Test 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, 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.  

Test Engineer 

Solid Rocket Motors & Hypersonic Systems – Aerospace & Defense 

Position Overview 

We are seeking a Senior Test Engineer to lead testing activities for solid rocket motors (SRM) and integrated hypersonic strike vehicles at Castelion. This role is responsible for developing and executing test plans for static fire testing, environmental qualification, functional verification, and flight test support. You will work hands-on with propulsion hardware, instrumentation, data acquisition systems, and test infrastructure while ensuring the highest standards of safety, data quality, and mission success. Partnering closely with Propulsion, Manufacturing, Integration & Test, and Design teams, you will drive test readiness for prototype, qualification, and production hardware on aggressive development timelines for programs like Blackbeard. 

Key Outcomes 

• Develop our SRM testing process at our site in Midland, Texas and produce data to help inform SRM design 

• Design and deliver fully qualified test stands to support testing our products 

• Deliver a fully validated testing procedure for our facility in Rio Rancho, New Mexico to enable rapid testing and iteration 

Key Responsibilities 

• Lead the development of comprehensive test plans, procedures, and requirements for SRM static fires, environmental testing (vibration, thermal, shock, humidity), functional checkout, and vehicle-level integration testing. 

• Design, commission, and operate test fixtures, instrumentation setups, and data acquisition systems for thrust, pressure, temperature, vibration, and other critical parameters. 

• Execute and oversee static fire tests, environmental stress screening, and other qualification tests, ensuring safe operations with energetic materials and high-consequence hardware. 

• Perform real-time test monitoring, data reduction, analysis, and reporting; identify anomalies and lead root-cause investigations with cross-functional teams. 

• Support flight test campaigns, including pre-flight checkout, range coordination, telemetry monitoring, and post-flight data analysis. 

• Drive continuous improvement in test processes, safety protocols, and efficiency while integrating automation and digital tools for data capture and analysis. 

• Collaborate with Manufacturing and Propulsion on testability, design-for-test feedback, and hardware maturation from prototype to rate production. 

• Author and maintain test documentation, safety plans, and compliance records in accordance with DoD, range safety, and energetic materials standards. 

• Mentor junior test engineers and contribute to building robust test capabilities at Castelion facilities and partner ranges. 

• Manage test schedules, resources, and interfaces with internal teams, suppliers, and external test ranges. 

Required Qualifications 

Education: Bachelor’s or Master’s degree in Mechanical Engineering, Aerospace Engineering, Systems Engineering, or related field. 

Experience: 

• 6–10+ years of test engineering experience in aerospace or defense, with at least 3+ years focused on propulsion, solid rocket motors, or missile systems testing. 

• Proven track record developing and executing complex test programs from component through system level, including energetic or hazardous testing. 

Technical Skills 

• Strong hands-on experience with test instrumentation, data acquisition (e.g., LabVIEW, MATLAB, or similar), sensors (pressure transducers, accelerometers, thermocouples), and high-speed data systems. 

• Proficiency in test stand design, fixture development, and environmental test equipment (shakers, thermal chambers, etc.). 

• Experience with static fire testing, thrust measurement, and ballistic performance evaluation for solid rocket motors. 

• Working knowledge of safety protocols for energetic materials, ordnance handling, and high-pressure systems. 

• Familiarity with telemetry, flight test operations, and post-test data analysis tools. 

Preferred Experience 

• Direct experience with solid rocket motor static fire testing or hypersonic propulsion testing on DoD or NASA programs. 

• Background in fast-paced environments (aerospace startups, SpaceX, Anduril, etc.). 

• Experience supporting production acceptance testing and scaling test operations for rate production. 

• Prior work at test ranges or with range safety processes. 

• Familiarity with ITAR-controlled programs and classified testing environments. 

Soft Skills 

• Strong technical problem-solving and analytical skills with a data-driven approach. 

• Excellent collaboration and communication abilities across engineering, manufacturing, and test teams. 

• Proven ability to lead test execution in high-stakes, safety-critical environments. 

• Mentoring mindset and willingness to develop junior engineers. 

• Organized, proactive, and comfortable managing multiple concurrent test activities under tight schedules. 

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 required of the employee for this job. Duties, responsibilities and activities may change at any time with or without notice. 

Additional Eligibility Requirements 

This position may require access to classified information or restricted U.S. Government sites, systems, or information, as determined by the Company and/or applicable U.S. Government requirements. If the position is so designated, your employment in the role may be contingent upon your ability to obtain and maintain the required U.S. Government security clearance or other government authorization, and to satisfy any citizenship or other eligibility requirements imposed by applicable law, regulation, executive order, or government contract requirements. You will be notified if and when such requirements apply. 

Affirmative Action/EEO Statement 

Castelion is an Equal Opportunity Employer. We are committed to providing equal employment opportunities to all applicants and employees without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, age, disability, genetic information, protected veteran status, or any other characteristic protected by applicable federal, state, or local law. 

Castelion is committed to providing reasonable accommodations to qualified individuals with disabilities throughout the application and hiring process. If you require a reasonable accommodation to complete an application, participate in the interview process, or otherwise participate in the hiring process, please contact hr@castelion.com. Requests for accommodation will be considered on an individual basis and handled in accordance with applicable law. 

Castelion is committed to fostering a workplace where employment decisions are based on qualifications, business needs, and the ability to perform the essential functions of the role, with or without reasonable accommodation. 

EAR/ITAR Requirements 

This position requires access to export-controlled information, and as such, employment (or hiring of a contractor) is contingent upon the candidate’s ability to access all applicable export-controlled information without additional export licensing being required by the Bureau of Industry and Security and/or the Directorate of Defense Trade Controls.