Test Engineer

About the role

Radiant is an El Segundo, CA-based startup building the world's first mass-produced, portable nuclear microreactors. The company's first reactor, Kaleidos, is a 1-megawatt, fail-safe microreactor that can be transported anywhere power is needed and run for up to 5 years without refueling. This role offers a rare opportunity to bridge engineering, operations, and human factors in a highly technical and fast-paced environment.

Responsibilities

• Perform testing as a Test Conductor/Test Director to gain firsthand experience, ensuring procedures align with real-world execution.
• Collaborate closely with engineers to improve test system interfaces, procedural workflows, and software tools.
• Support testing and iterative improvements of fluid, electrical, and structural hardware of the Kaleidos reactor through development, qualification, and acceptance testing.
• Support one-off test campaigns in a fast-paced, minimum-requirements environment to drive hardware risk reduction.
• Ensure compliance with DOE and NRC standards, maintaining strict formatting, clarity, and usability in procedural documentation.

Requirements

• 2+ years of full-time professional experience in engineering problem-solving, including system design, analysis, or testing.
• Bachelor’s degree from an accredited institution in mechanical, manufacturing, or other related engineering discipline.
• Ability to apply first principles thinking to solve problems and make decisions in uncertain or ambiguous situations.
• Background in highly regulated industries (e.g., nuclear, aerospace, aviation, maritime).
• Demonstrated ability to lead projects and work independently.
• Strong technical fundamentals in fluids and thermodynamics.
• Strong written and verbal communication skills.
• Flexible and adaptable mindset - self-driven with the ability to seek out requirements with minimal direction.

Qualifications

• Prior experience working as an operator in fast-paced test environments (e.g., rocket engine testing, turbopump testing, component level testing), with familiarity in safety protocols, and high-reliability operations, high pressure gases, safety engineering (FMECAs, Keep-out Zone).
• Experience designing, fabricating, or operating fluid systems.
• Knowledge of instrumentation including pressure transducers, thermocouples, resistance temperature detectors, and accelerometers.
• Ability to read and interpret engineering standards, technical requirements, and engineering drawings (ASME 31.3, 31.1, and ASME Boiler Code Section III/VIII).
• Hands-on experience in developing technical procedures.
• Experience reviewing test data and hardware performance analysis.
• Prior operations experience with hands-on work designing and commissioning test ground support equipment (test fixtures, fluid systems, electrical systems).
• Proficiency with Ion, Epsilon3, NX CAD, Teamcenter.
• Experience with Beckhoff PLC Controllers.

Skills

• Ability to apply first principles thinking to solve problems and make decisions in uncertain or ambiguous situations.
• Strong technical fundamentals in fluids and thermodynamics.
• Strong written and verbal communication skills.
• Flexible and adaptable mindset - self-driven with the ability to seek out requirements with minimal direction.
• Experience working in highly regulated industries (e.g., nuclear, aerospace, aviation, maritime).
• Experience designing, fabricating, or operating fluid systems.
• Knowledge of instrumentation including pressure transducers, thermocouples, resistance temperature detectors, and accelerometers.
• Ability to read and interpret engineering standards, technical requirements, and engineering drawings (ASME 31.3, 31.1, and ASME Boiler Code Section III/VIII).
• Hands-on experience in developing technical procedures.
• Experience reviewing test data and hardware performance analysis.
• Prior operations experience with hands-on work designing and commissioning test ground support equipment (test fixtures, fluid systems, electrical systems).
• Proficiency with Ion, Epsilon3, NX CAD, Teamcenter.
• Experience with Beckhoff PLC Controllers.

Benefits and Perks

• Stock: Substantial incentive stock plan for all full-time employees.
• Medical: 100% up to base silver level plan for employee + 50% dependents, offers up to Platinum plans.
• One Medical: Sponsored memberships for employees and their dependents.
• Vision: 100% top tier plan coverage + 50% for dependents.
• Dental: 100% top tier plan coverage, orthodontia extra, 50% for dependents.
• Voluntary life, accident, hospital, critical illness, commuter and FSA/HSA are offered as employee contributed benefits.
• 8-weeks of paid parental leave for all parents. Additional paid pregnancy leave for CA employees.
• Daily catered lunch.
• Free snacks and drinks.
• Flexible PTO policy.
• Remote workday allocation.
• Company and team-bonding events, happy hours and in-person camaraderie.
• Beautiful El Segundo headquarters close to the Pacific Ocean.

Pay

$106,500 – $146,475

Schedule

Must work 100% onsite at El Segundo HQ. Must be willing to work extended hours and weekends as necessary to accomplish our mission. Willingness to travel 50% - 60% of the time as needed for projects.