The simplicity of the solid motor and the large number of possible grain burning shapes make solid propellants an interesting option for a rocket engine design. Therefore, the focus of this study is to build a complete model of solid combustion, with a specific burning shape, that simulates the rocket performance. & the stresses and FOS are arrived from analysis and compared with design values. Keywords: Solid Rocket motor, Casing, D6AC, Maraging Steel, Haynes 255, ANSYS, Thermo structural Analysis, Ablative liners 1. Introduction 1In a solid rocket motor (SRM) the propellant consists of one or more pieces mounted directly in the motor case, The selected motors have a combined total impulse of about 30000Ns. For comparison purposes, this would be enough to accelerate a motor cycle to about 400kph (250mph). Because our rocket is much lighter, it will accelerate to about 5500kph (3400mph). At this speed, a marathon race would be finished in less than 30 seconds.