Unlike x,y,z the angles pitch,yaw,roll are interdependent.
You can't tell much from just one of them.
When is the vehicle upside down?
I would suggest checking which way its Y+ axis is pointing.
Consider this:
This transforms the vector 0,1,0 (the Y+ direction) from vehicle local space to world space.
Now check the resulting TFormedY(). If this is positive then the vehicle Y+ axis
is pointing more or less upward. If the value is negative then it is pointing downward.
You can't tell much from just one of them.
When is the vehicle upside down?
I would suggest checking which way its Y+ axis is pointing.
Consider this:
TFormVector 0,1,0, vehicle, 0
This transforms the vector 0,1,0 (the Y+ direction) from vehicle local space to world space.
Now check the resulting TFormedY(). If this is positive then the vehicle Y+ axis
is pointing more or less upward. If the value is negative then it is pointing downward.