As a GNC/AOCS Engineer - Avionics at Spire, you will operate as part of a technical team who maintains responsibility across the full lifecycle of the Spire GNC product and its subcomponents. The GNC team interfaces directly with many engineering groups to conduct R&D, design, manufacturing, and operations activities, ultimately ensuring all current and future spacecraft systems satisfy their mission. Ideal candidates will embrace the commercialization of nanosatellite systems and adapt to low-cost, fast-paced systems design, development, and implementation methodologies that set Spire apart from our competition. In this fast-paced environment, the design to launch cycle is measured in weeks and months, not years! What You’ll Do: Design, evaluate, select, qualify and implement flight sensors, including magnetometers, sun sensors, inertial measurement devices, Earth sensors, and/or star trackers. Design, evaluate, select, qualify and implement flight actuators, including magnetic torque elements, reaction wheels, and propulsion systems. Design, implement and maintain simulation models for GNC subcomponents in our 6-DOF simulation environment. Technical ownership of current and future GNC avionics peripherals, supporting troubleshooting, design and updates to improve reliability and performance. Working closely with cross-functional teams, including hardware, software, and systems engineers, to integrate avionics solutions into the larger platform. Develop component qualification and acceptance processes and be hands-on in laboratory and manufacturing environments. Key Skills: Experience with flight sensors for spacecraft attitude determination/estimation. Experience with actuators, including actuator sizing, modelling, design and integration. A solid foundation in spacecraft attitude dynamics and control algorithms, with emphasis sensor ingestions and actuator command calculation. Experience working hands-on with HW and familiarity with 'hardware-in-the-loop` simulation. Experience developing software using C/Python. Have experience or familiarity with the Linux development environment. Have experience working with external engineering contractors. Preferred Skills: Experience writing flight software. Experience designing and/or implementing Kalman filters and feedback control for attitude estimation. Experience with C or C++ development for embedded systems. Experience with spacecraft design. Experience with spacecraft assembly, integration, and testing. Experience with spacecraft operations and maintenance. Experience identifying and resolving system anomalies. Experience creating and maintaining integration and test campaigns for attitude determination and control systems, including hardware and software. Spire operates a hybrid work model, and this position will require you to work a minimum of three days per week in the office. Access to US export-controlled software and/or technology may be required for this role. If needed, Spire will arrange the necessary licenses—this is not something candidates need to have before applying.. LI-MI