The excitation of a submarine hull by the propeller through ﬂuctuating ﬂuid and shaft forces is investigated. The forces are due primarily to the operation of the propeller in a non-uniform wake and occur in the low frequency range. The resulting propeller pressure ﬁeld can be represented by dipoles which are normal to and along the propeller axis, with the origin at the propeller hub. The hub forces act in the opposite direction to the ﬂuid forces and are modiﬁed in transmission to the thrust block. Both ﬂuid and shaft forces excite vibration of the hull. The axisymmetric vibration associated with accordion modes is a powerful source of sound radiation, so this work focuses on the effect of the axial propeller forces. A simpliﬁed axisymmetric model of a submarine hull has been developed using the ﬁnite element method to represent the behaviour of the structure and the boundary element method to represent the properties of the ﬂuid domain. The model includes a rigid conical section at the aft end of the pressure hull to represent the free-ﬂood structure that supports the aft propeller shaft bearing. This is connected to a dynamic model of the pressure hull itself. It is shown that the conical tail section plays an important role in hull excitation through the ﬂuid. A resonance changer can be used to attenuate the vibration transmission through the propeller shaft, but not the excitation via the ﬂuid. In this paper it is shown how the overall performance of the resonance changer is inﬂuenced by the ﬂuid forces.