PMDG 747 A/P

[asanal 32]

In my last three  flight A/P during decent in solid IFR condition disconnected.  

Weather Condition: Solid IFR visibility Zero. Turbulent/ moderate/ severe.

Two flights was in 7000Ft and 1500 lost A/P

Last  flight less then  500ft ,auto land mode. Go around  initiated , and circle landed  with out incident with out A/P

 

My findings: A/P connection  over sensitive and need to calibrate for firm connection .

 

 

 

 

 

[Captain Kevin 586]

Any hardware? You may need to increase your null zones or go into the PMDG simulator settings in the FMC and set it, so the controls don't disengage the autopilot. The reality is if you move the controls, it'll disconnect the autopilot, and if your hardware is sending a spike signal, that's why.

[asanal 32]

Hi, Kevin

Ch Yoke:

Alierons Axis :64 Sensitive Null Zone 36

Elevator Axis: 64 Sensitive Null Zone:36

CH pro Pedal:

Ruder Axis: 64   Null Zone :26

 

"PMDG simulator settings in the FMC and set it, so the controls don't disengage the autopilot."

FMC Simulation 2/18 is the page I should make the changes? If yes what value I should put in?

 

Thanks

 

 

 

 

[Captain Kevin 586]

Page 2 of 10, control input with autopilot on. It's either yes or no. You'll want to select no and see what happens.

[Tabs 2,790]

The AP doesn't have "calibration" - if your hardware spikes past a certain amount of deflection signal, it's going to disconnect, that's it.

[asanal 32]

Hi Kevin, 

I switched to "no". I will take a test flight

Thanks

 

Hi Ryan,

Is there any  hardware deflection signal  protection in AP software?

Thanks

[asanal 32]

Kevin,

Good news. 

1-Switched to "No"

2- Increase the Null Zone, 26

I did not received any AP problem during landing at KSAT, Heavy turbulence, 600 ceiling. 

Thanks again

[Captain Kevin 586]

Sure. Have fun. I think a null zone from 36 to 26 is actually a decrease, though.

[asanal 32]

Yes correct, 

My previous problem solved also,  when I reduced Null Zone from 36,to 26 ,Rudder of plane centered,