ABSTRACT When disconnected, the drilling riser (even without buoancy modules) can collide with different parts of & moonpool and the floating rig itself. The collision may result in severe damage of the telescopic joint, and extra bending stresses. Calculations were made to find out the maximum movement (upward and lateral) of the disconnected riser as a function of the initial, vertical force applied to the riser. Using the same approach, bending stresses due to rig heave with a riser, connected to the wellhead, are being investigated.