Full Description

About Castelion

Castelion is bringing a new approach to defense development and production: one that focuses on short, iterative design cycles, rapid testing in development, and modern commercial manufacturing strategies for production at scale. We're designing, building, and testing next generation long range strike weapons systems to give America and its Allies a definitive edge and deter future conflicts. Development Test Engineer The Development Test Engineer owns the planning, execution, and analysis of tests that turn designs into flight-ready hardware. This role sits at the center of engineering, manufacturing, and operations—translating requirements into real-world validation through benchtop, environmental, subsystem, and vehicle-level testing. You will design test hardware, write procedures, run tests, break things early, and close the loop back into design with clear data and recommendations. This is a hands-on role for engineers who thrive in fast-paced, ambiguity-heavy environments and believe the fastest way to learn is to test real hardware. Responsibilities Own development and qualification testing for avionics, mechanisms, propulsion, structures, and integrated vehicle subsystems Design and build test fixtures, ground support equipment (GSE), and instrumentation for benchtop, environmental, and system-level tests Author test plans, procedures, and reports aligned with program requirements and qualification intent Execute vibration, thermal, shock, EMI/EMC, functional, and performance testing Instrument hardware and vehicles with sensors (strain, temp, pressure, accel, current/voltage) and DAQ systems Lead anomaly detection, root-cause analysis, and corrective action closure Partner closely with design engineering to feed test results back into rapid design iteration Support integration operations, range testing, and flight test campaigns as needed Maintain rigorous configuration control, data management, and test documentation Improve test infrastructure, automation, and data quality to increase test cadence and learning velocity Basic Qualifications Bachelors degree in Mechanical, Electrical, Aerospace, or related engineering field 3+ years of hands-on development and test experience (academic, industry, or both) Experience planning and executing hardware tests from concept through report-out Proficiency with test instrumentation and lab equipment (DAQs, oscilloscopes, power supplies, sensors) Ability to design and fabricate simple test fixtures and GSE (CAD + shop familiarity) Strong debugging, troubleshooting, and root-cause analysis skills Comfortable working across disciplines in high-ownership environments Willingness to support extended hours, weekends, travel, and on-site operations during critical test campaigns Operates with high ownership, bias to action, attention to detail, and a test-driven engineering mindset Comfortable working in fast-moving environments where hardware is the source of truth Preferred Skills and Experience Aerospace, missile, launch vehicle, space, or defense hardware testing