Flight control issue

[gilflo]

Hi guys

I have flight controls issue on stock wings. Here is a screen where you see an aircraft built for Eve. it is balanced properly CL being a little bit behind CG. The tank behind with its speed brakes is for retrograde braking and acts like a pendulum for atmosphere entry in prograde while the front shield protects the whole ship. Then between 30 and 10km I eject all and the plane flies by itself but if you look at the screen you can see that pitch is up and stab and ailerons have moved the wrong side (moving down when pitch indicator is up), they are inverted and i think it's because when the tank is behind the aircraft the CG of the whole thing is behind the CL. 

So when i launch my plane in space when coming back to Kerbin, as soon as it is release from the tank, flight controls are inverted.  You can see there is a remote control unit on the tank and if you select "control from here" that solves the pitch issue when you release you craft from the tank, but the ailerons are still inverted.

Inactivating the flight controls have no effect on issue

Have you experienced this inversion when launching a plane on top of rockets?

And what is the purpose of the tab "deploy direction" = normal or inverted? Is it to use the ailerons as flaps or is it to invert the ailerons in flight ? Because whatever is the setting i never succeed to invert in flight, that would have solved my issue

I just succeed to invert one time by selecting "inverted" in the VAB, but i was not able to do it twice! bank left on the roll indicator and the right aileron should be down and it is up

Here is the screen

If you have answers that would be great because i have been searching for a few days....

 

 

Edited June 16, 2016 by gilflo

[bewing]

The control direction of surfaces is determined during flight, by where the CoM is at that moment. If the CoM of the entire vessel is in front of the surfaces, then they deflect in one direction. If the CoM is behind the surfaces, then they deflect the other way. So the fact that you have all this other stuff attached to the plane is affecting the CoM (moving it way back), and that is flipping your control surfaces while you are trying to test them.

Try placing just the airplane part on the runway, and see if the surfaces work correctly then. If they do, then you will have to trust that they will work properly at Eve. But the rig that you are using to test the thing on right now is influencing your results.

[gilflo]

Yes all the surfaces work the right way when plane is alone on the runway and i agree that when the stuff is attached to the plane, the COM is behind allthe surfaces and they work opposite way. I tested that, on ground and in flight.

But in flight, once all the stuff is ejected, we have a normal plane, like the one on the ground, with the COM in front of all the surfaces but the flight controls stay inverted, as the COM was still behind the surfaces and that is the issue I tested.

I was thinking it was a stock issue, but I had exactly the same issue with the same plane using B9 Aerospace wings, the last version updated by CZYRNM

Edited June 17, 2016 by gilflo

[bewing]

They stay inverted??!? Ack! Sorry, I guess I didn't read your initial post closely enough.

The deploy thing can be used for flaps, or it can be used in other situations to force a control surface to "full on". Inverted forces it to "full reverse". But you basically can't control the surface anymore when "deploy" is active, so that won't help you.

The only other possibility for dealing with inverted controls is the "authority" slider in the context menu, which may be the answer to your problem. Or it may just make things worse.  If you set it to -100, that makes the control surface work in the opposite direction from what the editor sets by default. But you can get some spooky effects if you have a surface that controls more than one thing -- both pitch and roll, for example. So you may also have to disable some axes on some control surfaces.

I pretty much always launch planes on top of rockets. But my planes are all canard designs. So after they come off the top of the rockets, the canards are still at the front and the controls all still work the same way as they did during launch. So that's no help for your situation.

 

[gilflo]

Thank's that could help, specially the sliders "authority" and 2 ailerons ,one for pitch only, one for roll only and I will try the -100 setting on the pitch aileron

But i think it's a mod issue because i launch a plane the same way with only a few mods and after separation of the tank the flights controls were moving the right way....

So i am going to search the mod that  is making this issue!!

[Corona688]

I've built entire stages backwards to get fairings out of the way and yes, it will make you click 'control from here' or 'invert' or what have you every single time.

[gilflo]

Do you think a mod that is no used with the aircraft for which I have an issue can make such an issue happened ?

 

[bewing]

Definitely.

[gilflo]

I found the mod that make this control invert: it is Deflection control.