The Impulse Combustion Excel (ICE) computer program was developed to facilitate and accelerate the design and analysis of subscale rocket engines for use in base-heating tests. Such tests are performed on the ground to obtain data for estimating the heating effects of hot exhaust plumes on the aft regions of full-scale rockets during ascent. The computer program is so named because typically, a base-heating test involves impulse combustion — short-duration (of the order of 100 ms long) hot firing using flight propellants. Heretofore, the design of the subscale engines and base-heating tests has been a difficult, time-consuming, iterative process. ICE can be expected to reduce the testing times and costs and to yield improved designs. ICE can be used to design models to be tested in both wind tunnels and vacuum tanks.