Senior Mechanical Design Engineer - Cover Gas Systems

Responsible Engineer (RE) for the Cover Gas SystemAs the Responsible Engineer (RE) for the Cover Gas System, you will lead the design, development, testing, and validation of mechanical systems that monitor fission products released from nuclear fuel and maintain an inert reactor core environment. You will own the mechanical architecture of the system, sizing and integrating components that interface with electrical and software subsystems, and collaborating closely across disciplines to define requirements, documentation, and verification plans.The ideal candidate has a strong background in fluid system design, particularly involving compressible flow, and experience developing hardware for demanding environments. Familiarity with radiation detection technologies (e.g., scintillators, Geiger-Müller counters, or solid-state detectors) is a strong differentiator.Roles and Responsibilities:Design, build, and test the reactor's cover gas system, hardware, assemblies and detectors.Concept and develop custom fluid-dynamic features to support fission product detection and inert environment retention.Define design criteria, requirements, system architecture, and verification/validation test plans.Collaborate closely with cross-functional teams across thermal, structural, neutronics, controls, and simulation disciplines.Engineer components for high-temperature, high-stress, and radiation environments using metals, ceramics, and other advanced materials.Perform design-for-manufacturability (DFM) assessments and execute tradeoffs across performance, cost, schedule, and risk.Document technical decisions and tradeoffs, and present recommendations to senior leadership.Basic Qualifications:Bachelor's degree in engineering5+ years of experience in full-cycle design engineering roles, including hands-on CAD, analysis, build, and testExperience designing, sizing, and integrating fluid systems, preferably involving compressible flowExperience performing and interpreting computational fluid dynamics (CFD) analyses.Preferred Skills & Experience:Experience in the Nuclear, Aerospace, or Oil and Gas industriesExperience in a demanding fast-paced development environmentExperience with design engineering tools such as NX, ANSYS or Femap, and other product lifecycle softwareExperience with engineering scripting languages such as Python and MATLABExperience working with radiation detectorsAdditional Requirements:Ability to work long hours and weekends as necessary to support critical milestonesLocation:The Antares HQ is located in Torrance, CA in a 322,000 square foot, brand new facility featuring large open spaces for team collaboration, R&D, and production, as well as easy access to the 405, 105, and 110 freeways. Our HQ is in the heart of Los Angeles' vibrant emerging tech ecosystem alongside many other high growth startups and enterprises.Culture:Think in Systems - Energy and Defense are complex ecosystems with numerous stakeholders with competing priorities with emergent and path-dependent properties. Over-optimizing the components often degrades the systemObsess over the End User - The customer and end user are often not the same. We will never build globally competitive commercial products if we lose sight of our end users and their entire interaction with the product life cycleBe Unconstrained by Convention - Our only limits are the laws of physics.

Many, even experts, will say what we are working on is impossible. They said the same about SpaceX reusing rockets. Generationally impactful companies, by definition, must accomplish the seemingly impossible. If it were easy, it would have already been done. Never shy away from a solution because it has never been tried before, and never choose to do something because that's "how it's always been done"Go Where the Work Is - Never miss a chance to meet a customer, user, or stakeholder face to face, even if that means hopping on a plane. If you can't make it, find a teammate who can channel your intentions and go in your place.

Deep work can be done from anywhere, but we believe teams are built in person, and aim to maximize our time togetherOperate in the Grey - Embrace nuance in pursuit of truth. Question every fundamental assumptionEqual Opportunity:Antares is an Equal Opportunity Employer. Employment decisions are based solely on merit, competence, and qualifications, without regard to race, color, religion, gender, national origin/ethnicity, veteran status, disability status, age, sexual orientation, gender identity, marital status, mental or physical disability, or any other legally protected status.ITAR RequirementsTo conform to U.S. Government export regulations, applicant must be a U.S. citizen or national, U.S. lawful, permanent resident (aka green card holder), Refugee under 8 U.S.C.

§ 1157, or Asylee under 8 U.S.C. § 1158, or be eligible to obtain the required authorizations from the U.S. Department of State. Learn more about the ITAR here.