Spacecraft Thermal Engineer III

About Firefly Aerospace Firefly Aerospace is a space and defense technology company on a mission to reliably and repeatedly launch, land, and operate space systems from Earth to the Moon and beyond. As the partner of choice for critical space missions, Firefly is the first commercial company to launch a satellite to orbit with 24-hour notice and the first company to achieve a successful Moon landing. Headquartered in north Austin, Texas, Firefly is looking for passionate, hardworking innovators to join our team and help fuel our successful trajectory into space.

Summary Firefly Senior Thermal Engineers provide technical leadership for spacecraft thermal analysis across multiple vehicle programs. They develop analytical approaches for complex thermal challenges, establish modeling strategies, mentor engineers across the organization, and influence major program decisions throughout vehicle development.

This role requires deep expertise in spacecraft thermal engineering, strong technical judgment, and the ability to independently lead multidisciplinary efforts involving analysis, testing, and vehicle design.

Responsibilities

• Lead thermal analyses that drive major vehicle design decisions across multiple spacecraft programs.
• Own the architecture, validation, and long-term maintenance of integrated spacecraft thermal models.
• Develop innovative analytical methods, workflows, and automation that improve team capability and efficiency.
• Lead thermal trade studies involving mission environments, propulsion effects, lunar surface interactions, cryogenics, and advanced thermal control technologies.
• Define thermal analysis strategies supporting conceptual design through flight.
• Organize and lead testing, including vehicle-level thermal vacuum testing.
• Serve as the point of contact for the thermal control subsystem during launch operations.
• Lead model validation efforts using thermal vacuum, qualification, acceptance, and flight data.
• Mentor and technically review work performed by thermal engineers across multiple experience levels.
• Represent Thermal Engineering during customer reviews and major program design reviews.
• Provide technical leadership during anomaly investigations and rapid-response engineering efforts.
• Influence organizational best practices, analytical standards, and long-term capability development.
• Support hiring, technical interviews, and development of the thermal engineering team.

Qualifications Required

• B.S. in Aerospace Engineering, Mechanical Engineering, Physics, or related field
• Approximately 8–15+ years of spacecraft thermal analysis experience
• Expert knowledge of spacecraft heat transfer and thermal control systems
• Extensive experience with Thermal Desktop and industry-standard thermal analysis software
• Demonstrated success leading thermal analyses through design, testing, and flight
• Experience with instrumentation and testing thermal hardware
• Experience correlating analytical models using environmental and flight data
• Strong programming skills using Python, MATLAB, or similar languages
• Excellent technical leadership and communication skills
• Proven ability to independently scope, execute, defend, and communicate complex analyses

Desired

• M.S. or Ph.D.
• Experience supporting NASA, DoD, or commercial spacecraft programs
• Experience developing new thermal analysis methodologies or software automation
• Familiarity with thermal standards (e.g., GSFC-STD-7001B, SMC-S-016, RCC-319, Spacecraft Payload requirements)
• Experience organizing and executing thermal vacuum tests
• Experience with advanced spacecraft thermal control technologies, lunar environments, plume heating, and mission-specific thermal phenomena