Wing control surface and Tail

[kornon]

So im having this problem i built the craft up and before taking off i check the winglet thingies ( control surfaces) on the wings and tail, the things that will give the plain control, and the ones on the tail point up but then the ones on the wings point down, hope u know what i mean its like they are inverted can someone help? thanks

[kornon]

one thing i noticed is that the roll works fine, when i roll the winglet things go the right directions it seems to be only when i wanna go up or down that this happens wth?? this is a plane btw yeah

[Flowz0r]

It's supposed to be like that, imagine the air streaming over and around your plane while looking at it from the side.

The control surfaces in the front push your nose up, while the ones in the back push your tail down so the whole thing starts pointing up.

[kornon]

i dont think u understand what im saying. the horizontal part of the tail they point up when u take off, ass should the ones on the back the wings, to give the aircraft lift, but the problem is that when i press S to go up the ons on the wings point down while the ones on the tail wings point up which isnt supposed to be l;ike that. i have a picture but the only way this forum lets me upload an image is through a URL i dont get why i cant upload a pic from my computer

[Flowz0r]

Still sounds exactly how it's supposed to be.

You could upload your picture here http://imgur.com/ and post the URL.

[kornon]

here it is, see what i mean they should both be pointing upward

Edited July 12, 2013 by kornon

[kornon]

any thoughts

[stupid_chris]

The control surfaces in KSP don't interact with air and the air flow. They just generate a force while in the atmosphere, a bit like RCS generates a force to push your craft around.. This generates the infiniglide bug and this also means that those pesky control surfaces don't actually always turn in the way you would expect to make your plane turn for example.

No matter their orientation, no matter which way they are pointing, the control surfaces will make you turn in the way you're asking them to turn according to the direction you're going and where you're controlling from.

Your problem here is that controls in the game are relative to the CoM. Those wings are probably in front of the CoM, so the game inverts in which direction the control surfaces are pointing, but it still orders them to generate an upward force. It's weird I know, but that's what we get for adding plane physics to a game based off rocket physics. When we get proper aerodynamics, this will get fixed for sure.

[Flowz0r]

Definitely working as intended.

I can't quite recall if the game considers center of lift or mass for this, but control surfaces get inverted if they're behind either one of those. Your center of lift and mass both seem to be between your main wings and the tail wings.

This is exactly how it's supposed to be, and you couldn't get planes to take off properly if it wasn't.

As I explained earlier, the control surfaces on your primary wings point down to lift your nose up, while the ones on your tail point up to push your tail down, causing the entire plane to point upwards which allows your wings to lift you into the air.

[stupid_chris]

Definitely working as intended.

I can't quite recall if the game considers center of lift or mass for this, but control surfaces get inverted if they're behind either one of those. Your center of lift and mass both seem to be between your main wings and the tail wings.

This is exactly how it's supposed to be, and you couldn't get planes to take off properly if it wasn't.

As I explained earlier, the control surfaces on your primary wings point down to lift your nose up, while the ones on your tail point up to push your tail down, causing the entire plane to point upwards which allows your wings to lift you into the air.

The center of mass is relevant to control a plane, just as for rockets. Usual planes tend to have their CoM in front of their CoL though, but that's simply a detail, both work find, and with spaceplanes re-entering the atmosphere it's preferable to have it behind if you don't want to get locked in a spin of death.

[Akinesis]

I agree that the control surfaces on the wings are in front of the CoM. It's the only explanation I have, anyway