Spacecraft GNC Engineer II

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 Spacecraft GNC Engineer at Firefly, you will design, analyze, and operate the GNC systems of operational spacecraft. In this role, you will develop GNC flight and simulation software, perform analyses, and support mission operations while continuing to build breadth across core GNC competencies. This position offers hands-on experience with spacecraft attitude determination and control systems, onboard navigation, sensor and actuator modeling, and real-time mission operations across multiple spacecraft. You will deepen your technical capabilities and refine your desired career trajectory, taking ownership of system elements and software tools as you grow toward a senior GNC role at Firefly. Responsibilities Develop and validate GNC software to ensure successful spacecraft mission executionTune and configure GNC algorithms for all phases of spacecraft flightPerform 6DOF simulation analysis of nominal and dispersed flight profilesDevelop and maintain simulation models for sensors, actuators, and environmental effectsCreate tools to automate workflows, process simulation and flight data, and generate technical reportsConduct stability analysis, sensitivity studies, and hardware-in-the-loop testing of GNC under nominal and off-nominal conditionsInterface with cross-discipline teams to integrate GNC software with spacecraft hardwareServe as a GNC console operator for spacecraft operations and perform post-mission analysis to improve spacecraft modelsAuthor technical documentation and analysis reports that communicate GNC concepts and results to diverse audiencesBuild proficiency across core GNC competencies while contributing to continuous improvement of GNC processes and tools Qualifications Required Bachelor's degree in aerospace engineering, mechanical engineering, electrical engineering, physics, mathematics, computer science, or related field2-5 years of professional experience in spacecraft guidance, navigation, and control, or related technical disciplineUnderstanding of spacecraft orbital mechanics, spacecraft dynamics, state estimation, attitude dynamics, and sensor modelingFamiliarity with numerical simulation techniques, integration methods, and modeling of dynamic systemsExperience with Python for scripting, data analysis, and visualizationExperience with C++ for real-time or flight-critical applicationsUnderstanding of software development best practices including version control (Git), code documentation, and testingStrong written and verbal communication skills Desired Advanced degree (master's or PhD) in aerospace engineering or related field with focus on GNCExperience supporting spacecraft GNC across development, integration, and mission operationsProficiency in C++ for embedded systems or real-time applicationsKnowledge of state estimation techniques including Kalman filtering, sensor fusion, and covariance analysisKnowledge of numerical optimization and targeting methods applied to attitude and translational control designFamiliarity with modern flight software frameworks and real-time operating systemsFamiliarity with CI/CD workflows and automated testing practicesExperience with Linux development environments and command-line toolsExposure to spaceflight mission operations or spacecraft commissioning 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