Pitch oscillation

[jroode]

HI,
I have the D100 intalled with the AP74. Example: If I am at 6500 feet and set the AP to ALT 7500 feet, then the aircarft will climb past 7,500 feet (to +/- 7,800 feet) then start descending. It will then descend below 7,500 feet (to +/- 7,200 feet) and then start climbing again. This can carry on for a while unitl it settles on 7,500. Is there anyway to fix this?

Thanks
Jan

 

[dynonsupport]

First, if you're hitting the high or low IAS limits, that can cause some issues on altitude capture. You might try using a lower vertical speed limit as well, and playing with the sensitivity (small moves) setting. If it's wallowing, you might click it up a couple of notches. If there's any slop in the servo to elevator linkage, as well, that may cause issues.

All that said, pitch performance is something that we'll be improving in one of our next couple of releases.

 

[DBRV10]

Jan

I have the same experience at random times, can be perfect for ages but a bit of mountain wave seems to set it off or some minor turbulence. it will shoot right past the set point.

I am providing feedback to Dynon about this issue and I wonder if its airframe related, ie a fast aircraft with a very sensitive and authoritive elevator. Which I have relative to some others I assume.

Just to help Dynon and myself understand what is your aircraft?

I have a Vans RV-10.

I am looking forward to future updates ......

Thanks

DB

 

[jroode]

Hi DB,

I have a Jabiru 430. Cruise speed 105knots. So not very fast PLease keep me informed on any feedback from Dynon as I must say, it is very annoying this oscillation.

Thanks
Jan
South-Africa

 

[DBRV10]

We had one of them before the RV-10.

Your J430 should TAS 120 or even a bit more with the new engines. 105 is not right, suggest you talk to the local folks over there about that!

 

[jroode]

HI David,

Yes top the green line is 120KIAS, but I normally just cruize at 105 KIAS. I have been told that one should not really cruise regularly at below the 120 KIAS (max green), as it can actually damage the engine. Not sure what your thoughts are on this?

 

[JR]

Cruse in J230/J430 is around 120 @ 2850rpm
Running engine BELOW this by much will cause serious problems, could be advising not to sit on one rpm for long while its New

There are hundreds here running in Aus - 120 kts all the time. Jabiru are happier with 2900 than 2600.

 

[dynonsupport]

For purposes of the AP and the initial question, what is your "max airspeed" in the AP menu set to?

 

[DBRV10]

ours is set at the VNE less a bit 190kts from memory.........but I could be wrong. The Min Speed is the stall +30%

 

[jroode]

It is set to 120 KIAS

 

[dynonsupport]

And what are your sensitivity and fpm settings?

 

[DBRV10]

pitch about 17, fpm300

 

[jroode]

Not sure what it is set at - what are the ideal settings? I am on holiday at the moment and not at my plane, so I can't check. If you can assist me in what the correct settings should be to avoid this problem, I can adjust it when I am back.

Thanks
Jan

 

[jroode]

How do I check sensitivity and fpm settings?

 

[dynonsupport]

It's under SETUP>AP. Check out the installation manual on our site for more details.