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Claude Troncy

Strange behavior with elevator after landing.

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Bonjour,

 

I noticed that sometimes after landing the elevator doesn't work proprely. (737NGX 800 Steam )
For example when moving the joystick it doesn't stay in it's position and return to the center. It is particulary true when in abutment .
 
This only happens on the ground after landing, and if I do a touch and go, as soon as the plane took off, the joystick behavior is again correct.
I made somme test after disabling all my addons. The only way to recover a correct behavior is to stop the engines and then as soon as the ground power is connected, the joystick (elevator)works without problem.
 
Now I find that it only occurs if I use the APP mode during approach. If I only fly the approach manually without APP mode I have no problem at all.
So what do you think ?
 
Cheers
Claude 

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Bonjour Claude,

 

I'm using the NGX in FSX-SE and I don't see this problem. It sounds to me like the autopilot is not disconnecting properly after landing. Shutting down the engines will remove hydraulic pressure so disconnect the autopilot.

 

After landing using the autopilot, when do you disconnect it and how do you disconnect it? Using the Z key will not work properly and you need to assign a key to the AP disconnect button using the CDU menu.

 

Landing manually is much more fun anyway and much more usual.

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Merci Kevin for the answer,

 

In fact I have Z assigned to a button on my joystick, but FSX doesn't receive the event as in FSX control no key is set for the Autopilot Master (On/Off).

In the CDU I have the key Z assign to the disengage bar.

When in approach I want to switch off the A/P, I hit the button on my joystick, I then can hear the horn, and by hitting the button again, I then stop the alarm saying that the A/P is off.

 

Is it the correct way to manage the disconnect ?

Cheers

Claude

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Merci Kevin for the answer,

 

In fact I have Z assigned to a button on my joystick, but FSX doesn't receive the event as in FSX control no key is set for the Autopilot Master (On/Off).

In the CDU I have the key Z assign to the disengage bar.

When in approach I want to switch off the A/P, I hit the button on my joystick, I then can hear the horn, and by hitting the button again, I then stop the alarm saying that the A/P is off.

 

Is it the correct way to manage the disconnect ?

Cheers

Claude

Claude,

 

You need to be in APP mode to land with the A/P engaged, but it isn't the cause of your problem.

 

The disengage bar is not the normal way to disconnect the A/P. The menu has an assignment for A/P DISENGAGE SWITCH and that is what you should assign a key to. This is equivalent to pressing the A/P disconnect button on the control yoke.

 

Operating the disengage bar will disconnect the A/P and cause the alarm to sound, but operating it again will not silence the alarm. It justs puts the disengage bar back up. Are you sure Z is not still assigned in FSX to autopilot master switch? Pressing that twice will cancel the alarm (by reengaging the AP).

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I think my problem is more related to the APP mode than the A/P itself.

APP mode has no effect without the AP.

 

Heed Kevin's advice.

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Thanks Kevin and Kyle,

 

Sorry I made a mistake, in fact Z was not assigned to "disengage bar" but to" A/P disengage switch".

 

I am sure that Z is not assigned to the autopilot master switch in FSX.

So I think my config is OK.

 

If I do an approach without hitting the APP mode, and disengage AP juste before the glideslope capture then from this point I am in manual mode and after landing the elevator is OK.
Now if I hit the APP mode, the AP follow the LOC and GS, then I disconnect AP at 1000 ft and continue in manual, then I have the problem with the elevator.

So APP mod used... problem, APP mode not used ... no problem.

 

I find a other way to stop the strange behavior of the ailerons after landing. I just recycle the 2 FD and everything becomes OK

 

Cheers

Claude 

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I know I've seen this in another thread, but can't remember which. It leads me to believe that this is normal behavior for the NG. (But of course, i could be wrong)

 

The auto flight system is not completely un coupling, until you hit the AP switch on the yoke, i.e. your Z button.

Then shut down the FD as well. You don't need them on the ground.

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Can you be more specific about what you're claiming the problem is here? 

 

Yes I can ! Sorry if I am not clear, english is not my mother tongue.

I am not claiming anything I just want to understand.

 

Sometimes, I noticed that after landing the stick in the aircraft (pitch axe) doesn't follow the joystick with a tendency to return to the neutral position.

It is only a problem if we immediately takeoff again, without stopping the engines, as the elevator come back to the neutral position during the rotation.

As soon as the plane is airborne the behavior is again correct.

 

After making tests and narrowing the problem I found that it only occurs if the APP mode was used during the approach. I also noticed that recycling the FD when on the ground cure the problem

.

When you have time, and if you want, could you make an approach in APP mode (Autoland for example), then disconnect AP and AT, and see if the stick in the plane follow the joystick when on the ground.

Just push and pull it at the max. In my case the aileron and the aircraft stick move in the neutral position, as if the software bypasses my controller inputs.

I hope my explaination is more clear.

 

Claude

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Bonjour Kyle,

 

Did you have time to have a look ?

It is not a big deal, and I noticed it accidentaly. I am not 100% sure it is a problem with the product.

 

My experience in software developpment showed me that sometimes a strange behavior, without consequence, can hide a bug somewhere.

 

That is the only reason which made me report the problem.

Regards

Claude

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Bonjour

 

For information:

As I was in contact with  PMDG technical support for a sdk question, I took the opportunity to talk about the elevator problem.

They are aware of the issue and it has been submitted to the team to look at for a future update. 

Cheers

Claude

 

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