Principal Spacecraft GNC Engineer, Controls

About Firefly Aerospace is a space and defense technology company on a mission to reliably and repeatedly launch, land, and operate space systems from Earth to the Moon and beyond. As the partner of choice for critical space missions, Firefly is the first commercial company to launch a satellite to orbit with 24-hour notice and the first company to achieve a successful Moon landing. Headquartered in north Austin, Texas, Firefly is looking for passionate, hardworking innovators to join our team and help fuel our successful trajectory into space. Summary As a Principal Spacecraft GNC Engineer specializing in controls and autonomy at Firefly, you will design and implement advanced control systems and autonomous flight software for operational spacecraft. In this role, you will develop and tune attitude control software, support hardware-in-the-loop testing and system integration, and provide technical leadership while collaborating with multidisciplinary teams. This position combines advanced control theory, real-time embedded systems development, and hands-on flight operations support while mentoring junior engineers in a fast-paced operational environment. Responsibilities Provide technical direction on system architecture and serve as subject matter expert for spacecraft controlDesign, analyze, and tune spacecraft attitude control software to ensure accurate pointing across all mission phasesOwn design and implementation of control laws for orbital maneuvering and descent and landingDevelop control systems accounting for complex spacecraft dynamics including structural flex modes, propellant slosh, gimbal dynamics, and control structure interactionEstablish technical standards and validation methodologies for control system design, software development, and hardware-in-the-loop testingConduct stability analysis, sensitivity studies, and performance optimization for control systems under nominal and off-nominal conditionsSupport hardware-in-the-loop test campaigns for integrated ADCS systems including control algorithm validation, flight software verification, and system-level performance testingDrive resolution of complex ADCS challenges requiring deep technical expertise and rapid problem-solvingMentor junior engineers in control theory and flight software developmentInterface with cross-discipline teams to integrate control software with spacecraft hardwareServe as an ADCS console operator for spacecraft operations and perform post-mission analysis to improve spacecraft modelsChampion continuous improvement initiatives for ADCS processes, tools, and operational efficiency Qualifications Required Bachelor's degree in aerospace engineering, mechanical engineering, electrical engineering, computer science, or related field8-12 years of experience in spacecraft ADCS systems with significant depth in attitude control system design or flight software developmentAdvanced knowledge of attitude dynamics and control theory, including rotational dynamics, attitude representations, control moment generation, and stability analysisStrong understanding of classical control theory and frequency domain analysis techniquesProficiency in thrust vector control design and interaction with the greater GNC subsystemExpertise in real-time software development using C++ for mission-critical applicationsExperience developing high-fidelity actuator models and attitude control system testbedsProficiency in hardware-in-the-loop testing and requirement verification for mission-critical systemsUnderstanding of software development best practices including version control (Git), code documentation, and testingExcellent communication and presentation skills Desired Master's degree or PhD in aerospace engineering, mechanical engineering, electrical engineering, applied mathematics, or related fieldExperience architecting and implementing control systems for operational spacecraft from development through mission operationsExpertise in advanced control techniques such as nonlinear control methods, optimal control, model predictive control, or adaptive control applied to spacecraft applicationsAdvanced knowledge of state estimation techniques including Kalman filteringAdvanced knowledge of numerical methods for control law tuning, root-solving, and parameter optimizationExperience with modern flight software frameworks and real-time operating systemsSoftware engineering expertise with proficiency in development practices including version control, code review, testing, documentation, and CI/CD workflowsProficiency in Python for scripting, data analysis, and automationWorking knowledge of spacecraft systems and mission operationsProven ability to develop junior engineers while managing technical responsibilitiesTrack record of thought leadership through publications, presentations, or contributions to industry state-of-the-art Firefly offers outstanding benefits for our employees, including generous health, dental and vision plans with low plan deductibles, parental leave, educational reimbursement, short term disability, and flexible PTO options. To conform to U.S. Government space technology export regulations, including the International Traffic in Arms Regulations (ITAR) you must be a U.S. citizen, lawful permanent resident of the U.S., protected individual as defined by 8 U.S.C. 1324b(a)(3), or eligible to obtain the required authorizations from the U.S. Department of State. Firefly Aerospace, Inc. is an Equal Opportunity Employer; employment with Firefly is governed based on merit, competence and qualifications and will not be influenced in any manner by race, color, religion, gender, national origin/ethnicity, veteran status, disability status, age, sexual orientation, gender identity, marital status, mental or physical disability or any other legally protected status