About the job Structural Dynamics Engineer 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. Structural Dynamics Engineer As a Structural Dynamics Engineer at Castelion, you will own the structural dynamics methodology used across our missile and aerospace systems. You will develop high-fidelity analytical models, validate them through testing, and provide the engineering insight that drives design decisions from concept through flight. You'll work across structures, propulsion, avionics, flight test, manufacturing, and test engineering to ensure our vehicles survive some of the harshest dynamic environments imaginable. This role is ideal for someone who enjoys combining analysis with real hardware testing and wants to influence vehicle architecture from day one. Responsibilities Develop and continually improve Castelion's structural dynamics and loads analysis methodologies Perform modal, random vibration, shock, transient, and frequency response analyses for flight hardware Generate structural dynamics models and simulation results that directly influence critical engineering decisions Define dynamic test strategies spanning component, subsystem, and full vehicle qualification Correlate analytical models with test data and continually improve model fidelity Partner closely with design, manufacturing, propulsion, avionics, and flight test teams to optimize hardware performance Develop automated analysis tools and workflows to improve engineering efficiency Support qualification, acceptance, environmental, and flight testing activities Drive technical decisions in a fast-paced, highly collaborative development environment Basic Qualifications Bachelor's degree in Mechanical Engineering, Aerospace Engineering, Structural Engineering, or a related field (or equivalent experience) 3+ years of experience performing structural dynamics, loads, or vibration analysis Experience with finite element modeling using

FEMAP , NASTRAN

, or equivalent FEA tools Strong experience using MATLAB and/or Python for engineering analysis and data processing Experience performing modal, vibration, shock, or transient dynamic analyses Strong understanding of structural mechanics, dynamics, and aerospace loads environments Preferred Skills and Experience Master's degree in Mechanical or Aerospace Engineering Experience supporting development of missile, launch vehicle, spacecraft, or other aerospace systems Experience planning and executing structural dynamics testing including modal surveys and vibration testing Experience correlating analytical models with physical test results Experience developing custom engineering analysis tools or APIs (FEMAP API, Python, MATLAB, etc.) Familiarity with qualification standards including MIL-STD and NASA dynamic testing requirements Demonstrated technical leadership through complete product development programs Experience working in a rapid hardware development 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. 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.