A propulsion system that is capable of lifting the vehicle and payload to the goal altitude is mandatory for success. At the same time, a propulsion system that minimizes shock and acceleration is desirable. The Propulsion group takes this into account to choose an engine configuration. They are also responsible for trajectory estimates, determination of the minimum liftoff velocity, motor performance testing, and the operation of the launch system. The propulsion group uses various methods of analysis to perform these tasks such as using the RockSim software, static motor firings (as show below), as well as the use of knowledge they have gained in their engineering classes.