Senior Structures & Composites Engineer; Rocket Motor Cases) Torrance, CA; Rio Rancho, NM Leviathan Engineering

• Long Range Strike Systems

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, ownership, and excellence are decisive advantages - and we're building a world-class team to turn bold ideas into real capability.

This is a rare opportunity to join at an early stage, where you'll have significant ownership, collaborate with exceptional teammates, and make a direct, measurable impact on our mission and the future of the company - regardless of your function.

We are seeking a Senior Structures & Composites Engineer to design and deliver high-performance rocket motor cases for Castelion's long-range hypersonic strike vehicles. This role is critical to enabling lightweight, high-strength propulsion structures capable of withstanding extreme pressure and thermal environments. You will work hands‑on with multidisciplinary engineering teams to design, analyze, build, and validate composite and metallic motor case structures in a fast-paced, hardware-driven environment.

Responsibilities

• Design and develop rocket motor case structures, including composite over wrapped pressure vessels (COPVs) and filament-wound composite cases
• Lead the architecture and detailed design of motor cases, including load paths, interfaces, domes, bosses, and attachment features
• Perform structural analysis of pressure vessels under internal pressure, thermal loads, and dynamic environments to ensure performance and reliability
• Develop and analyze composite layups, fiber orientations, and manufacturing approaches to optimize strength, stiffness, and mass
• Work closely with propulsion, materials, manufacturing, and test teams to ensure seamless integration of motor cases with propulsion systems
• Support material selection, processing, and characterization for composite and high-temperature materials
• Conduct failure analysis and root cause investigations, driving design improvements and risk reduction
• Define and execute qualification and environmental test plans, including pressure testing, proof/burst testing, and vibration testing
• Support prototyping, fabrication, and hardware bring-up, including troubleshooting manufacturing and structural performance issues
• Optimize designs for mass efficiency, manufacturability, and operational reliability
• Mentor junior engineers and contribute to best practices in composite and pressure vessel design
• 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 structural and composite design for aerospace or high-performance pressure vessel applications
• Strong background in composite materials, including filament winding, laminate theory, and failure criteria (e.g., Tsai-Wu, Hashin)
• Experience designing pressure vessels, COPVs, or rocket motor cases for high-pressure applications
• Proficiency in structural analysis tools (e.g., ANSYS, Abaqus, NASTRAN, or equivalent)
• Familiarity with manufacturing processes for composites, including winding, curing, and inspection methods (e.g., NDI/NDT)
• Experience with proof/burst testing and structural validation of pressure vessels
• Experience with hardware build, test, and troubleshooting in a lab or production environment
• Strong problem‑solving mindset, thriving in a fast‑paced, hardware‑rich, high test cadence environment

Castelion offers a generous benefits package. Please refer to the bottom of our Careers page for more details.

Other Duties

Please note this job description is not designed to cover or contain a comprehensive listing of activities, duties or responsibilities that are…