The vibration and stability of a spinning disk under space-fixed tangential edge loads are studied. Both conservative and follower loads are considered. Finite Fourier transform method is employed to discretize the equation of motion. Sensitivity analysis is then performed up to the second order to predict the effects of various Fourier components of the edge loads on the eigensolutions of the spinning disk. In the case when the tangential edge load is uniform and of the follower type, the first order derivatives of the eigenvalues are real. If the direction of the edge load is opposite to the sense of the disk rotation, then all the forward traveling modes will be destabilized, and all the backward and reflected waves will be stabilized. When the uniform edge load is conservative, the first order derivatives are always zero, while the second order derivatives are generally purely imaginary. When the conservative edge load is of the form fk cos ku, it is predicted that the modal interaction between two non-reflected waves is always of the veering type. On the other hand, the modal interaction between one non-reflected wave and one reflected wave is always of the merging type.