What are the responsibilities and job description for the Prototype Engineer position at The Arena?
Prototype & Test Engineer
Location: Hybrid | Northern, VA
Clearance: Must be eligible to obtain a Secret or Top Secret/SCI security clearance
Employment Type: Full-time, salaried, with full benefits
About the Company:
Our client is developing a next-generation class of compact, long-duration energy systems designed to deliver radically autonomous, resilient power for terrestrial and off-world applications. Their flagship technology is a modular microreactor system capable of providing uninterrupted power for multi-year missions—engineered for reliability, autonomy, and scalability.
Founded by leaders from advanced energy, defense, and aerospace backgrounds, the company operates at the intersection of nuclear innovation, materials science, and applied thermofluidic engineering. With accelerating U.S. government demand (DoD, NASA, DOE) and modernizing regulatory frameworks, they are seizing a once-in-a-generation opportunity to redefine how resilient power systems are designed, tested, and deployed.
About the Role:
As a Prototype & Test Engineer, you will be hands-on with the hardware that brings this system from concept to operational reality. You’ll design, assemble, and validate reactor subsystems, converting early-stage concepts into working prototypes and structured test campaigns.
This is a high-responsibility, high-impact engineering role where your work directly determines whether the system stands up to the demands of physics, regulation, and mission-critical performance. You’ll work shoulder-to-shoulder with a small, elite team of mechanical, nuclear, and systems engineers, bridging theory and experimental execution.
Primary Responsibilities:
Prototype Design & Integration
- Design and integrate mechanical and instrumentation components for prototype systems (thermal loops, test vessels, flow structures, pressure manifolds, and support rigs).
- Develop 3D CAD models, fabrication drawings, and bills of material to support prototype assembly.
- Drive design-for-manufacturing and design-for-test outcomes throughout the development cycle.
- Collaborate with vendors, machinists, and fabricators to realize hardware in support of subsystem and system-level testing.
Test Planning & Execution
- Develop and execute test plans to validate subsystem and integrated system performance under thermal, pressure, and mechanical load conditions.
- Select, integrate, and operate instrumentation, data acquisition (DAQ), and control systems for test hardware.
- Lead the setup, commissioning, and safe execution of thermal-fluid, pressure, and performance tests.
- Record, analyze, and interpret experimental data to inform design optimization and validate physical models.
- Implement best practices in safety, configuration management, and quality assurance for prototype and test systems.
Required Experience:
- Bachelor’s degree in Mechanical, Nuclear, Aerospace, or a related STEM field.
- 5–8 years of experience in mechanical prototyping, hardware development, or system-level testing, ideally with thermal-fluid or high-temperature gas systems.
- Proficiency in 3D CAD (SolidWorks, Creo, or similar) and technical drawing.
- Hands-on experience with instrumentation, data acquisition, and test control hardware/software.
- Strong knowledge of thermal-fluid systems, mechanical assembly, and basic structural or pressure analysis.
- Demonstrated ability to thrive in a fast-moving, multidisciplinary environment that blends R&D with field execution.
Preferred Experience:
- Experience with high-pressure gas loops, heat exchangers, thermal management, or cryogenic systems.
- Background in oil & gas, nuclear, hydrogen, or propulsion test environments.
- Familiarity with control systems integration (PLC, DCS, or custom DAQ frameworks).
- Experience commissioning or operating instrumented test rigs for performance or endurance testing.
- Exposure to reactor design, process safety, or high-energy system qualification is a plus.
Why Join This Team:
- Be part of a team building category-defining energy hardware from the ground up.
- Own critical contributions from day one in a company where execution speed and innovation matter.
- Work directly with world-class engineers and operators tackling real thermofluidic and materials challenges that haven’t been solved before.
- Play a pivotal role in bringing autonomous power systems to Earth, the Moon, and beyond.