Aircraft config and question

[Patt737]

Hello

Since our passage under P3D (so PM autopilot) we notice an oscillation of the plane in Roll, only when descending on the glide.

We do not know how to solve this problem.

1) What kind of flying model could we try ?

Do you think it's possible to try PMDG 738 ?
We bought PMDG

2) In PM's aircraft config, there is this line:
Can you tell me how to use it?
What is it useful for?

roll_stability         = 1.088  // 1.16 change it according to your hardware

Thank you for your help and your answers.

Patt.

[Trevor Hale]

Since our passage under P3D (so PM autopilot) we notice an oscillation of the plane in Roll, only when descending on the glide.

I fixed this by turning the "PMautopilot=off" that was project magenta and MCP us the built in flightsim autopilot and it seems to be more stable.  I have no oscillations.

1) What kind of flying model could we try ?

Hard to say, try different ones, but you will need to strip all the panels out remember as most will interfere with the PM software.  Many years ago, when I had a 737 I used the PMDG, I don't know if you still can though.

Do you think it's possible to try PMDG 738 ?
We bought PMDG

2) In PM's aircraft config, there is this line:
Can you tell me how to use it?
What is it useful for?

roll_stability         = 1.088  // 1.16 change it according to your hardware

Thank you for your help and your answers.

Patt.

See here.... CLICK

Described as.... " Stability parameters The pitch, roll and yaw parameters are multipliers on the default stability (damping effect) about the corresponding axis of the airplane. For example, a value of 1.1 increases the damping by 10%. Likewise, a value of 0.9 decreases the damping by 10%. A negative number results in an unstable characteristic about the axis. A positive damping effect is simply a moment in the direction opposite of the rotational velocity. Omission of a parameter will result in the default value of 1.0."
roll_Stability = 1.0 would mean that its a stable aircraft  1.16 would be a 16% increase in stability .80 would be a 20% decrease in stability.

Trev

[Patt737]

Super fast response. 
Thank you .
I will study all this.
Patt

[jackpilot]

All airplanes have a tendency by design to revert to their original position when thrown in another one,
Start a 20 deg roll to the left, bring back the yoke to neutral and the airplane maintains a bank until you turn the yoke to the right to cancel the roll.

In reality the aircraft tends to slowly revert to a wing level position.

BUT in FS this is often exagerated and you constantly have to use yoke inputs to the left to maintain your 20 deg bank.
This is where Roll_stability= xx comes into play

The higher the number, the better the airplane will maintain a steady roll attitude. Too much is no good, you have to try and test to your liking.

[Patt737]

Hello,

Thank you for your answers.

Ok for the PM autopilot on off.

I fixed this by turning the "PMautopilot=off" that was project magenta and MCP us the built in flightsim autopilot and it seems to be more stable.  I have no oscillations.


But where can you find another autopilot ?

We are under p3d and no autopilot for the 738.

Can we install another autopilot for 738 if yes:

Or download it ?

Patt.

[Trevor Hale]

Ok..  That option is in the MCP.INI File  It means use Project Magenta's (Internal MCP Logic) or use the Flightsim (Internal autopilot Logic) for autopilot functions.

The autopilot functions are built into Flightsim (prepared, etc)

Maybe I am confusing you.  You will still run the Project Magenta MCP software, but rather than generating its own Autopilot logic, it will just use the logic inside Flightsim.

Trev

[Patt737]

Ah!
Good news !

Do you know the exact name of the line in mcp ini?

When you say FLIHGTSIM it's also true for p3d?

Patt.

[Bob Reed]

Ah!
Good news !

Do you know the exact name of the line in mcp ini?

When you say FLIHGTSIM it's also true for p3d?

Patt.

Here is the line

[Autopilot]
APProjectMagenta=On

You can see mine is on. Trevor has this turned off.Either way you still run the PM MCP software.
                       

[Patt737]

Hello everyone.

This afternoon, I did a lot of tests, with APProjectMagenta = OFF

It's good for swinging in a roll, the plane is stable on loc and glide.

I find another problem, Autothrottle does not work anymore.

Why ?

Patt

[blueskydriver]

Hi Patt,

Copy-paste your PM MCP.ini file (the text) and let me look at it...

John

[Bob Reed]

Hello everyone.

This afternoon, I did a lot of tests, with APProjectMagenta = OFF

It's good for swinging in a roll, the plane is stable on loc and glide.

I find another problem, Autothrottle does not work anymore.

Why ?

Patt

I ran into this issue once myself. I think the way I fixed it was a fresh reinstall of the PM software. There was something not changing cleanly when you switch. I am thinking about turning PM AP off as well. We will see how it goes. What version of the software are you running?

[Patt737]

We use the mcp 518.

'' There was something changing when you switch ''
I do not understand This line?

Thank you

[Bob Reed]

Between 514 and 516 there was an issue. Did you upgrade from an earlier version? Try a re install and see if that gets rid of the issue... Are you using the PM aircraft?

[Patt737]

Yes we put PM regularly updated.
But we did not know where the problem of oscillations came from.

We use the model 738 pmp3d_v4.
But our version of p3d is p3dv3

Do you think we should try with the model pm738 fsx?

[Bob Reed]

Yes we put PM regularly updated.
But we did not know where the problem of oscillations came from.

We use the model 738 pmp3d_v4.
But our version of p3d is p3dv3

Do you think we should try with the model pm738 fsx?

Yes I think you should switch back as the new model was designed for P3D v4 not 3. There are a few differences in the model. See if that helps your issue.

[Patt737]

Yes I can try again with pm 738 fsx.

But to try to fix the oscillation problem I had installed pm738 fsx
and I had not seen any difference.

Is P3d able to do an autothrottle alone?

Patt

[Bob Reed]

Yes I can try again with pm 738 fsx.

But to try to fix the oscillation problem I had installed pm738 fsx
and I had not seen any difference.

Is P3d able to do an autothrottle alone?

Patt

What happens if you use the stock 73 in P3D v3? Does your AT work?

[Patt737]

 Hello Bob,

What is this '' stock 73'' ?

Thanks

[Bob Reed]

Hello Bob,

What is this '' stock 73'' ?

Thanks

The 737 that comes with P3D v3..

[Patt737]

  It seems to me that there is no native 737 in p3dv3.

  Patt

[navymustang]

Correct - no native 737 for P3D

[Bob Reed]

I thought it was just version 4 that did not come with a 73.. Sorry...

[Patt737]

Hello everyone.


1) if I use APProjectMagenta = On, I have opscillations in roll on the glide

2) If I use APProjectMagenta = Off, the autothrottle does not work anymore but the roll oscillations disappear.

The problem of oscillations in roll seems known for several years.
Many post since years speak of this problem.

I really like PM and I would not buy anything else we use it since the year 2005.

How to use another autotrottle?

Thank you for your help.

Patt.

[blueskydriver]

Patt,

It would be very helpful for you to copy/paste the text from your MCP.ini file. That is how I know all PM software...by looking at .ini files

John

[Patt737]

OK, thanks.

Tonight I start the cockpit and I will make a copy of the ini file of the mcp.

Patt.