Senior Guidance Systems Engineer

About the role

Why Castelion, Why Now

Castelion is moving incredibly fast to develop and deliver advanced defense systems at a time when execution matters more than ever. We believe focus and technical excellence are decisive advantages - and we are building a team that can deliver real capability, not just concepts.

This is a rare opportunity to join at an early stage, where your work will directly shape critical systems, influence major technical decisions, and have immediate, real-world impact.

Senior Guidance Systems Engineer

We are seeking a Senior Guidance Engineer to develop guidance solutions for Castelion's long-range hypersonic strike vehicles. This role is critical in shaping the flight performance of our hypersonic systems from concept through flight tests and operational deployment. You will work hands-on with multidisciplinary engineering teams to design, analyze, characterize, and validate guidance algorithms in a rapid hardware-driven environment.

Responsibilities

Lead the design and optimization of hypersonic flight vehicle guidance methods to maximize performance, stability, and maneuverability in atmospheric and space environments
Conduct trajectory and flight simulations to evaluate guidance system performance, identify improvement opportunities, and validate design decisions
Analyze and enhance the inertial and active guidance of Castelion's long-range hypersonic systems, ensuring robust performance under variable environmental conditions
Work closely with teams in avionics, seeker, flight software, and GNC to ensure seamless vehicle integration
Help define and execute test plans for subscale and full-scale flight tests, translating results into system-level design improvements
Mentor and guide junior engineers in best practices
Partner closely with program leadership to make technical trades aligned with mission success

Basic Qualifications

Bachelor's, Master's, or PhD in Aerospace Engineering or related field
3+ years of experience in guidance system design, analysis, and validation for high-speed vehicles (missiles, rockets, hypersonic glide vehicles, or maneuvering re-entry systems)
Demonstrated ability to field guidance systems for DoD or similar programs
Strong background in trajectory/flight simulation (3DOF and 6DOF) and real-time trajectory generation/optimization methods
Experience with onboard trajectory generation approaches
Familiarity with the application of AI/deep learning to trajectory optimization
Proficiency in flight/trajectory analysis tools such as TAOS, POST, or equivalent
Strong problem-solving mindset, thriving in a fast-paced, hardware-rich, high flight cadence environment

Other Duties

Please note this job description is not designed to cover or contain a comprehensive listing of activities, duties or responsibilities that are required of the employee for this job. Duties, responsibilities and activities may change at any time with or without notice.

Benefits And Perks

All full-time employees are granted meaningful long-term equity, sharing in the company's significant growth trajectory. We offer four (4) weeks of paid time off, ten (10) company-paid holidays, and comprehensive health benefits - including 100% employee-covered medical and strong dependent coverage, along with dental and vision plans. We also provide paid parental leave to support growing families, a $100 monthly fitness stipend to promote health and performance, and onsite EV charging for convenience. In addition, employees enjoy perks like catered meals, company-covered food during high-demand periods, and a fully stocked kitchen to stay fueled throughout the day.

While this position does not currently require a U.S government-issued security clearance, it may in the near future. Therefore, the ability to obtain and maintain a U.S. government–issued security clearance is required. U.S. citizenship is required, as only U.S. citizens are eligible for a security clearance.

Affirmative Action/EEO Statement

Employment with Castelion is governed on the basis of 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.