A method is described that predicts the kinetic response of a circulating-water-cooled and -moderated reactor to large changes in reactivity. This response is displayed in the form of time histories of power, peak fuel plate temperature, energy, reactivity, and period. The validity of the method is verified by the agreement of calculated and experimental data when it is applied directly to the SPERT-IV reactor. The general applicability and usefulness of the method are illustrated by the analysis of the Air Force Nuclear Engineering Test Reactor. A comparison with SPERT-IV, a parametric study, and an accident evaluation are shown as sample results.