Systems Test Engineer

We are looking for a Systems Test Engineer to own the test requirements, automated test station development, integration, validation and performance characterization. In this role, you will take end-to-end ownership for test equipment deployment in hardware domains such as Control Actuation System (CAS), Ignition Safety Devices (ISDs), thrust vector control systems, Flight Avionics electronics, and other instrumentation circuit boards and sub-assemblies. You will lead the development of rigorous test infrastructure, design and execute test campaigns, and help define the production test performance envelope from components to circuit boards, to sub-systems.

This role blends hands-on testing with systems-level thinking. You’‘ll work closely with controls, software, avionics, and mechanical teams to ensure our avionics hardware is verified against realistic, mission-representative conditions.

Responsibilities

• Develop and execute comprehensive test plans across component, subassembly, and integrated system levels.
• Design & Build test fixtures, HIL environments, and automated test rigs to provide test conditions and automated test profiles.
• Validate performance metrics such as power consumption, digital communication, RF performance, torque, response time, bandwidth, and thermal/vibe behavior under nominal and fault scenarios.
• Instrument and log tests for precise characterization and traceability.
• Lead root-cause investigations for performance anomalies or test failures.
• Collaborate with flight hardware development to refine designs based on test results and failure data.
• Drive qualification testing and environmental testing campaigns (vibe, thermal, EMI) for flight hardware.
• Deploy and prove test equipment designs for components, CCA, and sub-assembly test stations.

System Test, Systems Engineering, System Test, Systems Engineering, Avionics, Electronics, Instrumentation, Campaigns, Control Systems, Test Requirements, * B.S. or M.S. in Mechanical, Mechatronics, Aerospace, or Electrical Engineering.

• Experience testing high power sub-assemblies, high-speed digital interfaces, actuators, motion control systems, and RF sub-assemblies for aerospace, automotive, robotics, or defense applications.
• Hands-on experience designing automated test equipment from the ground up utilizing equipment such as power suppliers, DMMs, oscilloscopes, switch matrixes, network analyzers, spectrum analyzers, signal generators, electronic loads, etc.
• Familiarity with embedded control systems and communication protocols (CAN, RS-422/485, SPI, Ethernet, Automotive Ethernet).
• Proficient in using instrumentation and data acquisition systems (e.g., Python, C++,Protobuffs, custom scripts)
• Demonstrated ability to work independently and lead multi-disciplinary integration efforts.

Preferred Skills and Experience

• Experience in RF testing fundamentals or more advanced knowledge of Radar architecture
• Experience with software development for test automation for digital, power, and RF electronics (Python preferred)
• Experience controlling test instrumentation using SCPI, VISA, or PyVISA commands
• Experience developing GUIs or dashboards
• Experience in writing custom scripts for data analysis & database creation
• Experience writing software for Environmental Chambers and/or RF Chambers
• Exposure to flight-like test environments, including environmental stress screening (ESS)
• Experience with fault injection, failure mode testing, and reliability qualification for mission-critical systems
• Working knowledge of C/C++ or Python for custom test tooling or embedded systems debugging
• Background supporting flight test or launch operations.

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.