Lead Integration & Test Engineer

Castelion is bringing a new approach to defense development and production: short, iterative design cycles, rapid testing in development, and modern commercial manufacturing strategies for production at scale. The company is designing, building, and testing next-generation long-range strike weapons systems to give America and its allies a definitive edge and deter future conflicts.

 The Opportunity

Castelion is looking for a Lead Integration & Test Engineer with deep expertise in the integration and verification of warhead systems into complete hypersonic missile vehicles. You will own end-to-end I&T strategies from subassembly through full vehicle level, supporting ground qualification, environmental testing, and flight test campaigns for next-generation hypersonic strike weapons.

You will serve as the technical authority on warhead-vehicle integration and test, collaborating closely with design, manufacturing, propulsion, radar, quality, and mission assurance teams to meet stringent DoD standards and mission requirements. Key outcomes for 2026 include delivering a production-ready I&T process in Rio Rancho, New Mexico; developing a scale plan from LRIP to thousands of units per year; supporting a rapid flight test cadence; and building the integration and test engineering team that can independently support future facility development and production execution.

What You'll Do

• •      Lead warhead-to-vehicle integration activities including mechanical mating, electrical interface verification, fuze and S&A installation, and safe separation testing


• •      Develop and execute comprehensive vehicle-level I&T plans covering functional checkout, ordnance arming sequences, environmental qualification, and system verification


• •      Design and commission integration tooling, test fixtures, and automated test equipment for warhead handling and full missile assembly


• •      Oversee environmental stress screening (thermal, vibration, shock, EMI/EMC) and functional performance testing of integrated warhead-vehicle systems


• •      Support flight test preparation, range coordination, pre-flight checkout, and post-flight data analysis and anomaly resolution


• •      Perform root-cause investigations and corrective actions for integration and test anomalies using FRACAS and fault tree analysis


• •      Ensure full compliance with explosive safety standards, DoD 6055.09, MIL-STD-810, and mission assurance requirements


• •      Mentor I&T engineers and lead cross-functional teams during build and test campaigns


• •      Drive continuous improvement in integration processes, test automation, and digital thread implementation for faster iteration cycles

You Should Have

• •      8+ years of experience in integration and test for complex aerospace or defense systems


• •      4+ years specifically working with warheads, munitions, or energetic systems integration


• •      Demonstrated leadership of vehicle-level integration and test campaigns, preferably on missile or hypersonic programs


• •      Strong experience with ordnance handling, safe-and-arm devices, and energetic materials integration


• •      Proficiency in test automation using LabVIEW, Python, or MATLAB, plus data acquisition systems and telemetry


• •      Hands-on experience with environmental testing and ordnance functional verification


• •      Experience with requirements management, configuration control, and 3D CAD for integration planning


• •      U.S. citizenship or permanent resident status required (ITAR)


• •      Bachelor's or Master's degree in Aerospace Engineering, Mechanical Engineering, Systems Engineering, or a related field

Nice to Have

• •      Direct experience on DoD missile or hypersonic warhead programs


• •      Background in fast-paced development environments


• •      Knowledge of insensitive munitions and advanced warhead designs


• •      Prior flight test support at ranges


• •      Experience with classified programs and TS/SCI level work

Compensation and Benefits

Long-term stock incentives for all employees. Comprehensive medical, vision, and dental insurance, plus four weeks of paid time off per year.