Quick Quaternion Question

I trying to use quaternions for the first time in our 3d flight game. I am wondering if when I have the plane oriented out in the world such that it is no longer along the x-, y-, or z-axis, and I need to pitch the plane around it own right axes by ''fDegPitch'', can I just call the regular function rotateX(quat, fDegPitch), which rotates the quaternion around the x-axis by ''fDegPitch''. Thanks