Spaceplane SAS Problem

[Gamer217]

I need help with my spaceplane, whenever I toggle the SAS or press F for that matter the ailerons set themselves up to roll the craft causing it to crash. Any help is appreciated. Here is the craft:

[Jason Patterson]

If you toggle SAS on the runway does it lock the flaps upward? Have you actually seen the flaps going up or does it nose up sharply as if that is what had happened? Does it only happen after you've used the rocket for a while, or does it happen immediately after liftoff too? (It looks like your CoM may shift behind your CoL as the fuel drains, since the plane is so lightweight.)

Other thoughts:

Have you got a joystick/controller pad plugged in that could be sending phantom signals to the plane?

Have you accidentally set the trim upward on the flaps by pressing alt-up repeatedly (fat fingering it, presumably) while playing?

[sal_vager]

There's not a lot of control authority on that craft, I think you need some canards

[RocketPilot573]

I think your control surfaces are so close to the center of mass that they just don't know what way to move and thus sending the plane out of control.