Sierra Engineering and Software Inc, formerly doing business as Johnson Rockets Inc, provides cradle-to-grave design, analysis, and testing of propulsion systems. The firm specializes in the design of cooling chambers, injectors, igniters, nozzles, and other rocket engine components. Sierra utilizes SolidWorks to generate 3D models and drawings, and has extensive experience with both standard and non-standard manufacturing processes, and associated costs for metals, exotics, and composites. Sierra Engineering has experience designing, analyzing, and testing the following types of combustion chamber cooling methods and devices: Fuel Film Cooling, Ox Film Cooling, Transpiration Cooling, Barrier Cooling, Duct Cooling, Regenerative Cooling, Self Cooled (Ablative & Radiation).