A guidance, navigation, and control engineer designs, manufactures, and tests aircraft and other vehicles. Your duties span research and development, analysis, design, and manufacturing. As a GNC engineer, you are an aerospace engineer with responsibilities that include examining design proposals for financial and structural feasibility, overseeing the design and manufacturing system operations, and running tests to determine safety and performance. You manage quality control, look for issues with designs and final products, and determine what solutions are safe and effective. You must understand and apply concepts like propulsion and flight mechanics, aerodynamics, and thermodynamics when designing and building vehicles.