A high power and high power density Ion Cyclotron Resonance Frequency (ICRF) antenna is being designed for the Joint European Torus (JET). 3D finite element models of the antenna and neighbouring components (poloidal limiters, the main horizontal port and vessel double wall) have been developed. The flow pattern of halo currents and the distribution of induced currents during disruptions have been determined with electromagnetic static and transient analyses, imposing loads (rate and amplitude of the poloidal and radial field change and halo current sources) consistent with those observed in the operation of JET. These currents have subsequently been used to estimate the electromechanical loads due to the interaction with the externally imposed magnetic field. Stress, displacements, forces and torques have been calculated in all parts of the antenna subassembly.