Hi :)
PFD2 Flight director shows wrong pitch. Sometimes it jumps like a crazy horse, sometimes just shows pitch much higher than it has to be.
PFD1 Flight director works perfectly. Bank on the PFD2 also works perfectly.
Avionics: Avidyne.
Aircraft: Piper Meridian
AutoPilot: S-tec 1500
Questions:
1) Any idea what could it be?
2) What data FD uses to show pitch? Why could it be different on PFD1 and PFD2? I assume it uses airspeed. So, it could be an issue with the second static system. But the airspeed is ok on both PFDs.
Thank you for any ideas and advice.
PS. My maintenance doesn’t answer my :)
PFD1 might use AHRS1 and PFD2 might use AHRS2.
There could be a mismatch.
I’d limit ops to VMC until it is sorted out.
Snoopy wrote:
PFD1 might use AHRS1 and PFD2 might use AHRS2.
There could be a mismatch.I’d limit ops to VMC until it is sorted out.
Switching between ADAHRS 1/2 doesn’t change anything. All the data on both PFD are similar and correct. That’s why I don’t think the issue is about ADAHRS.
A flight director in a standalone instrument is controlled by some analogue signals (voltages) and is easy to debug by measuring these, relative to the MM for the instrument.
In this case I have no idea
Peter wrote:
A flight director in a standalone instrument is controlled by some analogue signals (voltages) and is easy to debug by measuring these, relative to the MM for the instrument.
Given the context, I think the problem is with the attitude indication, not an FD indication.
Airborne_Again wrote:
Given the context, I think the problem is with the attitude indication, not an FD indication.
Yesterday, I switched to alternate static in the air when PFD2 Flight director showed wrong pitch. It started to work properly immediately. So, looks like one of the static ports fails.
But if I had a static port problem I would have wrong altitude and speed indication. Weird :(
Zorge wrote:
Yesterday, I switched to alternate static in the air when PFD2 Flight director showed wrong pitch.
I’m now confused. Do you mean attitude indication or flight director indication? They are very different things and both have indication in pitch (and roll).
Is this perhaps a language issue?
In my experience warranty is your best way out of most glass cockpit issues. What is your warranty position?
WilliamF wrote:
In my experience warranty is your best way out of most glass cockpit issues. What is your warranty position?
I don’t have warranty. But it’s not about the price. I just want to have the issue fixed :)…
It’s getting complicated when your avionics is Avidyne Glass + Garmin NavUnits (GTN650) + s-tec autopilot. Even if you have warranty for Avidyne, they always say: “that’s not our issue”