Kerbal Space Program

What Happens: If you build a rocket with control surface fins for stabilization, and put the command capsule upside down, the SAS will turn the control surfaces in the wrong direction, causing the rocket to spin, rather than preventing it from spinning.

How to Reproduce: The easiest way to do it is to start with a Mk-1 Lander Can and flip it upside down, then attach a fuel tank underneath it (to its top), and a rocket engine under that. Finally, put on some AV-R8 Winglets or Canards. On the launch pad, activate SAS and launch. Rocket will spin. If you force the control surfaces in the other direction, you can make the rocket spin the other way. It will only settle after you either turn SAS off or exit the atmosphere.
Notes: Seems to work with any rocket design. The control surfaces move under user input in the same direction as they would if the command hub were upright. I think they should actually be turning in the opposite direction when the hub is upside down, and this might have something to do with the bug.

Mods: * Uninstalled FAR but kept the craft designs. Should not be affecting the game. * Kerbal Engineer - only used in SPH or VAB

Versions Affected: First determined the cause of the bug in 0.22, but may have experienced it as early as 0.18. I'm not aware of any build in which the bug did not happen.