As a member of the SDSU Rocket Project (Solid-Fuel Rocket Team), myself and 3 other members were assigned the task of designing a hybrid rocket motor. We were required to use gaseous oxygen as the oxidizer, solid acrylic as the fuel, and a standard 53 mm convergent-divergent nozzle to accelerate the hot exhaust out of the combustion chamber. It was also mandatory for this design to guarantee a safety factor of 5. To meet the specifications and regulations for this motor, we calculated the internal pressure and temperature of the combustion chamber, given that the gaseous oxygen would be flowing at a pressure of 60 psi. In addition to which, we had to calculate the hoop stress on the cylindrical acrylic fuel chamber to ensure that the apparatus would not explode during the reaction. As a further safety precaution, we decided to encase the entire acrylic cylinder in an aluminum casing; this is set up in case the solid acrylic melts away from the baseplate at extreme temperatures. To prevent leakage, we made a 3/8 NPT hole for the oxygen inlet on the anterior baseplate, and an O-ring gland for a 1/16 O-ring on the posterior baseplate. We used 4 threaded rods to compress the motor between the two baseplates to properly secure the entire system. Detailed SolidWorks models of the motor can be viewed in the images below.