{"id":853155,"url":"https://alion.io/job/radiantnuclear-principal-turbomachinery-engineer","title":"Principal Turbomachinery Engineer","company":{"id":690814,"name":"Radiant Nuclear","domain":"radiantnuclear.com","url":"https://alion.io/company/radiantnuclear","size_band":"201-500","is_staffing_agency":false,"employer_type":"direct","is_intermediary":false,"listed_via":null,"ats_vendor":"Ashby","truth_index":{"grade":"A","score":88,"open_postings":26,"ghost_share":0,"stale_share":0.269,"repost_share":0,"time_to_fill_p50_days":71,"computed_at":"2026-11-03T05:54:40Z"}},"role":"Aerospace","role_family":"Aerospace","seniority":"lead","employment_type":"full_time","work_mode":"on_site","remote_scope":null,"remote_scope_basis":null,"remote_working_hours":null,"hiring_geo_confidence":"structured","locations":["El Segundo, United States"],"countries":["US"],"hiring_countries":[],"hiring_countries_total":0,"salary":{"min":200500,"max":314475,"currency":"USD","period":"year","gross":null,"usd_annual":314475},"salary_estimate":null,"experience_years_min":10,"visa_sponsorship":false,"relocation_package":false,"has_equity":true,"technologies":[{"name":"ANSYS","optional":false},{"name":"GD&T","optional":false}],"status":"live","first_seen_at":"2026-04-29T01:05:14Z","employer_posted_date":"2026-04-29","last_verified_at":"2026-11-03T13:17:29Z","board_verified":true,"closed_at":null,"days_open":188,"trust":{"level":"ok","repost_count":0,"flags":[],"days_open":188},"description":"About Radiant\nRadiant 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. Portable nuclear power with rapid-deploy capability can replace similar-sized diesel generators and provide critical asset support for hospitals, data centers, remote sites, and military bases. Radiant’s unique, practical approach to nuclear development leverages modern software engineering to rapidly deliver safe, factory-built microreactors that use existing, well-qualified materials. Founded in 2020, Radiant is on track to test its first reactor at the Idaho National Laboratory this summer, with initial customer deliveries beginning in 2028.\nAbout the Role\nRadiant is seeking a Principal Turbomachinery Engineer to serve as the Responsible Engineer for the turbomachinery within our nuclear-driven power generation system. This role owns the mechanical design, integrity, and performance of the core rotating assembly at the heart of our 1MW closed-loop Brayton cycle.\nYou will define and drive the mechanical architecture of high-speed rotating hardware operating at extreme temperatures, pressures, and rotational speeds. As a deeply technical individual contributor, you will set direction for rotor dynamics, structures, bearings, seals, and system integration while working closely with electrical, thermal, and manufacturing teams.\nThis is a hands-on, high-ownership role focused on technical excellence, sound engineering judgment, and delivering reliable, production-ready turbomachinery.\nResponsibilities & Duties:\nTechnical Ownership & System Architecture\nServe as Responsible Engineer for the turbomachinery mechanical system.\n\nOwn the mechanical architecture and design strategy for high-speed rotating assemblies (up to ~30 krpm).\n\nLead rotor dynamics, structural integrity, and life analysis for rotating components and assemblies.\n\nDefine and flow down requirements from system-level constraints including thermal, structural, and operational environments.\n\nMake key technical decisions on rotor layout, shafting, bearings, seals, materials, and clearances.\n\nEnsure designs meet performance, reliability, safety, and regulatory requirements.\n\nEstablish and uphold standards for mechanical design rigor, analysis quality, and documentation.\n\nMechanical Design & Analysis\nLead detailed design of turbomachinery components including rotors, shafts, housings, and support structures.\n\nTest and validate rotordynamic systems, driving model correlation, risk reduction, and performance verification.\n\nPerform and review structural and thermal analysis to ensure integrity under high-speed and high-temperature operation.\n\nDefine tolerances, fits, stack-ups, and alignment strategies for precision rotating assemblies.\n\nPartner with electrical engineering on alternator rotor integration, including electromagnetic and structural coupling.\n\nCross-Functional Integration\nPartner closely with turbomachinery aero, motor design, thermal, manufacturing, and test teams.