Propulsion Engineer

Turning Space into a Transportation Layer for Earth Who We Are: Inversion builds advanced reentry systems to deliver next-generation capabilities from space. Our mission is to make Earth radically more accessible by turning Low-Earth Orbit into an on-demand logistics domain. We see space not as a destination, but as a platform - one that unlocks unprecedented speed and global reach. Our spacecraft are designed to deliver payloads anywhere on Earth in under an hour, operating through extreme reentry conditions and landing with high precision. These systems open the door to new ways of testing, delivering, and operating at hypersonic speeds. Inherently dual-use, our technology is built to meet urgent national security needs while laying the groundwork for future commercial applications. Backed by leading investors including Y Combinator, Spark Capital, and Lockheed Martin Ventures, and working with partners such as the U.S. Space Force and NASA, Inversion is pushing the boundaries of what is possible in space-based defense and logistics. As a Senior Propulsion and Energetics Thermofluids Engineer at Inversion, you will report to the Head of Test, Propulsion & Energetics. In this role, you will be the primary technical authority on vacuum chamber systems for a hypersonic plasma wind tunnel. You will design and develop the mechanical structures and devices to activate a vacuum system and its requisite heat exchanger systems for a high-energy test bed to expand Inversion’s depth in hypersonic and reentry material testing. Key Responsibilities Lead the design and development of vacuum chamber and heat exchange cooling systems tailored to our high-energy plasma test environment. This includes detailed mechanical design with executable drawings and technical specifications. Conduct thorough thermal and fluid analyses on industrial-scale equipment. Lead high-fidelity, transient thermal analysis including 3D conjugate heat transfer (CHT) modeling, aerodynamic heating boundary conditions, and internal radiative/conductive heat transfer. Drive design trades across performance, manufacturability, schedule, and cost. Own the sizing, selection, and structural interface design between the test facility and thermal protection systems (TPS) and internal insulation materials. Own CAD models, drawings, release packages, and bill of materials for prototype and flight-like hardware. Support prototype design, hands-on integration, fit checks, and issue resolution during build. Provide additional mechanical tooling and mechanism design bandwidth for test activities as needed. Work closely with vehicle, manufacturing, test, supply chain, and technician teams to bring designs from concept through fabrication and integration. Partner with outside vendors and suppliers to source parts, review manufacturability, and accelerate development. Required Qualifications Bachelor’s degree in Mechanical Engineering, Aerospace Engineering, or equivalent technical experience. 5+ years of experience in thermal design, modeling, and analysis of high-temperature systems. Strong practical mechanical design skills related to industrial systems, mechanisms, high thermal-load systems, and user interfaces. High familiarity with CAD software, such as Siemens NX. Experience producing engineering drawings and applying standard dimensioning and tolerancing (GD&T) per ASME Y14.5. Expertise in industry-standard thermal analysis software, such as Thermal Desktop, ANSYS Thermal, or equivalent tools. Strong foundational knowledge of multi-physics heat transfer (conduction, radiation, high-speed convection) and thermodynamics. Demonstrated experience taking complex thermal systems through the complete lifecycle from conceptual design through hardware testing. Proven ability to operate independently, make high-consequence technical decisions under uncertainty, and establish company-wide technical standards. Excellent verbal and written communication skills. Desired Qualifications Master’s or Ph.D. in Mechanical or Aerospace Engineering with a focus on heat transfer, fluid dynamics, or thermodynamics. Direct experience with designing or operating large-scale vacuum systems. Direct experience with industrial facility mechanical design and process engineering. Direct experience modeling aerothermal hypersonic environments, plasma interactions, or conjugate heat transfer (CHT) coupled with CFD solvers. Experience supporting prototype builds and rapid design iteration in a hardware-rich environment. Experience designing tooling, fixtures, or support equipment for integration and test. Experience using hand calculations and/or FEA to inform mechanical design decisions. Prior experience working in startups and/or small independent teams. Our office headquarters is located in Playa Vista, CA. This position requires in office presence. The California annual base salary for this role is currently $137,000 - $193,000. Pay Grades are determined by role, level, location, and alignment with market data. Individual pay will be determined on a case-by-case basis and may vary based on the following considerations: interviews and an assessment of several factors that are unique to each candidate, job-related skills, relevant education and experience, certifications, abilities of the candidate and internal equity. ITAR Compliance: To conform to U.S. Government space technology export regulations, including the International Traffic in Arms Regulations (ITAR) you must be a U.S. citizen, lawful permanent resident of the U.S., protected individual as defined by 8 U.S.C. 1324b(a)(3), or eligible to obtain the required authorizations from the U.S. Department of State. Learn more about the ITAR here. Equal Employment Opportunity: Inversion provides equal employment opportunities to all employees and applicants without regard to race, color, religion, age, sex, gender identity, sexual orientation, national origin, veteran status, or disability. Inversion collects and processes personal data in accordance with applicable data protection laws. If you are a US Job Applicant see the CCPA Privacy Policy Notice for further details. #J-18808-Ljbffr