Senior Thermal & TPS Integration Engineer

Senior Thermal & TPS Integration Engineer

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.

We are seeking multiple Senior Thermal & TPS Integration Engineers to design and deliver thermal protection solutions for Castelion's long-range hypersonic strike vehicles. These roles are critical to ensuring vehicle survivability and performance in extreme aerothermal environments. You will work hands-on with multidisciplinary engineering teams to design, analyze, build, and validate TPS across the vehicle, including heat shields, control surface protection, and internal thermal insulation systems in a fast-paced, hardware-driven environment.

• Design and develop TPS across the vehicle, including heat shields, acreage TPS, and leading-edge protection systems
• Design TPS for control surfaces, including elevons, seals, and moving interface solutions that maintain performance under thermal and mechanical loads
• Develop internal thermal protection solutions, including insulators, blankets, and standoff systems to protect avionics and structures
• Lead the architecture and integration of TPS with primary structure, mechanisms, and subsystems, including attachment methods, gaps, and strain isolation
• Perform thermal and thermal-structural analyses to ensure performance under extreme aerothermal heating and transient environments
• Work closely with structures, materials, aerothermal, GNC, and manufacturing teams to ensure seamless system integration
• Develop and evaluate materials and configurations, including ceramics, carbon-carbon, ablatives, and insulating materials
• Conduct tolerance analysis and assess thermal expansion, deformation, and interface behavior
• Support prototyping, assembly, and hardware bring-up, including troubleshooting and root cause analysis of TPS performance issues
• Define and execute qualification and environmental test plans, including arc-jet, furnace, and flight testing
• Optimize designs for mass, thermal performance, durability, and manufacturability
• Mentor junior engineers and contribute to best practices in TPS design and integration
• Partner closely with program leadership to make technical trades aligned with mission success

• Bachelor's, Master's, or PhD in Aerospace Engineering, Mechanical Engineering, Materials Science, or related field
• 5+ years of experience in thermal protection system design, analysis, and validation for aerospace or high-temperature applications
• Strong background in aerothermal environments, heat transfer, and high-temperature materials
• Experience designing TPS for flight vehicles, including heat shields, control surfaces, or internal insulation systems
• Familiarity with TPS materials such as ceramics, carbon-carbon, ablatives, and insulating blankets
• Experience with seals, gaps, and interface design in high-temperature, moving or constrained systems
• Proficiency in thermal and structural analysis tools (e.g., ANSYS, MATLAB, or equivalent)
• Experience with high-temperature testing methods (e.g., arc-jet, furnace, or similar)
• Experience with hardware build, test, and troubleshooting in a lab or flight hardware environment
• Strong problem-solving mindset, thriving in a fast-paced, hardware-rich, high flight cadence environment

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.

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