\n\nEnsure seamless integration between turbine, compressor, and alternator subsystems.\n\nDrive clear interface definitions across mechanical, electrical, and thermal boundaries.\n\nCollaborate with manufacturing to ensure designs are producible, inspectable, and scalable.\n\nEngage with suppliers on technically critical components and design decisions.\n\nPrototyping, Testing & Validation\nSupport assembly, integration, and test of turbomachinery hardware.\n\nDefine validation strategies including spin testing, thermal testing, and system-level operation.\n\nLead root cause analysis and drive design iteration for test failures or performance gaps.\n\nRemain hands-on in hardware bring-up, troubleshooting, and refinement.\n\nTechnical Influence\nAct as a subject matter expert in turbomachinery mechanical design and rotating systems.\n\nProvide technical guidance and design reviews across the team without direct people management responsibility.\n\nInfluence engineering direction through deep expertise, data-driven decisions, and strong judgment.\n\nContribute to technical roadmap, risk identification, and mitigation strategies.\n\nRequired Qualifications & Skills:\nB.S. in Mechanical Engineering or related field.\n\n8+ years of experience designing high-speed rotating machinery (turbines, compressors, or similar systems).\n\nDeep expertise in structural analysis and mechanical design of turbomachinery.\n\nExperience with bearings, seals, and high-speed shafting design.\n\nExpert-level proficiency with analysis tools (e.g., ANSYS) and advanced use of NX and Teamcenter for complex design, simulation, and product lifecycle management.\n\nStrong understanding of tolerancing, GD&T, and precision mechanical assembly.\n\nExperience owning hardware through design, build, and test cycles.\n\nHands-on experience with assembly, integration, and troubleshooting of turbomachinery.\n\nStrong system-level thinking and mechanical intuition.\n\nExcellent engineering judgment and decision-making capability.\n\nAbility to influence without authority across cross-functional teams.\n\nClear communicator capable of articulating complex technical concepts.\n\nHigh ownership mindset and accountability for hardware outcomes.\n\nAbility to operate effectively in a fast-paced, first-of-a-kind development environment.\n\nDesired Qualifications & Skills:\n10+ years of turbomachinery or rotating equipment experience.\n\nM.S. or Ph.D. in Mechanical Engineering.\n\nExperience with closed-loop Brayton cycle systems or similar energy systems.\n\nFamiliarity with high-temperature materials and extreme environment design.\n\nExperience integrating mechanical systems with high-speed electric machines.\n\nPrior experience as a Responsible Engineer for complex hardware.\n\nExperience scaling hardware from prototype to production.\n\nAdditional Requirements:\nMust be willing to work extended hours and weekends as necessary to accomplish our mission.\n\nMust work 100% onsite at El Segundo HQ.\n\nBenefits and Perks\nStock: Substantial incentive stock plan for all full-time employees.\n\nMedical: 100% up to base silver level plan for employee + 50% dependents, offers up to Platinum plans.\n\nOne Medical: Sponsored memberships for employees and their dependents.\n\nVision: 100% top tier plan coverage + 50% for dependents.\n\nDental: 100% top tier plan coverage, orthodontia extra, 50% for dependents.\n\nVoluntary life, accident, hospital, critical illness, commuter and FSA/HSA are offered as employee contributed benefits.\n\n8-weeks of paid parental leave for all parents. Additional paid pregnancy leave for CA employees.\n\nDaily catered lunch. Free snacks and drinks.\n\nFlexible PTO policy. Remote workday allocation.\n\nCompany and team-bonding events, happy hours and in-person camaraderie.\n\nBeautiful El Segundo headquarters close to the Pacific Ocean.\n\nTotal Compensation and Benefits\nRadiant compensates people for impact and invests in those who continue to raise the bar. Radiant’s new hire compensation package includes base salary, substantial equity grants, and comprehensive health benefits. Total compensation and level are determined through a rigorous evaluation of interview performance, experience, education, and qualifications, and are designed to support continued growth as scope, responsibility, and impact expand at Radiant.