Senior Aerothermal and CFD 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. Role Overview We are seeking a Sr. Aerothermal & CFD Engineer to develop aerodynamic, aerothermal, and fluid dynamic solutions for Castelion's long‑range hypersonic strike vehicles. This role is critical to predicting and optimizing vehicle performance in extreme flight environments, including high‑Mach atmospheric flight and re‑entry regimes. You will work hands‑on with multidisciplinary engineering teams to analyze, model, and validate aerodynamic and thermal behavior using computational and experimental methods in a fast‑paced, hardware‑driven environment. Responsibilities Develop aerodynamic and aerothermal models for hypersonic flight vehicles across a wide range of Mach numbers and flight conditions Perform computational fluid dynamics (CFD) analyses to predict pressure, heating, flow separation, shock interactions, and control surface effectiveness Analyze transient and steady‑state thermal environments to support TPS, structures, propulsion, and subsystem integration Develop and validate aerodynamic databases for simulation, guidance, control, and flight performance analysis Work closely with TPS, structures, propulsion, GNC, and flight sciences teams to ensure seamless integration of aerodynamic and thermal design solutions Support vehicle configuration trades and optimization studies to improve performance, controllability, and thermal survivability Correlate CFD predictions with wind tunnel, arc‑jet, ground test, and flight test data to improve model fidelity Develop tools and workflows for aerodynamic, thermal, and fluid dynamic analysis and automation Support flight test planning and post‑flight data analysis, translating results into system‑level improvements Mentor junior engineers and contribute to best practices in CFD and aerothermal analysis Partner closely with program leadership to make technical trades aligned with mission success Basic Qualifications Bachelor's, Master's, or PhD in Aerospace Engineering, Mechanical Engineering, or related field 5+ years of experience in aerodynamic, aerothermal, or CFD analysis for aerospace or high‑speed flight systems Strong background in compressible fluid dynamics, hypersonic aerodynamics, and heat transfer Experience performing CFD analysis using tools such as STAR-CCM+, Fluent, FUN3D, CFD++, or equivalent Familiarity with turbulence modeling, boundary layer analysis, and high‑temperature gas effects in hypersonic flow regimes Experience generating aerodynamic and aerothermal databases for simulation and flight analysis Familiarity with wind tunnel testing, flight test correlation, or experimental aerothermal methods Experience with scripting and automation tools such as Python or MATLAB for data processing and workflow development Strong problem‑solving mindset, thriving in a fast‑paced, hardware‑rich, high‑flight cadence environment Additional Requirements Willingness to support extended hours or weekend work during critical integration, test, and flight milestones. 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. #J-18808-Ljbffr Next Matter