Thermal Engineer (Mid) Seen this week

About the Role

Apex manufactures satellite buses at scale for commercial launch. We are seeking a Thermal Engineer to design, analyze, and optimize spacecraft thermal systems. You will work cross-functionally to develop thermal solutions for avionics, electro-mechanical systems, and spacecraft structures while reducing cost and complexity of traditional satellite thermal subsystems.

Responsibilities

• Develop and maintain spacecraft-level thermal models using Ansys Thermal Desktop and other analytical tools.
• Collaborate with subsystem engineers to design and optimize thermal control systems for avionics and electro-mechanical components.
• Evaluate validity of thermal analysis results and ensure compliance with Mil-Standard, Aerospace TOR, and vendor requirements.
• Plan, execute, and manage thermal testing campaigns, including thermal vacuum (TVAC) and thermal cycling tests.
• Work with mechanical teams to develop passive and active thermal management hardware, including radiators, heaters, heat pipes, and coatings.
• Support thermal subsystem milestone reviews (SRR, PDR, CDR, MRR).
• Perform thermal model correlation using flight and test data.
• Oversee thermal flight hardware integration and quality control.
• Utilize Siemens NX and Teamcenter for thermal design and integration.

Requirements

• 3+ years experience in radiative and conductive thermal modeling of spacecraft systems using Thermal Desktop or similar software.
• Strong understanding of thermal margin definitions and aerospace thermal control standards.
• Experience selecting, sizing, and designing thermal control hardware, including heat pipes, heaters, OSR, SSM, MLI, TEC, thermal paints, and tapes.
• 1+ year experience with thermal cycling and thermal vacuum testing, including setup, instrumentation, and model correlation.

Preferred Qualifications

• Experience with full-vehicle thermal vacuum testing and thermal model correlation.
• Familiarity with 2-phase spacecraft thermal control systems.
• Knowledge of PCBA thermal modeling and thermal interface materials (thermal grease, gap pads, etc.).
• Experience with integrated spacecraft and launch vehicle thermal analysis.
• Proficiency in Python, C/C++, or Matlab for thermal modeling and automation.
• Understanding of SMC-S016 standards or equivalent.
• Familiarity with Atlassian software tools and engineering workflows.

What We Offer

• Equity in Apex.
• 100% company-paid medical, dental, and vision for you and dependents, plus $100k life insurance at no cost.
• 15 days vacation starting, growing to 20+ days annually, plus 10 paid holidays.
• 401(k) plan with 100% match on first 3%, 50% on next 2%.
• 8 weeks paid parental leave plus childcare reimbursement up to $350/day for work-related travel.
• Daily catered lunch and unlimited snacks.
• Monthly office socials, pickleball tournaments, run club, and family gatherings.
• Equipment and setup for productivity.
• Playa Vista office with flexibility to integrate work and life.