To utilize propulsion energy effectively, it is necessary to develop technology that can enable variable thrust by altering the area of the nozzle throat in a solid rocket motor in real time. In this study, an aerospike-shaped pintle nozzle, an altitude compensation nozzle technology, was designed to improve the performance compared to that of the existing pintle nozzles. Pressure fluctuations caused by the movement of the pintle led to the hysteresis of the combustion chamber pressure, which sharply increased the pintle load. Depending on the design conditions of the actuator, a load that was approximately 2.5 times larger than that in the normal state could be applied to the actuator. Additionally, cold flow tests were conducted under static conditions to verify the reliability of the design code for the actuator load prediction results. Moreover, firing tests were performed to verify the reliability of the internal ballistic simulation code. Finally, factors related to the thermal expansion of the pintle and the deformation of the nozzle throat, which caused changes in the nozzle throat area during combustion, were identified and mathematically modeled. Additional firing tests were conducted to validate the updated numerical model. Before the model was updated, a pressure difference occurred at most three times or more between the performance prediction model and the firing test results, but the performance prediction error was reduced when the modified numerical analysis was used. If the present results are applied to a guided missile system, the high-altitude operation performance will improve and precision thrust control will become possible, enabling flexible guided missile system operation. •An aerospike pintle nozzle for real-time rocket thrust control was developed.•Combustion chamber pressure hysteresis occurs due to pintle movement.•Factors that change the nozzle throat area were identified.•Dynamic performance prediction was achieved, and an analytic method was suggested.