Dynon compared to Garmin G3X

[avizer]

Hi There,

I just had my panel upgraded with both Garmin G3X and Dynon Skyview.

I am experiencing several issues with the Dynon. Each worries me but the combination of them leads me to not trusting the Dynon at all.

Reading all about the Dynon, I have no doubt that there is a problem with my system itself as I cant think of any pilot that will accept such level of poor performance. Installer did the calibration twice..

Four Main issues:

1. PFD picture jumps - Even when I am standing still on the ground, my PFD jumps (as if the location changes). I would attribute this to poor GPS location.
2. Heading Error of 5-10 degrees (measured on the runway and on ILS approaches). this might be related to the Magnetometer.
3. When making regular 30-45 bank turns, the FPM is all over the place. when I level off, the FPM will be on the wrong side of the actual flight path.
4. In light aerobatics, Dynon is showing rolls when flying wings level.

 

[avizer]

I will add a couple of attachments on YouTube.

 

[avizer]

Problems in Takeoff run: http://youtu.be/Y4ikDqBJarg
Problems in Aerobatics: http://youtu.be/j0Si6OU0640

 

[dabear]

If your heading is off 5-10 degrees when lined up on the runway then your system was not installed/calibrated correctly. Once its correct, you'll see it aligned correctly.
You shouldn't fly it without getting it correctly installed.

Once the SV tumbles because of acro, you need to fly level for a few seconds, then it will right itself and give you correct readings. Its in the manual and already stated.

In your 2nd video, you don't start off with the SV in level attitude you have it already tumbled. Why?

 

[dynonsupport]

The issue with the Dynon jumping is that you likely aren't using the Dynon GPS like we recommend. The installer hooked it up to a 1Hz GPS instead of the 5Hz GPS that we recommend. If I had to guess, they are using the output from the G3X.

As was said before, if your mag compass calibration was not done well, or if the AHRS was put in a bad location, you'll see heading errors.

Once an AHRS is off, it will stay off until you give it time to stabilize. As Bear mentioned, we need to see the maneuver that first made it wrong in order to see if something is up, not just see it once it has an issue.

 

[dabear]

BTW, if you want to come by my airport, I'll help you with the GPS and the other configurations.

 

[aerofurb]

Installed in an L39 by the looks of it.

 

[lolachampcar]

Ball centered upright or inverted will allow the AHARS to find itself again If video is required, I can provide it.

I beat the living bajesus out of my Dynon system in an MX2 and it works perfectly. The G meter can not keep up but then it was never designed to. Once I got the calibrations correct (direction AND pitot/static - all MY issues) GS and TAS are within a few knots with no wind.

 

[avizer]

Thanks for the inputs. Checked the following:

GPS Source - was not connected properly.
Heading - still problematic, 5-12 deg off. very difficult to find a place for the ADHARS with the 6' limitation. will try to find a different place for it.

 

[dabear]

6' limitation? You could put the ADHARS in the nose baggage compartment.

 

[kaas]

What happens if a steel item goes in that luggage compartment?

 

[dynonsupport]

avizer - Give our tech support call at 425-402-0433 so that we can learn a bit more about install. I think we've been speaking with your tech team, actually.

 

[avizer]

Will call Monday.

Tech team moved the ADHARS to the wing. While more than the 6', the assumption was that the heading issue will be resolved as it is away from any other system.
This was not close to being true. Heading was MUCH worse. accelerometers went completely crazy. the simplest maneuvers cased the Dynon to go crazy.