Space Vehicle Physics

I put up a job posting for this, but I've only had 1 hit and I can't meet the (fully justified) pricetag, so I'm trying to roll my own here. I'm knee deep in the vehicle code, and [re]learning an awful lot about vectors and matrixes, and just plain learning alot about the physics of rotation (angular momentum, torque, etc).

I'm trying to create a space vehicle, based on the helicopter vehicle code for the auto-leveling, and I'm doing OK. I feel like I'm really close here. I've stripped out everything to do with gravity and hover jets and drag; my current problem is to get it to turn the way I want. Here's some pertinent code for reference:

void SpaceVehicle::updateForces(F32 /*dt*/)
{
   MatrixF currPosMat;
   mRigid.getTransform(&currPosMat);
   mRigid.atRest = false;

   Point3F massCenter;
   currPosMat.mulP(mDataBlock->massCenter,&massCenter);

   // xv, yv, and zv are the components of the velocity of the ship.
   // They are pulled out of the current position matrix.
   Point3F xv,yv,zv;
   currPosMat.getColumn(0,&xv);
   currPosMat.getColumn(1,&yv);
   currPosMat.getColumn(2,&zv);
   
   // Calculate the speed
   F32 speed = mRigid.linVelocity.len(); 

   Point3F force  = Point3F(0, 0, 0);
   Point3F torque = Point3F(0, 0, 0);

...

   // Steering
   Point2F steering;
   steering.x = mSteering.x / mDataBlock->maxSteeringAngle;
   steering.x *= mFabs(steering.x);
   steering.y = mSteering.y / mDataBlock->maxSteeringAngle;
   steering.y *= mFabs(steering.y);
   
   // Pitch
   torque -= xv * steering.y * mDataBlock->steeringForce;
    //torque -= Point3F(steering.y * mDataBlock->steeringForce, 0, 0); //Mine
   
   // Yaw
   torque -= Point3F(0, 0, steering.x * mDataBlock->steeringForce); //Mine
   //torque -= zv * steering.x * mDataBlock->steeringForce;

   mRigid.force  = force;
   mRigid.torque = torque;
}

The part I'm focussing on right now is in the Steering, Pitch, and Yaw section. The first five lines in Steering are pretty much unchanged from FlyingVehicle. It's where they are converted to Torque that I'm getting messed up. What I need is for the ship to rotate about the Z axis independently of it's pitch; if it's nosed down I want it to stay that way. For pitch, I want it to only move up or down, independent of the rotation. Basically, I want it to do it's pitch movement and then do it's yaw. Or, put another way, I want the vehicle to always face more or less Up on the +Z world axis.

So I changed the torque for yaw about to generate a twist always around the Z axis, and that seems to work OK. The original, if I understand it correctly, uses the zv (column 2 from the position matrix), and it rotates around its local Z axis, not the world Z axis. For pitch, I want the opposite; I want it to rotate around the objects' X axis, not the world X axis, so I left it alone (although I put in some sample code for the world X that doesn't work either).

Can anybody help me out here, or at least explain what I'm doing wrong? Right now the ship twists like nuts until it's heeled over 90 degrees, at which point pitching and yawing are one and the same.

If I can get some help here, I promise to release my code as a [badly needed] SpaceVehicle resource when it's done. I also have some questions about making the vehicle stop turning correctly, and to make it turn 180 to it's current velocity, which I may be able to figure out if I can get this to work, maybe not.

Thanks for any help!