Senior Manufacturing Engineer, Solid Rocket Motors

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.

We are seeking a Senior Manufacturing Engineer to lead key manufacturing processes for solid rocket motors (SRM) supporting Castelion's hypersonic strike weapons, including the Blackbeard program. This role focuses on developing, optimizing, qualifying, and executing production processes for propellant mixing and casting, motor cases, liners/insulators, nozzles, and final motor integration.

You will drive process improvements, support the transition from prototype and research builds to scalable high-rate production, and ensure high quality, safety, and efficiency. Working closely with Design, Propulsion, Automation & Controls, Quality, and Test teams, you will contribute to new product introduction, continuous improvement, and facility ramp-up at our manufacturing sites.

• Lead development and optimization of assigned SRM manufacturing processes, including propellant formulation/mixing, vacuum casting, filament winding, liner/insulator application, nozzle assembly, curing, and integration.
• Drive Design for Manufacturability (DFM), Design for Assembly (DFA), PFMEA, control plans, and statistical process control (SPC) to improve yield, reduce cycle time, and lower cost.
• Support new product introduction (NPI) and design change implementation by providing manufacturing input and executing process qualifications.
• Perform root-cause analysis and lead corrective/preventive actions for process issues and defects.
• Integrate NDE methods (ultrasonic, CT, shearography, thermography) and in-process inspection into production workflows.
• Collaborate with Automation & Controls to implement robotics, vision systems, and digital tools (MES, data analytics) for improved efficiency and traceability.
• Author and maintain work instructions, process documentation, and training materials; mentor junior manufacturing engineers.
• Ensure compliance with energetic materials handling, DoD 4145.26-M, ATF regulations, ITAR, and explosive safety standards.
• Support equipment qualification, process validation, and production ramp at the Midland, TX facility and the Project Ranger campus in New Mexico.
• Interface with suppliers on materials, tooling, and equipment to resolve issues and improve incoming quality.

• Bachelor's or advanced degree in aerospace engineering, manufacturing engineering, materials engineering, mechanical engineering or physics.
• 5+ years of manufacturing engineering experience, including at least 3+ years hands‑on work with solid rocket motors, energetic materials processing, or complex assembly in aerospace or defense.

• Bachelor's or Master's degree in Manufacturing Engineering, Mechanical Engineering, Chemical Engineering, Aerospace Engineering, Materials Science, or related field.

• 6–10+ years of manufacturing engineering experience, including at least 3+ years hands‑on work with solid rocket motors, energetic materials processing, or complex assembly in aerospace or defense.
• Demonstrated success developing and scaling manufacturing processes from prototype to low‑rate or rate production.

• Strong hands‑on experience with propellant mixing/casting, composite filament winding or layup, liner/insulator processing, and propulsion hardware assembly.
• Proficiency in CAD (Solid Works or NX), GD&T, tooling/fixture design, and process documentation.
• Familiarity with industrial automation, PLCs, robotics, or MES systems is a plus.
• Working knowledge of energetic materials safety and hazardous process manufacturing.

• Experience in fast‑paced environments such as aerospace startups.
• Background supporting high‑rate composite manufacturing, insensitive munitions…