Issue, or maybe a bug?

[nckd 0]

     Tonight on a flight from MHTG to MUCC, I was nearing my top of descent when the autopilot went completely haywire, I was away from the computer when it occured. Basically the auto pilot put the plane into a sharp 60 degree bank, going around in circles which resulted in a stall. So I disengaged the auto pilot and manually brought the plane back up to FL300. When I was back to altitude the A/P wouldn't work, it wouldn't turn on, and when It did I had the heading hold selected and the VNAV and RNAV both disabled. But the plane still kept putting inself into a sharp bank no matter what the heading I had set was. And then after that it simply would not engage at all. The only way to finish the flight was by manual flying it and controlling speed myself. Could this be a bug or something?

Thanks

[netshadoe 144]

Do you have any active failures? 

 

Do you have service based failures on and is there a failure? 

 

NGX simulates failures.  You can actively set them.  Service based failures happen over time.  You can even break stuff by not flying the plane properly (there is a thread somewhere around here about someone manually pushing the elevator while the AP was on and broke the AP system that controls the elevator).

 

Did you check to make sure your hardware was not the culprit (a bad controller sends "spikes" to FSX and causes the AP to disengage or not engage at all)?

 

Is your system up to the task of flying the NGX? (Issues have been caused by not enough horsepower)

 

Are you using a 3rd party weather program? (Some cause the S-Turn issue...search for it)

 

Many factors can cause your problem.  The NGX has been out for years...I highly doubt it's a bug.

[pcubine 143]

It's not a bug but is probably operator error. Let me tell you how these types of problems happen. One day I was flying the NGX on one computer and looking at this forum on the second computer, I saw a post I started to reply to. The only problem was I started typing the reply on the keyboard that is connected to the FSX computer. It didn't take long to realize the mistake. I switched to the correct keyboard and finished the post. When I looked at the monitor with the NGX on it, it was out of control almost ready to stall at FL310 and off course. Once back under control I looked at the post and one of the first words contained the letter A which is the key command that I use to disconnect the A/P. Just an example of the hundreds of possibilities of how a plane can seemingly  go nuts out of nowhere.

[kevinh 409]

It sounds very much like the NGX realistic autopilot engagement simulation. It's possible to mishandle engagement and shear the autopilot connection to the flight controls (something necessary to be able to do in real aircraft in case of an autopilot malfunction).

 

Clearing failures in the CDU should fix it.

 

Certainly not a bug.

[scandinavian13 5,192]

 

 

Could this be a bug or something?

 

Sounds like you may have trim axes assigned, or hardware out of calibration. Might this be the case?

 

The AP not re-engaging could be related to this as the others mentioned.

 

Full names in the forum, please.

[ALF1 15]

Just a thought--I have disabled all the keyboard controls of any autopilot function. I control the autopilot either through the MCP in the virtual cockpit or the GoFlight MCP hardware. Both always concur and operation of one is simultaneusly done on the other.

 

One thing I noticed the other day is that if the Control Wheel Steering feature is used too harshly you will effectively break something in the autopilot system, and the only way to fix it is in the failures in the CDU.

 

And to the OP, did both autopilots fail ? did you try system B ? Did you reset both flight directors on ?

 

Proper operation of the Autopilot and Flight Director System is one of the most difficult and thorough steps in this airplane. If there is any doubt whatsoever in how to use it with confidence you really have to study the system hard.

 

 

Alberto Ferracuti