About Portal Portal Space Systems is on a mission to expand humanity’s freedom of movement in space. We’re building the spacecraft that makes that mission possible. From our Bothell, WA headquarters, we design vehicles with the maneuverability, resilience, and adaptability needed for the next era of orbital operations. Every system we build is in service of a simple idea: space should be more accessible, responsive, and capable. Joining Portal means stepping into a team that believes in bold engineering, fast iteration, and the power of small groups to change what’s possible. If you want your work to directly shape the future of in-space mobility, join us. About the Role The Senior Thermal-Structural Analysis Engineer is responsible for substantiating spacecraft structures operating in high-temperature and thermally severe environments. This role owns coupled thermal–structural analyses used to evaluate stress, deformation, and margin of safety for propulsion-adjacent and elevated-temperature hardware. The position works closely with propulsion, thermal, materials, and test teams to ensure structural integrity is maintained across qualification and flight environments. Primary Responsibilities – Thermal-Structural Substantiation • Develop and maintain coupled thermal–structural finite element models for spacecraft hardware operating in elevated-temperature environments • Perform thermo-mechanical stress, distortion, fatigue, and margin of safety analyses driven by thermal gradients and transient heating • Evaluate high-temperature material behavior and structural performance using analysis and first-principles hand calculations • Partner with propulsion, thermal, and design teams to validate and optimize structural designs for strength, stiffness, weight, and thermal durability • Support structural verification of propulsion-adjacent and thermally driven hardware through qualification and flight readiness • Define, execute, and interpret elevated-temperature material strength testing to characterize mechanical properties and support thermo-mechanical structural verification Additional Responsibilities – Testing, Correlation & Automation • Define and support elevated-temperature material and structural test campaigns to characterize thermo-mechanical behavior • Correlate analytical predictions with high-temperature test data and resolve discrepancies using first-principles reasoning • Develop Python-based tools to automate coupled analysis post-processing, reporting, and verification workflows • Contribute to documentation of thermal-structural assumptions, methods, and verification rationale Basic Qualifications • BS or MS in Aerospace Engineering, Mechanical Engineering, or a related engineering discipline or equivalent • 5+ years of experience in thermal-structural or thermo-mechanical analysis for aerospace systems or related industry experience • Experience performing coupled thermal–structural stress, deformation, and margin of safety analyses Preferred Skills & Experience • Proficiency developing and maintaining coupled thermal–structural FEMs using FEMAP/Nastran or Siemens Simcenter 3D • Experience evaluating elevated-temperature material behavior and structural performance • Experience supporting propulsion or thruster-adjacent hardware operating in high-temperature environments • Proficiency with Python and/or MATLAB for analysis automation, data reduction, and reporting • Experience using version control systems such as Git in an engineering analysis environment • Strong ability to perform coupled thermal–structural analysis for spacecraft hardware in elevated-temperature environments • Deep understanding of thermal gradient-driven stress, distortion, and failure mechanisms • Ability to model, interpret, and validate high-temperature material behavior within structural analyses • Proficiency in using first-principles hand calculations to bound and verify coupled FEM results • Ability to correlate thermo-mechanical analysis with high-temperature test data and resolve discrepancies • Clear technical communication skills for documenting assumptions, methods, and verification rationale Pay Range: $145,000 - $205,000 Compensation and Benefits: Your actual level and base salary will be determined on a case-by-case basis and may vary based on the following considerations: job-related knowledge and skills, education, and experience. At Portal, your base salary is just one part of your total rewards package. You may also be eligible for long-term incentives, in the form of company equity at an exciting time of company growth as well as potential bonuses. You will also receive access to comprehensive medical, vision, and dental coverage, access to a 401(k)-retirement plan, paid parental leave, you may also accrue 3 weeks of paid vacation and will be eligible for 12 or more paid holidays per year as well as sick time. ITAR Statement This position may involve access to technical data and defense-related materials controlled under the International Traffic in Arms Regulations (ITAR). Eligibility to access ITAR-controlled items requires that candidates be U.S. persons, which includes U.S. citizens, lawful permanent residents, and other protected individuals as defined by U.S. law. Employment is contingent upon verification of ITAR eligibility and, where applicable, obtaining any required export authorization or license. Equal Opportunity Statement All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability, or status as a protected veteran.