PMDG--737 VNAV DOES NOT ENGAGAE ANYMORE

[Paul12 2]

Since a couple of months VNAV does not angage anymore.

Any idea what the reason could be

Thanks

Paul12

[threexgreen 3,135]

The reason is likely how you set up the aircraft which prevents VNAV from engaging according to real world logic of the systems. Have you changed something in operating the plane? Are you doing anything differently than before? I don't know of any bug in the NGX that would prevent VNAV engagement and there was no update to the product/nothing was changed from the developer's side, which is why it's probably user related.

In any case, we need some more information. In what situation does it not engage? How did you set up the aircraft?

[Bob Scott 7,716]

Most likely your elevator axis is not centered and you have not configured the 737 to disable real-world autopilot connection behavior.

[trisho0 23]

I had similar problem in FSX. I flew from SLLP El Alto to SLCB Cochabamba with PMDG 737 and suddenly disengaged VNAV and the plane lost control. I saw a warning light "Stab Out Of Trim". What happened?

https://drive.google.com/file/d/1tnyWF5v5SV4VQUtAhmrpOb5Nqkdks0Bt/view?usp=sharing

Patricio

[MarkJHarris 128]

Nice video. I can see you're flying about in the low speed warning zone. Had that once when an F/O tried to expedite climb at ATC request with the pitch wheel. Autopilot disengaged the moment it started flashing. I took control and smoothly sorted it but he was a bolshy sod and needed a lesson as he was ignoring my advise. No danger whatsoever I might add. I'd not let him get that far.