\nThe best of today’s advanced reactor builders don’t wait for job postings. They join the winning team. If that’s you, contact us directly for immediate opportunities: .\nWe are an equal opportunity employer and all qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity or expression, pregnancy, age, national origin, disability status, genetic information, protected veteran status, or any other characteristic protected by law.\nThis position involves access to technology that is subject to U.S. export controls. Any job offer made will be contingent upon the applicant’s capacity to serve in compliance with U.S. export controls.","description_format":"text","description_chars":8212,"description_truncated":false,"requirements":{"experience_years_min":10,"management_years_min":null,"team_size_min":null,"manages_managers":false,"education":{"level":"bachelor","optional":false},"security_clearance":false,"languages":[]},"benefits":["Equity","Parental leave"],"hiring_locations":[],"hiring_excludes":[],"relocation_offered":false,"industries":["Nuclear Energy"],"lifecycle":[{"event":"open","at":"2026-09-13T04:41:29Z"}],"visa":[],"liveness":{"score":16,"band":"cold","label":"Long shot","p_open":1,"p_active":0.574,"p_room":0.28,"age_days":188,"expected_fill_days":71,"reasons":["conf:2","win:tail","crowd:"],"computed_at":"2026-11-03T05:54:40Z"},"pay":{"stated_usd_annual":314475,"is_top_pay":true},"html_url":"https://alion.io/job/radiantnuclear-principal-turbomachinery-engineer","json_url":"https://alion.io/job/radiantnuclear-principal-turbomachinery-engineer.json","meta":{"generated_at":"2026-11-03T15:57:17Z","cache_seconds":300,"methodology":"https://alion.io/methodology","terms":"https://alion.io/terms","contact":"https://alion.io/contact","api":"https://alion.io/developers","about":"Alion is a live layer of people, companies and AI agents: who they are, whether they are real and active right now, what they do and how to work with them, readable by people and by agents and paid per call.","catalog":"https://alion.io/catalog.json","usage":{"tier":"crawler_verified","counted_by":"address","units_charged":1,"used_today":22366,"day_limit":null,"remaining_today":null,"minute_limit":300,"resets_at":"2026-11-04T00:00:00Z"}},"offers":[{"id":"company.slices","title":"One company in depth, by slice","status":"live","price":{"credits":0.02,"usd":0.002,"plus_per_slice":{"credits":0.05,"usd":0.005}},"unit":"per company, plus each slice with data","note":"the employer in depth","call":{"mcp_tool":"get_company","arguments":{"id":690814},"rest":"https://alion.io/mcp/rest/get_company?id=690814"},"human":"https://alion.io/catalog?offer=company.slices&for=job%2Fradiantnuclear-principal-turbomachinery-engineer"},{"id":"market.stats","title":"A market slice: pay, demand and time to fill","status":"live","price":{"credits":1,"usd":0.1},"unit":"per slice","note":"pay, demand and time to fill for this role and place","call":{"mcp_tool":"market_stats"},"human":"https://alion.io/catalog?offer=market.stats&for=job%2Fradiantnuclear-principal-turbomachinery-engineer"},{"id":"job.search","title":"Open jobs by role, technology, place, pay and visa","status":"live","price":{"credits":0.02,"usd":0.002},"unit":"per posting in a list","note":"similar open postings","call":{"mcp_tool":"search_jobs"},"human":"https://alion.io/catalog?offer=job.search&for=job%2Fradiantnuclear-principal-turbomachinery-engineer"},{"id":"company.verify","title":"Is this company real and active right now","status":"pilot","price":null,"unit":"per company","request":{"url":"https://alion.io/catalog/request","method":"POST","body":"{\"offer\": \"company.verify\", \"for\": \"job/radiantnuclear-principal-turbomachinery-engineer\", \"note\": \"what you need it for\"}"},"human":"https://alion.io/catalog?offer=company.verify&for=job%2Fradiantnuclear-principal-turbomachinery-engineer"}],"agent":{"mcp":"https://alion.io/mcp/jobs","mcp_open":"https://alion.io/mcp/open","next":[{"tool":"get_job","arguments":{"id":853155}},{"tool":"search_jobs","arguments":{"company":"radiantnuclear.com","detail":"compact"}},{"tool":"match_people","arguments":{"job_id":853155},"note":"people open to offers who fit this vacancy"}],"note":"The same data through MCP tools: https://alion.io/mcp/open needs no sign-in (compact searches, postings, people); https://alion.io/mcp with an Alion account has everything. Docs: https://alion.io/developers"}}