Senior Build Engineer, Turbomachinery

The role

You will lead assembly, integration and build execution of turbomachinery hardware for a portable nuclear microreactor. The role is hands-on, covering prototype and first-article builds, build process development, and working with design, manufacturing and test teams.

What you will do

• Lead hands-on assembly, integration and troubleshooting of compressors, turbines, rotors, electric motors, bearings, seals and housings.
• Own precision assembly operations such as rotor stacking, bearing installation, balancing, alignment and mechanical fit-up.
• Interpret engineering drawings, GD&T, tolerance stack-ups and 3D CAD models.
• Drive first-article build execution so hardware is ready for testing and validation.
• Develop assembly processes, work instructions, alignment procedures and torque specifications.
• Design custom assembly tooling, fixtures and work-holding solutions.
• Maintain detailed build documentation, inspection results and nonconformances.
• Lead root cause investigations and corrective actions for assembly defects and mechanical failures.
• Support hardware testing, including pre-test inspections and post-test teardown.
• Mentor junior engineers and technicians on precision assembly and build quality.

Required qualifications

• Bachelor's degree in Mechanical Engineering, Aerospace Engineering or a related engineering discipline.
• 5+ years of relevant experience in mechanical assembly, hardware integration, manufacturing or build engineering with complex mechanical systems.
• Demonstrated hands-on experience assembling, integrating and troubleshooting precision mechanical hardware.
• Strong understanding of GD&T, tolerance stack-ups, mechanical fits, fasteners, torque requirements and alignment principles.
• Proficiency in reading engineering drawings, assembly documentation and 3D CAD models.
• Experience developing assembly procedures, troubleshooting hardware issues and improving build processes.
• Strong mechanical aptitude and first-principles problem-solving skills.
• Ability to work effectively across design, manufacturing and test engineering teams.

Nice to have

• Direct experience with turbomachinery, gas turbines, compressors, high-speed rotating equipment or power generation systems.
• Experience with precision rotor assembly, dynamic balancing, bearing installation and shaft alignment.
• Familiarity with precision measurement tools such as dial indicators, micrometers and bore gauges.
• Experience designing custom assembly fixtures, tooling and ground support equipment.
• Familiarity with rotor dynamics, thermal growth, bearing preload and interference fits.
• Experience supporting first-article builds, prototype development and hardware testing.
• Experience transitioning complex hardware from development to repeatable production.

Benefits

• Substantial incentive stock plan for all full-time employees.
• Medical coverage: 100% of base silver level plan for employee and 50% for dependents, with up-to-Platinum options.
• Sponsored One Medical memberships for employees and dependents.
• Vision coverage: 100% top tier for employee and 50% for dependents.
• Dental coverage: 100% top tier for employee, orthodontia extra, 50% for dependents.
• Voluntary life, accident, hospital, critical illness, commuter and FSA/HSA benefits, employee contributed.
• 8 weeks of paid parental leave for all parents, plus additional paid pregnancy leave for CA employees.
• 100% covered Nuclear Engineering Certificate Program with Penn State University for eligible employees.
• Daily catered lunch, free snacks and drinks.
• Flexible PTO policy and remote workday allocation.
• Company and team events, happy hours.

Before you apply

• Must be able to serve in compliance with U.S. export controls; any job offer is contingent on this.
• Access to technology subject to U.S. export controls applies to this role.

About the company

Radiant is an El Segundo, CA company building transportable nuclear microreactors. Its first reactor, Kaleidos, is 1 megawatt and is under contract to the U.S. Army, Navy and Air Force.