Hi everyone,

First of all, the combination of PMDG's 747 and P3D V4 is what we have all been waiting for.  At least on my system (Windows 10, GTX 970, i7, SSD drives, etc.) is just about silky smooth.  Great job PMDG!

With any complicated simulator, there's going to be bugs or operator error.  In my case I did two flights yesterday and twice I got the dreaded STAB TRIM UNSCHD EICAS message.  When I disconnected the autopilot the trim was indeed not in the desired position since it ran away nose up.  Never saw this in the FSX version, but seeing this in the P3D V4 version.  Any ideas? Bug or a problem on my end?

Thanks,

George

Hello !

I had this problem two times in P3D V3. I identified the cause has loading the Mooney before the flight and inadvertently engaging the autopilot using my joystick hotkey. I did not notice that during take off because the aircraft was well trimmed and I set the autopilot soon, but the problem showed after during the flight. Some kind of ghost autopilot was trying to do its thing over the PMDG bird. After landing, I re loaded the Mooney - without exiting the simulator -, pressed the key and heard the autopilot disconnect.

Voilà ...

I've had this same message on the last couple of flights in P3D v3 however I've never loaded into another aircraft first - always selected the 747 from the menu and loaded straight in there.

When the message appears, the Trim is at 0.  If I try to correct, the AP disconnects, I get the trim to a point where the aircraft isn't rocking then re-engage the AP but it simply moves right back to 0.

If I leave it, the message will eventually disappear but the Trim has now set to higher than the green band (usually around 10) where it sits for a period before moving back towards 0 and displaying the message again.

I've tried the FCOM procedures and got no joy from those.

No-one any clues or hints as to where the issue may be coming from?

22 minutes ago, Trevor Hannant said:

No-one any clues or hints as to where the issue may be coming from?

Do you have a hardware trim axis? Any hardware trim/up down buttons that may be inadvertently triggered by conflicting key commands?

Hi Kyle.

Don't have an axis assigned to elevator trim, just two buttons on the yoke which are only assigned to trim up and down directly.

Rather bizarrely, took the Queen up for a test flight just now and it's no longer exhibiting the behaviour that it has done on the previous 5 or 6 flights.  Will keep an eye on it and post back here if that changes...