can't even perform the in-flight tuning process...

How could I install version 5.1 now?

Thanks for your replies

Blue skies

 

[Dynon]

What exact variant/year/model is your aircraft, and where is it located?

 

[rcostes]

Hello,

Sorry for the delay but I was on holidays...
My CTLS has been sold brand new in France in October 2011. I am still in France.
The model is a CTLS 472,5 KG class and it has been delivered with a Dual SV-D700 system with an integrated transponder coupled to a Garmin 695 on the central panel.
The CTLS distributors has just told me that the AP problem may be caused by the internal servo's fuse but it does not sound right to me. What do you think?

Thanks for your answers!

Rémi

 

[Dynon]

There's no "fuse" in that sense. There IS a shear pin that is designed to yield under some circumstances (mechanical failure of the servo). This would essentially separate the arm from the rest of the servo, but would cause the AP to not seemingly work at all, and wouldnt' give you slips alerts. Since this is a manufactured aircraft, ideally Flight Design should be able to provide some support here. Can you follow up with an email to our support staff at support at dynonavionics.com so that we can work with you one-on-one? (provide a link to this post too)